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1

Bifunctional Catalysts for the Selective Catalytic Reduction...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Reduction (DEER) Conference Presentation: Argonne National Laboratory 2004deermarshall.pdf More Documents & Publications Bifunctional Catalysts for the Selective Catalytic...

2

Selective Catalytic Reduction and Exhaust Gas Recirculation Systems...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Reduction and Exhaust Gas Recirculation Systems Optimization Selective Catalytic Reduction and Exhaust Gas Recirculation Systems Optimization A patented EGR-SCR approach was shown...

3

Understanding ammonia selective catalytic reduction kinetics...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

temperature programmed reduction (TPR), and electron paramagnetic resonance (EPR) spectroscopy. Catalytic properties are examined using NO oxidation, ammonia oxidation,...

4

Bifunctional Catalysts for the Selective Catalytic Reduction...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

3 DEER Conference Presentation: Argonne National Laboratory 2003deermarshall.pdf More Documents & Publications Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels as...

5

Correlations between surface structure and catalytic activity/selectivity  

SciTech Connect (OSTI)

Objective is to address the keys to understanding the relation between surface structure and catalytic activity/selectivity. Of concern are questions related to enhanced catalytic properties of mixed-metal catalysts and critical active site requirements for molecular synthesis and rearrangement. The experimental approach utilizes a microcatalytic reactor contiguous to a surface analysis system, an arrangement which allows in vacuo transfer of the catalyst from one chamber to the other. Surface techniques being used include Auger (AES), UV and X-ray photoemission spectroscopy (UPS and XPS), temperature programmed desorption (TPD), low energy electron diffraction (LEED), high resolution electron energy loss spectroscopy (HREELS) and infrared reflection-absorption spectroscopy (IRAS). Our research program builds upon our previous experience relating the results of single crystal kinetic measurements with the results obtained with supported analogs. As well we are exploiting our recent work on the preparation, the characterization, and the determination of the catalytic properties of ultra-thin metal and metal oxide films. The program is proceeding toward the study of the unique catalytic properties of ultrathin metal films; the investigation of the critical ensemble size requirements for principal catalytic reaction types; and the modelling of supported catalysts using ultra-thin planar oxide surfaces.

Goodman, D.W.

1992-10-01T23:59:59.000Z

6

Selective dehydrogenation of propane over novel catalytic materials  

SciTech Connect (OSTI)

The conversion of small alkanes into alkenes represents an important chemical processing area; ethylene and propylene are the two most important organic chemicals manufactured in the U.S. These chemicals are currently manufactured by steam cracking of ethane and propane, an extremely energy intensive, nonselective process. The development of catalytic technologies (e.g., selective dehydrogenation) that can be used to produce ethylene and propylene from ethane and propane with greater selectivity and lower energy consumption than steam cracking will have a major impact on the chemical processing industry. This report details a study of two novel catalytic materials for the selective dehydrogenation of propane: Cr supported on hydrous titanium oxide ion-exchangers, and Pt nanoparticles encapsulated in silica and alumina aerogel and xerogel matrices.

Sault, A.G.; Boespflug, E.P.; Martino, A.; Kawola, J.S.

1998-02-01T23:59:59.000Z

7

Impact of Biodiesel-Based Na on the Selective Catalytic Reduction...  

Broader source: Energy.gov (indexed) [DOE]

Impact of Biodiesel-Based Na on the Selective Catalytic Reduction (SCR) of NOx Using Cu-zeolite Impact of Biodiesel-Based Na on the Selective Catalytic Reduction (SCR) of NOx Using...

8

Method and apparatus for monitoring a hydrocarbon-selective catalytic reduction device  

DOE Patents [OSTI]

A method for monitoring a hydrocarbon-selective catalytic reactor device of an exhaust aftertreatment system of an internal combustion engine operating lean of stoichiometry includes injecting a reductant into an exhaust gas feedstream upstream of the hydrocarbon-selective catalytic reactor device at a predetermined mass flowrate of the reductant, and determining a space velocity associated with a predetermined forward portion of the hydrocarbon-selective catalytic reactor device. When the space velocity exceeds a predetermined threshold space velocity, a temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is determined, and a threshold temperature as a function of the space velocity and the mass flowrate of the reductant is determined. If the temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is below the threshold temperature, operation of the engine is controlled to regenerate the hydrocarbon-selective catalytic reactor device.

Schmieg, Steven J; Viola, Michael B; Cheng, Shi-Wai S; Mulawa, Patricia A; Hilden, David L; Sloane, Thompson M; Lee, Jong H

2014-05-06T23:59:59.000Z

9

Method for selective catalytic reduction of nitrogen oxides  

DOE Patents [OSTI]

A method for catalytically reducing nitrogen oxide compounds (NO.sub.x, defined as nitric oxide, NO, +nitrogen dioxide, NO.sub.2) in a gas by a material comprising a base metal consisting essentially of CuO and Mn, and oxides of Mn, on an activated metal hydrous metal oxide support, such as HMO:Si. A promoter, such as tungsten oxide or molybdenum oxide, can be added and has been shown to increase conversion efficiency. This method provides good conversion of NO.sub.x to N.sub.2, good selectivity, good durability, resistance to SO.sub.2 aging and low toxicity compared with methods utilizing vanadia-based catalysts.

Mowery-Evans, Deborah L. (Broomfield, CO); Gardner, Timothy J. (Albuquerque, NM); McLaughlin, Linda I. (Albuquerque, NM)

2005-02-15T23:59:59.000Z

10

Method For Selective Catalytic Reduction Of Nitrogen Oxides  

DOE Patents [OSTI]

A method for catalytically reducing nitrogen oxide compounds (NO.sub.x, defined as nitric oxide, NO, +nitrogen dioxide, NO.sub.2) in a gas by a material comprising a base metal consisting essentially of CuO and Mn, and oxides of Mn, on an activated metal hydrous metal oxide support, such as HMO:Si. A promoter, such as tungsten oxide or molybdenum oxide, can be added and has been shown to increase conversion efficiency. This method provides good conversion of NO.sub.x to N.sub.2, good selectivity, good durability, resistance to SO.sub.2 aging and low toxicity compared with methods utilizing vanadia-based catalysts.

Mowery-Evans, Deborah L. (Broomfield, CO); Gardner, Timothy J. (Albuquerque, NM); McLaughlin, Linda I. (Albuquerque, NM)

2005-02-15T23:59:59.000Z

11

Calibration and performance of a selective catalytic reduction (SCR) bench rig for NOx? emissions control  

E-Print Network [OSTI]

A laboratory test rig was designed and built to easily test SCR (Selective Catalytic Reduction) technology. Equipped with three 6 kW heaters, connections for liquid N2 and an assortment of test gases, and a connection with ...

Castro Galnares, Sebastián (Castro Galnares Wright Paz)

2008-01-01T23:59:59.000Z

12

Impact of Biodiesel-Based Na on the Selective Catalytic Reduction...  

Broader source: Energy.gov (indexed) [DOE]

Biodiesel-Based Na on the Selective Catalytic Reduction (SCR) of NO x Using Cu-zeolite D. William Brookshear 1 , Todd J. Toops 2 , William Rohr 1 , Ke Nguyen 1 , and Bruce G....

13

Superior catalysts for selective catalytic reduction of nitric oxide. Quarterly technical progress report, April 1, 1995--June 30, 1995  

SciTech Connect (OSTI)

Efforts continued towards the synthesis of new pillared clay catalysts for the selective catalytic reduction of nitric oxide by ammonia. The possibility of utilizing hydrocarbons was also investigated.

Li, W.B.; Yang, R.T.

1995-12-01T23:59:59.000Z

14

Educating Consumers: New Content on Diesel Vehicles, Diesel Exhaust Fluid, and Selective Catalytic Reduction Technologies on the AFDC (Presentation)  

SciTech Connect (OSTI)

Presentation covers new content available on the Alternative Fuels and Advanced Vehicle Data Center regarding diesel vehicles, diesel exhaust fluid, and selective catalytic reduction technologies.

Brodt-Giles, D.

2008-08-05T23:59:59.000Z

15

DOI: 10.1002/chem.200700579 Selective Catalytic Oxidation of Ethanol to Acetic Acid on Dispersed  

E-Print Network [OSTI]

% ethanol conversion) were much higher than in previous re- ports. The presence of TiO2 during syn- thesisDOI: 10.1002/chem.200700579 Selective Catalytic Oxidation of Ethanol to Acetic Acid on Dispersed Mo, easily separated from organic reactants and products, and gas-phase process- es that avoid solid

Iglesia, Enrique

16

Use of Simulation To Optimize NOx Abatement by Absorption and Selective Catalytic Reduction  

E-Print Network [OSTI]

Use of Simulation To Optimize NOx Abatement by Absorption and Selective Catalytic Reduction Andrew This paper describes the development of an ASPEN PLUS simulation model for a commercial NOx abatement system nitric acid production and the abatement of NOx- laden effluent streams for environmental protection.1

Liu, Y. A.

17

Correlating Catalytic Methanol Oxidation with the Structure and Oxidation State of Size-Selected Pt Nanoparticles  

E-Print Network [OSTI]

of this process is a limiting factor in the performance of direct methanol fuel cells, which produce electricityCorrelating Catalytic Methanol Oxidation with the Structure and Oxidation State of Size-Selected Pt nanoparticles (NPs) prepared by micelle encapsulation and supported on -Al2O3 during the oxidation of methanol

Kik, Pieter

18

Pillared clays as superior catalysts for selective catalytic reduction of nitric oxide. Second semiannual report, 1996  

SciTech Connect (OSTI)

During the first six months of the program, the work has progressed as planned. We have constructed a reactor system and assembled all laboratory essentials for conducting the three-year project. First, the catalytic activities of the Cu(2+) ion exchanged alumina-pillared clay for the selective catalytic reduction of NO by ethylene were measured. The temperature range was 250-500{degrees}C. The activities of this catalyst were substantially higher than the catalyst that has been extensively studied in the literature, Cu-ZSM-5. Fourier Transform Infrared Spectroscopy (FTIR) was used to study the acidity of the catalyst. The second part of the work was an in-depth FTIR study of the NO decomposition mechanism on the catalyst. This was planned as the first and the key step to obtain an understanding of the reaction mechanism. Key surface intermediates were identified from the FTIR spectra, and a redox type Eley-Rideal mechanism was proposed for the NO decomposition on this catalyst. This report will be divided into two parts. In Part One, we report results on the catalytic activities of the Cu-alumina-pillared clay and a direct comparison with other known catalysts. In Part two, we focus on the FTIR study and from the results, we propose a NO decomposition mechanism on this new catalyst. Plans for the next six months include tests of different pillared clays as well as the catalytic mechanism. The micro reactor will continue to be the key equipment for measuring the catalytic activities. FTIR will continue to be the major technique for identifying surface species and hence understanding the reaction mechanism.

Yang, R.T.; Li, W.B.; Sirilumpen, M.; Tharapiwattananon, N.

1997-08-01T23:59:59.000Z

19

PILLARED CLAYS AS SUPERIOR CATALYSTS FOR SELECTIVE CATALYTIC REDUCTION OF NITRIC OXIDE  

SciTech Connect (OSTI)

Selective catalytic reduction (SCR) of NO{sub x} by hydrocarbons was investigated on Pt doped MCM-41 and copper ion and/or cerium ion-exchanged Al-MCM-41 in the presence of excess oxygen. It was found that Pt/MCM-41 provided the highest specific NO reduction rates as compared with other Pt doped catalysts reported in the literature, such as Pt/Al{sub 2}O{sub 3} and Pt/ZSM-5. For different hydrocarbons, the catalytic activity decreased according to the sequence of C{sub 3}H{sub 6} {approx} C{sub 2}H{sub 4} >> C{sub 3}H{sub 8} > CH{sub 4}. This catalyst was also stable in the presence of H{sub 2}O and SO{sub 2}. Cu exchanged Al-MCM-41 and cerium promoted Cu-Al-MCM-41 (i.e., Ce-Cu-Al-MCM-41) were also found to be active in this reaction. Higher NO{sub x} conversions to N2 were obtained on the Ce-Cu-Al-MCM-41 as compared with Cu-Al-MCM-41. The activity of Ce-Cu-Al-MCM-41 was approximately the same as that of Cu-ZSM-5; but the former had a wider temperature window. TPR results indicated that only isolated Cu{sup 2+} and Cu{sup +} ions were detected in the Cu{sup 2+}-exchanged Al-MCM-41 samples, which may play an important role in the selective catalytic reduction of NO{sub x} to N{sub 2}. After some cerium ions were introduced into Cu-Al-MCM-41, Cu{sup 2+} in the molecular sieve became more easily reducible by H{sub 2}. This may be related to the increase of catalytic activity of NO{sub x} reduction by ethylene.

R. Q. LONG; R.T. YANG

1998-09-30T23:59:59.000Z

20

Selective catalytic reduction system and process using a pre-sulfated zirconia binder  

DOE Patents [OSTI]

A selective catalytic reduction (SCR) process with a palladium catalyst for reducing NOx in a gas, using hydrogen as a reducing agent is provided. The process comprises contacting the gas stream with a catalyst system, the catalyst system comprising (ZrO2)SO4, palladium, and a pre-sulfated zirconia binder. The inclusion of a pre-sulfated zirconia binder substantially increases the durability of a Pd-based SCR catalyst system. A system for implementing the disclosed process is further provided.

Sobolevskiy, Anatoly; Rossin, Joseph A.

2010-06-29T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

HYBRID SELECTIVE NON-CATALYTIC REDUCTION (SNCR)/SELECTIVE CATALYTIC REDUCTION (SCR) DEMONSTRATION FOR THE REMOVAL OF NOx FROM BOILER FLUE GASES  

SciTech Connect (OSTI)

The U. S. Department of Energy (DOE), Electric Power Research Institute (EPRI), Pennsylvania Electric Energy Research Council, (PEERC), New York State Electric and Gas and GPU Generation, Inc. jointly funded a demonstration to determine the capabilities for Hybrid SNCR/SCR (Selective Non-Catalytic Reduction/Selective Catalytic Reduction) technology. The demonstration site was GPU Generation's Seward Unit No.5 (147MW) located in Seward Pennsylvania. The demonstration began in October of 1997 and ended in December 1998. DOE funding was provided through Grant No. DE-FG22-96PC96256 with T. J. Feeley as the Project Manager. EPRI funding was provided through agreements TC4599-001-26999 and TC4599-002-26999 with E. Hughes as the Project Manager. This project demonstrated the operation of the Hybrid SNCR/SCR NO{sub x} control process on a full-scale coal fired utility boiler. The hybrid technology was expected to provide a cost-effective method of reducing NO{sub x} while balancing capital and operation costs. An existing urea based SNCR system was modified with an expanded-duct catalyst to provide increased NO{sub x} reduction efficiency from the SNCR while producing increased ammonia slip levels to the catalyst. The catalyst was sized to reduce the ammonia slip to the air heaters to less than 2 ppm while providing equivalent NO{sub x} reductions. The project goals were to demonstrate hybrid technology is capable of achieving at least a 55% reduction in NO{sub x} emissions while maintaining less than 2ppm ammonia slip to the air heaters, maintain flyash marketability, verify the cost benefit and applicability of Hybrid post combustion technology, and reduce forced outages due to ammonium bisulfate (ABS) fouling of the air heaters. Early system limitations, due to gas temperature stratification, restricted the Hybrid NO{sub x} reduction capabilities to 48% with an ammonia slip of 6.1 mg/Nm{sup 3} (8 ppm) at the catalyst inlet. After resolving the stratification problem, the catalyst did not have sufficient activity in order to continue the planned test program. Arsenic poisoning was found to be the cause of premature catalyst deactivation.

Jerry B. Urbas

1999-05-01T23:59:59.000Z

22

An assessment of Texas wholesale nursery grower and the effect of selected growth retardants on Salvia farinacea x longispicata "Indigo Spires"  

E-Print Network [OSTI]

Record of Study An Assessment of a Texas Wholesale Nursery Grower and The Effect of Selected Growth Retardants on Sal via farinacea x longispicata 'Indigo Spires' A PROFESSIONAL PAPER by David Rodriguez Submitted to the College... of Agriculture of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF AGRICULTURE November, 1992 Department of Horticultural Sciences An Assessment of a Texas Wholesale Nursery Grower and The Effect of Selected...

Rodriguez, David

1992-01-01T23:59:59.000Z

23

Aluminosilicates as controlled molecular environments for selective photochemical and catalytic reactions  

SciTech Connect (OSTI)

This dissertation concerns research that involves photochemical, catalytic and spectroscopic studies of clays, pillared clays and zeolites. Incorporation of uranyl ions into hectorite, montmorillonite, bentonite and vermiculite clays was monitored by XRD and luminescence methods. Excitation and emission characteristics were studied in order to understand the behavior of uranyl ions in clays after various thermal treatments. Luminescence lifetime measurements elucidated the number of uranyl sites. Uranyl-exchanged clays were found to absorb light at lower energies (445-455nm) than analogous uranyl-exchanged zeolites (425nm). Each uranyl-exchanged clay was tested as a catalyst for the photoassisted oxidation of isopropyl alcohol. Energy transfer (ET) between uranyl and Eu(III) ions in different zeolite framework systems was examined. The efficiency of ET (eta/sub t/) was found to be affected by the type of framework present. Pillared bentonites were examined in the hydrocracking of decane. A catalytically and spectroscopically active dopant ion, Cr(III), was introduced into the clays in both pillared and unpillared forms depending upon synthetic conditions. EPR and DRS were employed to monitor the environment of Cr(III) for determination of its location - whether in the micropore structure or associated with alumina pillars. Catalytic behavior based upon this variability of location was examined. Incorporation of Cr(III) ions into an alumina pillar was found to increase the stability and activity with respect to an alumina PILC catalyst. The results of these studies suggest that selective, efficient catalysts can be designed around inorganic ions in aluminosilicate supports.

Carrado, K.A.

1986-01-01T23:59:59.000Z

24

Selective catalytic reduction of sulfur dioxide to elemental sulfur. Final report  

SciTech Connect (OSTI)

This project has investigated new metal oxide catalysts for the single stage selective reduction of SO{sub 2} to elemental sulfur by a reductant, such as CO. Significant progress in catalyst development has been made during the course of the project. We have found that fluorite oxides, CeO{sub 2} and ZrO{sub 2}, and rare earth zirconates such as Gd{sub 2}Zr{sub 2}O{sub 7} are active and stable catalysts for reduction Of SO{sub 2} by CO. More than 95% sulfur yield was achieved at reaction temperatures about 450{degrees}C or higher with the feed gas of stoichiometric composition. Reaction of SO{sub 2} and CO over these catalysts demonstrated a strong correlation of catalytic activity with the catalyst oxygen mobility. Furthermore, the catalytic activity and resistance to H{sub 2}O and CO{sub 2} poisoning of these catalysts were significantly enhanced by adding small amounts of transition metals, such as Co, Ni, Co, etc. The resulting transition metal-fluorite oxide composite catalyst has superior activity and stability, and shows promise in long use for the development of a greatly simplified single-step sulfur recovery process to treat variable and dilute SO{sub 2} concentration gas streams. Among various active composite catalyst systems the Cu-CeO{sub 2} system has been extensively studied. XRD, XPS, and STEM analyses of the used Cu-CeO{sub 2} catalyst found that the fluorite crystal structure of ceria was stable at the present reaction conditions, small amounts of copper was dispersed and stabilized on the ceria matrix, and excess copper oxide particles formed copper sulfide crystals of little contribution to catalytic activity. A working catalyst consisted of partially sulfated cerium oxide surface and partially sulfided copper clusters. The overall reaction kinetics were approximately represented by a first order equation.

Liu, W.; Flytzani-Stephanopoulos, M.; Sarofim, A.F.

1995-06-01T23:59:59.000Z

25

PILLARED CLAYS AS SUPERIOR CATALYSTS FOR SELECTIVE CATALYTIC REDUCTION OF NITRIC OXIDE  

SciTech Connect (OSTI)

Removal of NO{sub x} (NO + NO{sub 2}) from exhaust gases is a challenging subject. V{sub 2}O{sub 5}-based catalysts are commercial catalysts for selective catalytic reduction (SCR) with NH{sub 3} for stationary sources. However, for diesel and lean-burn gasoline engines in vehicles, hydrocarbons would be the preferred reducing agents over NH{sub 3} because of the practical problems associated with the use of NH{sub 3} (i.e., handling and slippage through the reactor). The noble-metal three-way catalysts are not effective under these conditions. The first catalyst found to be active for selective catalytic reduction of NO by hydrocarbons in the presence of excess oxygen was copper exchanged ZSM-5 and other zeolites, reported in 1990 by Iwamoto in Japan and Held et al. in Germany. Although Cu-ZSM-5 is very active and the most intensively studied catalyst, it suffers from severe deactivation in engine tests, mainly due to H{sub 2}O and SO{sub 2}. In this project, we found that ion-exchanged pillared clays and MCM-41 catalysts showed superior SCR activities of NO with hydrocarbon. All Cu{sup 2+}-exchanged pillared clays showed higher SCR activities than Cu-ZSM-5 reported in the literature. In particular, H{sub 2}O and SO{sub 2} only slightly deactivated the SCR activity of Cu-TiO{sub 2}-PILC, whereas severe deactivation was observed for Cu-ZSM-5. Moreover, Pt/MCM-41 provided the highest specific NO reduction rates as compared with other Pt doped catalysts, i.e., Pt/Al{sub 2}O{sub 3}, Pt/SiO{sub 2} and Pt/ZSM-5. The Pt/MCM-41 catalyst also showed a good stability in the presence of H{sub 2}O and SO{sub 2}.

R.Q. Long; N. Tharappiwattananon; W.B. Li; R.T. Yang

2000-09-01T23:59:59.000Z

26

DEVELOPMENT OF IMPROVED CATALYSTS FOR THE SELECTIVE CATALYTIC REDUCTION OF NITROGEN OXIDES WITH HYDROCARBONS  

SciTech Connect (OSTI)

Significant work has been done by the investigators on the cerium oxide-copper oxide based sorbent/catalysts for the combined removal of sulfur and nitrogen oxides from the flue gases of stationary sources. A relatively wide temperature window was established for the use of alumina-supported cerium oxide-copper oxide mixtures as regenerable sorbents for SO{sub 2} removal. Evaluation of these sorbents as catalysts for the selective reduction of NO{sub x} gave promising results with methane. Since the replacement of ammonia by methane is commercially very attractive, in this project, it was planned to investigate the effect of promoters on the activity and selectivity of copper oxide/cerium oxide-based catalysts and to obtain data on the reaction mechanism for the SCR with methane. The investigation of the reaction mechanism will help in the selection of promoters to improve the catalytic activity and selectivity of the sorbents in the SCR with methane. This will result in new catalyst formulations. The last component of the project involves our industrial partner TDA Research, and the objective is to evaluate long- term stability and durability of the prepared sorbent/catalysts. In the second year of the project, the catalysts were investigated for their SCR activity with methane in a microreactor setup and also, by the temperature-programmed desorption (TPD) technique. The results from the SCR experiments indicated that manganese is a more effective promoter than rhodium on the supported copper oxide-ceria catalysts under study; the effectiveness of the promoter increases with the increase in Ce/Cu ratio. The TPD profiles of the unpromoted catalyst (Cu/Ce=3) is different than those promoted with 0.1% rhodium. In the current reporting period, the screening of the promoted catalysts were completed, sufficient amount of the selected catalysts were prepared and delivered to TDA for long term deactivation testing.

Dr. Ates Akyurlu; Dr. Jale F. Akyurtlu

2003-01-28T23:59:59.000Z

27

Superior catalysts for selective catalytic reduction of nitric oxide. Quarterly technical progress report, January 1, 1995--March 31, 1995  

SciTech Connect (OSTI)

During this quarter, progress was made on the following tasks: TPD techniques were employed to study the reaction mechanism of the selective catalytic reduction of nitrogen oxide with ammonia over iron oxide pillared clay catalyst; and a sulfur dioxide resistant iron oxide/titanium oxide catalyst was developed.

Li, W.B.; Yang, R.T.

1995-12-01T23:59:59.000Z

28

Correlations between surface structure and catalytic activity/selectivity. Progress report, January 1, 1994--December 31, 1994  

SciTech Connect (OSTI)

The primary focus of this research is to address those issues which are keys to understanding the relationship between surface properties and catalytic activity/selectivity. These issues also impact the understanding of the origins of the enhanced catalytic properties of mixed-metal catalysts. The experimental approach utilizes a microcatalytic reactor contiguous to a surface analysis system, an arrangement which allows in vacuo transfer of the catalyst from one chamber to the other. Surface techniques being used include Auger (AES), ultraviolet and X-ray photoemission spectroscopy (UPS and XPS), temperature programmed desorption (TPD), low energy electron diffraction (LEED), high resolution electron energy loss spectroscopy (HREELS), infrared reflection absorption spectroscopy (IRAS), and scanning tunneling and atomic force microscopy (STM and AFM). This research program builds upon previous experience relating the results of single crystal kinetic measurements with the results obtained with supported analogs. As well, the authors are exploiting recent work on the preparation, the characterization, and the determination of the catalytic properties of ultra-thin metal and metal oxide films. Specifically, the program is proceeding toward three goals: (1) the study of the unique catalytic properties of ultrathin metal films; (2) the investigation of the critical ensemble size requirements for principal catalytic reaction types; and (3) the modelling of supported catalysts using ultra-thin planar oxide surfaces.

Goodman, D.W.

1994-09-01T23:59:59.000Z

29

Correlations between surface structure and catalytic activity/selectivity. Progress report, January 1, 1992--December 31, 1992  

SciTech Connect (OSTI)

Objective is to address the keys to understanding the relation between surface structure and catalytic activity/selectivity. Of concern are questions related to enhanced catalytic properties of mixed-metal catalysts and critical active site requirements for molecular synthesis and rearrangement. The experimental approach utilizes a microcatalytic reactor contiguous to a surface analysis system, an arrangement which allows in vacuo transfer of the catalyst from one chamber to the other. Surface techniques being used include Auger (AES), UV and X-ray photoemission spectroscopy (UPS and XPS), temperature programmed desorption (TPD), low energy electron diffraction (LEED), high resolution electron energy loss spectroscopy (HREELS) and infrared reflection-absorption spectroscopy (IRAS). Our research program builds upon our previous experience relating the results of single crystal kinetic measurements with the results obtained with supported analogs. As well we are exploiting our recent work on the preparation, the characterization, and the determination of the catalytic properties of ultra-thin metal and metal oxide films. The program is proceeding toward the study of the unique catalytic properties of ultrathin metal films; the investigation of the critical ensemble size requirements for principal catalytic reaction types; and the modelling of supported catalysts using ultra-thin planar oxide surfaces.

Goodman, D.W.

1992-10-01T23:59:59.000Z

30

DEVELOPMENT OF IMPROVED CATALYSTS FOR THE SELECTIVE CATALYTIC REDUCTION OF NITROGEN OXIDES WITH HYDROCARBONS  

SciTech Connect (OSTI)

Significant work has been done by the investigators on the cerium oxide-copper oxide based sorbent/catalysts for the combined removal of sulfur and nitrogen oxides from the flue gases of stationary sources. A relatively wide temperature window was established for the use of alumina-supported cerium oxide-copper oxide mixtures as regenerable sorbents for SO{sub 2} removal. Preliminary evaluation of these sorbents as catalysts for the selective reduction of NO{sub x} gave promising results with ammonia, but indicated low selectivity when methane was used as the reductant. Since the replacement of ammonia by another reductant is commercially very attractive, in this project, four research components will be undertaken. The investigation of the reaction mechanism, the first component, will help in the selection of promoters to improve the catalytic activity and selectivity of the sorbents in the SCR with methane. This will result in new catalyst formulations (second component). If this research is successful, the combined SO{sub 2}-NO{sub x} removal process based on alumina-supported copper oxide-ceria sorbent/catalysts will become very attractive for commercial applications. The objective of the third component of the project is to develop an alternative SCR process using another inexpensive fuel, residual fuel oil, instead of natural gas. This innovative proposal is based on very scant evidence concerning the good performance of coked catalysts in the selective reduction of NO and if proven to work the process will certainly be commercially viable. The fourth component of the project involves our industrial partner TDA Research, and the objective is to evaluate long- term stability and durability of the prepared sorbent/catalysts. In the second year of the project, the catalysts were investigated for their SCR activity with methane in a microreactor setup and also, by the temperature-programmed desorption (TPD) technique. The results from the SCR experiments indicated that manganese is a more effective promoter than rhodium on the supported copper oxide-ceria catalysts under study; the effectiveness of the promoter increases with the increase in Ce/Cu ratio. The TPD profiles of the unpromoted catalyst (Cu/Ce=3) is different than those promoted with 0.1% rhodium.

Ates Akyurtlu; Jale F. Akyurtlu

2001-09-01T23:59:59.000Z

31

DEVELOPMENT OF IMPROVED CATALYSTS FOR THE SELECTIVE CATALYTIC REDUCTION OF NITROGEN OXIDES WITH HYDROCARBONS  

SciTech Connect (OSTI)

Significant work has been done by the investigators on the cerium oxide-copper oxide based sorbent/catalysts for the combined removal of sulfur and nitrogen oxides from the flue gases of stationary sources. A relatively wide temperature window was established for the use of alumina-supported cerium oxide-copper oxide mixtures as regenerable sorbents for SO{sub 2} removal. Preliminary evaluation of these sorbents as catalysts for the selective reduction of NO{sub x} gave promising results with ammonia, but indicated low selectivity when methane was used as the reductant. Since the replacement of ammonia by another reductant is commercially very attractive, in this project, four research components will be undertaken. The investigation of the reaction mechanism, the first component, will help in the selection of promoters to improve the catalytic activity and selectivity of the sorbents in the SCR with methane. This will result in new catalyst formulations (second component). If this research is successful, the combined SO{sub 2}-NO{sub x} removal process based on alumina-supported copper oxide-ceria sorbent/catalysts will become very attractive for commercial applications. The objective of the third component of the project is to develop an alternative SCR process using another inexpensive fuel, residual fuel oil, instead of natural gas. This innovative proposal is based on very scant evidence concerning the good performance of coked catalysts in the selective reduction of NO and if proven to work the process will certainly be commercially viable. The fourth component of the project involves our industrial partner TDA Research, and the objective is to evaluate long-term stability and durability of the prepared sorbent/catalysts. In the first year of the project, the catalysts were investigated by the temperature-programmed reduction (TPR) technique. The results from TPR indicated that the interaction with support appears to promote reduction at lower temperatures. Copper oxide in excess of monolayer coverage reduces at temperatures close to the reduction temperature of the unsupported copper oxide. Increased dispersion increases the support effect. Low activity of ceria in NO reduction may be due to its resistance to reduction at low temperatures.

Dr. Ates Akyurtlu; Dr. Jale F. Akyurtlu

2001-05-31T23:59:59.000Z

32

INVESTIGATION OF AMMONIA ADSORPTION ON FLY ASH DUE TO INSTALLATION OF SELECTIVE CATALYTIC REDUCTION SYSTEMS  

SciTech Connect (OSTI)

This report summarizes an investigation of the potential impacts associated with the utilization of selective catalytic reduction (SCR) systems at coal-fired power plants. The study was sponsored by the U.S. Department of Energy Emission Control By-Products Consortium, Dominion Generation, the University of Kentucky Center for Applied Energy Research and GAI Consultants, Inc. SCR systems are effective in reducing nitrogen oxides (NOx) emissions as required by the Clean Air Act (CAA) Amendments. However, there may be potential consequences associated with ammonia contamination of stack emissions and combustion by-products from these systems. Costs for air quality, landfill and pond environmental compliance may increase significantly and the marketability of ash may be seriously reduced, which, in turn, may also lead to increased disposal costs. The potential impacts to air, surface water, groundwater, ash disposal, ash utilization, health and safety, and environmental compliance can not be easily quantified based on the information presently available. The investigation included: (1) a review of information and data available from published and unpublished sources; (2) baseline ash characterization testing of ash samples produced from several central Appalachian high-volatile bituminous coals from plants that do not currently employ SCR systems in order to characterize the ash prior to ammonia exposure; (3) an investigation of ammonia release from fly ash, including leaching and thermal studies; and (4) an evaluation of the potential impacts on plant equipment, air quality, water quality, ash disposal operations, and ash marketing.

G.F. Brendel; J.E. Bonetti; R.F. Rathbone; R.N. Frey Jr.

2000-11-01T23:59:59.000Z

33

System and method for selective catalytic reduction of nitrogen oxides in combustion exhaust gases  

DOE Patents [OSTI]

A multi-stage selective catalytic reduction (SCR) unit (32) provides efficient reduction of NOx and other pollutants from about 50-550.degree. C. in a power plant (19). Hydrogen (24) and ammonia (29) are variably supplied to the SCR unit depending on temperature. An upstream portion (34) of the SCR unit catalyzes NOx+NH.sub.3 reactions above about 200.degree. C. A downstream portion (36) catalyzes NOx+H.sub.2 reactions below about 260.degree. C., and catalyzes oxidation of NH.sub.3, CO, and VOCs with oxygen in the exhaust above about 200.degree. C., efficiently removing NOx and other pollutants over a range of conditions with low slippage of NH.sub.3. An ammonia synthesis unit (28) may be connected to the SCR unit to provide NH.sub.3 as needed, avoiding transport and storage of ammonia or urea at the site. A carbonaceous gasification plant (18) on site may supply hydrogen and nitrogen to the ammonia synthesis unit, and hydrogen to the SCR unit.

Sobolevskiy, Anatoly; Rossin, Joseph A

2014-04-08T23:59:59.000Z

34

Method of making a catalytic metal oxide selective for the conversion of a gas and a coating system for the selective oxidation of hydrocarbons and carbon monoxide  

SciTech Connect (OSTI)

A method is described of making a catalytic metal oxide selective to catalyzing the conversion of given gas species, comprising: intimately supporting a solid film of catalytic metal oxide on an electrically conducting material, said film having an exposed outer surface spaced no greater than 1,000 angstroms from said conducting material and said conducting material being matched to the composition of said oxide to change the electron state of the exposed outer surface to promote a reaction between given gas species and said oxide, said metal oxide being selected from the group consisting of TiO[sub 2], SnO[sub 2], FeO, SrTiO[sub 3], and CoO, and said conducting material being selected from the group consisting of Au, Pt, TiN, Pd, Rh, Ni, and Co.

Logothetis, E.M.; Soltis, R.E.

1993-07-20T23:59:59.000Z

35

Superior catalysts for selective catalytic reduction of nitric oxide. Quarterly technical progress report, October 1, 1994--December 31, 1994  

SciTech Connect (OSTI)

During the past quarter, progress was made in three tasks. The poisoning effects of alkali metals (as Na{sub 2}O, K{sub 2}0 and Cs{sub 2}O) on iron oxide pillared clay (Fe-Bentonite) catalyst for selective catalytic reduction (SCR) of NO with NH{sub 3} were investigated. The effects of sulfur dioxide and water vapor on the performance of the high activity catalyst, that is, Ce-doped Fe-Bentonite pillared clay (Ce-Fe-Bentonite) were examined. In addition, an iron ion-exchanged titania pillared clay (Ti-PILC) was prepared and its catalytic activity for the SCR of NO with NH{sub 3} was studied, which showed a high activity and a high S0{sub 2} and H{sub 2}0 resistance at high temperatures (i.e., above 400{degree}C).

Li, W.B.; Yang, R.T.

1994-12-31T23:59:59.000Z

36

Simultaneous Removal of NOx and Mercury in Low Temperature Selective Catalytic and Adsorptive Reactor  

SciTech Connect (OSTI)

The results of a 18-month investigation to advance the development of a novel Low Temperature Selective Catalytic and Adsorptive Reactor (LTSCAR), for the simultaneous removal of NO{sub x} and mercury (elemental and oxidized) from flue gases in a single unit operation located downstream of the particulate collectors, are reported. In the proposed LTSCAR, NO{sub x} removal is in a traditional SCR mode but at low temperature, and, uniquely, using carbon monoxide as a reductant. The concomitant capture of mercury in the unit is achieved through the incorporation of a novel chelating adsorbent. As conceptualized, the LTSCAR will be located downstream of the particulate collectors (flue gas temperature 140-160 C) and will be similar in structure to a conventional SCR. That is, it will have 3-4 beds that are loaded with catalyst and adsorbent allowing staged replacement of catalyst and adsorbent as required. Various Mn/TiO{sub 2} SCR catalysts were synthesized and evaluated for their ability to reduce NO at low temperature using CO as the reductant. It has been shown that with a suitably tailored catalyst more than 65% NO conversion with 100% N{sub 2} selectivity can be achieved, even at a high space velocity (SV) of 50,000 h-1 and in the presence of 2 v% H{sub 2}O. Three adsorbents for oxidized mercury were developed in this project with thermal stability in the required range. Based on detailed evaluations of their characteristics, the mercaptopropyltrimethoxysilane (MPTS) adsorbent was found to be most promising for the capture of oxidized mercury. This adsorbent has been shown to be thermally stable to 200 C. Fixed-bed evaluations in the targeted temperature range demonstrated effective removal of oxidized mercury from simulated flue gas at very high capacity ({approx}>58 mg Hg/g adsorbent). Extension of the capability of the adsorbent to elemental mercury capture was pursued with two independent approaches: incorporation of a novel nano-layer on the surface of the chelating mercury adsorbent to achieve in situ oxidation on the adsorbent, and the use of a separate titania-supported manganese oxide catalyst upstream of the oxidized mercury adsorbent. Both approaches met with some success. It was demonstrated that the concept of in situ oxidation on the adsorbent is viable, but the future challenge is to raise the operating capacity beyond the achieved limit of 2.7 mg Hg/g adsorbent. With regard to the manganese dioxide catalyst, elemental mercury was very efficiently oxidized in the absence of sulfur dioxide. Adequate resistance to sulfur dioxide must be incorporated for the approach to be feasible in flue gas. A preliminary benefits analysis of the technology suggests significant potential economic and environmental advantages.

Neville G. Pinto; Panagiotis G. Smirniotis

2006-03-31T23:59:59.000Z

37

Synthesis and Evaluation of Cu-SAPO-34 Catalysts for Ammonia Selective Catalytic Reduction. 1. Aqueous Solution Ion Exchange  

SciTech Connect (OSTI)

SAPO-34 molecular sieves are synthesized using various structure directing agents (SDAs). Cu-SAPO-34 catalysts are prepared via aqueous solution ion exchange. Catalysts are characterized with surface area/pore volume measurements, temperature programmed reduction (TPR), electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectroscopies. Catalytic properties are examined using standard ammonia selective catalytic reduction (NH3-SCR) and ammonia oxidation reactions. During solution ion exchange, different SAPO-34 samples undergo different extent of structural damage via irreversible hydrolysis. Si content within the samples (i.e., Al-O-Si bond density) and framework stress are key factors that affect irreversible hydrolysis. Even using very dilute Cu acetate solutions, it is not possible to generate Cu-SAPO-34 samples with only isolated Cu2+ ions. Small amounts of CuOx species always coexist with isolated Cu2+ ions. Highly active and selective Cu-SAPO-34 catalysts for NH3-SCR are readily generated using this synthesis protocol, even for SAPO-34 samples that degrade substantially during solution ion exchange. High-temperature aging is found to improve the catalytic performance. This is likely due to reduction of intracrystalline mass-transfer limitations via formation of additional porosity in the highly defective SAPO-34 particles formed after ion exchange. The authors gratefully acknowledge the US Department of Energy (DOE), Office of Energy Efficiency and Renewable Energy, Office of Vehicle Technologies for the support of this work. The research described in this paper was performed at the Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the DOE’s Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory (PNNL). PNNL is operated for the US DOE by Battelle Memorial Institute under contract number DE-AC05-76RL01830.

Gao, Feng; Walter, Eric D.; Washton, Nancy M.; Szanyi, Janos; Peden, Charles HF

2013-09-06T23:59:59.000Z

38

The selective catalytic reduction of nitric oxide with ammonia in the presence of oxygen  

E-Print Network [OSTI]

supporting the authors conclusions. Kato, et al. (1981 a) studied the catalytic activity of' iron oxide-titanium oxide catalysts with Fe/Ti atonuc ratios of 1/9 for the NO ? NHs ? Oz reaction. No NqO ivas detected in the reaction products, regardless... of the fact that an excess of oxygen ivas present in each reaction stuay. Nitric oxide and ammonia reacted stoichiometrically, regardless of the oxygen concentration, the space velocity, the temperature or the presence of SOz and HqO. The rate...

Gruber, Karen Ann

1989-01-01T23:59:59.000Z

39

Superior catalysts for selective catalytic reduction of nitric oxide. Quarterly technical progress report, 1 April--30 June 1994  

SciTech Connect (OSTI)

In the last Quarterly Technical Progress Report the authors reported the synthesis and (partial characterization) and SCR (Selective Catalytic Reduction of NO) activity for a delaminated Fe{sub 2}O{sub 3}-pillared clay (Fe{sub 2}O{sub 3}-PILC). The SCR activity for this PILC was substantially higher than that of the commercial-type V{sub 2}O{sub 5} + WO{sub 3}/TiO{sub 2} catalyst. During the past quarter, the authors first completed the characterization of the delaminated Fe{sub 2}O{sub 3}-PILC catalyst. Both physical characterization (micropore probing by adsorption and Moessbauer spectroscopy) and chemical characterization (by IR spectroscopy) were performed. Since the synthesis of this PILC sample was undertaken under a specific set of conditions and it is known that the PILC properties depend strongly on the synthesis conditions, they then proceeded to examine in a systematic manner the dependence of the catalytic properties of the PILC on its synthesis conditions. Four parameters in the synthesis were studied: Fe precursors, pH of the pillaring solution, concentration of the pillaring solution, and the starting clay. Finally, the effect of the Cr{sub 2}O{sub 3} promoter on the SCR activity of the pillar clay was studied. Results are reported.

Chen, J.P.; Li, W.B.; Hausladen, M.C.; Kikkinides, E.S.; Yang, R.T.

1994-09-01T23:59:59.000Z

40

Integrated Biomass Gasification with Catalytic Partial Oxidation for Selective Tar Conversion  

SciTech Connect (OSTI)

Biomass gasification is a flexible and efficient way of utilizing widely available domestic renewable resources. Syngas from biomass has the potential for biofuels production, which will enhance energy security and environmental benefits. Additionally, with the successful development of low Btu fuel engines (e.g. GE Jenbacher engines), syngas from biomass can be efficiently used for power/heat co-generation. However, biomass gasification has not been widely commercialized because of a number of technical/economic issues related to gasifier design and syngas cleanup. Biomass gasification, due to its scale limitation, cannot afford to use pure oxygen as the gasification agent that used in coal gasification. Because, it uses air instead of oxygen, the biomass gasification temperature is much lower than well-understood coal gasification. The low temperature leads to a lot of tar formation and the tar can gum up the downstream equipment. Thus, the biomass gasification tar removal is a critical technology challenge for all types of biomass gasifiers. This USDA/DOE funded program (award number: DE-FG36-O8GO18085) aims to develop an advanced catalytic tar conversion system that can economically and efficiently convert tar into useful light gases (such as syngas) for downstream fuel synthesis or power generation. This program has been executed by GE Global Research in Irvine, CA, in collaboration with Professor Lanny Schmidt's group at the University of Minnesota (UoMn). Biomass gasification produces a raw syngas stream containing H2, CO, CO2, H2O, CH4 and other hydrocarbons, tars, char, and ash. Tars are defined as organic compounds that are condensable at room temperature and are assumed to be largely aromatic. Downstream units in biomass gasification such as gas engine, turbine or fuel synthesis reactors require stringent control in syngas quality, especially tar content to avoid plugging (gum) of downstream equipment. Tar- and ash-free syngas streams are a critical requirement for commercial deployment of biomass-based power/heat co-generation and biofuels production. There are several commonly used syngas clean-up technologies: (1) Syngas cooling and water scrubbing has been commercially proven but efficiency is low and it is only effective at small scales. This route is accompanied with troublesome wastewater treatment. (2) The tar filtration method requires frequent filter replacement and solid residue treatment, leading to high operation and capital costs. (3) Thermal destruction typically operates at temperatures higher than 1000oC. It has slow kinetics and potential soot formation issues. The system is expensive and materials are not reliable at high temperatures. (4) In-bed cracking catalysts show rapid deactivation, with durability to be demonstrated. (5) External catalytic cracking or steam reforming has low thermal efficiency and is faced with problematic catalyst coking. Under this program, catalytic partial oxidation (CPO) is being evaluated for syngas tar clean-up in biomass gasification. The CPO reaction is exothermic, implying that no external heat is needed and the system is of high thermal efficiency. CPO is capable of processing large gas volume, indicating a very compact catalyst bed and a low reactor cost. Instead of traditional physical removal of tar, the CPO concept converts tar into useful light gases (eg. CO, H2, CH4). This eliminates waste treatment and disposal requirements. All those advantages make the CPO catalytic tar conversion system a viable solution for biomass gasification downstream gas clean-up. This program was conducted from October 1 2008 to February 28 2011 and divided into five major tasks. - Task A: Perform conceptual design and conduct preliminary system and economic analysis (Q1 2009 ~ Q2 2009) - Task B: Biomass gasification tests, product characterization, and CPO tar conversion catalyst preparation. This task will be conducted after completing process design and system economics analysis. Major milestones include identification of syngas cleaning requirements for proposed system

Zhang, Lingzhi; Wei, Wei; Manke, Jeff; Vazquez, Arturo; Thompson, Jeff; Thompson, Mark

2011-05-28T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Understanding ammonia selective catalytic reduction kinetics over Cu-SSZ-13 from motion of the Cu ions  

SciTech Connect (OSTI)

Cu-SSZ-13 catalysts with three Si/Al ratios, at 6, 12 and 35, are synthesized with solution ion exchange. Catalysts are characterized with surface area/pore volume measurements, temperature programmed reduction (TPR), and electron paramagnetic resonance (EPR) spectroscopy. Catalytic properties are examined using NO oxidation, ammonia oxidation, and standard ammonia selective catalytic reduction (NH3-SCR) reactions. By varying Si/Al ratios and Cu loadings, it is possible to synthesize catalysts with one dominant type of isolated Cu2+ ion species. Prior to full dehydration of the zeolite catalyst, hydrated Cu2+ ions are found to be very mobile as judged from EPR. NO oxidation is catalyzed by O-bridged Cu-dimer species that form at relatively high Cu loadings and in the presence of O2. For NH3 oxidation and standard SCR reactions, transient Cu-dimers even form at much lower Cu loadings; and these are proposed to be the active sites for reaction temperatures ? 350 °C. These dimer species can be viewed as in equilibrium with monomeric Cu ion complexes. Between ~250 and 350 °C, these moieties become less stable causing SCR reaction rates to decrease. At temperatures above 350 °C and at low Cu loadings, Cu-dimers completely dissociate to regenerate isolated Cu2+ monomers that then locate at ion-exchange sites of the zeolite lattice. At low Cu loadings, these Cu species are the high-temperature active SCR catalytic centers. At high Cu loadings, on the other hand, both Cu-dimers and monomers are highly active in the high temperature kinetic regime, yet Cu-dimers are less selective in SCR. Brönsted acidity is also very important for SCR reactivity in the high-temperature regime. The authors gratefully acknowledge the US Department of Energy (DOE), Energy Efficiency and Renewable Energy, Vehicle Technologies Office for the support of this work. The research described in this paper was performed at the Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the DOE’s Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory (PNNL). PNNL is operated for the US DOE by Battelle.

Gao, Feng; Walter, Eric D.; Kollar, Marton; Wang, Yilin; Szanyi, Janos; Peden, Charles HF

2014-11-01T23:59:59.000Z

42

On the mechanism of NO selective catalytic reduction by hydrocarbons over Cu-ZSM-5 via X-ray absorption spectroscopic study  

SciTech Connect (OSTI)

An understanding of the catalytic mechanism of NO{sub x} reduction is critical for the development of next-generation high-fuel efficiency, low-emission vehicles. This paper compiles the investigations in recent years on the mechanism of NO selective catalytic reduction (SCR) by hydrocarbon over Cu-ZSM-5. The studies were focused on the oxidation state and coordination chemistry of the exchanged Cu as the active site during the catalytic reaction using X-ray absorption spectroscopic (XAS) techniques, mainly XANES and EXAFS. Their experiment demonstrated the existence of a redox mechanism which involves cyclic switching of the oxidation states between Cu(II) and Cu(I) in an oxygen-rich gas mixture under elevated temperature. The authors also observed the coordination structural change of copper ion in ZSM-5 accompanying the change of oxidation state. A correlation between cuprous ion concentration and catalytic activity was found in NO SCR by propene. The impact of another two hydrocarbons, propane and methane, on the copper redox behavior also appears to correlate to catalytic activities in the respective mixtures. Discussions on the nature of the active sites and the mechanism of SCR are presented based on the XAS data analysis. The similarity and difference of the physical properties of copper ion between NO catalytic decomposition and NO SCR are also discussed.

Liu, D.J. [AlliedSignal Inc., Des Plaines, IL (United States)] [AlliedSignal Inc., Des Plaines, IL (United States); Robota, H.J. [ASEC, Tulsa, OK (United States)] [ASEC, Tulsa, OK (United States)

1999-04-08T23:59:59.000Z

43

Selective catalytic reduction of sulfur dioxide to elemental sulfur. Quarterly technical progress report No. 6, October--December 1993  

SciTech Connect (OSTI)

Elemental sulfur recovery from SO{sub 2}-containing gas stream is highly attractive as it produces a salable product and no waste to dispose of. However, commercially available schemes are complex and involve multi-stage reactors, such as, most notably in the Resox (reduction of SO{sub 2} with coke) and Claus plant (reaction of SO{sub 2} with H{sub 2}S over catalyst). This project will investigate a cerium oxide catalyst for the single stage selective reduction of SO{sub 2} to elemental sulfur by a reductant, such as carbon monoxide. Cerium oxide has been identified in recent work at MIT as a superior catalyst for SO{sub 2} reduction by CO to elemental sulfur because its high activity and high selectivity to sulfur over COS over a wide temperature range (400--650{degree}C). The detailed kinetic and parametric studies of SO{sub 2} reduction planned in this work over various CeO{sub 2} formulations will provide the necessary basis for development of a very simplified process, namely that of a single-stage elemental sulfur recovery scheme from variable concentration gas streams. The potential cost- and energy-efficiency benefits from this approach can not be overstated. A first apparent application is treatment of a regenerator off-gases in power plants using regenerative flue gas desulfurization. Such a simple catalytic converter may offer the long-sought ``Claus-alternative`` for coal-fired power plant applications.

Liu, W.; Flytzani-Stephanopoulos, M.; Sarofim, A.F.

1993-12-31T23:59:59.000Z

44

Selective catalytic reduction of sulfur dioxide to elemental sulfur. Quarterly technical progress report No. 4, April--June 1993  

SciTech Connect (OSTI)

Elemental sulfur recovery from SO{sub 2}-containing gas stream is highly attractive as it produces a salable product and no waste to dispose of. However, commercially available schemes are complex and involve multi-stage reactors, such as, most notably in the Resox (reduction of SO{sub 2} with coke) and Claus plant(reaction of SO{sub 2} with H{sub 2}S over catalyst). This project will investigate a cerium oxide catalyst for the single stage selective reduction of SO{sub 2} to elemental sulfur by a reductant, such as carbon monoxide. Cerium oxide has been identified in recent work at MIT as a superior catalyst for SO{sub 2} reduction by CO to elemental sulfur because its high activity and high selectivity to sulfur over COS over a wide temperature range(400--650{degrees}C). The detailed kinetic and parametric studies of SO{sub 2} reduction planned in this work over various CeO{sub 2}-formulations will provide the necessary basis for development of a very simplified process, namely that of a single-stage elemental sulfur recovery scheme from variable concentration gas streams, The potential cost- and energy-efficiency benefits from this approach can not be overstated. A first apparent application is treatment of a regenerator off-gases in power plants using regenerative flue gas desulfurization. Such a simple catalytic converter may offer the long-sought ``Claus-alternative`` for coal-fired power plant applications.

Liu, Wei; Flytzani-Stephanopoulos, M.; Sarofim, A.F.; Williams, R.S.

1993-12-31T23:59:59.000Z

45

Selective catalytic reduction of nitric oxide with ethanol/gasoline blends over a silver/alumina catalyst  

SciTech Connect (OSTI)

Lean gasoline engines running on ethanol/gasoline blends and equipped with a silver/alumina catalyst for selective catalytic reduction (SCR) of NO by ethanol provide a pathway to reduced petroleum consumption through both increased biofuel utilization and improved engine efficiency relative to the current stoichiometric gasoline engines that dominate the U.S. light duty vehicle fleet. A pre-commercial silver/alumina catalyst demonstrated high NOx conversions over a moderate temperature window with both neat ethanol and ethanol/gasoline blends containing at least 50% ethanol. Selectivity to NH3 increases with HC dosing and ethanol content in gasoline blends, but appears to saturate at around 45%. NO2 and acetaldehyde behave like intermediates in the ethanol SCR of NO. NH3 SCR of NOx does not appear to play a major role in the ethanol SCR reaction mechanism. Ethanol is responsible for the low temperature SCR activity observed with the ethanol/gasoline blends. The gasoline HCs do not deactivate the catalyst ethanol SCR activity, but they also do not appear to be significantly activated by the presence of ethanol.

Pihl, Josh A [ORNL] [ORNL; Toops, Todd J [ORNL] [ORNL; Fisher, Galen [University of Michigan] [University of Michigan; West, Brian H [ORNL] [ORNL

2014-01-01T23:59:59.000Z

46

DEVELOPMENT OF IMPROVED CATALYSTS FOR THE SELECTIVE CATALYTIC REDUCTION OF NITROGEN OXIDES WITH HYDROCARBONS  

SciTech Connect (OSTI)

Significant work has been done by the investigators on the cerium oxide-copper oxide based sorbent/catalysts for the combined removal of sulfur and nitrogen oxides from the flue gases of stationary sources. Evaluation of these sorbents as catalysts for the selective reduction of NO{sub x} gave promising results with methane. Since the replacement of ammonia by methane is commercially very attractive, in this project, the effect of promoters on the activity and selectivity of copper oxide/cerium oxide-based catalysts and the reaction mechanism for the SCR with methane was investigated. Unpromoted and promoted catalysts were investigated for their SCR activity with methane in a microreactor setup and also, by the temperature-programmed desorption (TPD) technique. The results from the SCR experiments indicated that manganese is a more effective promoter than the other metals (Rh, Li, K, Na, Zn, and Sn) for the supported copper oxide-ceria catalysts under study. The effectiveness of the promoter increased with the increase in Ce/Cu ratio. Among the catalysts tested, the Cu1Ce3 catalyst promoted with 1 weight % Mn was found to be the best catalyst for the SCR of NO with methane. This catalyst was subjected to long-term testing at the facilities of our industrial partner TDA Research. TDA report indicated that the performance of this catalyst did not deteriorate during 100 hours of operation and the activity and selectivity of the catalyst was not affected by the presence of SO{sub 2}. The conversions obtained by TDA were significantly lower than those obtained at Hampton University due to the transport limitations on the reaction rate in the TDA reactor, in which 1/8th inch pellets were used while the Hampton University reactor contained 250-425-{micro}m catalyst particles. The selected catalyst was also tested at the TDA facilities with high-sulfur heavy oil as the reducing agent. Depending on the heavy oil flow rate, up to 100% NO conversions were obtained. The temperature programmed desorption studies a strong interaction between manganese and cerium. Presence of manganese not only enhanced the reduction rate of NO by methane, but also significantly improved the N{sub 2} selectivity. To increase the activity of the Mn-promoted catalyst, the manganese content of the catalyst need to be optimized and different methods of catalyst preparation and different reactor types need to be investigated to lower the transport limitations in the reactor.

Ates Akyurtlu; Jale F. Akyurtlu

2003-11-30T23:59:59.000Z

47

Chapter 8: Selective Stoichiometric and Catalytic Reactivity in the Confines of a Chiral Supramolecular Assembly  

SciTech Connect (OSTI)

Nature uses enzymes to activate otherwise unreactive compounds in remarkable ways. For example, DNases are capable of hydrolyzing phosphate diester bonds in DNA within seconds,[1-3]--a reaction with an estimated half-life of 200 million years without an enzyme.[4] The fundamental features of enzyme catalysis have been much discussed over the last sixty years in an effort to explain the dramatic rate increases and high selectivities of enzymes. As early as 1946, Linus Pauling suggested that enzymes must preferentially recognize and stabilize the transition state over the ground state of a substrate.[5] Despite the intense study of enzymatic selectivity and ability to catalyze chemical reactions, the entire nature of enzyme-based catalysis is still poorly understood. For example, Houk and co-workers recently reported a survey of binding affinities in a wide variety of enzyme-ligand, enzyme-transition-state, and synthetic host-guest complexes and found that the average binding affinities were insufficient to generate many of the rate accelerations observed in biological systems.[6] Therefore, transition-state stabilization cannot be the sole contributor to the high reactivity and selectivity of enzymes, but rather, other forces must contribute to the activation of substrate molecules. Inspired by the efficiency and selectivity of Nature, synthetic chemists have admired the ability of enzymes to activate otherwise unreactive molecules in the confines of an active site. Although much less complex than the evolved active sites of enzymes, synthetic host molecules have been developed that can carry out complex reactions with their cavities. While progress has been made toward highly efficient and selective reactivity inside of synthetic hosts, the lofty goal of duplicating enzymes specificity remains.[7-9] Pioneered by Lehn, Cram, Pedersen, and Breslow, supramolecular chemistry has evolved well beyond the crown ethers and cryptands originally studied.[10-12] Despite the increased complexity of synthetic host molecules, most assembly conditions utilize self-assembly to form complex highly-symmetric structures from relatively simple subunits. For supramolecular assemblies able to encapsulate guest molecules, the chemical environment in each assembly--defined by the size, shape, charge, and functional group availability--greatly influences the guest-binding characteristics.[6, 13-17

University of California, Berkeley; Lawrence Berkeley National Laboratory; Raymond, Kenneth; Pluth, Michael D.; Bergman, Robert G.; Raymond, Kenneth N.

2007-09-27T23:59:59.000Z

48

High temperature synthetic cement retarder  

SciTech Connect (OSTI)

A synthetic cement retarder which provides excellent retardation and compressive strength development has been synthesized. The response properties and temperature ranges of the synthetic retarder far exceed those of commonly used retarders such as lignosulfonates. The chemical nature of the new retarder is discussed and compared to another synthetic retarder.

Eoff, L.S.; Buster, D.

1995-11-01T23:59:59.000Z

49

Superior catalysts for selective catalytic reduction of nitric oxide. Annual technical report, September 30, 1993--September 29, 1994  

SciTech Connect (OSTI)

A delaminated Fe{sub 2}O{sub 3}-pillared clay catalyst was prepared for the selective catalytic reduction (SCR) of NO by NH{sub 3} at above 300{degrees}C. The delaminated pillard clay was characterized by ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectroscopy) chemical analysis, XRD (X-ray diffraction) structure and line broadening analyses, micropore size probing, and Moessbauer analysis. These analyses showed that the catalyst contained fragmented Fe{sub 2}O{sub 3}-pillared clay forming {open_quotes}house-of-cards{close_quotes} structure with dispersed Fe{sub 2}O{sub 3} particles approximately 170 {angstrom} in size. The SCR activity of the delaminated pillard clay was higher than the commercial-type V{sub 2}O{sub 5} + WO{sub 3}/TiO{sub 2} catalyst, and also higher than the undelaminated pillard clay and supported Fe{sub 2}O{sub 3} catalysts, under conditions with SO{sub 2}. Infrared measurements of adsorbed NH{sub 3} showed strong Bronsted acidity which was caused possibly by interactions between Fe{sub 2}O{sub 3} and clay.

Chen, J.P.; Hausladen, M.C.; Yang, R.T.

1995-03-01T23:59:59.000Z

50

Clean coal technology: selective catalytic reduction (SCR) technology for the control of nitrogen oxide emissions from coal-fired boilers  

SciTech Connect (OSTI)

The report discusses a project carried out under the US Clean Coal Technology (CCT) Demonstration Program which demonstrated selective catalytic reduction (SCR) technology for the control of NOx emissions from high-sulphur coal-fired boilers under typical boilers conditions in the United States. The project was conducted by Southern Company Services, Inc., who served as a co-funder and as the host at Gulf Power Company's Plant Crist. The SCR process consists of injecting ammonia (NH{sub 3}) into boiler flue gas and passing the flue gas through a catalyst bed where the Nox and NH{sub 3} react to form nitrogen and water vapor. The results of the CCTDP project confirmed the applicability of SCR for US coal-fired power plants. In part as a result of the success of this project, a significant number of commercial SCR units have been installed and are operating successfully in the United States. By 2007, the total installed SCR capacity on US coal-fired units will number about 200, representing about 100,000 MWe of electric generating capacity. This report summarizes the status of SCR technology. 21 refs., 3 figs., 2 tabs., 10 photos.

NONE

2005-05-01T23:59:59.000Z

51

Selective catalytic reduction of sulfur dioxide to elemental sulfur. Quarterly technical progress report No. 6, October 1993--December 1993  

SciTech Connect (OSTI)

Elemental sulfur recovery from SO{sub 2}-containing gas stream is highly attractive as it produces a salable product and no waste to dispose of. However, commercially available schemes are complex and involve multi-stage reactors, such as, most notably in the Resox (reduction of SO{sub 2} with coke) and Claus plant (reaction of SO{sub 2} with H{sub 2}S over catalyst). This project will investigate a cerium oxide catalyst for the single stage selective reduction of SO{sub 2} to elemental sulfur by a reductant, such as carbon monoxide. Cerium oxide has been identified in recent work at MIT as a superior catalyst for SO{sub 2} reduction by CO to elemental sulfur because its high activity and high selectivity to sulfur over COS over a wide temperature range(400-650 {degrees}C). The detailed kinetic and parametric studies of SO{sub 2} reduction planned in this work over various CeO{sub 2}-formulations will provide the necessary basis for development of a very simplified process, namely that of a single-stage elemental sulfur recovery scheme from variable concentration gas streams. The potential cost- and energy-efficiency benefits from this approach can not be overstated. A first apparent application is treatment of a regenerator off-gases in power plants using regenerative flue gas desulfurization. Such a simple catalytic converter may offer the long-sought {open_quotes}Claus-alternative{close_quotes} for coal-fired power plant applications.

Liu, W.; Flytzani-Stephanopoulos, M.; Sarofim, A.F.

1996-01-01T23:59:59.000Z

52

Superior catalysts for selective catalytic reduction of nitric oxide. Quarterly technical progress report, 1 January 1994--31 March 1994  

SciTech Connect (OSTI)

During the past quarter, progress has been made in four tasks as summarized below: Task 1: A delaminated Fe{sub 2}O{sub 3} pillared clay was synthesized and carefully characterized. The chemical composition was measured by ICP atomic emission spectrometry. The structural changes in the clay as well as the iron oxide particle sizes were characterized by X-ray diffraction techniques. Task 2: The Selective Catalytic Reduction (SCR, i.e., NO reduction with NH{sub 3}) activities of the delaminated pillared clay were tested and compared with four other most active SCR catalysts: a commercial V{sub 2}O{sub 5} + WO{sub 3}/TiO{sub 2} catalyst, a Fe{sub 2}O{sub 3}-pillared clay, and two supported Fe{sub 2}O{sub 3} catalysts (on Al{sub 2}O{sub 3} and TiO{sub 2}). The delaminated Fe{sub 2}O{sub 3} pillared clay exhibited the highest SCR activities. Catalyst stability test showed that the delaminated sample was also stable. Task 3: To further increase the SCR activity of the delaminated pillared clay, Cr{sub 2}O{sub 3} was doped as a promoter by incipient wetness. Task 4: Deactivation effects of SO{sub 2} and H{sub 2}O on the SCR activities of the delaminated Fe{sub 2}O{sub 3} pillared clay were studied, and compared with other SCR catalysts. The delaminated clay catalyst showed the least deactivation.

Chen, J.P.; Cheng, L.S.; Hausladen, M.C.; Kikkinides, E.S.; Yang, R.T.

1994-05-01T23:59:59.000Z

53

Superior catalysts for selective catalytic reduction of nitric oxide. Final technical report, October 1, 1993--September 30, 1995  

SciTech Connect (OSTI)

The most advanced and proven technology for NO{sub x} control for stationary sources is Selective Catalytic Reduction (SCR). In SCR, NO{sub x} is reduced by NH{sub 3} to N{sub 2} and H{sub 2}O. The commercial catalysts are based on V{sub 2}O{sub 5}/TiO{sub 2}, and the vanadium-based catalysts are patented by the Japanese (Mitsubishi). However, there are three main advantages for the vanadium-based SCR catalyst: (a) a tendency to be poisoned in the flue gas; (b) oxidation of SO{sub 2} to SO{sub 3} by V{sub 2}O{sub 5}, this is a particularly severe problem due to the higher sulfur content of American coals compared with coals used in Japan (from Australia) and in Europe; (c) environmental problems involved in the disposal of the spent catalyst (due to the toxicity of vanadium). In order to overcome these problems, in addition to the undesirable dominance by the Japanese patent position, the authors have studied in this project a new type of catalyst for the SCR reaction; namely, pillared clays, which have adjustable, unique structures and acidity. Three types of catalysts were developed and tested for this reaction, i.e. Fe{sub 2}O{sub 3}-pillared clays, delaminated Fe{sub 2}O{sub 3}-pillared clays, and ion-exchanged pillared clays. The project was divided into sixteen tasks, and will be reported as such.

Yang, R.T.; Li, W.B.; Chen, J.P.; Hausladen, M.C.; Cheng, L.S.; Kikkinides, E.S.

1995-12-31T23:59:59.000Z

54

Effect of Pt promotion on Ni/Al{sub 2}O{sub 3} for the selective catalytic reduction of NO with hydrogen  

SciTech Connect (OSTI)

Ni/Al{sub 2}O{sub 3} (10 wt.% Ni) and Ni-Pt/Al{sub 2}O{sub 3} (10 wt.% Ni, 0.5 wt.% Pt) were comparatively tested in the hydrogen selective catalytic reduction process (H{sub 2}-SCR), at reaction temperatures below 350°C. Catalytic activity tests consisted in temperature programmed reactions (TPRea) under plug flow conditions from 50 to 350°C, with a temperature rate of 5°C/min, using a feed stream with a reactant ratio NO:H{sub 2}?=?1:1.3 and a GHSV of 4500 h{sup ?1}. Promotion with Pt increases the catalytic performances of the Ni based catalyst, in respect to NO conversion, N{sub 2} selectivity and N{sub 2} yield. The reaction temperatures for NO conversion above 95% decrease significantly due to Pt addition, from 250°C for Ni/Al{sub 2}O{sub 3} to 125°C for Ni-Pt/Al{sub 2}O{sub 3}. Characterization of catalysts was performed by: X ray powder diffraction (XRD) for the estimation of Ni crystallite size, temperature programmed reduction (TPR) for the catalyst reducibility, temperature programmed desorption of hydrogen (H{sub 2}-TPD) for the investigation of active sites and metal dispersion on the support, N{sub 2} adsorption-desorption isotherms at ?196°C for the determination of total specific surface area and pore size distribution, and H/D isotopic exchange on the catalyst surface.

Mihet, Maria, E-mail: maria.mihet@itim-cj.ro; Lazar, Mihaela D., E-mail: maria.mihet@itim-cj.ro; Borodi, G., E-mail: maria.mihet@itim-cj.ro; Almasan, V., E-mail: maria.mihet@itim-cj.ro [National Institute for Research and Development of Isotopic and Molecular Technologies-INCDTIM, 65-103 Donath Str., 400293 Cluj-Napoca (Romania)

2013-11-13T23:59:59.000Z

55

Iron oxide and chromia supported on titania-pillared clay for selective catalytic reduction of nitric oxide with ammonia  

SciTech Connect (OSTI)

TiO{sub 2}-pillard clay (PILC) with high surface area, large pore volume, and large interlayer spacing was used as the support for mixed Fe{sub 2}O{sub 3} and Cr{sub 2}O{sub 3} as the catalyst for selective catalytic reduction (SCR) of NO with NH{sub 3}. The Fe/Cr ratio was varied at a fixed total amount of oxide dopant of 10% (wt). The Fe-Cr/TiO{sub 2}-PILC with Fe/Cr=3 showed the highest activity. Compared with commercial V{sub 2}O{sub 5}/TiO{sub 2} catalysts, the activity (on a per gram basis) of the doped pillared clay was approximately twice as high under H{sub 2}O- and SO{sub 2}-free conditions and was approximately 40% higher under conditions with H{sub 2}O and SO{sub 2}. In addition, its activity for SO{sub 2} oxidation was only 20%-25% of that of the V{sub 2}O{sub 5}-based catalysts. TPD of NH{sub 3} on the Fe-Cr/TiO{sub 2}-PILC catalyst showed that both M=O and M-OH (M=Fe or Cr) were necessary for the SCR reaction. In situ IR spectra of NH{sub 3} showed that there was a higher Bronsted acidity than the Lewis acidity on the surface under reaction conditions and that there existed a direct correlation between the SCR activity and the Bronsted acidity among pillared clays with different Fe/Cr ratios. These results, along with the transient response to O{sub 2}, indicated that a similar mechanism to that on the V{sub 2}O{sub 5} catalyst was operative. The TiO{sub 2}-pillared clay used as the support also contributed to the high activity of the Fe-Cr catalyst. The TiO{sub 2} pillars combined with the tetrahedral SiO{sub 2} surfaces of the clay apparently gave rise to a high dispersion of Fe{sub 2}O{sub 3}. 52 refs., 10 figs., 5 tabs.

Cheng, L.S.; Yang, R.T. [State Univ. of New York, Buffalo, NY (United States)] [State Univ. of New York, Buffalo, NY (United States); Ning Chen [Univ. of Michigan, Ann Arbor, MI (United States)] [Univ. of Michigan, Ann Arbor, MI (United States)

1996-11-01T23:59:59.000Z

56

Correlating catalytic methanol oxidation with the structure and oxidation state of size-1 selected Pt nanoparticles2  

E-Print Network [OSTI]

in the performance of direct methanol fuel cells (DMFC), which produce electricity from11 liquid fuel without1 Correlating catalytic methanol oxidation with the structure and oxidation state of size-1 * Corresponding author: roldan@ucf.edu9 Keywords: platinum; methanol oxidation; operando; XAS; EXAFS; alumina

Kik, Pieter

57

Demonstration of selective catalytic reduction (SCR) technology for the control of nitrogen oxide (NOx) emissions from high-sulfur coal-fired boilers  

SciTech Connect (OSTI)

The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from US, Japanese and European catalyst suppliers on a high-sulfur US coal-fired boiler. SCR is a post-combustion nitrogen oxide (NO{sub x}) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NO{sub x} to convert it to nitrogen and water vapor.

Not Available

1991-11-01T23:59:59.000Z

58

Selective catalytic reduction system and process for treating NOx emissions using a palladium and rhodium or ruthenium catalyst  

SciTech Connect (OSTI)

A process for the catalytic reduction of nitrogen oxides (NOx) in a gas stream (29) in the presence of H.sub.2 is provided. The process comprises contacting the gas stream with a catalyst system (38) comprising zirconia-silica washcoat particles (41), a pre-sulfated zirconia binder (44), and a catalyst combination (40) comprising palladium and at least one of rhodium, ruthenium, or a mixture of ruthenium and rhodium.

Sobolevskiy, Anatoly (Orlando, FL); Rossin, Joseph A. (Columbus, OH); Knapke, Michael J. (Columbus, OH)

2011-07-12T23:59:59.000Z

59

Catalytic nanoporous membranes  

DOE Patents [OSTI]

A nanoporous catalytic membrane which displays several unique features Including pores which can go through the entire thickness of the membrane. The membrane has a higher catalytic and product selectivity than conventional catalysts. Anodic aluminum oxide (AAO) membranes serve as the catalyst substrate. This substrate is then subjected to Atomic Layer Deposition (ALD), which allows the controlled narrowing of the pores from 40 nm to 10 nm in the substrate by deposition of a preparatory material. Subsequent deposition of a catalytic layer on the inner surfaces of the pores reduces pore sizes to less than 10 nm and allows for a higher degree of reaction selectivity. The small pore sizes allow control over which molecules enter the pores, and the flow-through feature can allow for partial oxidation of reactant species as opposed to complete oxidation. A nanoporous separation membrane, produced by ALD is also provided for use in gaseous and liquid separations. The membrane has a high flow rate of material with 100% selectivity. Also provided is a method for producing a catalytic membrane having flow-through pores and discreet catalytic clusters adhering to the inside surfaces of the pores.

Pellin, Michael J; Hryn, John N; Elam, Jeffrey W

2013-08-27T23:59:59.000Z

60

5, 35333559, 2005 Catalytic conversion  

E-Print Network [OSTI]

measurement technique, employing selective gas- phase catalytic conversion of methanol to formaldehyde it the second most abundant organic trace gas after methane. Methanol can play an important role in upper tropoACPD 5, 3533­3559, 2005 Catalytic conversion of methanol to formaldehyde S. J. Solomon et al. Title

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Catalytic coal liquefaction process  

DOE Patents [OSTI]

An improved process for catalytic solvent refining or hydroliquefaction of non-anthracitic coal at elevated temperatures under hydrogen pressure in a solvent comprises using as catalyst a mixture of a 1,2- or 1,4-quinone and an alkaline compound, selected from ammonium, alkali metal, and alkaline earth metal oxides, hydroxides or salts of weak acids. 1 fig.

Garg, D.; Sunder, S.

1986-12-02T23:59:59.000Z

62

Catalytic coal liquefaction process  

DOE Patents [OSTI]

An improved process for catalytic solvent refining or hydroliquefaction of non-anthracitic coal at elevated temperatures under hydrogen pressure in a solvent comprises using as catalyst a mixture of a 1,2- or 1,4-quinone and an alkaline compound, selected from ammonium, alkali metal, and alkaline earth metal oxides, hydroxides or salts of weak acids.

Garg, Diwakar (Macungie, PA); Sunder, Swaminathan (Allentown, PA)

1986-01-01T23:59:59.000Z

63

Process for retarding fluid flow  

SciTech Connect (OSTI)

A process is described for retarding the flow of fluid in a subterranean formation, comprising: (a) introducing an effective amount of a gel-forming composition into a subterranean formation, the gel-forming composition being operable when gelled in the formation for retarding the flow of fluid therein. The gel-forming composition consists of: i. a first substance dissolved in water to form an aqueous solution, the first substance being selected from the group consisting of polyvivyl alcohols, and mixtures thereof, wherein the gel-forming composition contains an amount of the first substance of from about 0.5 to about 5 weight percent of the gel-forming composition, and ii. an effective amount of glutaraldehyde which is operable for forming a weakly acidic condition having a pH from about 5.5 to less than 7 in the gel-forming composition and also operable for promoting crosslinking of the first substance and glutaraldehyde and for forming a gel from the gel-forming composition under the weakly acidic condition within a period of time no greater than about 5 days without adding an acidic catalyst to the gel-forming composition to lower the pH of the gel-forming composition below about 5.5.

Sandford, B.B.; Zillmer, R.C.

1989-01-10T23:59:59.000Z

64

Plasma-assisted catalytic reduction system  

DOE Patents [OSTI]

Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO{sub x} reduction in oxygen-rich vehicle engine exhausts. 8 figs.

Vogtlin, G.E.; Merritt, B.T.; Hsiao, M.C.; Wallman, P.H.; Penetrante, B.M.

1998-01-27T23:59:59.000Z

65

Selective Catalytic Reduction (SCR) of nitric oxide with ammonia using Cu-ZSM-5 and Va-based honeycomb monolith catalysts: effect of H2 pretreatment, NH3-to-NO ratio, O2, and space velocity  

E-Print Network [OSTI]

In this work, the steady-state performance of zeolite-based (Cu-ZSM-5) and vanadium-based honeycomb monolith catalysts was investigated in the selective catalytic reduction process (SCR) for NO removal using NH3. The aim was to delineate the effect...

Gupta, Saurabh

2004-09-30T23:59:59.000Z

66

Study of mercury oxidation by a selective catalytic reduction catalyst in a pilot-scale slipstream reactor at a utility boiler burning bituminous coal  

SciTech Connect (OSTI)

One of the cost-effective mercury control technologies in coal-fired power plants is the enhanced oxidation of elemental mercury in selective catalytic reduction (SCR) followed by the capture of the oxidized mercury in the wet scrubber. This paper is the first in a series of two in which the validation of the SCR slipstream test and Hg speciation variation in runs with or without SCR catalysts inside the SCR slipstream reactor under special gas additions (HCl, Cl{sub 2}, SO{sub 2}, and SO{sub 3}) are presented. Tests indicate that the use of a catalyst in a SCR slipstream reactor can achieve greater than 90% NO reduction efficiency with a NH{sub 3}/NO ratio of about 1. There is no evidence to show that the reactor material affects mercury speciation. Both SCR catalysts used in this study exhibited a catalytic effect on the elemental mercury oxidation but had no apparent adsorption effect. SCR catalyst 2 seemed more sensitive to the operational temperature. The spike gas tests indicated that HCl can promote Hg{sup 0} oxidation but not Cl{sub 2}. The effect of Cl{sub 2} on mercury oxidation may be inhibited by higher concentrations of SO{sub 2}, NO, or H{sub 2}O in real flue-gas atmospheres within the typical SCR temperature range (300-350{sup o}C). SO{sub 2} seemed to inhibit mercury oxidation; however, SO{sub 3} may have some effect on the promotion of mercury oxidation in runs with or without SCR catalysts. 25 refs., 9 figs., 2 tabs.

Yan Cao; Bobby Chen; Jiang Wu; Hong Cui; John Smith; Chi-Kuan Chen; Paul Chu; Wei-Ping Pan [Western Kentucky University, Bowling Green, KY (United States). Institute for Combustion Science and Environmental Technology (ICSET)

2007-01-15T23:59:59.000Z

67

Selective catalytic reduction of nitrogen oxides by ammonia over Fe{sup 3+}-exchanged TiO{sub 2}-pillared clay catalysts  

SciTech Connect (OSTI)

Fe-exchanged TiO{sub 2}-pillared clay (PILC) catalysts were prepared and used for selective catalytic reduction (SCR) of NO{sub x} by ammonia. They were also characterized for surface area, pore size distribution, and by XRD, H{sub 2}-TPR, and FT-IR methods. The Fe-TiO{sub 2}-PILC catalysts showed high activities in the reduction of NO{sub x} by NH{sub 3} in the presence of excess oxygen. SO{sub 2} further increased the catalytic activities at above 350 C, whereas H{sub 2}O decreased the activity slightly. The catalysts were about twice as active as commercial-type V{sub 2}O{sub 5}-WO{sub 3}/TiO{sub 2} catalyst in the presence of H{sub 2}O and SO{sub 2}. Moreover, compared to the commercial catalyst, the Fe-TiO{sub 2}-PILC catalysts had higher N{sub 2}/N{sub 2}O product selectivities (e.g., 0--1% vs 9% N{sub 2}O at 400 C) and substantially lower activities (by 74--88%) for SO{sub 2} oxidation to SO{sub 3} under the same reaction conditions. The activity was further increased to over three times that of the vanadia-based catalyst when Ce was added. The high activity and low N{sub 2}O selectivity for the Fe-TiO{sub 2}-PILC catalysts were attributed to their low activity in the oxidation of ammonia, as compared with vanadia catalysts. XRD patterns of Fe-TiO{sub 2}-PILC were similar to those of TiO{sub 2}-PILC, showing no peaks due to iron oxide, even when the iron content reached 20.1%. The TPR results indicated that iron in the Fe-TiO{sub 2}-PILC catalysts with lower iron contents existed in the form of isolated Fe{sup 3+} ions. The activities of Fe-TiO{sub 2}-PILC catalysts were consistent with their surface acidities, which were identified by FT-IR of the NH{sub 3}-adsorbed samples. The enhancement of activities by H{sub 2}O + SO{sub 2} was attributed to the increase of surface acidity resulting from the formation of surface sulfate species of iron.

Long, R.Q.; Yang, R.T. [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Chemical Engineering] [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Chemical Engineering

1999-09-10T23:59:59.000Z

68

Accelerating and Retarding Anomalous Diffusion  

E-Print Network [OSTI]

In this paper Gaussian models of retarded and accelerated anomalous diffusion are considered. Stochastic differential equations of fractional order driven by single or multiple fractional Gaussian noise terms are introduced to describe retarding and accelerating subdiffusion and superdiffusion. Short and long time asymptotic limits of the mean squared displacement of the stochastic processes associated with the solutions of these equations are studied. Specific cases of these equations are shown to provide possible descriptions of retarding or accelerating anomalous diffusion.

Chai Hok Eab; S. C. Lim

2012-01-14T23:59:59.000Z

69

Partitioning of mercury, arsenic, selenium, boron, and chloride in a full-scale coal combustion process equipped with selective catalytic reduction, electrostatic precipitation, and flue gas desulfurization systems  

SciTech Connect (OSTI)

A full-scale field study was carried out at a 795 MWe coal-fired power plant equipped with selective catalytic reduction (SCR), an electrostatic precipitator (ESP), and wet flue gas desulfurization (FGD) systems to investigate the distribution of selected trace elements (i.e., mercury, arsenic, selenium, boron, and chloride) from coal, FGD reagent slurry, makeup water to flue gas, solid byproduct, and wastewater streams. Flue gases were collected from the SCR outlet, ESP inlet, FGD inlet, and stack. Concurrent with flue gas sampling, coal, bottom ash, economizer ash, and samples from the FGD process were also collected for elemental analysis. By combining plant operation parameters, the overall material balances of selected elements were established. The removal efficiencies of As, Se, Hg, and B by the ESP unit were 88, 56, 17, and 8%, respectively. Only about 2.5% of Cl was condensed and removed from flue gas by fly ash. The FGD process removed over 90% of Cl, 77% of B, 76% of Hg, 30% of Se, and 5% of As. About 90% and 99% of the FGD-removed Hg and Se were associated with gypsum. For B and Cl, over 99% were discharged from the coal combustion process with the wastewater. Mineral trona (trisodium hydrogendicarbonate dehydrate, Na{sub 3}H(CO{sub 3}){sub 2}.2H{sub 2}O) was injected before the ESP unit to control the emission of sulfur trioxide (SO{sub 3}). By comparing the trace elements compositions in the fly ash samples collected from the locations before and after the trona injection, the injection of trona did not show an observable effect on the partitioning behaviors of selenium and arsenic, but it significantly increased the adsorption of mercury onto fly ash. The stack emissions of mercury, boron, selenium, and chloride were for the most part in the gas phase. 47 refs., 3 figs., 11 tabs.

Chin-Min Cheng; Pauline Hack; Paul Chu; Yung-Nan Chang; Ting-Yu Lin; Chih-Sheng Ko; Po-Han Chiang; Cheng-Chun He; Yuan-Min Lai; Wei-Ping Pan [Western Kentucky University, Bowling Green, KY (United States). Institute for Combustion Science and Environmental Technology

2009-09-15T23:59:59.000Z

70

Shape-selective catalysts for Fischer-Tropsch chemistry : atomic layer deposition of active catalytic metals. Activity report : January 1, 2005 - September 30, 2005.  

SciTech Connect (OSTI)

Argonne National Laboratory is carrying out a research program to create, prepare, and evaluate catalysts to promote Fischer-Tropsch (FT) chemistry - specifically, the reaction of hydrogen with carbon monoxide to form long-chain hydrocarbons. In addition to needing high activity, it is desirable that the catalysts have high selectivity and stability with respect to both mechanical strength and aging properties. The broad goal is to produce diesel fraction components and avoiding excess yields of both light hydrocarbons and heavy waxes. Originally the goal was to prepare shape-selective catalysts that would limit the formation of long-chain products and yet retain the active metal sites in a protected 'cage.' Such catalysts were prepared with silica-containing fractal cages. The activity was essentially the same as that of catalysts without the cages. We are currently awaiting follow-up experiments to determine the attrition strength of these catalysts. A second experimental stage was undertaken to prepare and evaluate active FT catalysts formed by atomic-layer deposition [ALD] of active components on supported membranes and particulate supports. The concept was that of depositing active metals (i.e. ruthenium, iron or cobalt) upon membranes with well defined flow channels of small diameter and length such that the catalytic activity and product molecular weight distribution could be controlled. In order to rapidly evaluate the catalytic membranes, the ALD coating processes were performed in an 'exploratory mode' in which ALD procedures from the literature appropriate for coating flat surfaces were applied to the high surface area membranes. Consequently, the Fe and Ru loadings in the membranes were likely to be smaller than those expected for complete monolayer coverage. In addition, there was likely to be significant variation in the Fe and Ru loading among the membranes due to difficulties in nucleating these materials on the aluminum oxide surfaces. The first series of experiments using coated membranes demonstrated that the technology needed further improvement. Specifically, observed catalytic FT activity was low. This low activity appeared to be due to: (1) low available surface area, (2) atomic deposition techniques that needed improvements, and (3) insufficient preconditioning of the catalyst surface prior to FT testing. Therefore, experimentation was expanded to the use of particulate silica supports having defined channels and reasonably high surface area. This later experimentation will be discussed in the next progress report. Subsequently, we plan to evaluate membranes after the ALD techniques are improved with a careful study to control and quantify the Fe and Ru loadings. The preconditioning of these surfaces will also be further developed. (A number of improvements have been made with particulate supports; they will be discussed in the subsequent report.) In support of the above, there was an opportunity to undertake a short study of cobalt/promoter/support interaction using the Advanced Photon Source (APS) of Argonne. Five catalysts and a reference cobalt oxide were characterized during a temperature programmed EXAFS/XANES experimental study with the combined effort of Argonne and the Center for Applied Energy Research (CAER) of the University of Kentucky. This project was completed, and it resulted in an extensive understanding of the preconditioning step of reducing Co-containing FT catalysts. A copy of the resulting manuscript has been submitted and accepted for publication. A similar project was undertaken with iron-containing FT catalysts; the data is currently being studied.

Cronauer, D. C. (Chemical Sciences and Engineering Division)

2011-04-15T23:59:59.000Z

71

Ion-exchanged pillared clays: A new class of catalysts for selective catalytic reduction of NO by hydrocarbons and by ammonia  

SciTech Connect (OSTI)

Selective catalytic reduction (SCR) of NO by NH{sub 3} is presently performed with vanadia-based catalysts for flue gas applications. Hydrocarbons would be the preferred reducing agents over NH{sub 3} because of the practical problems associated with the use of NH{sub 3} (i.e., handling and slippage through the reactor). SCR of NO by hydrocarbons can also find important applications for lean-burn (i.e., O{sub 2}-rich) gasoline and diesel engines where the noble-metal three-way catalysts are not effective in the presence of excess oxygen. Pillared interlayered clays (PILCs) have been studied extensively for a number of catalyzed reactions. We have found high activities of PILCs for SCR of NO by NH{sub 3} (26.28). Pillared clays have considerable Bronsted acidity (27, 28), and the protons can be exchanged with metal cations. The Bronsted acidity of TiO{sub 2}-PILC, in particular, remains high after heat treatment at temperatures as high as 400{degrees}C (27-29). In this note, we report first results on the activities of cation-exchanged pillared clays for SCR of NO by both hydrocarbon and NH{sub 3}. 37 refs., 3 figs.

NONE

1995-09-01T23:59:59.000Z

72

Integrated Removal of NOx with Carbon Monoxide as Reductant, and Capture of Mercury in a Low Temperature Selective Catalytic and Adsorptive Reactor  

SciTech Connect (OSTI)

Coal will likely continue to be a dominant component of power generation in the foreseeable future. This project addresses the issue of environmental compliance for two important pollutants: NO{sub x} and mercury. Integration of emission control units is in principle possible through a Low Temperature Selective Catalytic and Adsorptive Reactor (LTSCAR) in which NO{sub x} removal is achieved in a traditional SCR mode but at low temperature, and, uniquely, using carbon monoxide as a reductant. The capture of mercury is integrated into the same process unit. Such an arrangement would reduce mercury removal costs significantly, and provide improved control for the ultimate disposal of mercury. The work completed in this project demonstrates that the use of CO as a reductant in LTSCR is technically feasible using supported manganese oxide catalysts, that the simultaneous warm-gas capture of elemental and oxidized mercury is technically feasible using both nanostructured chelating adsorbents and ceria-titania-based materials, and that integrated removal of mercury and NO{sub x} is technically feasible using ceria-titania-based materials.

Neville Pinto; Panagiotis Smirniotis; Stephen Thiel

2010-08-31T23:59:59.000Z

73

Final Report of a CRADA Between Pacific Northwest National Laboratory and the General Motors Company (CRADA No. PNNL/271): “Degradation Mechanisms of Urea Selective Catalytic Reduction Technology”  

SciTech Connect (OSTI)

Diesel engines can offer substantially higher fuel efficiency, good driving performance characteristics, and reduced carbon dioxide (CO2) emission compared to stoichiometric gasoline engines. Despite the increasing public demand for higher fuel economy and reduced dependency on imported oil, however, meeting the stringent emission standards with affordable methods has been a major challenge for the wide application of these fuel-efficient engines in the US market. The selective catalytic reduction of NOx by urea (urea-SCR) is one of the most promising technologies for NOx emission control for diesel engine exhausts. To ensure successful NOx emission control in the urea-SCR technology, both a diesel oxidation catalyst (DOC) and a urea-SCR catalyst with high activity and durability are critical for the emission control system. Because the use of this technology for light-duty diesel vehicle applications is new, the relative lack of experience makes it especially challenging to satisfy the durability requirements. Of particular concern is being able to realistically simulate actual field aging of the catalyst systems under laboratory conditions, which is necessary both as a rapid assessment tool for verifying improved performance and certifiability of new catalyst formulations. In addition, it is imperative to develop a good understanding of deactivation mechanisms to help develop improved catalyst materials. In this CRADA program, General Motors Company and PNNL have investigated fresh, laboratory- and vehicle-aged DOC and SCR catalysts. The studies have led to a better understanding of various aging factors that impact the long-term performance of catalysts used in the urea-SCR technology, and have improved the correlation between laboratory and vehicle aging for reduced development time and cost. This Final Report briefly highlights many of the technical accomplishments and documents the productivity of the program in terms of peer-reviewed scientific publications (2 total), reports (3 total including this Final Report), and presentations (5 total).

Kim, Do Heui; Lee, Jong H.; Peden, Charles HF; Howden, Ken; Kim, Chang H.; Oh, Se H.; Schmieg, Steven J.; Wiebenga, Michelle H.

2011-12-13T23:59:59.000Z

74

CATALYTIC BIOMASS LIQUEFACTION  

E-Print Network [OSTI]

LBL-11 019 UC-61 CATALYTIC BIOMASS LIQUEFACTION Sabri Ergun,Catalytic Liquefaction of Biomass,n M, Seth, R. Djafar, G.of California. CATALYTIC BIOMASS LIQUEFACTION QUARTERLY

Ergun, Sabri

2013-01-01T23:59:59.000Z

75

Catalytic reactor  

DOE Patents [OSTI]

A catalytic reactor is provided with one or more reaction zones each formed of set(s) of reaction tubes containing a catalyst to promote chemical reaction within a feed stream. The reaction tubes are of helical configuration and are arranged in a substantially coaxial relationship to form a coil-like structure. Heat exchangers and steam generators can be formed by similar tube arrangements. In such manner, the reaction zone(s) and hence, the reactor is compact and the pressure drop through components is minimized. The resultant compact form has improved heat transfer characteristics and is far easier to thermally insulate than prior art compact reactor designs. Various chemical reactions are contemplated within such coil-like structures such that as steam methane reforming followed by water-gas shift. The coil-like structures can be housed within annular chambers of a cylindrical housing that also provide flow paths for various heat exchange fluids to heat and cool components.

Aaron, Timothy Mark (East Amherst, NY); Shah, Minish Mahendra (East Amherst, NY); Jibb, Richard John (Amherst, NY)

2009-03-10T23:59:59.000Z

76

Catalytic Coherence  

E-Print Network [OSTI]

Due to conservation of energy we cannot directly turn a quantum system with a definite energy into a superposition of different energies. However, if we have access to an additional resource in terms of a system with a high degree of coherence, as for standard models of laser light, we can overcome this limitation. The question is to what extent coherence gets degraded when utilized. Here it is shown that coherence can be turned into a catalyst, meaning that we can use it repeatedly without ever diminishing its power to enable coherent operations. This finding stands in contrast to the degradation of other quantum resources, and has direct consequences for quantum thermodynamics, as it shows that latent energy that may be locked into superpositions of energy eigenstates can be released catalytically.

Johan Aberg

2014-10-20T23:59:59.000Z

77

Catalytic reduction system for oxygen-rich exhaust  

DOE Patents [OSTI]

Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO{sub x} reduction in oxygen-rich vehicle engine exhausts. 8 figs.

Vogtlin, G.E.; Merritt, B.T.; Hsiao, M.C.; Wallman, P.H.; Penetrante, B.M.

1999-04-13T23:59:59.000Z

78

Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Engine Emissions Reduction (DEER) Conference Presentations and Posters 2005deermarshall.pdf More Documents & Publications Bifunctional Catalysts for the Selective Catalytic...

79

Innovative clean coal technology (ICCT): Demonstration of selective catalytic reduction (SCR) technology for the control of nitrogen oxide (NO{sub x}) emissions from high-sulfur coal-fired boilers. Quarterly report No. 3, January--March 1991  

SciTech Connect (OSTI)

The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from US, Japanese and European catalyst suppliers on a high-sulfur US coal-fired boiler. SCR is a post-combustion nitrogen oxide (NOx) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NOx to convert it to nitrogen and water vapor.

Not Available

1991-07-01T23:59:59.000Z

80

Innovative clean coal technology (ICCT): Demonstration of selective catalytic reduction (SCR) technology for the control of nitrogen oxide (NO sub x ) emissions from high-sulfur coal-fired boilers  

SciTech Connect (OSTI)

The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from US, Japanese and European catalyst suppliers on a high-sulfur US coal-fired boiler. SCR is a post-combustion nitrogen oxide (NOx) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NOx to convert it to nitrogen and water vapor.

Not Available

1991-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Innovative Clean Coal Technology (ICCT): Demonstration of Selective Catalytic Reduction (SCR) technology for the control of nitrogen oxide (NO{sub x}) emissions from high-sulfur coal-fired boilers. Quarterly report No. 6, October--December, 1991  

SciTech Connect (OSTI)

The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from US, Japanese and European catalyst suppliers on a high-sulfur US coal-fired boiler. SCR is a post-combustion nitrogen oxide (NOx) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NOx to convert it to nitrogen and water vapor.

Not Available

1992-02-01T23:59:59.000Z

82

Innovative Clean Coal Technology (ICCT): Demonstration of Selective Catalytic Reduction (SCR) technology for the control of nitrogen oxide (NO sub x ) emissions from high-sulfur coal-fired boilers  

SciTech Connect (OSTI)

The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from US, Japanese and European catalyst suppliers on a high-sulfur US coal-fired boiler. SCR is a post-combustion nitrogen oxide (NOx) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NOx to convert it to nitrogen and water vapor.

Not Available

1992-02-01T23:59:59.000Z

83

CATALYTIC LIQUEFACTION OF BIOMASS  

E-Print Network [OSTI]

liquid Fuels from Biomass: "Catalyst Screening and KineticUC-61 (l, RCO osn CDL or BIOMASS CATALYTIC LIQUEFACTION ManuCATALYTIC LIQUEFACTION OF BIOMASS Manu Seth, Roger Djafar,

Seth, Manu

2012-01-01T23:59:59.000Z

84

CATALYTIC BIOMASS LIQUEFACTION  

E-Print Network [OSTI]

Solvent Systems Catalystic Biomass Liquefaction Investigatereactor Product collection Biomass liquefaction process12-13, 1980 CATALYTIC BIOMASS LIQUEFACTION Sabri Ergun,

Ergun, Sabri

2013-01-01T23:59:59.000Z

85

Ability of Catalytic Converters to Reduce Air Pollution  

E-Print Network [OSTI]

NOx - 1 Ability of Catalytic Converters to Reduce Air Pollution MEASUREMENT OF SELECTED AIR POLLUTANTS IN CAR EXHAUST Last updated: June 17, 2014 #12;NOx - 2 Ability of Catalytic Converters to Reduce Air Pollution MEASUREMENT OF SELECTED AIR POLLUTANTS IN CAR EXHAUST INTRODUCTION Automobile engines

Nizkorodov, Sergey

86

Catalytic dense membranes of doped Bi4V2O11 (BIMEVOX) for selective partial oxidation: chemistry of defects vs. catalysis  

E-Print Network [OSTI]

), which determine the selectivity, either to mild oxidation products (acrolein, hexadiene, CO like methanol, acrolein and the like (acrylonitrile, acrylic acid), maleic anhydride, phthalic

Paris-Sud XI, Université de

87

Flame retardant finishing of cotton fleece.  

E-Print Network [OSTI]

??In this research, an inorganic phosphorus-containing flame retardant system was developed for cotton fleece. The aluminum hydroxyphosphate (AHP) formed in situ on cotton by the… (more)

Wu, Xialing

2008-01-01T23:59:59.000Z

88

Rich catalytic injection  

DOE Patents [OSTI]

A gas turbine engine includes a compressor, a rich catalytic injector, a combustor, and a turbine. The rich catalytic injector includes a rich catalytic device, a mixing zone, and an injection assembly. The injection assembly provides an interface between the mixing zone and the combustor. The injection assembly can inject diffusion fuel into the combustor, provides flame aerodynamic stabilization in the combustor, and may include an ignition device.

Veninger, Albert (Coventry, CT)

2008-12-30T23:59:59.000Z

89

Catalytic membranes for fuel cells  

DOE Patents [OSTI]

A fuel cell of the present invention comprises a cathode and an anode, one or both of the anode and the cathode including a catalyst comprising a bundle of longitudinally aligned graphitic carbon nanotubes including a catalytically active transition metal incorporated longitudinally and atomically distributed throughout the graphitic carbon walls of said nanotubes. The nanotubes also include nitrogen atoms and/or ions chemically bonded to the graphitic carbon and to the transition metal. Preferably, the transition metal comprises at least one metal selected from the group consisting of Fe, Co, Ni, Mn, and Cr.

Liu, Di-Jia (Naperville, IL); Yang, Junbing (Bolingbrook, IL); Wang, Xiaoping (Naperville, IL)

2011-04-19T23:59:59.000Z

90

CATALYTIC MICROWAVE PYROLYSIS OF BIOMASS FOR RENEWABLE PHENOLS AND FUELS .  

E-Print Network [OSTI]

??Bio-oil is an unstable intermediate and needs to be upgraded before its use. This study focused on improving the selectivity of bio-oilby catalytic pyrolysis of… (more)

[No author

2013-01-01T23:59:59.000Z

91

Innovative clean coal technology (ICCT): Demonstration of selective catalytic reduction (SCR) technology for the control of nitrogen oxide (NO{sub x}) emissions from high-sulfur coal-fired boilers. Fourth quarterly progress report  

SciTech Connect (OSTI)

The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from US, Japanese and European catalyst suppliers on a high-sulfur US coal-fired boiler. SCR is a post-combustion nitrogen oxide (NO{sub x}) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NO{sub x} to convert it to nitrogen and water vapor. Although SCR is widely practiced in Japan and Europe, there are numerous technical uncertainties include: (1) potential catalyst deactivation due to poisoning by trace metal species present in US coals that are not present in other fuels; (2) performance of the technology and effects on the balance-of-plant equipment in the presence of high amounts of SO{sub 2} and SO{sub 3}; and (3) performance of a wide variety of SCR catalyst compositions, geometries and methods of manufacture under typical high-sulfur coal-fired utility operating conditions. These uncertainties will be explored by constructing a series of small-scale SCR reactors and simultaneously exposing different SCR catalysts to flue gas derived from the combustion of high sulfur US coal.

NONE

1992-12-31T23:59:59.000Z

92

Catalytic bromine recovery from HBr waste  

SciTech Connect (OSTI)

Waste HBr is formed during the bromination of many organic molecules, such as flame retardants, pharmaceuticals, and agricultural chemicals. For over 50 years attempts to recover the bromine from waste HBr by catalytic oxidation have been unsuccessful due to low catalyst activity and stability. The discovery of a new high-activity catalysts with excellent long-term stability and life capable of high HBr conversion below 300{degrees}C has made catalytic oxidation of waste HBr commercially feasible. The oxidation of anhydrous HBr using oxygen is highly exothermic, giving an adiabatic temperature rise of 2000{degrees}C. Use of 48 wt% HBr in the oxidation reduces the adiabatic temperature rise to only 300{degrees}C. A multitubular heat exchanger type of reactor can then be used to manage the heat. A 5,000 kg/yr pilot plant was built to verify the performance of the catalyst, the suitability of the reactor materials of construction, and the multibular reactor concept. The pilot unit has a single full-scale reactor tube 4 m long and 2.54 cm in diameter with a hot oil jacket for heat management. Excellent catalyst stability was observed during a 600 h catalyst-life test. HBr conversion of 99% was maintained throughout the run, and over 360 kg of bromine was produced. The temperature at a localized hot spot near the reactor inlet was only 15-20{degrees}C above the reactor inlet temperature, indicating efficient heat management.

Schubert, P.F.; Beatty, R.D.; Mahajan, S. [Catalytica Inc., Mountain View, CA (United States)

1993-12-31T23:59:59.000Z

93

Steam reformer with catalytic combustor  

DOE Patents [OSTI]

A steam reformer is disclosed having an annular steam reforming catalyst bed formed by concentric cylinders and having a catalytic combustor located at the center of the innermost cylinder. Fuel is fed into the interior of the catalytic combustor and air is directed at the top of the combustor, creating a catalytic reaction which provides sufficient heat so as to maintain the catalytic reaction in the steam reforming catalyst bed. Alternatively, air is fed into the interior of the catalytic combustor and a fuel mixture is directed at the top. The catalytic combustor provides enhanced radiant and convective heat transfer to the reformer catalyst bed.

Voecks, Gerald E. (La Crescenta, CA)

1990-03-20T23:59:59.000Z

94

FTIR and kinetic studies of the mechanism of Fe{sup 3+}-exchanged TiO{sub 2}-pillared clay catalyst for selective catalytic reduction of NO with ammonia  

SciTech Connect (OSTI)

A series of FTIR spectroscopic and kinetic studies of the selective catalytic reduction (SCR) of nitric oxide by ammonia were conducted on Fe{sup 3+}-exchanged TiO{sub 2}-pillared clay (Fe-TiO{sub 2}-PILC) catalyst. It was found that No molecules were absorbed on the fresh Fe-TiO{sub 2}-PILC catalyst and then oxidized by O{sub 2} to adsorbed NO{sub 2} and nitrate species. These NO{sub x} adspecies could be reduced by NH{sub 3} at high temperatures. NH{sub 3} molecules could also be adsorbed on the Broensted acid and Lewis acid sites on the Fe-TiO{sub 2}-PILC catalyst to generate, respectively, NH{sup +}{sub 4} ions and coordinated NH{sub 3} species. These NH{sub 3} adspecies were active in reacting with NO, NO + O{sub 2} and NO{sub 2}, but the reaction rates of NH{sub 3} + NO + O{sub 2} and NH{sub 3} + NO{sub 2} were much higher than that of NNO + NH{sub 3}. However, under reaction conditions, the surface of Fe-TiO{sub 2}-PILC was mainly covered by NH{sup +}{sub 4} ions and coordinated NH{sub 3}, and no NO{sub x} adspecies were detected. This is in agreement with the zero-order for the SCR reaction with respect to NH{sub 3}. A possible reaction scheme for the SCR reaction on Fe-TiO{sub 2}-PILC was proposed. NO reduction initially involved the reaction between NO{sub 2} and pairs of NH{sub 3} adspecies to form an active intermediate, which finally reacted with gaseous or weakly adsorbed NO to produce N{sub 2} and H{sub 2}O.

Long, R.Q.; Yang, R.T.

2000-02-15T23:59:59.000Z

95

Demonstration of Selective Catalytic Reduction (SCR) technology for the control of nitrogen oxide (NO{sub x}) emissions from high-sulfur coal-fired boilers. Technical progress report, first and second quarters 1994  

SciTech Connect (OSTI)

The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from U.S., Japanese and European catalyst suppliers on a high-sulfur U.S. coal-fired boiler. SCR is a post-combustion nitrogen oxide (NO{sub x}) control technology that involve injecting ammonia into the flue gas generated from coal combustion in a boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NO{sub x} to form nitrogen and water vapor. Although SCR is widely practiced in Japan and Europe on gas-, oil-, and low-sulfur coal-fired boilers, there are several technical uncertainties associated with applying SCR to U.S. coals. These uncertainties include: (1) potential catalyst deactivation due to poisoning by trace metal species present in U.S. coals that are not present in other fuels; (2) performance of the technology and effects on the balance-of-plant equipment in the presence of high amounts of SO{sub 2} and SO{sub 3}; and (3) performance of a wide variety of SCR catalyst compositions, geometries and methods of manufacture under typical high-sulfur coal-fired utility operating conditions. These uncertainties are being explored by operating a series of small-scale SCR reactors and simultaneously exposing different SCR catalysts to flue gas derived from the combustion of high sulfur U.S. coal. The project is being conducted in the following three phases: permitting, environmental monitoring plan and preliminary engineering; detailed design engineering and construction; and operation, testing, disposition and final report. The project was in the operation and testing phase during this reporting period. Accomplishments for this period are described.

NONE

1995-11-01T23:59:59.000Z

96

Innovative Clean Coal Technology (ICCT): Demonstration of selective catalytic reduction technology for the control of nitrogen oxide emissions from high-sulfur coal-fired boilers. First and second quarterly technical progress reports, [January--June 1995]. Final report  

SciTech Connect (OSTI)

The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from US, Japanese and European catalyst suppliers on a high-sulfur US coal-fired boiler. SCR is a post-combustion nitrogen oxide (NO{sub x}) control technology that involves injecting ammonia (NH{sub 3}) into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor containing a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NO{sub x} to convert it to nitrogen and water vapor. Although SCR is widely practiced in Japan and Europe on gas-, oil-, and low-sulfur coal-fired boilers, there are several technical uncertainties associated with applying SCR to US coals. These uncertainties include: (1) potential catalyst deactivation due to poisoning by trace metal species present in US coals that are not present in other fuels. (2) performance of the technology and effects on the balance-of-plant equipment in the presence of high amounts of SO{sub 2} and SO{sub 3}. (3) performance of a wide variety of SCR catalyst compositions, geometries, and methods of manufacture under typical high-sulfur coal-fired utility operating conditions. These uncertainties are being explored by operating a series of small-scale SCR reactors and simultaneously exposing different SCR catalysts to flue gas derived from the combustion of high sulfur US coal. The demonstration is being performed at Gulf Power Company`s Plant Crist Unit No. 5 (75 MW nameplate capacity) near Pensacola, Florida. The project is funded by the US Department of Energy (DOE), Southern Company Services, Inc. (SCS on behalf of the entire Southern electric system), the Electric Power Research Institute (EPRI), and Ontario Hydro. SCS is the participant responsible for managing all aspects of this project.

NONE

1995-12-31T23:59:59.000Z

97

Innovative Clean Coal Technology (ICCT). Demonstration of Selective Catalytic Reduction (SCR) technology for the control of nitrogen oxide (NO{sub x}) emissions from high-sulfur coal-fired boilers: Volume 1. Final report  

SciTech Connect (OSTI)

The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from U.S., Japanese and European catalyst suppliers on a high-sulfur U.S. coal-fired boiler. SCR is a post-combustion nitrogen oxide (NO.) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NO. to convert it to nitrogen and water vapor. Although SCR is widely practiced in Japan and Europe on gas-, oil-, and low-sulfur coal- fired boilers, there are several technical uncertainties associated with applying SCR to U.S. coals. These uncertainties include: 1) potential catalyst deactivation due to poisoning by trace metal species present in U.S. coals that are not present in other fuels. 2) performance of the technology and effects on the balance-of- plant equipment in the presence of high amounts of SO{sub 2} and SO{sub 3}. 3) performance of a wide variety of SCR catalyst compositions, geometries and methods of manufacturer under typical high-sulfur coal-fired utility operating conditions. These uncertainties were explored by operating nine small-scale SCR reactors and simultaneously exposing different SCR catalysts to flue gas derived from the combustion of high sulfur U.S. coal. In addition, the test facility operating experience provided a basis for an economic study investigating the implementation of SCR technology.

NONE

1996-10-01T23:59:59.000Z

98

Demonstration of selective catalytic reduction (SCR) technology for the control of nitrogen oxide (NO{sub x}) emissions from high-sulfur coal-fired boilers. Draft final report  

SciTech Connect (OSTI)

The primary goal of this project was to demonstrate the use of Selective Catalytic Reduction (SCR) to reduce NO{sub x} emissions from pulverized-coal utility boilers using medium- to high-sulfur US coal. The prototype SCR facility, built in and around the ductwork of Plant Crist Unit 5, consisted of three large SCR reactor units (Reactors A, B, and C), each with a design capacity of 5,000 standard cubic feet per minute (scfm) of flue gas, and six smaller reactors (Reactors D through J), each with a design capacity of 400 scfm of flue gas. The three large reactors contained commercially available SCR catalysts as offered by SCR catalyst suppliers. These reactors were coupled with small-scale air preheaters to evaluate (1) the long-term effects of SCR reaction chemistry on air preheater deposit formation and (2) the impact of these deposits on the performance of air preheaters. The small reactors were used to test additional varieties of commercially available catalysts. The demonstration project was organized into three phases: (1) Permitting, Environmental Monitoring Plan (EMP) Preparation, and Preliminary Engineering; (2) Detail Design Engineering and Construction; and (3) Operation, Testing, Disposition, and Final Report Preparation. Section 2 discusses the planned and actual EMP monitoring for gaseous, aqueous, and solid streams over the course of the SCR demonstration project; Section 3 summarizes sampling and analytical methods and discusses exceptions from the methods specified in the EMP; Section 4 presents and discusses the gas stream monitoring results; Section 5 presents and discusses the aqueous stream monitoring results; Section 6 presents and discusses the solid stream monitoring results; Section 7 discusses EMP-related quality assurance/quality control activities performed during the demonstration project; Section 8 summarizes compliance monitoring reporting activities; and Section 9 presents conclusions based on the EMP monitoring results.

NONE

1996-06-14T23:59:59.000Z

99

Bifunctional Catalysts for the Selective Catalytic Reduction...  

Broader source: Energy.gov (indexed) [DOE]

in lean adsorption rich reduction cycles NO x Sorption (NO x Traps) Disadvantages Typical Usage Method Pioneering Science and Technology Office of Science U.S. Department of Energy...

100

Bifunctional Catalysts for the Selective Catalytic Reduction...  

Broader source: Energy.gov (indexed) [DOE]

zeolites * Alternate conditions - Diesel & natural gas engines * Systems approach - Argonne on-board reformer Pioneering Science and Technology Office of Science U.S. Department...

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Degradation Mechanisms of Urea Selective Catalytic Reduction...  

Broader source: Energy.gov (indexed) [DOE]

of rapid laboratory catalyst aging protocols is essential to reducing development cost and time. Goals and Objectives 4 * Develop an understanding of the deactivation...

102

Degradation Mechanisms of Urea Selective Catalytic Reduction...  

Broader source: Energy.gov (indexed) [DOE]

of rapid laboratory catalyst aging protocols is essential to reducing development cost. 4 Goals and Objectives * Develop an understanding of the deactivation mechanisms of...

103

Degradation Mechanisms of Urea Selective Catalytic Reduction...  

Broader source: Energy.gov (indexed) [DOE]

of rapid laboratory catalyst aging protocols is essential to reducing development cost. Goals and Objectives 4 * Develop an understanding of the deactivation mechanisms of...

104

Degradation Mechanisms of Urea Selective Catalytic Reduction...  

Broader source: Energy.gov (indexed) [DOE]

Chang H. Kim, Steven J. Schmieg, Michelle H. Wiegenga, and Se H. Oh General Motors Global R&D Center David B. Brown General Motors Powertrain ACE027 2 Project Overview...

105

A Photosynthetic Hydrogel for Catalytic Hydrogen Production ...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

A Photosynthetic Hydrogel for Catalytic Hydrogen Production Home > Research > ANSER Research Highlights > A Photosynthetic Hydrogel for Catalytic Hydrogen Production...

106

Center for Catalytic Science and Technology Recent Highlights from the Center for  

E-Print Network [OSTI]

for Catalytic Science and Technology CCST Research Areas Electrocatalysts and hydrogen processing for PEM fuel cells Selective oxidation and selective hydrogenation Biomass to fuels and chemicals phosphates prepared in ionic liquids A straightforward, cost-effective and scalable synthesis

Firestone, Jeremy

107

Catalytic hydrodesulfurization of bitumen  

SciTech Connect (OSTI)

Investigations of the catalytic hydrodesulfurization of Venezuela bitumen and its water emulsion (Orimulsion) were carried out. This material contained a large amount of sulfur and organometallics, such as vanadium and nickel compounds. A variety of nickel and molybdenum catalysts were prepared. These, as well as two commercial catalysts, were tested with Orimulsion and vacuum-dried, pentane-insoluble and soluble bitumen. Catalytic hydrotreatment removed up to 75% of sulfur from the bitumen. Hydrodesulfurization was found to be affected by reaction temperature, reaction time, catalyst, and feed material. Moisture-free bitumen and a pentane-soluble bitumen fraction were desulfurized more effectively than Orimulsion. Zeolite-based catalysts gave higher desulfurization than synthetic clay catalysts.

Sharma, R.K.; Olson, E.S. [Univ. of North Dakota, Grand Forks, ND (United States)

1995-12-31T23:59:59.000Z

108

Concentric catalytic combustor  

DOE Patents [OSTI]

A catalytic combustor (28) includes a tubular pressure boundary element (90) having a longitudinal flow axis (e.g., 56) separating a first portion (94) of a first fluid flow (e.g., 24) from a second portion (95) of the first fluid flow. The pressure boundary element includes a wall (96) having a plurality of separate longitudinally oriented flow paths (98) annularly disposed within the wall and conducting respective portions (100, 101) of a second fluid flow (e.g., 26) therethrough. A catalytic material (32) is disposed on a surface (e.g., 102, 103) of the pressure boundary element exposed to at least one of the first and second portions of the first fluid flow.

Bruck, Gerald J. (Oviedo, FL); Laster, Walter R. (Oviedo, FL)

2009-03-24T23:59:59.000Z

109

Catalytic reforming methods  

DOE Patents [OSTI]

A catalytic reforming method is disclosed herein. The method includes sequentially supplying a plurality of feedstocks of variable compositions to a reformer. The method further includes adding a respective predetermined co-reactant to each of the plurality of feedstocks to obtain a substantially constant output from the reformer for the plurality of feedstocks. The respective predetermined co-reactant is based on a C/H/O atomic composition for a respective one of the plurality of feedstocks and a predetermined C/H/O atomic composition for the substantially constant output.

Tadd, Andrew R; Schwank, Johannes

2013-05-14T23:59:59.000Z

110

Novel Catalytic Membrane Reactors  

SciTech Connect (OSTI)

There are many industrial catalytic organic reversible reactions with amines or alcohols that have water as one of the products. Many of these reactions are homogeneously catalyzed. In all cases removal of water facilitates the reaction and produces more of the desired chemical product. By shifting the reaction to right we produce more chemical product with little or no additional capital investment. Many of these reactions can also relate to bioprocesses. Given the large number of water-organic compound separations achievable and the ability of the Compact Membrane Systems, Inc. (CMS) perfluoro membranes to withstand these harsh operating conditions, this is an ideal demonstration system for the water-of-reaction removal using a membrane reactor. Enhanced reaction synthesis is consistent with the DOE objective to lower the energy intensity of U.S. industry 25% by 2017 in accord with the Energy Policy Act of 2005 and to improve the United States manufacturing competitiveness. The objective of this program is to develop the platform technology for enhancing homogeneous catalytic chemical syntheses.

Stuart Nemser, PhD

2010-10-01T23:59:59.000Z

111

Catalytic hydrodesulfurization of bitumen  

SciTech Connect (OSTI)

Investigations of the catalytic hydrodesulfurization of Venezuela bitumen and its water-emulsion (Orimulsion) were carried out. A variety of catalysts were prepared and some impregnated with molybdenum and sulfided. These and two commercial catalysts were tested with Orimulsion, vacuum-dried Orimulsion, and pentane-insoluble and soluble Orimulsion. Hydrotreatment of feed material was done in a 15-mL tube reactor using a variety of catalysts at 390{degrees}C under an initial 1000-psi hydrogen pressure with a reaction time of 1-3 hours. The hydrotreated products were analyzed by total sulfur analysis. Catalytic hydrotreatment removed up to 75% of sulfur from the bitumen. Nickel and/or molybdenum impregnation on various supports promoted sulfur removal from Orimulsion. Hydrodesulfurization was found to be affected by reaction temperature, reaction time, catalyst, and feed material. A moisture-free bitumen and a pentane-soluble bitumen fraction were desulfurized more effectively than Orimulsion. Zeolite-based catalysts gave higher desulfurization than synthetic clay catalysts or commercial AMOCAT and HDN catalysts.

Sharma, R.K.; Olson, E.S. [Univ. of North Dakota, Grand Forks, ND (United States)

1995-12-31T23:59:59.000Z

112

Nanotechnology finding its way into flame retardancy  

SciTech Connect (OSTI)

Nanotechnology is one of the key technologies of the 21{sup st} century. The exploitation of 'new' effects that arise from materials structured on the nano-scale has also been proposed successfully for flame retardancy of polymers since the end of the 90s. Of all of the approaches these include, at this time the use of nanocomposites offers the best potential for industrial application, also some other ideas are sketched, such as using electrospun nanofibers mats or layer-by-layer deposits as protection coatings, as well as sub-micrometer multilayer coatings as effective IR-mirrors. The general phenomena, inducing a flow limit in the pyrolysing melt and changing the fire residue, are identified in nanocomposites. Key experiments are performed such as quasi online investigation of the protection layer formation to understand what is going on in detail. The flame retardancy mechanisms are discussed and their impact on fire behaviour quantified. With the latter, the presentation pushes forward the state of the art. For instance, the heat shielding is experimentally quantified for a layered silicate epoxy resin nanocomposite proving that it is the only import mechanism controlling the reduction in peak heat release rate in the investigated system for different irradiations. The flame retardancy performance is assessed comprehensively illuminating not only the strengths but also the weak points of the concepts. Guidelines for materials development are deduced and discussed. Apart from inorganic fillers (layered silicate, boehmite, etc.) not only carbon nanoobjects such as multiwall carbon nanotubes, multilayer graphene and graphene are investigated, but also nanoparticles that are more reactive and harbor the potential for more beneficial interactions with the polymer matrix.

Schartel, Bernhard, E-mail: bernhard.schartel@bam.de [BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin (Germany)

2014-05-15T23:59:59.000Z

113

Synthesis, Characterization, and Catalytic Function of Novel...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Characterization, and Catalytic Function of Novel Highly Dispersed Tungsten Oxide Catalysts on Mesoporous Silica . Synthesis, Characterization, and Catalytic Function of Novel...

114

Preparation, Characterization, and Catalytic Properties of Tungsten...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Preparation, Characterization, and Catalytic Properties of Tungsten Trioxide Cyclic Trimers on FeO(111)Pt(111). Preparation, Characterization, and Catalytic Properties of Tungsten...

115

Catalytic fast pyrolysis of lignocellulosic biomass  

SciTech Connect (OSTI)

Increasing energy demand, especially in the transportation sector, and soaring CO2 emissions necessitate the exploitation of renewable sources of energy. Despite the large variety of new energy Q3 carriers, liquid hydrocarbon still appears to be the most attractive and feasible form of transportation fuel taking into account the energy density, stability and existing infrastructure. Biomass is an abundant, renewable source of energy; however, utilizing it in a cost-effective way is still a substantial challenge. Lignocellulose is composed of three major biopolymers, namely cellulose, hemicellulose and lignin. Fast pyrolysis of biomass is recognized as an efficient and feasible process to selectively convert lignocellulose into a liquid fuel—bio-oil. However bio-oil from fast pyrolysis contains a large amount of oxygen, distributed in hundreds of oxygenates. These oxygenates are the cause of many negative properties, such as low heating values, high corrosiveness, high viscosity, and instability; they also greatly Q4 limit the application of bio-oil particularly as transportation fuel. Hydrocarbons derived from biomass are most attractive because of their high energy density and compatibility with the existing infrastructure. Thus, converting lignocellulose into transportation fuels via catalytic fast pyrolysis has attracted much attention. Many studies related to catalytic fast pyrolysis of biomass have been published. The main challenge of this process is the development of active and stable catalysts that can deal with a large variety of decomposition intermediates from lignocellulose. This review starts with the current understanding of the chemistry in fast pyrolysis of lignocellulose and focuses on the development of catalysts in catalytic fast pyrolysis. Recent progress in the experimental studies on catalytic fast pyrolysis of biomass is also summarized with the emphasis on bio-oil yields and quality.

Liu, Changjun; Wang, Huamin; Karim, Ayman M.; Sun, Junming; Wang, Yong

2014-11-21T23:59:59.000Z

116

Studies on the Ecological Impact of Evaporation Retardation Monolayers  

E-Print Network [OSTI]

TR-6 1966 Studies on the Ecological Impact of Evaporation Retardation Monolayers B.G. Wixson Texas Water Resources Institute Texas A&M University ...

Wixson, B.G.

117

Reaction mechanisms for catalytic partial oxidation systems : application to ethylene epoxidation  

E-Print Network [OSTI]

With the rapid advances in kinetic modeling, building elementary surface mechanisms have become vital to understand the complex chemistry for catalytic partial oxidation systems. Given that there is selected experimental ...

Anantharaman, Bharthwaj

2005-01-01T23:59:59.000Z

118

The catalytic oxidation of propane  

E-Print Network [OSTI]

THE CATALYTIC OXIDATION OP PROPANE A Thesis By Charles Frederick Sandersont * * June 1949 Approval as to style and content recommended: Head of the Department of Chemical Engineering THE CATALYTICi OXIDATTON OF PROPANE A Thesis By Charles... Frederick ;Sandersonit * June 1949 THE CATALYTIC OXIDATION OP PROPANE A Thesis Submitted to the Faculty of the Agricultural and Mechanical College of Texas in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Major...

Sanderson, Charles Frederick

1949-01-01T23:59:59.000Z

119

INTEGRAL CATALYTIC COMBUSTION/FUEL REFORMING  

E-Print Network [OSTI]

INTEGRAL CATALYTIC COMBUSTION/FUEL REFORMING FOR GAS TURBINE Prepared For: California Energy REPORT (FAR) INTEGRAL CATALYTIC COMBUSTION/FUEL REFORMING FOR GAS TURBINE CYCLES EISG AWARDEE University://www.energy.ca.gov/research/index.html. #12;Page 1 Integral Catalytic Combustion/Fuel Reforming for Gas Turbine Cycles EISG Grant # 99

120

Catalytic two-stage coal hydrogenation and hydroconversion process  

DOE Patents [OSTI]

A process for two-stage catalytic hydrogenation and liquefaction of coal to produce increased yields of low-boiling hydrocarbon liquid and gas products. In the process, the particulate coal is slurried with a process-derived liquid solvent and fed at temperature below about 650.degree. F. into a first stage catalytic reaction zone operated at conditions which promote controlled rate liquefaction of the coal, while simultaneously hydrogenating the hydrocarbon recycle oils at conditions favoring hydrogenation reactions. The first stage reactor is maintained at 650.degree.-800.degree. F. temperature, 1000-4000 psig hydrogen partial pressure, and 10-60 lb coal/hr/ft.sup.3 reactor space velocity. The partially hydrogenated material from the first stage reaction zone is passed directly to the close-coupled second stage catalytic reaction zone maintained at a temperature at least about 25.degree. F. higher than for the first stage reactor and within a range of 750.degree.-875.degree. F. temperature for further hydrogenation and thermal hydroconversion reactions. By this process, the coal feed is successively catalytically hydrogenated and hydroconverted at selected conditions, which results in significantly increased yields of desirable low-boiling hydrocarbon liquid products and minimal production of undesirable residuum and unconverted coal and hydrocarbon gases, with use of less energy to obtain the low molecular weight products, while catalyst life is substantially increased.

MacArthur, James B. (Denville, NJ); McLean, Joseph B. (So. Somerville, NJ); Comolli, Alfred G. (Yardley, PA)

1989-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Final Report of a CRADA Between Pacific Northwest National Laboratory and the Ford Motor Company (CRADA No. PNNL/265): “Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic Reduction Materials, and Development of Zeolite-Based Hydrocarbon Adsorber Materials”  

SciTech Connect (OSTI)

Reducing NOx emissions and particulate matter (PM) are primary concerns for diesel vehicles required to meet current LEV II and future LEV III emission standards which require 90+% NOx conversion. Currently, urea SCR as the NOx reductant and a Catalyzed Diesel Particulate Filter (CDPF) are being used for emission control system components by Ford Motor Company for 2010 and beyond diesel vehicles. Because the use of this technology for vehicle applications is new, the relative lack of experience makes it especially challenging to satisfy durability requirements. Of particular concern is being able to realistically simulate actual field aging of the catalyst systems under laboratory conditions. This is necessary both as a rapid assessment tool for verifying improved performance and certifiability of new catalyst formulations, and to develop a good understanding of deactivation mechanisms that can be used to develop improved catalyst materials. In addition to NOx and PM, the hydrocarbon (HC) emission standards are expected to become much more stringent during the next few years. Meanwhile, the engine-out HC emissions are expected to increase and/or be more difficult to remove. Since HC can be removed only when the catalyst becomes warm enough for its oxidation, three-way catalyst (TWC) and diesel oxidation catalyst (DOC) formulations often contain proprietary zeolite materials to hold the HC produced during the cold start period until the catalyst reaches its operating temperature (e.g., >200°C). Unfortunately, much of trapped HC tends to be released before the catalyst reaches the operating temperature. Among materials effective for trapping HC during the catalyst warm-up period, siliceous zeolites are commonly used because of their high surface area and high stability under typical operating conditions. However, there has been little research on the physical properties of these materials related to the adsorption and release of various hydrocarbon species found in the engine exhaust. For these reasons, automakers and engine manufacturers have difficulty improving their catalytic converters for meeting the stringent HC emission standards. In this collaborative program, scientists and engineers in the Institute for Integrated Catalysis at Pacific Northwest National Laboratory and at Ford Motor Company have investigated laboratory- and engine-aged SCR catalysts, containing mainly base metal zeolites. These studies are leading to a better understanding of various aging factors that impact the long-term performance of SCR catalysts and improve the correlation between laboratory and engine aging, saving experimental time and cost. We have also studied materials effective for the temporary storage of HC species during the cold-start period. In particular, we have examined the adsorption and desorption of various HC species produced during the combustion with different fuels (e.g., gasoline, E85, diesel) over potential HC adsorber materials, and measured the kinetic parameters to update Ford’s HC adsorption model. Since this CRADA has now been completed, in this final report we will provide brief summaries of most of the work carried out on this CRADA over the last several years.

Gao, Feng; Kwak, Ja Hun; Lee, Jong H.; Tran, Diana N.; Peden, Charles HF; Howden, Ken; Cheng, Yisun; Lupescu, Jason; Cavattaio, Giovanni; Lambert, Christine; McCabe, Robert W.

2013-02-14T23:59:59.000Z

122

Synthesis of Z-(Pinacolato)allylboron and Z-(Pinacolato)alkenylboron Compounds through Stereoselective Catalytic Cross-Metathesis  

E-Print Network [OSTI]

The first examples of catalytic cross-metathesis (CM) reactions that furnish Z-(pinacolato)allylboron and Z-(pinacolato)alkenylboron compounds are disclosed. Products are generated with high Z selectivity by the use of a ...

Kiesewetter, Elizabeth T.

123

The Role of Carbon in Catalytically Stabilized Transition Metal Sulfides  

SciTech Connect (OSTI)

Since WWII considerable progress has been made in understanding the basis for the activity and the selectivity of molybdenum and tungsten based hydrotreating catalysts. Recently, the focus of investigation has turned to the structure of the catalytically stabilized active catalyst. The surface of the catalytically stabilized MoS2 has been shown to be carbided with the formula MoSxCy under hydrotreating conditions. In this paper we review the basis for this finding and present new data extending the concept to the promoted TMS (transition metal sulfides) systems CoMoC and NiMoC. Freshly sulfided CoMoS and NiMoS catalyst have a strong tendency to form the carbided surface phases from any available carbon source.

Kelty,S.; Berhault, G.; Chianelli, R.

2007-01-01T23:59:59.000Z

124

Superconducting Cuprates on Catalytic Substrates - Energy Innovation...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Transmission Electricity Transmission Find More Like This Return to Search Superconducting Cuprates on Catalytic Substrates Brookhaven National Laboratory Contact BNL About...

125

Carbohydrate Derived-Pseudo-Lignin Can Retard Cellulose Biological Conversion  

E-Print Network [OSTI]

ARTICLE Carbohydrate Derived-Pseudo-Lignin Can Retard Cellulose Biological Conversion Rajeev Kumar degradation products, collectively termed as chars and/or pseudo-lignin. In order to understand the factors derived pseudo-lignin on cellulose conversion at the moderate to low enzyme loadings necessary

California at Riverside, University of

126

Path integral formulation of retardation effects in nonlinear optics Vladimir Chernyaka) and Shaul Mukamel  

E-Print Network [OSTI]

Path integral formulation of retardation effects in nonlinear optics Vladimir Chernyaka) and Shaul;accepted4 October 1993) The signaturesof retardation in nonlinear optical susceptibilitiesare studiedby optical signalsare usually'calculatedby first calculating a nonlinear susceptibility definedby expanding

Mukamel, Shaul

127

American Association on Mental Retardation 231 VOLUME 109, NUMBER 3: 231236 MAY 2004 AMERICAN JOURNAL ON MENTAL RETARDATION  

E-Print Network [OSTI]

reported for several neurode- velopmental syndromes. In adults with Down syndrome, for example JOURNAL ON MENTAL RETARDATION The Relationship Between Age and IQ in Adults With Williams Syndrome Yvonne age and IQ was evaluated in a cross-sectional sample of 80 individuals with Williams syndrome (17

Bellugi, Ursula

128

American Association on Mental Retardation 149 VOLUME 108, NUMBER 3: 149160 MAY 2003 AMERICAN JOURNAL ON MENTAL RETARDATION  

E-Print Network [OSTI]

, despite the fact that the receptive language levels of females surpassed that of males. Down syndrome individuals with Down syndrome function in the mild to moderate range of mental retardation (Chapman & Hesketh are almost invariably associated with Down syndrome (Chapman & Hesketh, 2000). Although less well

Nguyen, Danh

129

Diagnostic test for prenatal identification of Down's syndrome and mental retardation and gene therapy therefor  

DOE Patents [OSTI]

A a diagnostic test useful for prenatal identification of Down syndrome and mental retardation. A method for gene therapy for correction and treatment of Down syndrome. DYRK gene involved in the ability to learn. A method for diagnosing Down's syndrome and mental retardation and an assay therefor. A pharmaceutical composition for treatment of Down's syndrome mental retardation.

Smith, Desmond J. (Oakland, CA); Rubin, Edward M. (Berkeley, CA)

2000-01-01T23:59:59.000Z

130

Utilization of char from biomass gasification in catalytic applications  

E-Print Network [OSTI]

Utilization of char from biomass gasification in catalytic applications Naomi Klinghoffer Submitted Utilization of char from biomass gasification in catalytic applications Naomi Klinghoffer Utilization takes place during catalytic decomposition. This thesis focuses on the utilization of char as a catalyst

131

System Study of Rich Catalytic/Lean burn (RCL) Catalytic Combustion for Natural Gas and Coal-Derived Syngas Combustion Turbines  

SciTech Connect (OSTI)

Rich Catalytic/Lean burn (RCL{reg_sign}) technology has been successfully developed to provide improvement in Dry Low Emission gas turbine technology for coal derived syngas and natural gas delivering near zero NOx emissions, improved efficiency, extending component lifetime and the ability to have fuel flexibility. The present report shows substantial net cost saving using RCL{reg_sign} technology as compared to other technologies both for new and retrofit applications, thus eliminating the need for Selective Catalytic Reduction (SCR) in combined or simple cycle for Integrated Gasification Combined Cycle (IGCC) and natural gas fired combustion turbines.

Shahrokh Etemad; Lance Smith; Kevin Burns

2004-12-01T23:59:59.000Z

132

Measurement of diesel solid nanoparticle emissions using a catalytic...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

diesel solid nanoparticle emissions using a catalytic stripper for comparison with Europe's PMP protocol Measurement of diesel solid nanoparticle emissions using a catalytic...

133

Nanoporous carbon catalytic membranes and method for making the same  

DOE Patents [OSTI]

Catalytic membranes comprising highly-dispersed, catalytically-active metals in nanoporous carbon membranes and a novel single-phase process to produce the membranes.

Foley, Henry C. (Hockessin, DE); Strano, Michael (Wilmington, DE); Acharya, Madhav (New Castle, DE); Raich, Brenda A. (Houston, TX)

2002-01-01T23:59:59.000Z

134

Passive Catalytic Approach to Low Temperature NOx Emission Abatement...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Catalytic Approach to Low Temperature NOx Emission Abatement Passive Catalytic Approach to Low Temperature NOx Emission Abatement Numerically evaluated and optimized proposed...

135

High Catalytic Rates for Hydrogen Production Using Nickel Electrocatal...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

High Catalytic Rates for Hydrogen Production Using Nickel Electrocatalysts with Seven-Membered Diphosphine Ligands Containing High Catalytic Rates for Hydrogen Production Using...

136

Fuel-Flexible, Low-Emissions Catalytic Combustor for Opportunity...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Flexible, Low-Emissions Catalytic Combustor for Opportunity Fuels Fuel-Flexible, Low-Emissions Catalytic Combustor for Opportunity Fuels This fact sheet provides an overview of the...

137

TCS 2014 Symposium on Thermal and Catalytic Sciences for Biofuels...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

TCS 2014 Symposium on Thermal and Catalytic Sciences for Biofuels and Biobased Products TCS 2014 Symposium on Thermal and Catalytic Sciences for Biofuels and Biobased Products...

138

Catalytic Hydrothermal Gasification of Biomass  

SciTech Connect (OSTI)

A recent development in biomass gasification is the use of a pressurized water processing environment in order that drying of the biomass can be avoided. This paper reviews the research undertaken developing this new option for biomass gasification. This review does not cover wet oxidation or near-atmospheric-pressure steam-gasification of biomass. Laboratory research on hydrothermal gasification of biomass focusing on the use of catalysts is reviewed here, and a companion review focuses on non-catalytic processing. Research includes liquid-phase, sub-critical processing as well as super-critical water processing. The use of heterogeneous catalysts in such a system allows effective operation at lower temperatures, and the issues around the use of catalysts are presented. This review attempts to show the potential of this new processing concept by comparing the various options under development and the results of the research.

Elliott, Douglas C.

2008-05-06T23:59:59.000Z

139

Catalytic converter with thermoelectric generator  

SciTech Connect (OSTI)

The unique design of an electrically heated catalyst (EHC) and the inclusion of an ECO valve in the exhaust of an internal combustion engine will meet the strict new emission requirements, especially at vehicle cold start, adopted by several states in this country as well as in Europe and Japan. The catalytic converter (CC) has been a most useful tool in pollution abatement for the automobile. But the emission requirements are becoming more stringent and, along with other improvements, the CC must be improved to meet these new standards. Coupled with the ECO valve, the EHC can meet these new emission limits. In an internal combustion engine vehicle (ICEV), approximately 80% of the energy consumed leaves the vehicle as waste heat: out the tail pipe, through the radiator, or convected/radiated off the engine. Included with the waste heat out the tail pipe are the products of combustion which must meet strict emission requirements. The design of a new CC is presented here. This is an automobile CC that has the capability of producing electrical power and reducing the quantity of emissions at vehicle cold start, the Thermoelectric Catalytic Power Generator. The CC utilizes the energy of the exothermic reactions that take place in the catalysis substrate to produce electrical energy with a thermoelectric generator. On vehicle cold start, the thermoelectric generator is used as a heat pump to heat the catalyst substrate to reduce the time to catalyst light-off. Thus an electrically heated catalyst (EHC) will be used to augment the abatement of tail pipe emissions. Included with the EHC in the exhaust stream of the automobile is the ECO valve. This valve restricts the flow of pollutants out the tail pipe of the vehicle for a specified amount of time until the EHC comes up to operating temperature. Then the ECO valve opens and allows the full exhaust, now treated by the EHC, to leave the vehicle.

Parise, R.J.

1998-07-01T23:59:59.000Z

140

The effect of pressure on tricalcium silicate hydration at different temperatures and in the presence of retarding additives  

SciTech Connect (OSTI)

The hydration of tricalcium silicate (C{sub 3}S) is accelerated by pressure. However, the extent to which temperature and/or cement additives modify this effect is largely unknown. Time-resolved synchrotron powder diffraction has been used to study cement hydration as a function of pressure at different temperatures in the absence of additives, and at selected temperatures in the presence of retarding agents. The magnitudes of the apparent activation volumes for C{sub 3}S hydration increased with the addition of the retarders sucrose, maltodextrin, aminotri(methylenephosphonic acid) and an AMPS copolymer. Pressure was found to retard the formation of Jaffeite relative to the degree of C{sub 3}S hydration in high temperature experiments. For one cement slurry studied without additives, the apparent activation volume for C{sub 3}S hydration remained close to {approx} -28 cm{sup 3} mol{sup -1} over the range 25 to 60 C. For another slurry, there were possible signs of a decrease in magnitude at the lowest temperature examined.

Jupe, Andrew C.; Wilkinson, Angus P.; Funkhouser, Gary P. (Halliburton); (GIT)

2012-07-25T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

New Developments in Titania-Based Catalysts for Selective Catalytic...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. deer10chapman.pdf More Documents & Publications The Utility of...

142

Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic  

Energy Savers [EERE]

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector General Office of Audit Services Audit Report Department of Energy EffortsReduction Materials |

143

Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat Pump Models | Department1 Prepared by:DTEMoab MillVehicle Project

144

Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat Pump Models | Department1 Prepared by:DTEMoab MillVehicle ProjectReduction

145

Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat Pump Models | Department1 Prepared by:DTEMoab MillVehicle

146

Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat Pump Models | Department1 Prepared by:DTEMoab MillVehicleReduction Materials, and

147

Degradation Mechanisms of Urea Selective Catalytic Reduction Technology |  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat Pump Models | Department1 Prepared by:DTEMoab3DepartmentalDepartment of Energy

148

Degradation Mechanisms of Urea Selective Catalytic Reduction Technology |  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat Pump Models | Department1 Prepared by:DTEMoab3DepartmentalDepartment of

149

Degradation Mechanisms of Urea Selective Catalytic Reduction Technology |  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat Pump Models | Department1 Prepared by:DTEMoab3DepartmentalDepartment ofDepartment

150

Degradation Mechanisms of Urea Selective Catalytic Reduction Technology |  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat Pump Models | Department1 Prepared by:DTEMoab3DepartmentalDepartment

151

Selective Catalytic Reduction and Exhaust Gas Recirculation Systems  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage » SearchEnergyDepartment of Energy Moniz: WhatM-1at the High

152

Bifunctional Catalysts for the Selective Catalytic Reduction of NO by  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up fromDepartmentTie Ltd: ScopeDepartment1, 2011 DRAFTof Energy Beyond10

153

Bifunctional Catalysts for the Selective Catalytic Reduction of NO by  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up fromDepartmentTie Ltd: ScopeDepartment1, 2011 DRAFTof Energy Beyond10Hydrocarbons

154

New Developments in Titania-Based Catalysts for Selective Catalytic  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion | Department ofT ib l L d F S i DOETowardExecutiveRate

155

Catalytic two-stage coal hydrogenation process using extinction recycle of heavy liquid fraction  

DOE Patents [OSTI]

A process for catalytic two-stage hydrogenation and liquefaction of coal with selective extinction recycle of all heavy liquid fractions boiling above a distillation cut point of about 600.degree.-750.degree. F. to produce increased yields of low-boiling hydrocarbon liquid and gas products. In the process, the particulate coal feed is slurried with a process-derived liquid solvent normally boiling above about 650.degree. F. and fed into a first stage catalytic reaction zone operated at conditions which promote controlled rate liquefaction of the coal, while simultaneously hydrogenating the hydrocarbon recycle oils. The first stage reactor is maintained at 710.degree.-800.degree. F. temperature, 1000-4000 psig hydrogen partial pressure, and 10-90 lb/hr per ft.sup.3 catalyst space velocity. Partially hydrogenated material withdrawn from the first stage reaction zone is passed directly to the second stage catalytic reaction zone maintained at 760.degree.-860.degree. F. temperature for further hydrogenation and hydroconversion reactions. A 600.degree.-750.degree. F..sup.+ fraction containing 0-20 W % unreacted coal and ash solids is recycled to the coal slurrying step. If desired, the cut point lower boiling fraction can be further catalytically hydrotreated. By this process, the coal feed is successively catalytically hydrogenated and hydroconverted at selected conditions, to provide significantly increased yields of desirable low-boiling hydrocarbon liquid products and minimal production of hydrocarbon gases, and no net production of undesirable heavy oils and residuum materials.

MacArthur, James B. (Denville, NJ); Comolli, Alfred G. (Yardley, PA); McLean, Joseph B. (Somerville, NJ)

1989-01-01T23:59:59.000Z

156

Catalytic two-stage coal hydrogenation process using extinction recycle of heavy liquid fraction  

DOE Patents [OSTI]

A process is described for catalytic two-stage hydrogenation and liquefaction of coal with selective extinction recycle of all heavy liquid fractions boiling above a distillation cut point of about 600--750 F to produce increased yields of low-boiling hydrocarbon liquid and gas products. In the process, the particulate coal feed is slurried with a process-derived liquid solvent normally boiling above about 650 F and fed into a first stage catalytic reaction zone operated at conditions which promote controlled rate liquefaction of the coal, while simultaneously hydrogenating the hydrocarbon recycle oils. The first stage reactor is maintained at 710--800 F temperature, 1,000--4,000 psig hydrogen partial pressure, and 10-90 lb/hr per ft[sup 3] catalyst space velocity. Partially hydrogenated material withdrawn from the first stage reaction zone is passed directly to the second stage catalytic reaction zone maintained at 760--860 F temperature for further hydrogenation and hydroconversion reactions. A 600--750 F[sup +] fraction containing 0--20 W % unreacted coal and ash solids is recycled to the coal slurrying step. If desired, the cut point lower boiling fraction can be further catalytically hydrotreated. By this process, the coal feed is successively catalytically hydrogenated and hydroconverted at selected conditions, to provide significantly increased yields of desirable low-boiling hydrocarbon liquid products and minimal production of hydrocarbon gases, and no net production of undesirable heavy oils and residuum materials. 2 figs.

MacArthur, J.B.; Comolli, A.G.; McLean, J.B.

1989-10-17T23:59:59.000Z

157

Catalytic Properties of Supported MoO3 Catalysts for Oxidative Dehydrogenation of Propane  

E-Print Network [OSTI]

Catalytic Properties of Supported MoO3 Catalysts for Oxidative Dehydrogenation of Propane Kaidong The effects of MoOx structure on propane oxidative dehydrogenation (ODH) rates and selectivity were examined with those obtained on MoOx/ZrO2. On MoOx/Al2O3 catalysts, propane turnover rate increased with increasing Mo

Iglesia, Enrique

158

Vacuum-insulated catalytic converter  

DOE Patents [OSTI]

A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

Benson, David K. (Golden, CO)

2001-01-01T23:59:59.000Z

159

Methods and apparatuses for preparing a surface to have catalytic activity  

DOE Patents [OSTI]

The invention provides methods and apparatuses that utilize mass spectrometry for preparation of a surface to have catalytic activity through molecular soft-landing of mass selected ions. Mass spectrometry is used to generate combinations of atoms in a particular geometrical arrangement, and ion soft-landing selects this molecular entity or combination of entities and gently deposits the entity or combination intact onto a surface.

Cooks, Robert G. (West Lafayette, IN); Peng, Wen-Ping (West Lafayette, IN); Ouyang, Zheng (West Lafayette, IN); Goodwin, Michael P. (West Lafayette, IN)

2011-03-22T23:59:59.000Z

160

Polybrominated diphenyl ether flame retardants in the antarctic environment  

E-Print Network [OSTI]

, the historical record of dioxins, PCBs and DDTs in the same cores showed a decreasing trend. At present, PBDEs are recognized as a worldwide pollution problem since they have reached remote areas such as the deep ocean, the Arctic and Antarctica (de Boer et al... that cheerful and warm Brazilian spirit. You are my Aggie family! viii NOMENCLATURE #1; critical value of a statistical test used to reject the null hypothesis ANOVA Analysis of Variance BDE Brominated Diphenyl Ether BFR Brominated Flame Retardant DC...

Yogui, Gilvan Takeshi

2009-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

E-Print Network 3.0 - ataxia mental retardation Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

mental retardation BRCA12 (Ashkenazi Jewish mutations only)** Paraganglioma... C Tay Sachs disease All 37 gene sequencing MELAS Borjesen-Forssman-Lehmann syndrome: ......

162

Catalytic membrane program novation: High temperature catalytic membrane reactors. Final report  

SciTech Connect (OSTI)

The original objective was to develop an energy-efficient hydrocarbon dehydrogenation process based on catalytic membrane reactors. Golden Technologies determined that the goals of this contract would be best served by novating the contract to an end user or other interested party which is better informed on the economic justification aspects of petrochemical refining processes to carry out the remaining work. In light of the Chevron results, the program objective was broadened to include development of inorganic membranes for applications in the chemical industry. The proposed membrane technologies shall offer the potential to improve chemical production processes via conversion increase and energy savings. The objective of this subcontract is to seek a party that would serve as a prime contractor to carry out the remaining tasks on the agreement and bring the agreement to a successful conclusion. Four tasks were defined to select the prime contractor. They were (1) prepare a request for proposal, (2) solicit companies as potential prime contractors as well as team members, (3) discuss modifications requested by the potential prime contractors, and (4) obtain, review and rank the proposals. The accomplishments on the tasks is described in detail in the following sections.

Kleiner, R.N. [Kleiner (Richard N.), Englewood, CO (United States)] [Kleiner (Richard N.), Englewood, CO (United States)

1998-08-28T23:59:59.000Z

163

Catalytic Combustor for Fuel-Flexible Turbine  

SciTech Connect (OSTI)

Under the sponsorship of the U.S. Department of Energy's National Energy Technology Laboratory, Siemens Westinghouse is conducting a three-year program to develop an ultra low NOx, fuel flexible catalytic combustor for gas turbine application in IGCC. The program is defined in three phases: Phase 1-Implementation Plan, Phase 2-Validation Testing and Phase 3-Field Testing. The Phase 1 program has been completed. Phase II was initiated in October 2004. In IGCC power plants, the gas turbine must be capable of operating on syngas as a primary fuel and an available back-up fuel such as natural gas. In this program the Rich Catalytic Lean (RCL{trademark}) technology is being developed as an ultra low NOx combustor. In this concept, ultra low NOx is achieved by stabilizing a lean premix combustion process by using a catalytic reactor to react part of the fuel, increasing the fuel/air mixture temperature. In Phase 1, the feasibility of the catalytic concept for syngas application has been evaluated and the key technology issues identified. In Phase II the catalytic concept will be demonstrated through subscale testing. Phase III will consist of full-scale combustor basket testing on natural gas and syngas.

W. R. Laster; E. Anoshkina; P. Szedlacsek

2006-03-31T23:59:59.000Z

164

Studies Relevent to Catalytic Activation Co & other small Molecules  

SciTech Connect (OSTI)

Detailed annual and triannual reports describing the progress accomplished during the tenure of this grant were filed with the Program Manager for Catalysis at the Office of Basic Energy Sciences. To avoid unnecessary duplication, the present report will provide a brief overview of the research areas that were sponsored by this grant and list the resulting publications and theses based on this DOE supported research. The scientific personnel participating in (and trained by) this grant's research are also listed. Research carried out under this DOE grant was largely concerned with the mechanisms of the homogeneous catalytic and photocatalytic activation of small molecules such as carbon monoxide, dihydrogen and various hydrocarbons. Much of the more recent effort has focused on the dynamics and mechanisms of reactions relevant to substrate carbonylations by homogeneous organometallic catalysts. A wide range of modern investigative techniques were employed, including quantitative fast reaction methodologies such as time-resolved optical (TRO) and time-resolved infrared (TRIR) spectroscopy and stopped flow kinetics. Although somewhat diverse, this research falls within the scope of the long-term objective of applying quantitative techniques to elucidate the dynamics and understand the principles of mechanisms relevant to the selective and efficient catalytic conversions of fundamental feedstocks to higher value materials.

Ford, Peter C

2005-02-22T23:59:59.000Z

165

Electro Catalytic Oxidation (ECO) Operation  

SciTech Connect (OSTI)

The power industry in the United States is faced with meeting many new regulations to reduce a number of air pollutants including sulfur dioxide, nitrogen oxides, fine particulate matter, and mercury. With over 1,000 power plants in the US, this is a daunting task. In some cases, traditional pollution control technologies such as wet scrubbers and SCRs are not feasible. Powerspan's Electro-Catalytic Oxidation, or ECO{reg_sign} process combines four pollution control devices into a single integrated system that can be installed after a power plant's particulate control device. Besides achieving major reductions in emissions of sulfur dioxide (SO{sub 2}), nitrogen oxides (NOx), fine particulate matter (PM2.5) and mercury (Hg), ECO produces a highly marketable fertilizer, which can help offset the operating costs of the process system. Powerspan has been operating a 50-MW ECO commercial demonstration unit (CDU) at FirstEnergy Corp.'s R.E. Burger Plant near Shadyside, Ohio, since February 2004. In addition to the CDU, a test loop has been constructed beside the CDU to demonstrate higher NOx removal rates and test various scrubber packing types and wet ESP configurations. Furthermore, Powerspan has developed the ECO{reg_sign}{sub 2} technology, a regenerative process that uses a proprietary solvent to capture CO{sub 2} from flue gas. The CO{sub 2} capture takes place after the capture of NOx, SO{sub 2}, mercury, and fine particulate matter. Once the CO{sub 2} is captured, the proprietary solution is regenerated to release CO{sub 2} in a form that is ready for geological storage or beneficial use. Pilot scale testing of ECO{sub 2} began in early 2009 at FirstEnergy's Burger Plant. The ECO{sub 2} pilot unit is designed to process a 1-MW flue gas stream and produce 20 tons of CO{sub 2} per day, achieving a 90% CO{sub 2} capture rate. The ECO{sub 2} pilot program provided the opportunity to confirm process design and cost estimates, and prepare for large scale capture and sequestration projects. The objectives of this project were to prove at a commercial scale that ECO is capable of extended operations over a range of conditions, that it meets the reliability requirements of a typical utility, and that the fertilizer co-product can be consistently generated, providing ECO with an economic advantage over conventional technologies currently available. Further objectives of the project were to show that the ECO system provides flue gas that meets the inlet standards necessary for ECO{sub 2} to operate, and that the outlet CO{sub 2} and other constituents produced by the ECO{sub 2} pilot can meet Kinder-Morgan pipeline standards for purposes of sequestration. All project objectives are consistent with DOE's Pollution Control Innovations for Power Plants program goals.

Morgan Jones

2011-03-31T23:59:59.000Z

166

Porous Core-Shell Nanostructures for Catalytic Applications  

E-Print Network [OSTI]

C.Y Mou. Catalytic nano-rattle of Au@ hollow silica: towardshollow nanostructures induced by the Kirkendall effect: The basic concept. NanoHollow mesoporous aluminosilica spheres with perpendicular pore channels as catalytic nanoreactors. ACS Nano,

Ewers, Trevor David

2012-01-01T23:59:59.000Z

167

Identifying some high risk populations for mental retardation  

E-Print Network [OSTI]

- ' $3 0 It- 0 cC 5- O 0 Cl I 0 0 IO X 0 I IG C! OJ O dl III lO 0 0 I/l Cl O m I 0 0 I? Since maternal age is a continuous variable and such a variable cannot be subjected to a chi square it was necessary to categor1ze this data...'s Family 2I K X ILI 0 Y ?I IZ IL O og I? ILI z w In ILI 0 I- ILI I- ~z O O LLJ O C) (f) 22 FIGURE 4 Relative Frequencies of the Distribution of Institutionalized IG) and Community Based (CG) Groups of Mentally Retarded Individuals...

Duesterhoft, Kenneth Wayne

1980-01-01T23:59:59.000Z

168

Transparent and Catalytic Carbon Nanotube Films  

E-Print Network [OSTI]

, a reaction that is important for the dye-sensitized solar cell, with a charge-transfer resistance as measured for the dye-sensitized solar cell. Other possible applications include batteries, fuel cells to be electrochemically active in several systems.1,8­15 For example, they are catalytic in the dye-sensitized solar cell

Hone, James

169

Performance characterization of a hydrogen catalytic heater.  

SciTech Connect (OSTI)

This report describes the performance of a high efficiency, compact heater that uses the catalytic oxidation of hydrogen to provide heat to the GM Hydrogen Storage Demonstration System. The heater was designed to transfer up to 30 kW of heat from the catalytic reaction to a circulating heat transfer fluid. The fluid then transfers the heat to one or more of the four hydrogen storage modules that make up the Demonstration System to drive off the chemically bound hydrogen. The heater consists of three main parts: (1) the reactor, (2) the gas heat recuperator, and (3) oil and gas flow distribution manifolds. The reactor and recuperator are integrated, compact, finned-plate heat exchangers to maximize heat transfer efficiency and minimize mass and volume. Detailed, three-dimensional, multi-physics computational models were used to design and optimize the system. At full power the heater was able to catalytically combust a 10% hydrogen/air mixture flowing at over 80 cubic feet per minute and transfer 30 kW of heat to a 30 gallon per minute flow of oil over a temperature range from 100 C to 220 C. The total efficiency of the catalytic heater, defined as the heat transferred to the oil divided by the inlet hydrogen chemical energy, was characterized and methods for improvement were investigated.

Johnson, Terry Alan; Kanouff, Michael P.

2010-04-01T23:59:59.000Z

170

Tantalum pillard montmorillonite: II. Acidic and catalytic properties  

SciTech Connect (OSTI)

The acidic and catalytic properties of a series of Ta-PILCs synthesized with a different initial tantalum content were characterized by adsorption of gaseous probe molecules (TPD of ammonia and FTIR spectra of absorbed pyridine) and by the test reaction of 1-butanol dehydration. A large increase of acidity was noted in Ta-PILCs compared to Na-montmorillonite or tantalum oxide. Cross-linking pillars and silica layers of the clay induce stronger Lewis and new Bronsted sites. The lack of basic sites formation is evidenced by the dehydration of 1-butanol to butene selectivity (100%). The incorporation of the tantalum oxide between the montmorillonite sheets produce, within Ta-PILC, acid centers of the same nature as observed for the silicon-tantalum mixed oxides. 32 refs., 4 figs., 5 tabs.

Guiu, G.; Grange, P. [Universite Catholique de Louvain, Louvain-la-Neuve (Belgium)] [Universite Catholique de Louvain, Louvain-la-Neuve (Belgium)

1997-06-01T23:59:59.000Z

171

Producing Clean Syngas via Catalytic Reforming for Fuels Production  

SciTech Connect (OSTI)

Thermochemical biomass conversion to fuels and chemicals can be achieved through gasification to syngas. The biomass derived raw syngas contains the building blocks of carbon monoxide and hydrogen as well as impurities such as tars, light hydrocarbons, and hydrogen sulfide. These impurities must be removed prior to fuel synthesis. We used catalytic reforming to convert tars and hydrocarbons to additional syngas, which increases biomass carbon utilization. In this work, nickel based, fluidizable tar reforming catalysts were synthesized and evaluated for tar and methane reforming performance with oak and model syngas in two types of pilot scale fluidized reactors (recirculating and recirculating regenerating). Because hydrogen sulfide (present in raw syngas and added to model syngas) reacts with the active nickel surface, regeneration with steam and hydrogen was required. Pre and post catalyst characterization showed changes specific to the syngas type used. Results of this work will be discussed in the context of selecting the best process for pilot scale demonstration.

Magrini, K. A.; Parent, Y.; Jablonski, W.; Yung, M.

2012-01-01T23:59:59.000Z

172

Catalytic Synthesis of Oxygenates: Mechanisms, Catalysts and Controlling Characteristics  

SciTech Connect (OSTI)

This research focused on catalytic synthesis of unsymmetrical ethers as a part of a larger program involving oxygenated products in general, including alcohols, ethers, esters, carboxylic acids and their derivatives that link together environmentally compliant fuels, monomers, and high-value chemicals. The catalysts studied here were solid acids possessing strong Br�������¸nsted acid functionalities. The design of these catalysts involved anchoring the acid groups onto inorganic oxides, e.g. surface-grafted acid groups on zirconia, and a new class of mesoporous solid acids, i.e. propylsulfonic acid-derivatized SBA-15. The former catalysts consisted of a high surface concentration of sulfate groups on stable zirconia catalysts. The latter catalyst consists of high surface area, large pore propylsulfonic acid-derivatized silicas, specifically SBA-15. In both cases, the catalyst design and synthesis yielded high concentrations of acid sites in close proximity to one another. These materials have been well-characterization in terms of physical and chemical properties, as well as in regard to surface and bulk characteristics. Both types of catalysts were shown to exhibit high catalytic performance with respect to both activity and selectivity for the bifunctional coupling of alcohols to form ethers, which proceeds via an efficient SN2 reaction mechanism on the proximal acid sites. This commonality of the dual-site SN2 reaction mechanism over acid catalysts provides for maximum reaction rates and control of selectivity by reaction conditions, i.e. pressure, temperature, and reactant concentrations. This research provides the scientific groundwork for synthesis of ethers for energy applications. The synthesized environmentally acceptable ethers, in part derived from natural gas via alcohol intermediates, exhibit high cetane properties, e.g. methylisobutylether with cetane No. of 53 and dimethylether with cetane No. of 55-60, or high octane properties, e.g. diisopropylether with blending octane No. of 105, and can replace aromatics in liquid fuels.

Kamil Klier; Richard G. Herman

2005-11-30T23:59:59.000Z

173

Graduate Program Selection Process  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun with Big Sky LearningGet AssistanceCatalytic Sites .GraduateSelection Process

174

A design approach for improving the performance of single-grid planar retarding potential analyzers  

SciTech Connect (OSTI)

Planar retarding potential analyzers (RPAs) have a long flight history and have been included on numerous spaceflight missions including Dynamics Explorer, the Defense Meteorological Satellite Program, and the Communications/Navigation Outage Forecast System. RPAs allow for simultaneous measurement of plasma composition, density, temperature, and the component of the velocity vector normal to the aperture plane. Internal conductive grids are used to approximate ideal potential planes within the instrument, but these grids introduce perturbations to the potential map inside the RPA and cause errors in the measurement of the parameters listed above. A numerical technique is presented herein for minimizing these grid errors for a specific mission by varying the depth and spacing of the grid wires. The example mission selected concentrates on plasma dynamics near the sunset terminator in the equatorial region. The international reference ionosphere model is used to discern the average conditions expected for this mission, and a numerical model of the grid-particle interaction is used to choose a grid design that will best fulfill the mission goals.

Davidson, R. L.; Earle, G. D. [William B. Hanson Center for Space Sciences, University of Texas at Dallas, 800 W. Campbell Rd. WT15, Richardson, Texas 75080 (United States)

2011-01-15T23:59:59.000Z

175

Method and apparatus for a catalytic firebox reactor  

DOE Patents [OSTI]

A catalytic firebox reactor employing an exothermic catalytic reaction channel and multiple cooling conduits for creating a partially reacted fuel/oxidant mixture. An oxidation catalyst is deposited on the walls forming the boundary between the multiple cooling conduits and the exothermic catalytic reaction channel, on the side of the walls facing the exothermic catalytic reaction channel. This configuration allows the oxidation catalyst to be backside cooled by any fluid passing through the cooling conduits. The heat of reaction is added to both the fluid in the exothermic catalytic reaction channel and the fluid passing through the cooling conduits. After discharge of the fluids from the exothermic catalytic reaction channel, the fluids mix to create a single combined flow. A further innovation in the reactor incorporates geometric changes in the exothermic catalytic reaction channel to provide streamwise variation of the velocity of the fluids in the reactor.

Smith, Lance L. (North Haven, CT); Etemad, Shahrokh (Trumbull, CT); Ulkarim, Hasan (Hamden, CT); Castaldi, Marco J. (Bridgeport, CT); Pfefferle, William C. (Madison, CT)

2001-01-01T23:59:59.000Z

176

Aligned carbon nanotube with electro-catalytic activity for oxygen reduction reaction  

DOE Patents [OSTI]

A catalyst for an electro-chemical oxygen reduction reaction (ORR) of a bundle of longitudinally aligned carbon nanotubes having a catalytically active transition metal incorporated longitudinally in said nanotubes. A method of making an electro-chemical catalyst for an oxygen reduction reaction (ORR) having a bundle of longitudinally aligned carbon nanotubes with a catalytically active transition metal incorporated throughout the nanotubes, where a substrate is in a first reaction zone, and a combination selected from one or more of a hydrocarbon and an organometallic compound containing an catalytically active transition metal and a nitrogen containing compound and an inert gas and a reducing gas is introduced into the first reaction zone which is maintained at a first reaction temperature for a time sufficient to vaporize material therein. The vaporized material is then introduced to a second reaction zone maintained at a second reaction temperature for a time sufficient to grow longitudinally aligned carbon nanotubes over the substrate with a catalytically active transition metal incorporated throughout the nanotubes.

Liu, Di-Jia (Naperville, IL); Yang, Junbing (Westmont, IL); Wang, Xiaoping (Naperville, IL)

2010-08-03T23:59:59.000Z

177

Method for producing flame retardant porous products and products produced thereby  

DOE Patents [OSTI]

A method for fire retarding porous products used for thermal energy storage and products produced thereby is provided. The method includes treating the surface of the phase change material-containing porous products with a urea fire-retarding agent. Upon exposure to a flame, the urea forms an adduct with the phase change material which will not sustain combustion (is self-extinguishing) in air. No halogens or metal oxides are contained in the fire retardant, so no potentially noxious halide smoke or fumes are emitted if the product is continuously exposed to a flame. 1 fig.

Salyer, I.O.

1998-08-04T23:59:59.000Z

178

Method for producing flame retardant porous products and products produced thereby  

DOE Patents [OSTI]

A method for fire retarding porous products used for thermal energy storage and products produced thereby is provided. The method includes treating the surface of the phase change material-containing porous products with a urea fire-retarding agent. Upon exposure to a flame, the urea forms an adduct with the phase change material which will not sustain combustion (is self-extinguishing) in air. No halogens or metal oxides are contained in the fire retardant, so no potentially noxious halide smoke or fumes are emitted if the product is continuously exposed to a flame.

Salyer, Ival O. (Dayton, OH)

1998-08-04T23:59:59.000Z

179

Method for Producing Flame Retardant Porous Products and Products Produced Thereby  

DOE Patents [OSTI]

A method for fire retarding porous products used for thermal energy storage and products produced thereby is provided. The method includes treating the surface of the phase change material-containing porous products with a urea fire-retarding agent. Upon exposure to a flame, the urea forms an adduct with the phase change material which will not sustain combustion (is self-extinguishing) in air. No halogens or metal oxides are contained in the fire retardant, so no potentially noxious halide smoke or fumes are emitted if the product is continuously exposed to a flame.

Salyer, Ival O. (Dayton, OH)

1998-08-04T23:59:59.000Z

180

Catalytic extraction processing of contaminated scrap metal  

SciTech Connect (OSTI)

Molten Metal Technology was awarded a contract to demonstrate the applicability of the Catalytic Extraction Process, a proprietary process that could be applied to US DOE`s inventory of low level mixed waste. This paper is a description of that technology, and included within this document are discussions of: (1) Program objectives, (2) Overall technology review, (3) Organic feed conversion to synthetic gas, (4) Metal, halogen, and transuranic recovery, (5) Demonstrations, (6) Design of the prototype facility, and (7) Results.

Griffin, T.P.; Johnston, J.E.; Payea, B.M.; Zeitoon, B.M.

1995-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Preface: Challenges for Catalytic Exhaust Aftertreatment  

SciTech Connect (OSTI)

This special issue of Catalysis Today continues the tradition established since the 18th NAM in Cancun, 2003, of publishing the highlights coming from these catalytic after-treatment technologies sessions, where this volume contains 18 papers based on oral and poster presentations of the 23rd NAM, 2013. The guest editors would like to thank all of the catalyst scientists and engineers who presented in the "Emission control" sessions, and especially the authors who contributed to this special issue of Catalysis Today.

Nova, Isabella; Epling, Bill; Peden, Charles HF

2014-03-31T23:59:59.000Z

182

Excellent activity and selectivity of Cu-SSZ-13 in the selective catalytic  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsing ZirconiaPolicy and Assistance100 tonusing ARMEvenFlames.Exposedin this

183

Impact of retarded spark timing on engine combustion, hydrocarbon emissions, and fast catalyst light-off  

E-Print Network [OSTI]

An experimental study was performed to determine the effects of substantial spark retard on engine combustion, hydrocarbon (HC) emissions, feed gas enthalpy, and catalyst light-off. Engine experiments were conducted at ...

Hallgren, Brian E. (Brian Eric), 1976-

2005-01-01T23:59:59.000Z

184

Synthesis of Highly Efficient Flame Retardant High-Density Polyethylene Nanocomposites with Inorgano-Layered Double  

E-Print Network [OSTI]

Synthesis of Highly Efficient Flame Retardant High-Density Polyethylene Nanocomposites, Harbin 150080, P. R. China ABSTRACT: High-density polyethylene (HDPE) polymer nanocomposites containing. INTRODUCTION High density polyethylene (HDPE) has good electrical proper- ties, high stiffness, and tensile

Guo, John Zhanhu

185

An In-depth Investigation of an Aluminum Chloride Retarded Mud Acid System on Sandstone Reservoirs  

E-Print Network [OSTI]

Sandstone acidizing using mud acid is a quick and complex process where dissolution and precipitation occur simultaneously. Retarded mud acids are less reactive with the rock reducing the reaction rate hence increased penetration into the formation...

Aneto, Nnenna

2012-07-16T23:59:59.000Z

186

Layer-by-Layer Nanocoatings with Flame Retardant and Oxygen Barrier Properties: Moving Toward Renewable Systems  

E-Print Network [OSTI]

) clay to create a renewable flame retardant nanocoating for polyurethane foam. This coating system completely stops the melting of a flexible polyurethane foam when exposed to direct flame from a butane torch, with just 10 bilayers (~ 30 nm thick...

Laufer, Galina 1985-

2012-10-23T23:59:59.000Z

187

Carbon Dioxide Conversion to Valuable Chemical Products over Composite Catalytic Systems  

SciTech Connect (OSTI)

Presented is an experimental study on catalytic conversion of carbon dioxide into methanol, ethanol and acetic acid. Catalysts having different catalytic functions were synthesized and combined in different ways to enhance selectivity to desired products. The combined catalyst system possessed the following functions: methanol synthesis, Fischer-Tropsch synthesis, water-gas-shift and hydrogenation. Results showed that the methods of integrating these catalytic functions played important role in achieving desired product selectivity. It was speculated that if methanol synthesis sites were located adjacent to the C-C chain growth sites, the formation rate of C2 oxygenates would be enhanced. The advantage of using high temperature methanol catalyst PdZnAl in the combined catalyst system was demonstrated. In the presence of PdZnAl catalyst, the combined catalyst system was stable at temperature of 380oC. It was observed that, at high temperature, kinetics favored oxygenate formation. Results implied that the process can be intensified by operating at high temperature using Pd-based methanol synthesis catalyst. Steam reforming of the byproduct organics was demonstrated as a means to provide supplemental hydrogen. Preliminary process design, simulation, and economic analysis of the proposed CO2 conversion process were carried out. Economic analysis indicates how ethanol production cost was affected by the price of CO2 and hydrogen.

Dagle, Robert A.; Hu, Jianli; Jones, Susanne B.; Wilcox, Wayne A.; Frye, John G.; White, J. F.; Jiang, Juyuan; Wang, Yong

2013-05-01T23:59:59.000Z

188

Synthesis and Characterization of Transition Metal Complexes Useful for the Catalytic Deconstruction of Lignin  

SciTech Connect (OSTI)

Lignin is an earth-abundant biopolymer that is grossly underutilized as a source of fuels and value-added chemicals. However, lignin is an intractable heteropolymer, which makes it difficult to deconstruct and upgrade in many chemically selective biomass conversion routes. The development of new catalytic routes to depolymerize this recalcitrant biopolymer is required to more effectively utilize lignin. To that end, our group aims to synthesize and characterize a collection of inorganic and organometallic catalysts to promote atom-economical catalytic lignin depolymerization. These catalysts have been screened against a continuum of model compounds and biomass-derived lignin for their usefulness in the deconstruction of these substrates. In addition, we have coupled our experimental efforts with quantum mechanical calculations to elucidate the mechanisms of catalysts to identify the mechanisms of lignin depolymerization. Detailed synthetic procedures, as well as spectroscopic and crystallographic characterization and DFT calculations will be presented.

Chmely, S. C.; Kim, S.; Beckham, G. T.

2012-01-01T23:59:59.000Z

189

Single Supported Atoms Participate in Catalytic Processes | ornl...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Functional Materials for Energy Single Supported Atoms Participate in Catalytic Processes December 04, 2014 Pathways for NO oxidation on single Pt atoms supported on the (010)...

190

The Effects of Trace Contaminants on Catalytic Processing of...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Processing of Biomass-Derived Feedstocks . Abstract: Trace components in biomass feedstocks are potential catalyst poisons when catalytically processing these materials to...

191

Printing 3D Catalytic Devices | The Ames Laboratory  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Printing 3D Catalytic Devices Ames Laboratory scientist Igor Slowing discusses using 3D printers to create new materials, including catalysts...

192

Piloted rich-catalytic lean-burn hybrid combustor  

DOE Patents [OSTI]

A catalytic combustor assembly which includes, an air source, a fuel delivery means, a catalytic reactor assembly, a mixing chamber, and a means for igniting a fuel/air mixture. The catalytic reactor assembly is in fluid communication with the air source and fuel delivery means and has a fuel/air plenum which is coated with a catalytic material. The fuel/air plenum has cooling air conduits passing therethrough which have an upstream end. The upstream end of the cooling conduits is in fluid communication with the air source but not the fuel delivery means.

Newburry, Donald Maurice (Orlando, FL)

2002-01-01T23:59:59.000Z

193

Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway...  

Energy Savers [EERE]

the catalytic conversion of solubilized carbohydrate streams to hydrocarbon biofuels, utilizing data from recent efforts within the National Advanced Biofuels Consortium...

194

Catalytic multi-stage liquefaction (CMSL)  

SciTech Connect (OSTI)

Under contract with the U.S. Department of Energy, Hydrocarbon Technologies, Inc. has conducted a series of eleven catalytic, multi-stage, liquefaction (CMSL) bench scale runs between February, 1991, and September, 1995. The purpose of these runs was to investigate novel approaches to liquefaction relating to feedstocks, hydrogen source, improved catalysts as well as processing variables, all of which are designed to lower the cost of producing coal-derived liquid products. This report summarizes the technical assessment of these runs, and in particular the evaluation of the economic impact of the results.

Comolli, A.G.; Ganguli, P.; Karolkiewicz, W.F.; Lee, T.L.K.; Pradhan, V.R.; Popper, G.A.; Smith, T.; Stalzer, R.

1996-11-01T23:59:59.000Z

195

Methods for preparation of catalytic materials  

SciTech Connect (OSTI)

To establish guidelines for the development of a scientific basis for catalyst preparation is perhaps a very ambitious goal. One would re required first to answer the following rhetorical questions: what are the properties which determine the performance of a catalytic material; how can these properties be introduced, developed, and/or improved during preparation? The answer to these questions involves a comprehensive discussion of the theories of catalysis, which is beyond the scope of this review. The authors will attempt, instead, to provide a rationale for each reader to answer these questions on the basis of his/her own interests. They start the discussion by describing the fundamental steps in producing bulk catalysts and/or catalyst supports. The fundamental processes involved are those derived from traditional three-dimensional chemistry. The topic areas will include single-component and multicomponent metal oxides. Unsupported metallic catalysts are formed by transformations involving physical or chemical processes, and the preparation methods for this class of materials will be discussed next. Attention will then turn to the preparation of supported catalytic materials. The main topics to be discussed will be those related to the interaction between the support and the active phase when they are put together to generate the catalyst. In this approach, the authors exploit the virtually unexplored field of surface, or two-dimensional, physical chemistry. The materials considered include dispersed metals and alloys and composite oxides. 366 refs.

Schwarz, J.A. [Syracuse Univ., NY (United States). Dept. of Chemical Engineering and Materials Science; Contescu, C.; Contescu, A. [Romanian Academy, Bucharest (Romania). Inst. of Physical Chemistry

1995-05-01T23:59:59.000Z

196

Catalytic reactor for low-Btu fuels  

DOE Patents [OSTI]

An improved catalytic reactor includes a housing having a plate positioned therein defining a first zone and a second zone, and a plurality of conduits fabricated from a heat conducting material and adapted for conducting a fluid therethrough. The conduits are positioned within the housing such that the conduit exterior surfaces and the housing interior surface within the second zone define a first flow path while the conduit interior surfaces define a second flow path through the second zone and not in fluid communication with the first flow path. The conduit exits define a second flow path exit, the conduit exits and the first flow path exit being proximately located and interspersed. The conduits define at least one expanded section that contacts adjacent conduits thereby spacing the conduits within the second zone and forming first flow path exit flow orifices having an aggregate exit area greater than a defined percent of the housing exit plane area. Lastly, at least a portion of the first flow path defines a catalytically active surface.

Smith, Lance (North Haven, CT); Etemad, Shahrokh (Trumbull, CT); Karim, Hasan (Simpsonville, SC); Pfefferle, William C. (Madison, CT)

2009-04-21T23:59:59.000Z

197

Selective, nickel-catalyzed carbon-carbon bond-forming reactions of alkynes  

E-Print Network [OSTI]

Catalytic addition reactions to alkynes are among the most useful and efficient methods for preparing diverse types of substituted olefins. Controlling both regioselectivity and (EIZ)- selectivity in such transformations ...

Miller, Karen M. (Karen Marie)

2005-01-01T23:59:59.000Z

198

Catalytic Membrane Reactor for Extraction of Hydrogen from Bioethanol Reforming  

E-Print Network [OSTI]

-gas-shift catalytic membrane reactor, and (2) a multi-layer design for bioethanol reforming. A two-dimensional model is developed to describe reaction and diffusion in the catalytic membrane coupled with plug-flow equations in the retentate and permeate volumes using...

Kuncharam, Bhanu Vardhan

2013-11-26T23:59:59.000Z

199

A microreactor array for spatially resolved measurement of catalytic activity for high-throughput catalysis science  

SciTech Connect (OSTI)

We describe a 100 channel microreactor array capable of spatially resolved measurement of catalytic activity across the surface of a flat substrate. When used in conjunction with a composition spread alloy film (CSAF, e.g. Pd{sub x}Cu{sub y}Au{sub 1-x-y}) across which component concentrations vary smoothly, such measurements permit high-throughput analysis of catalytic activity and selectivity as a function of catalyst composition. In the reported implementation, the system achieves spatial resolution of 1 mm{sup 2} over a 10×10 mm{sup 2} area. During operation, the reactant gases are delivered at constant flow rate to 100 points of differing composition on the CSAF surface by means of a 100-channel microfluidic device. After coming into contact with the CSAF catalyst surface, the product gas mixture from each of the 100 points is withdrawn separately through a set of 100 isolated channels for analysis using a mass spectrometer. We demonstrate the operation of the device on a Pd{sub x}Cu{sub y}Au{sub 1-x-y} CSAF catalyzing the H{sub 2}-D{sub 2} exchange reaction at 333 K. In essentially a single experiment, we measured the catalytic activity over a broad swathe of concentrations from the ternary composition space of the Pd{sub x}Cu{sub y}Au{sub 1-x-y} alloy.

Kondratyuk, Petro; Gumuslu, Gamze; Shukla, Shantanu; Miller, James B.; Morreale, Bryan D.; Gellman, Andrew J.

2013-04-01T23:59:59.000Z

200

Preparation and characterization of VOx/TiO2 catalytic coatings on stainless steel plates for structured catalytic reactors.  

E-Print Network [OSTI]

for structured catalytic reactors. Thierry Giornelli, Axel Löfberg* and Elisabeth Bordes-Richard Unité de.Lofberg@univ-lille1.fr Abstract The parameters to be controlled to coat metallic walls by VOx/TiO2 catalysts which) was chosen because of its large application in industrial catalytic reactors. TiO2 films on stainless steel

Boyer, Edmond

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Catalytic cracking of residual petroleum fractions  

SciTech Connect (OSTI)

This paper reports on Arabian Light crude oil vacuum bottoms fractionated into five high-boiling fractions by wiped film evaporation, and the fractions subjected to catalytic cracking in a fixed-fluidized bed using a commercial equilibrium cracking catalyst. Density, aromaticity, and heteroatom content generally increased with boiling point, as did metals content except for vanadium and iron which demonstrated possible bimodal distributions. The cracking response of these fractions showed increasing yields of dry gas and coke, with decreasing gasoline yields, as a function of increasing apparent boiling point as would normally be expected. Surprisingly, however, local maxima were observed for wet gas yield and total conversion, with local minima for cycle oil and slurry yields, in the region of the 1200-1263{degrees}F (650-680{degrees}C) middle fraction. All fractions showed significant response to cracking, with coke yields generally being the only negative factor observed.

Moore, H.F.; Mayo, S.L.; Goolsby, T.L. (Research and Development Dept., Ashland Petroleum Co., Ashland, KY (US))

1991-01-01T23:59:59.000Z

202

Contact structure for use in catalytic distillation  

DOE Patents [OSTI]

A method is described for conducting catalytic chemical reactions and fractionation of the reaction mixture comprising feeding reactants into a distillation column reactor, contracting said reactant in liquid phase with a fixed bed catalyst in the form of a contact catalyst structure consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column. 7 figs.

Jones, E.M. Jr.

1984-03-27T23:59:59.000Z

203

Contact structure for use in catalytic distillation  

DOE Patents [OSTI]

A method and apparatus are disclosed for conducting catalytic chemical reactions and fractionation of the reaction mixture, comprising and feeding reactants into a distillation column reactor contracting said reactant in a liquid phase with a fixed bed catalyst in the form of a contact catalyst structure, consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column. 7 figs.

Jones, E.M. Jr.

1985-08-20T23:59:59.000Z

204

Contact structure for use in catalytic distillation  

DOE Patents [OSTI]

A method for conducting catalytic chemical reactions and fractionation of the reaction mixture comprising feeding reactants into a distillation column reactor contracting said reactant in liquid phase with a fixed bed catalyst in the form of a contact catalyst structure consisting of closed porous containers containing the catatlyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column.

Jones, Jr., Edward M. (Friendswood, TX)

1984-01-01T23:59:59.000Z

205

Contact structure for use in catalytic distillation  

DOE Patents [OSTI]

A method and apparatus for conducting catalytic chemical reactions and fractionation of the reaction mixture, comprising and feeding reactants into a distillation column reactor contracting said reactant in a liquid phase with a fixed bed catalyst in the form of a contact catalyst structure, consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column.

Jones, Jr., Edward M. (Friendswood, TX)

1985-01-01T23:59:59.000Z

206

Fluid catalytic cracking of heavy petroleum fractions  

SciTech Connect (OSTI)

A process is claimed for fluid catalytic cracking of residuum and other heavy oils comprising of gas oil, petroleum residue, reduced and whole crudes and shale oil to produce gasoline and other liquid products which are separated in various streams in a fractionator and associated vapor recovery equipment. The heat from combustion of coke on the coked catalyst is removed by reacting sulfur-containing coke deposits with steam and oxygen in a separate stripper-gasifier to produce a low btu gas stream comprising of sulfur compounds, methane, carbon monoxide, hydrogen, and carbon dioxide at a temperature of from about 1100/sup 0/F. To about 2200/sup 0/F. The partially regenerated catalyst then undergoes complete carbon removal in a regeneration vessel. The regenerated catalyst is recycled for re-use in the cracking of heavy petroleum fractions. The liquid products are gasoline, distillates, heavy fuel oil, and light hydrocarbons.

McHenry, K.W.

1981-06-30T23:59:59.000Z

207

Catalytic cartridge SO/sub 3/ decomposer  

DOE Patents [OSTI]

A catalytic cartridge surrounding a heat pipe driven by a heat source is utilized as a SO/sub 3/ decomposer for thermochemical hydrogen production. The cartridge has two embodiments, a cross-flow cartridge and an axial flow cartridge. In the cross-flow cartridge, SO/sub 3/ gas is flowed through a chamber and incident normally to a catalyst coated tube extending through the chamber, the catalyst coated tube surrounding the heat pipe. In the axial-flow cartridge, SO/sub 3/ gas is flowed through the annular space between concentric inner and outer cylindrical walls, the inner cylindrical wall being coated by a catalyst and surrounding the heat pipe. The modular cartridge decomposer provides high thermal efficiency, high conversion efficiency, and increased safety. A fusion reactor may be used as the heat source.

Galloway, T.R.

1980-11-18T23:59:59.000Z

208

Catalytic carbon membranes for hydrogen production  

SciTech Connect (OSTI)

Commercial carbon composite microfiltration membranes may be modified for gas separation applications by providing a gas separation layer with pores in the 1- to 10-nm range. Several organic polymeric precursors and techniques for depositing a suitable layer were investigated in this project. The in situ polymerization technique was found to be the most promising, and pure component permeation tests with membrane samples prepared with this technique indicated Knudsen diffusion behavior. The gas separation factors obtained by mixed-gas permeation tests were found to depend strongly on gas temperature and pressure indicating significant viscous flow at high-pressure conditions. The modified membranes were used to carry out simultaneous water gas shift reaction and product hydrogen separation. These tests indicated increasing CO conversions with increasing hydrogen separation. A simple process model was developed to simulate a catalytic membrane reactor. A number of simulations were carried out to identify operating conditions leading to product hydrogen concentrations over 90 percent. (VC)

Damle, A.S.; Gangwal, S.K.

1992-01-01T23:59:59.000Z

209

Solid state proton and electron mediating membrane and use in catalytic membrane reactors  

DOE Patents [OSTI]

This invention provides catalytic proton and electron mediating membranes useful in catalytic reactors. The membranes have an oxidation and a reduction surface and comprise a single-phase mixed metal oxide material of the formula: AB{sub 1{minus}x}B{prime}{sub x}O{sub 3{minus}y} wherein A is selected from Ca, Sr or Ba ions; B is selected from Ce, Tb, Pr, or Th ions; B{prime} is selected from Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Al, Ga, or In ions, or combinations thereof; and x is greater than or equal to 0.02 and less than or equal to 0.5. The membranes can further comprise a catalyst on either the oxidation or reduction surface, or both. Membranes include those which are fabricated by combining powders of metal oxides or metal carbonates of metal A ion, metal B ion and metal B{prime} ion such that the stoichiometric ratio A:B:B{prime} is 1:1{minus}x:x where 0.2{<=}{times}0.5, repeatedly calcining and milling the combined powders until a single-phase material is obtained and pressing and sintering the single phase material to obtain a membrane. 6 figs.

White, J.H.; Schwartz, M.; Sammells, A.F.

1998-10-13T23:59:59.000Z

210

The Human Genome Project and Mental Retardation: An Educational Program. Final Progress Report  

SciTech Connect (OSTI)

The Arc, a national organization on mental retardation, conducted an educational program for members, many of whom have a family member with a genetic condition causing mental retardation. The project informed members about the Human Genome scientific efforts, conducted training regarding ethical, legal and social implications and involved members in issue discussions. Short reports and fact sheets on genetic and ELSI topics were disseminated to 2,200 of the Arc's leaders across the country and to other interested individuals. Materials produced by the project can e found on the Arc's web site, TheArc.org.

Davis, Sharon

1999-05-03T23:59:59.000Z

211

Learned helplessness in mentally retarded and learning disabled versus normal subjects: an attributional approach  

E-Print Network [OSTI]

this project, he/she is free to do so. Upon completion of the project, a copy of the results will be mailed to you. 31 APPENDIX A (CONT. ) We feel that this study is important because it will help us to better understand motivation in children. We would... students and eighty normal subjects partic1pated 1n the study. Normal children were found to be signficantly more persistent than nonretarded children. Older retarded ch11dren showed signf1cantly more helplessness than e1ther of the other two retarded...

Davis, Veronica Ladell

1981-01-01T23:59:59.000Z

212

Challenges in Catalytic Manufacture of Renewable Pyrrolidinones from Fermentation Derived Succinate  

SciTech Connect (OSTI)

Fermentation derived succinic acid ammonium salt is an ideal precursor for manufacture of renewable N-methyl pyrrolidinone (NMP) or 2-pyrrolidinone (2P) via heterogeneous catalysis. However, there are many challenges to making this a practical reality. Chief among the challenges is avoiding catalyst poisoning by fermentation by- and co-products. Battelle / Pacific Northwest National Laboratory (PNNL) have developed an economically effective technology strategy for this purpose. The technology is a combination of purely thermal processing, followed by simple catalytic hydrogenation that together avoids catalyst poisoning from fermentation impurities and provides high selectivity and yields of NMP or 2P.

White, James F.; Holladay, Johnathan E.; Zacher, Alan H.; Frye, John G.; Werpy, Todd A.

2014-09-05T23:59:59.000Z

213

Sequential tasks performed by catalytic pumps for colloidal crystallization  

E-Print Network [OSTI]

Gold-platinum catalytic pumps immersed in a chemical fuel are used to manipulate silica colloids. The manipulation relies on the electric field and the fluid flow generated by the pump. Catalytic pumps perform various tasks, such as the repulsion of colloids, the attraction of colloids, and the guided crystallization of colloids. We demonstrate that catalytic pumps can execute these tasks sequentially over time. Switching from one task to the next is related to the local change of the proton concentration, which modifies the colloid zeta potential and consequently the electric force acting on the colloids.

Ali Afshar Farniya; Maria J. Esplandiu; Adrian Bachtold

2014-10-20T23:59:59.000Z

214

Study of fire retardant behavior of carbon nanotube membranes and carbon nanofiber paper in carbon fiber  

E-Print Network [OSTI]

were incorporated onto the surface of epoxy carbon fiber composites, as proposed fire shieldsStudy of fire retardant behavior of carbon nanotube membranes and carbon nanofiber paper in carbon fiber reinforced epoxy composites Qiang Wu, Wei Zhu, Chuck Zhang *, Zhiyong Liang, Ben Wang Department

Das, Suman

215

Selection Process  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Selection Process Selection Process Fellowships will be awarded based on academic excellence, relevance of candidate's research to the laboratory mission in fundamental nuclear...

216

atp catalytic domain: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 328 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

217

acidic multimetallic catalytic: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 106 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

218

automobile catalytic converters: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Odei 2006-01-01 408 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

219

atp catalytic cycle: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 275 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

220

advanced catalytic hydrogenation: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 188 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

apparent catalytic site: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 257 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

222

advanced catalytic materials: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 225 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

223

acrylamide catalytically inhibits: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 78 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

224

assisted catalytic oxidation: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 251 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

225

active catalytic sites: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 337 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

226

atpase catalytic domain: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 266 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

227

advanced catalytic materials 1996: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 467 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

228

archaeal primase catalytic: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 92 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

229

advanced catalytic science: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 488 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

230

Catalyst Cartography: 3D Super-Resolution Mapping of Catalytic...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Catalyst Cartography: 3D Super-Resolution Mapping of Catalytic Activity Thanks to a groundbreaking new method, scientists have created the first 3D super-resolution maps of...

231

Hydrogen permeable protective coating for a catalytic surface  

DOE Patents [OSTI]

A protective coating for a surface comprising a layer permeable to hydrogen, said coating being deposited on a catalyst layer; wherein the catalytic activity of the catalyst layer is preserved.

Liu, Ping (Irvine, CA); Tracy, C. Edwin (Golen, CO); Pitts, J. Roland (Lakewood, CO); Lee, Se-Hee (Lakewood, CO)

2007-06-19T23:59:59.000Z

232

In situ XAS Characterization of Catalytic Nano-Materials with...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

XAS Characterization of Catalytic Nano-Materials with Applications to Fuel Cells and Batteries Friday, July 12, 2013 - 11:00am SLAC, Conference Room 137-322 Presented by Qingying...

233

Catalytic H2O2 decomposition on palladium surfaces  

E-Print Network [OSTI]

The catalytic decomposition of H?O? at smooth single-crystal and polycrystalline palladium surfaces that had been subjected to various surface modifications has been studied. Monolayer and submonolayer coverages of I, Br and Cl adsorbates were used...

Salinas, S. Adriana

1998-01-01T23:59:59.000Z

234

Catalytic pyrolysis using UZM-39 aluminosilicate zeolite  

SciTech Connect (OSTI)

A new family of coherently grown composites of TUN and IMF zeotypes has been synthesized and shown to be effective catalysts for catalytic pyrolysis of biomass. These zeolites are represented by the empirical formula. Na.sub.nM.sub.m.sup.n+R.sub.rQ.sub.qAl.sub.1-xE.sub.xSi.sub.yO.s- ub.z where M represents zinc or a metal or metals from Group 1, Group 2, Group 3 or the lanthanide series of the periodic table, R is an A,.OMEGA.-dihalosubstituted paraffin such as 1,4-dibromobutane, Q is a neutral amine containing 5 or fewer carbon atoms such as 1-methylpyrrolidine and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-39 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hydrocarbons into hydrocarbons and removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

Nicholas, Christopher P; Boldingh, Edwin P

2014-10-07T23:59:59.000Z

235

Catalytic pyrolysis using UZM-39 aluminosilicate zeolite  

DOE Patents [OSTI]

A new family of coherently grown composites of TUN and IMF zeotypes has been synthesized and show to be effective catalysts for catalytic pyrolysis of biomass. These zeolites are represented by the empirical formula. Na.sub.nM.sub.m.sup.n+R.sub.rQ.sub.qAl.sub1-xE.sub.xSi.sub.yO.s- ub.z where M represents zinc or a metal or metals from Group 1, Group 2, Group 3 or the lanthanide series of the periodic table, R is an A,.OMEGA.-dihalosubstituted paraffin such as 1,4-dibromobutane, Q is a neutral amine containing 5 or fewer carbon atoms such as 1-methylpyrrolidine and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-39 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hyrdocarbons into hydrocarbons removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

Nicholas, Christpher P; Boldingh, Edwin P

2013-12-17T23:59:59.000Z

236

Catalytic Reactor For Oxidizing Mercury Vapor  

DOE Patents [OSTI]

A catalytic reactor (10) for oxidizing elemental mercury contained in flue gas is provided. The catalyst reactor (10) comprises within a flue gas conduit a perforated corona discharge plate (30a, b) having a plurality of through openings (33) and a plurality of projecting corona discharge electrodes (31); a perforated electrode plate (40a, b, c) having a plurality of through openings (43) axially aligned with the through openings (33) of the perforated corona discharge plate (30a, b) displaced from and opposing the tips of the corona discharge electrodes (31); and a catalyst member (60a, b, c, d) overlaying that face of the perforated electrode plate (40a, b, c) opposing the tips of the corona discharge electrodes (31). A uniformly distributed corona discharge plasma (1000) is intermittently generated between the plurality of corona discharge electrode tips (31) and the catalyst member (60a, b, c, d) when a stream of flue gas is passed through the conduit. During those periods when corona discharge (1000) is not being generated, the catalyst molecules of the catalyst member (60a, b, c, d) adsorb mercury vapor contained in the passing flue gas. During those periods when corona discharge (1000) is being generated, ions and active radicals contained in the generated corona discharge plasma (1000) desorb the mercury from the catalyst molecules of the catalyst member (60a, b, c, d), oxidizing the mercury in virtually simultaneous manner. The desorption process regenerates and activates the catalyst member molecules.

Helfritch, Dennis J. (Baltimore, MD)

1998-07-28T23:59:59.000Z

237

Microchannel Reactor System for Catalytic Hydrogenation  

SciTech Connect (OSTI)

We successfully demonstrated a novel process intensification concept enabled by the development of microchannel reactors, for energy efficient catalytic hydrogenation reactions at moderate temperature, and pressure, and low solvent levels. We designed, fabricated, evaluated, and optimized a laboratory-scale microchannel reactor system for hydrogenation of onitroanisole and a proprietary BMS molecule. In the second phase of the program, as a prelude to full-scale commercialization, we designed and developed a fully-automated skid-mounted multichannel microreactor pilot plant system for multiphase reactions. The system is capable of processing 1 – 10 kg/h of liquid substrate, and an industrially relevant immiscible liquid-liquid was successfully demonstrated on the system. Our microreactor-based pilot plant is one-of-akind. We anticipate that this process intensification concept, if successfully demonstrated, will provide a paradigm-changing basis for replacing existing energy inefficient, cost ineffective, environmentally detrimental slurry semi-batch reactor-based manufacturing practiced in the pharmaceutical and fine chemicals industries.

Adeniyi Lawal; Woo Lee; Ron Besser; Donald Kientzler; Luke Achenie

2010-12-22T23:59:59.000Z

238

Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway  

SciTech Connect (OSTI)

This technology pathway case investigates the catalytic conversion of solubilized carbohydrate streams to hydrocarbon biofuels, utilizing data from recent efforts within the National Advanced Biofuels Consortium (NABC) in collaboration with Virent, Inc. Technical barriers and key research needs that should be pursued for the catalytic conversion of sugars pathway to be competitive with petroleum-derived gasoline-, diesel-, and jet-range hydrocarbon blendstocks have been identified.

Biddy, M.; Jones, S.

2013-03-01T23:59:59.000Z

239

Effects of dispersion and support on adsorption, catalytic and electronic properties of cobalt/alumina CO hydrogenation catalysts: (Technical progress report)  

SciTech Connect (OSTI)

The continued investigation of dispersion and metal-support interactions and their effects upon the adsorption, activity/selectivity, and electronic properties of the metal in cobalt/alumina (and to a lesser extent on iron/alumina) catalysts is proposed. The objectives of this research are to determine the effects of surface structure and metal dispersion on the adsorption and catalytic properties of cobalt, and determine the effects of metal-support interactions, i.e., effects of decorating support species on metal crystallites and of direct electronic interactions between metal clusters and the support, on the adsoprtion, catalytic and electronic properties of cobalt supported on alumina.

Bartholomew, C.H. Jr.

1986-12-22T23:59:59.000Z

240

Atomically precise (catalytic) particles synthesized by a novel cluster deposition instrument  

SciTech Connect (OSTI)

We report a new high vacuum instrument which is dedicated to the preparation of well-defined clusters supported on model and technologically relevant supports for catalytic and materials investigations. The instrument is based on deposition of size selected metallic cluster ions that are produced by a high flux magnetron cluster source. The throughput of the apparatus is maximized by collecting and focusing ions utilizing a conical octupole ion guide and a linear ion guide. The size selection is achieved by a quadrupole mass filter. The new design of the sample holder provides for the preparation of multiple samples on supports of various sizes and shapes in one session. After cluster deposition onto the support of interest, samples will be taken out of the chamber for a variety of testing and characterization.

Yin, C.; Tyo, E. [Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States)] [Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States); Kuchta, K. [Extrel CMS, LLC, 575 Epsilon Dr. Suite 2, Pittsburgh, Pennsylvania 15238-2838 (United States)] [Extrel CMS, LLC, 575 Epsilon Dr. Suite 2, Pittsburgh, Pennsylvania 15238-2838 (United States); Issendorff, B. von [Physikalisches Institut, Universität Freiburg, Stefan-Meier Str. 21, D-79104 Freiburg (Germany)] [Physikalisches Institut, Universität Freiburg, Stefan-Meier Str. 21, D-79104 Freiburg (Germany); Vajda, S., E-mail: vajda@anl.gov [Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States); Nanoscience and Technology Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States); Institute for Molecular Engineering, The University of Chicago, 5747 South Ellis Avenue, Chicago, Illinois 60637 (United States); Department of Chemical and Environmental Engineering, School of Engineering and Applied Science, Yale University, 9 Hillhouse Avenue, New Haven, Connecticut 06520 (United States)

2014-05-07T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Plasma-assisted catalytic storage reduction system  

DOE Patents [OSTI]

A two-stage method for NO.sub.x reduction in an oxygen-rich engine exhaust comprises a plasma oxidative stage and a storage reduction stage. The first stage employs a non-thermal plasma treatment of NO.sub.x gases in an oxygen-rich exhaust and is intended to convert NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons. The second stage employs a lean NO.sub.x trap to convert such NO.sub.2 to environmentally benign gases that include N.sub.2, CO.sub.2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage with a plasma, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber in which a non-thermal plasma converts NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons, such as propene. A flow of such hydrocarbons (C.sub.x H.sub.y) is input from usually a second pipe into at least a portion of the first chamber. The NO.sub.2 from the plasma treatment proceeds to a storage reduction catalyst (lean NO.sub.x trap) that converts NO.sub.2 to N.sub.2, CO.sub.2, and H.sub.2 O, and includes a nitrate-forming catalytic site. The hydrocarbons and NO.sub.x are simultaneously reduced while passing through the lean-NO.sub.x trap catalyst. The method allows for enhanced NO.sub.x reduction in vehicular engine exhausts, particularly those having relatively high sulfur contents.

Penetrante, Bernardino M. (San Ramon, CA); Vogtlin, George E. (Fremont, CA); Merritt, Bernard T. (Livermore, CA); Brusasco, Raymond M. (Livermore, CA)

2002-01-01T23:59:59.000Z

242

Plasma-assisted catalytic storage reduction system  

DOE Patents [OSTI]

A two-stage method for NO.sub.x reduction in an oxygen-rich engine exhaust comprises a plasma oxidative stage and a storage reduction stage. The first stage employs a non-thermal plasma treatment of NO.sub.x gases in an oxygen-rich exhaust and is intended to convert NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons. The second stage employs a lean NO.sub.x trap to convert such NO.sub.2 to environmentally benign gases that include N.sub.2, CO.sub.2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage with a plasma, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber in which a non-thermal plasma converts NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons, such as propene. A flow of such hydrocarbons (C.sub.x H.sub.y) is input from usually a second pipe into at least a portion of the first chamber. The NO.sub.2 from the plasma treatment proceeds to a storage reduction catalyst (lean NO.sub.x trap) that converts NO.sub.2 to N.sub.2, CO.sub.2, and H.sub.2 O, and includes a nitrate-forming catalytic site. The hydrocarbons and NO.sub.x are simultaneously reduced while passing through the lean-NO.sub.x trap catalyst. The method allows for enhanced NO.sub.x reduction in vehicular engine exhausts, particularly those having relatively high sulfur contents.

Penetrante, Bernardino M. (San Ramon, CA); Vogtlin, George E. (Fremont, CA); Merritt, Bernard T. (Livermore, CA); Brusasco, Raymond M. (Livermore, CA)

2000-01-01T23:59:59.000Z

243

Synthesis and characterization of supported heteropolymolybdate nanoparticles between silicate layers of Bentonite with enhanced catalytic activity for epoxidation of alkenes  

SciTech Connect (OSTI)

Highlights: {yields} The PVMo and nanocomposite catalyst (PVMo/Bentonite) as catalyst for epoxidation of alkenes. {yields} The composite catalyst showed higher catalytic activity than parent heteropolymolybdate (PVMo). {yields}The use of ultrasonic irradiation increased the conversions and reduced the reaction times. {yields} The H{sub 2}O{sub 2} is a green and eco-friendly oxidant in this catalytic system. -- Abstract: A new heterogeneous catalyst (PVMo/Bentonite) consisting of vanadium substituted heteropolymolybdate with Keggin-type structure Na{sub 5}[PV{sub 2}Mo{sub 10}O{sub 40}].14H{sub 2}O (PVMo) supported between silicate layers of bentonite has been synthesized by impregnation method and characterized using X-ray diffraction, Fourier-transformed infrared spectroscopy, scanning electron microscopy, UV-vis diffuse reflectance spectroscopy, transmission electron microscopy and elemental analysis. X-ray diffraction and scanning electron microscopy analysis indicated that PVMo was finely dispersed into layers of bentonite as support. The PVMo/Bentonite used as an efficient heterogeneous catalyst for epoxidation of alkenes. Various cyclic and linear alkenes were oxidized into the corresponding epoxides in high yields and selectivity with 30% aqueous H{sub 2}O{sub 2}. The catalyst was reused several times, without observable loss of activity and selectivity. The obtained results showed that the catalytic activity of the PVMo/Bentonite was higher than that of pure heteropolyanion (PVMo).

Salavati, Hossein, E-mail: hosseinsalavati@yahoo.com [Department of Chemistry, Payame Noor University (PNU), 19395-4697, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of)] [Department of Chemistry, Payame Noor University (PNU), 19395-4697, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of); Rasouli, Nahid [Department of Chemistry, Payame Noor University (PNU), 19395-4697, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of)] [Department of Chemistry, Payame Noor University (PNU), 19395-4697, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of)

2011-11-15T23:59:59.000Z

244

Synthesis and Characterization of Metal Complexes to be Employed in the Catalytic Depolymerization of Lignin Model Compounds  

SciTech Connect (OSTI)

Lignin is an earth-abundant biopolymer that is grossly underutilized as a value stream in current biomass conversion technologies because there exist no economic and technically feasible routes for lignin depolymerization and upgrading to fuels and chemicals. The development of new mild and selective catalytic routes to depolymerize this recalcitrant biopolymer is required to more effectively utilize lignin. To that end, our group aims to synthesize and characterize a collection of organometallic catalysts to promote atom-economical catalytic lignin deconstruction. These catalysts have been screened against dimeric lignin model compounds in order to gain mechanistic insights into their modes of action. In addition, experimental efforts have been coupled with quantum mechanical calculations to elucidate solution behavior of the catalysts as well as the mechanisms of lignin depolymerization. Detailed synthetic procedures, as well as spectroscopic and crystallographic characterization and DFT calculations will be presented.

Chmely, S. C.; Kim, S.; Beckham, G. T.

2012-01-01T23:59:59.000Z

245

Ultra Low NOx Catalytic Combustion for IGCC Power Plants  

SciTech Connect (OSTI)

In order to meet DOE's goals of developing low-emissions coal-based power systems, PCI has further developed and adapted it's Rich-Catalytic Lean-burn (RCL{reg_sign}) catalytic reactor to a combustion system operating on syngas as a fuel. The technology offers ultra-low emissions without the cost of exhaust after-treatment, with high efficiency (avoidance of after-treatment losses and reduced diluent requirements), and with catalytically stabilized combustion which extends the lower Btu limit for syngas operation. Tests were performed in PCI's sub-scale high-pressure (10 atm) test rig, using a two-stage (catalytic then gas-phase) combustion process for syngas fuel. In this process, the first stage consists of a fuel-rich mixture reacting on a catalyst with final and excess combustion air used to cool the catalyst. The second stage is a gas-phase combustor, where the air used for cooling the catalyst mixes with the catalytic reactor effluent to provide for final gas-phase burnout and dilution to fuel-lean combustion products. During testing, operating with a simulated Tampa Electric's Polk Power Station syngas, the NOx emissions program goal of less than 0.03 lbs/MMBtu (6 ppm at 15% O{sub 2}) was met. NOx emissions were generally near 0.01 lbs/MMBtu (2 ppm at 15% O{sub 2}) (PCI's target) over a range on engine firing temperatures. In addition, low emissions were shown for alternative fuels including high hydrogen content refinery fuel gas and low BTU content Blast Furnace Gas (BFG). For the refinery fuel gas increased resistance to combustor flashback was achieved through preferential consumption of hydrogen in the catalytic bed. In the case of BFG, stable combustion for fuels as low as 88 BTU/ft{sup 3} was established and maintained without the need for using co-firing. This was achieved based on the upstream catalytic reaction delivering a hotter (and thus more reactive) product to the flame zone. The PCI catalytic reactor was also shown to be active in ammonia reduction in fuel allowing potential reductions in the burner NOx production. These reductions of NOx emissions and expanded alternative fuel capability make the rich catalytic combustor uniquely situated to provide reductions in capital costs through elimination of requirements for SCR, operating costs through reduction in need for NOx abating dilution, SCR operating costs, and need for co-firing fuels allowing use of lower value but more available fuels, and efficiency of an engine through reduction in dilution flows.

Shahrokh Etemad; Benjamin Baird; Sandeep Alavandi; William Pfefferle

2008-03-31T23:59:59.000Z

246

Method for measuring recovery of catalytic elements from fuel cells  

DOE Patents [OSTI]

A method is provided for measuring the concentration of a catalytic clement in a fuel cell powder. The method includes depositing on a porous substrate at least one layer of a powder mixture comprising the fuel cell powder and an internal standard material, ablating a sample of the powder mixture using a laser, and vaporizing the sample using an inductively coupled plasma. A normalized concentration of catalytic element in the sample is determined by quantifying the intensity of a first signal correlated to the amount of catalytic element in the sample, quantifying the intensity of a second signal correlated to the amount of internal standard material in the sample, and using a ratio of the first signal intensity to the second signal intensity to cancel out the effects of sample size.

Shore, Lawrence (Edison, NJ); Matlin, Ramail (Berkeley, NJ)

2011-03-08T23:59:59.000Z

247

Imaging Catalytic Surfaces by Multiplexed Capillary Electrophoresis With Absorption Detection  

SciTech Connect (OSTI)

A new technique for in situ imaging and screening heterogeneous catalysts by using multiplexed capillary electrophoresis with absorption detection was developed. By bundling the inlets of a large number of capillaries, an imaging probe can be created that can be used to sample products formed directly from a catalytic surface with high spatial resolution. In this work, they used surfaces made of platinum, iron or gold wires as model catalytic surfaces for imaging. Various shapes were recorded including squares and triangles. Model catalytic surfaces consisting of both iron and platinum wires in the shape of a cross were also imaged successfully. Each of the two wires produced a different electrochemical product that was separated by capillary electrophoresis. Based on the collected data they were able to distinguish the products from each wire in the reconstructed image.

Michael Christodoulou

2002-08-27T23:59:59.000Z

248

Fuel Flexible, Low Emission Catalytic Combustor for Opportunity Fuel Applications  

SciTech Connect (OSTI)

Limited fuel resources, increasing energy demand and stringent emission regulations are drivers to evaluate process off-gases or process waste streams as fuels for power generation. Often these process waste streams have low energy content and/or highly reactive components. Operability of low energy content fuels in gas turbines leads to issues such as unstable and incomplete combustion. On the other hand, fuels containing higher-order hydrocarbons lead to flashback and auto-ignition issues. Due to above reasons, these fuels cannot be used directly without modifications or efficiency penalties in gas turbine engines. To enable the use of these wide variety of fuels in gas turbine engines a rich catalytic lean burn (RCL®) combustion system was developed and tested in a subscale high pressure (10 atm.) rig. The RCL® injector provided stability and extended turndown to low Btu fuels due to catalytic pre-reaction. Previous work has shown promise with fuels such as blast furnace gas (BFG) with LHV of 85 Btu/ft3 successfully combusted. This program extends on this work by further modifying the combustor to achieve greater catalytic stability enhancement. Fuels containing low energy content such as weak natural gas with a Lower Heating Value (LHV) of 6.5 MJ/m3 (180 Btu/ft3 to natural gas fuels containing higher hydrocarbon (e.g ethane) with LHV of 37.6 MJ/m3 (1010 Btu/ft3) were demonstrated with improved combustion stability; an extended turndown (defined as the difference between catalytic and non-catalytic lean blow out) of greater than 250oF was achieved with CO and NOx emissions lower than 5 ppm corrected to 15% O2. In addition, for highly reactive fuels the catalytic region preferentially pre-reacted the higher order hydrocarbons with no events of flashback or auto-ignition allowing a stable and safe operation with low NOx and CO emissions.

Eteman, Shahrokh

2013-06-30T23:59:59.000Z

249

Catalytic conversion of light alkanes. Final report, January 1, 1990--October 31, 1994  

SciTech Connect (OSTI)

During the course of the first three years of the Cooperative Agreement (Phase I-III), we uncovered a family of metal perhaloporphyrin complexes which had unprecedented activity for the selective air-oxidation of fight alkanes to alcohols. The reactivity of fight hydrocarbon substrates with air or oxygen was in the order: isobutane>propane>ethane>methane, in accord with their homolytic bond dissociation energies. Isobutane was so reactive that the proof-of concept stage of a process for producing tert-butyl alcohol from isobutane was begun (Phase V). It was proposed that as more active catalytic systems were developed (Phases IV, VI), propane, then ethane and finally methane oxidations will move into this stage (Phases VII through IX). As of this writing, however, the program has been terminated during the later stages of Phases V and VI so that further work is not anticipated. We made excellent progress during 1994 in generating a class of less costly new materials which have the potential for high catalytic activity. New routes were developed for replacing costly perfluorophenyl groups in the meso-position of metalloporphyrin catalysts with far less expensive and lower molecular weight perfluoromethyl groups.

NONE

1998-12-31T23:59:59.000Z

250

Catalytic process for control of NOx emissions using hydrogen  

DOE Patents [OSTI]

A selective catalytic reduction process with a palladium catalyst for reducing NOx in a gas, using hydrogen as a reducing agent. A zirconium sulfate (ZrO2)SO4 catalyst support material with about 0.01-2.0 wt. % Pd is applied to a catalytic bed positioned in a flow of exhaust gas at about 70-200.degree. C. The support material may be (ZrO2--SiO2)SO4. H2O and hydrogen may be injected into the exhaust gas upstream of the catalyst to a concentration of about 15-23 vol. % H2O and a molar ratio for H2/NOx in the range of 10-100. A hydrogen-containing fuel may be synthesized in an Integrated Gasification Combined Cycle power plant for combustion in a gas turbine to produce the exhaust gas flow. A portion of the fuel may be diverted for the hydrogen injection.

Sobolevskiy, Anatoly; Rossin, Joseph A.; Knapke, Michael J.

2010-05-18T23:59:59.000Z

251

Recent developments in the production of liquid fuels via catalytic conversion of microalgae: experiments and simulations  

SciTech Connect (OSTI)

Due to continuing high demand, depletion of non-renewable resources and increasing concerns about climate change, the use of fossil fuel-derived transportation fuels faces relentless challenges both from a world markets and an environmental perspective. The production of renewable transportation fuel from microalgae continues to attract much attention because of its potential for fast growth rates, high oil content, ability to grow in unconventional scenarios, and inherent carbon neutrality. Moreover, the use of microalgae would minimize ‘‘food versus fuel’’ concerns associated with several biomass strategies, as microalgae do not compete with food crops in the food chain. This paper reviews the progress of recent research on the production of transportation fuels via homogeneous and heterogeneous catalytic conversions of microalgae. This review also describes the development of tools that may allow for a more fundamental understanding of catalyst selection and conversion processes using computational modelling. The catalytic conversion reaction pathways that have been investigated are fully discussed based on both experimental and theoretical approaches. Finally, this work makes several projections for the potential of various thermocatalytic pathways to produce alternative transportation fuels from algae, and identifies key areas where the authors feel that computational modelling should be directed to elucidate key information to optimize the process.

Shi,Fan; Wang, Pin; Duan, Yuhua; Link, Dirk; Morreale, Bryan

2012-01-01T23:59:59.000Z

252

5 Hz Catalytic Emissions FT-IR Monitoring during Lean-Rich Engine...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Hz Catalytic Emissions FT-IR Monitoring during Lean-Rich Engine Cycles: Comparison to Reference Methods 5 Hz Catalytic Emissions FT-IR Monitoring during Lean-Rich Engine Cycles:...

253

Bioenergy Technologies Office R&D Pathways: In-Situ Catalytic...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Office R&D Pathways: In-Situ Catalytic Fast Pyrolysis The in-situ catalytic fast pyrolysis pathway involves rapidly heating biomass with a catalyst to create bio-oils,...

254

Bioenergy Technologies Office R&D Pathways: Ex-Situ Catalytic...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Office R&D Pathways: Ex-Situ Catalytic Fast Pyrolysis In ex-situ catalytic fast pyrolysis, biomass is heated with catalysts to create bio-oils, which are then used to...

255

Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine  

E-Print Network [OSTI]

As part of the MIT micro-gas turbine engine project, the development of a hydrocarbon-fueled catalytic micro-combustion system is presented. A conventionally-machined catalytic flow reactor was built to simulate the ...

Peck, Jhongwoo, 1976-

2003-01-01T23:59:59.000Z

256

Model catalytic studies of single crystal, polycrystalline metal, and supported catalysts  

E-Print Network [OSTI]

This dissertation is focused on understanding the structure-activity relationship in heterogeneous catalysis by studying model catalytic systems. The catalytic oxidation of CO was chosen as a model reaction for studies on a variety of catalysts. A...

Yan, Zhen

2009-05-15T23:59:59.000Z

257

Continued investigations of the catalytic reduction of N? to NH? by molybdenum triamidoamine complexes  

E-Print Network [OSTI]

A study of the effects of employing different solvents and the introduction of dihydrogen during the catalytic reduction of dinitrogen to ammonia with [HIPTN 3N]Mo complexes was completed. During a catalytic reaction, the ...

Hanna, Brian S. (Brian Stewart)

2011-01-01T23:59:59.000Z

258

Methods of using structures including catalytic materials disposed within porous zeolite materials to synthesize hydrocarbons  

DOE Patents [OSTI]

Catalytic structures include a catalytic material disposed within a zeolite material. The catalytic material may be capable of catalyzing a formation of methanol from carbon monoxide and/or carbon dioxide, and the zeolite material may be capable of catalyzing a formation of hydrocarbon molecules from methanol. The catalytic material may include copper and zinc oxide. The zeolite material may include a first plurality of pores substantially defined by a crystal structure of the zeolite material and a second plurality of pores dispersed throughout the zeolite material. Systems for synthesizing hydrocarbon molecules also include catalytic structures. Methods for synthesizing hydrocarbon molecules include contacting hydrogen and at least one of carbon monoxide and carbon dioxide with such catalytic structures. Catalytic structures are fabricated by forming a zeolite material at least partially around a template structure, removing the template structure, and introducing a catalytic material into the zeolite material.

Rollins, Harry W. (Idaho Falls, ID); Petkovic, Lucia M. (Idaho Falls, ID); Ginosar, Daniel M. (Idaho Falls, ID)

2011-02-01T23:59:59.000Z

259

Advanced byproduct recovery: Direct catalytic reduction of sulfur dioxide to elemental sulfur. Fourth quarterly technical progress report  

SciTech Connect (OSTI)

The team of Arthur D. Little, Tufts University and Engelhard Corporation are conducting Phase 1 of a four and a half year, two-phase effort to develop and scale-up an advanced byproduct recovery technology that is a direct, single-stage, catalytic process for converting sulfur dioxide to elemental sulfur. This catalytic process reduces SO{sub 2} over a fluorite-type oxide (such as ceria and zirconia). The catalytic activity can be significantly promoted by active transition metals, such as copper. More than 95% elemental sulfur yield, corresponding to almost complete sulfur dioxide conversion, was obtained over a Cu-Ce-O oxide catalyst as part of an on-going DOE-sponsored, University Coal Research Program. This type of mixed metal oxide catalyst has stable activity, high selectivity for sulfur production, and is resistant to water and carbon dioxide poisoning. Tests with CO and CH{sub 4} reducing gases indicate that the catalyst has the potential for flexibility with regard to the composition of the reducing gas, making it attractive for utility use. The performance of the catalyst is consistently good over a range of SO{sub 2} inlet concentration (0.1 to 10%) indicating its flexibility in treating SO{sub 2} tail gases as well as high concentration streams.

NONE

1997-01-01T23:59:59.000Z

260

In-Situ Catalytic Fast Pyrolysis Technology Pathway  

SciTech Connect (OSTI)

This technology pathway case investigates converting woody biomass using in-situ catalytic fast pyrolysis followed by upgrading to gasoline-, diesel-, and jet-range hydrocarbon blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

Biddy, M.; Dutta, A.; Jones, S.; Meyer, A.

2013-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Ex-Situ Catalytic Fast Pyrolysis Technology Pathway  

SciTech Connect (OSTI)

This technology pathway case investigates converting woody biomass using ex-situ catalytic fast pyrolysis followed by upgrading to gasoline-, diesel-, and jet-range hydrocarbon blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

Biddy, M.; Dutta, A.; Jones, S.; Meyer, A.

2013-03-01T23:59:59.000Z

262

Short Communication Catalytic coal gasification: use of calcium versus potassium*  

E-Print Network [OSTI]

Short Communication Catalytic coal gasification: use of calcium versus potassium* Ljubisa R on the gasification in air and 3.1 kPa steam of North Dakota lignitic chars prepared under slow and rapid pyrolysis of calcium is related to its sintering via crystallite growth. (Keywords: coal; gasification; catalysis

263

Catalytic, Enantioselective Alkylations of N,O-Acetals  

E-Print Network [OSTI]

, 10998-10999. (2) Hoveyda et al. have developed a Ni-catalyzed alkylation reaction of allylic acetalsCatalytic, Enantioselective Alkylations of N,O-Acetals Dana Ferraris, Travis Dudding, Brandon Young alkylation reactions of acetals have attained a prominent position in organic synthesis.1 Methods employing

Lectka, Thomas

264

Catalytic Asymmetric Synthesis of Hydroxy Enol Ethers: Approach to a  

E-Print Network [OSTI]

for the generation of polypro- pionate backbone.1-7 In contrast, the asymmetric acetate aldol reaction that leads associated with acetate aldol reactions have prompted investigations into alternative methods to generate the catalytic asymmetric allylation of aldehydes followed by oxidative cleavage of the allyl group (Scheme 1, A

Walsh, Patrick J.

265

Scaling behavior of optimally structured catalytic microfluidic reactors  

E-Print Network [OSTI]

In this study of catalytic microfluidic reactors we show that, when optimally structured, these reactors share underlying scaling properties. The scaling is predicted theoretically and verified numerically. Furthermore, we show how to increase the reaction rate significantly by distributing the active porous material within the reactor using a high-level implementation of topology optimization.

Okkels, F; Bruus, Henrik; Okkels, Fridolin

2006-01-01T23:59:59.000Z

266

Structural Dynamics of a Catalytic Monolayer Probed by Ultrafast  

E-Print Network [OSTI]

REPORTS Structural Dynamics of a Catalytic Monolayer Probed by Ultrafast 2D IR Vibrational Echoes in solutions. Here, we extend the technique to probing the interfacial dynamics and structure of a silica. The structural dynamics, as reported on by a carbonyl stretch vibration of the surface-bound complex, have

Fayer, Michael D.

267

Nanostructured Molybdenum Carbide: Sonochemical Synthesis and Catalytic Properties  

E-Print Network [OSTI]

to be a useful technique to generate nanophase transition metals.7,8 Recently, molybdenum and tungsten carbides of metal salts.5,6 Sonochemical decomposition of transition metal carbonyl compounds has also been provenNanostructured Molybdenum Carbide: Sonochemical Synthesis and Catalytic Properties Taeghwan Hyeon

Suslick, Kenneth S.

268

The Biodiversity of Catalytic Super-Brownian Motion Klaus Fleischmann  

E-Print Network [OSTI]

The Biodiversity of Catalytic Super-Brownian Motion Klaus Fleischmann WeierstraÃ?-Institut f that the reactant has an infinite local biodiversity or genetic abundance. This contrasts the finite local biodiversity of the equilibrium of classical super-Brownian motion. Another question we address

Klenke, Achim

269

Catalytic Methane Reduction in the Exhaust Gas of Combustion Engines  

E-Print Network [OSTI]

Catalytic Methane Reduction in the Exhaust Gas of Combustion Engines Peter Mauermann1,* , Michael Dornseiffer6 , Frank Amkreutz6 1 Institute for Combustion Engines , RWTH Aachen University, Schinkelstr. 8, D of the hydrocarbon exhaust of internal combustion engines. In contrast to other gaseous hydrocarbons, significant

Dunin-Borkowski, Rafal E.

270

Catalytic Domain of Phosphoinositide-specific Phospholipase C (PLC)  

E-Print Network [OSTI]

Catalytic Domain of Phosphoinositide-specific Phospholipase C (PLC) MUTATIONAL ANALYSIS OF RESIDUES WITHIN THE ACTIVE SITE AND HYDROPHOBIC RIDGE OF PLC 1* (Received for publication, November 20, 1997 Institute, University of Dundee, Dundee DD1 4HN, United Kingdom Structural studies of phospholipase C 1 (PLC

Williams, Roger L.

271

Task 3.9 -- Catalytic tar cracking. Semi-annual report, January 1--June 30, 1995  

SciTech Connect (OSTI)

Tar produced in the gasification of coal is deleterious to the operation of downstream equipment including fuel cells, gas turbines, hot-gas stream cleanup filters, and pressure swing adsorption systems. Catalytic cracking of tars to smaller hydrocarbons can be an effective means to remove these tars from gas streams and, in the process, generate useful products, e.g., methane gas, which is crucial to the operation of molten carbonate fuel cells. The objectives of this project are to investigate whether gasification tars can be cracked by synthetic nickel-substituted micamontmorillonite, zeolite, or dolomite material; and whether the tars can be cracked selectively by these catalysts to produce a desired liquid and/or gas stream. Results to date are presented in the cited papers.

Young, B.C.; Timpe, R.C.

1995-12-31T23:59:59.000Z

272

Catalytic reactive separation system for energy-efficient production of cumene  

DOE Patents [OSTI]

The present invention relates to an atmospheric pressure, reactive separation column packed with a solid acid zeolite catalyst for producing cumene from the reaction of benzene with propylene. Use of this un-pressurized column, where simultaneous reaction and partial separation occur during cumene production, allow separation of un-reacted, excess benzene from other products as they form. This high-yielding, energy-efficient system allows for one-step processing of cumene, with reduced need for product purification. Reacting propylene and benzene in the presence of beta zeolite catalysts generated a selectivity greater than 85% for catalytic separation reactions at a reaction temperature of 115 degrees C and at ambient pressure. Simultaneously, up to 76% of un-reacted benzene was separated from the product; which could be recycled back to the reactor for re-use.

Buelna, Genoveva (Nuevo Laredo, MX); Nenoff, Tina M. (Albuquerque, NM)

2009-07-28T23:59:59.000Z

273

Interacting FisherWright Diffusions in a Catalytic Medium Andreas Greven  

E-Print Network [OSTI]

environment (catalytic medium). Here we introduce a model of interacting Fisher­Wright diffusions where environment, catalytic medium, longtime behaviour, rescaling. AMS Subject Classification: 60K35, 60J70Interacting Fisher­Wright Diffusions in a Catalytic Medium Andreas Greven Mathematisches Institut

Klenke, Achim

274

Industrial Gas Turbine Engine Catalytic Pilot Combustor-Prototype Testing  

SciTech Connect (OSTI)

PCI has developed and demonstrated its Rich Catalytic Lean-burn (RCL®) technology for industrial and utility gas turbines to meet DOEâ??s goals of low single digit emissions. The technology offers stable combustion with extended turndown allowing ultra-low emissions without the cost of exhaust after-treatment and further increasing overall efficiency (avoidance of after-treatment losses). The objective of the work was to develop and demonstrate emission benefits of the catalytic technology to meet strict emissions regulations. Two different applications of the RCL® concept were demonstrated: RCL® catalytic pilot and Full RCL®. The RCL® catalytic pilot was designed to replace the existing pilot (a typical source of high NOx production) in the existing Dry Low NOx (DLN) injector, providing benefit of catalytic combustion while minimizing engine modification. This report discusses the development and single injector and engine testing of a set of T70 injectors equipped with RCL® pilots for natural gas applications. The overall (catalytic pilot plus main injector) program NOx target of less than 5 ppm (corrected to 15% oxygen) was achieved in the T70 engine for the complete set of conditions with engine CO emissions less than 10 ppm. Combustor acoustics were low (at or below 0.1 psi RMS) during testing. The RCL® catalytic pilot supported engine startup and shutdown process without major modification of existing engine controls. During high pressure testing, the catalytic pilot showed no incidence of flashback or autoignition while operating over a wide range of flame temperatures. In applications where lower NOx production is required (i.e. less than 3 ppm), in parallel, a Full RCL® combustor was developed that replaces the existing DLN injector providing potential for maximum emissions reduction. This concept was tested at industrial gas turbine conditions in a Solar Turbines, Incorporated high-pressure (17 atm.) combustion rig and in a modified Solar Turbines, Incorporated Saturn engine rig. High pressure single-injector rig and modified engine rig tests demonstrated NOx less than 2 ppm and CO less than 10 ppm over a wide flame temperature operating regime with low combustion noise (<0.15% peak-to-peak). Minimum NOx for the optimized engine retrofit Full RCL® designs was less than 1 ppm with CO emissions less than 10 ppm. Durability testing of the substrate and catalyst material was successfully demonstrated at pressure and temperature showing long term stable performance of the catalytic reactor element. Stable performance of the reactor element was achieved when subjected to durability tests (>5000 hours) at simulated engine conditions (P=15 atm, Tin=400C/750F.). Cyclic tests simulating engine trips was also demonstrated for catalyst reliability. In addition to catalyst tests, substrate oxidation testing was also performed for downselected substrate candidates for over 25,000 hours. At the end of the program, an RCL® catalytic pilot system has been developed and demonstrated to produce NOx emissions of less than 3 ppm (corrected to 15% O2) for 100% and 50% load operation in a production engine operating on natural gas. In addition, a Full RCL® combustor has been designed and demonstrated less than 2 ppm NOx (with potential to achieve 1 ppm) in single injector and modified engine testing. The catalyst/substrate combination has been shown to be stable up to 5500 hrs in simulated engine conditions.

Shahrokh Etemad; Benjamin Baird; Sandeep Alavandi; William Pfefferle

2009-09-30T23:59:59.000Z

275

Reaction network and kinetics for the catalytic oxidation of toluene over V sub 2 O sub 5  

SciTech Connect (OSTI)

The oxidation of three methyl-diphenylmethane isomers and of bibenzyl, benzyl alcohol, and benzaldehyde, which are intermediates in the catalytic oxidation of toluene over V{sub 2}O{sub 5}, has been studied to elucidate the reaction network and relative importance of various reactions. Selectivity dependences reveal that the network is composed mainly of three parallel reaction routes: (1) side-chain oxidation with consecutive reactions, (2) oxidative coupling with both parallel and consecutive reactions, and (3) carbon oxide formation. Coupling products are not negligible, with an initial selectivity of 29% (400{degree}C). Anthraquinone is produced mainly from o-methyl-diphenylmethane conditions and catalyst used. Selectivity dependences suggested product lumping and a simplified network. Kinetic analysis of this reaction network indicates that higher temperatures favor route 2 over route 1. The same initial intermediates for route 1 of side-chain oxidation and for route 2 of oxidative coupling are suggested.

Zhu, J.; Andersson, L.T. (Univ. of Lund (Sweden))

1990-11-01T23:59:59.000Z

276

Final Report, "Molecular Design of Hydrocarbon Oxidation Catalytic Processes"  

SciTech Connect (OSTI)

The main goal of this project had been to use model systems to correlate selectivities in partial oxidation catalysis with the presence of specific sites on the surface of the catalyst. Extensive work was performed this year on characterizing oxygen-treated nickel surfaces by chemical means. Specifically, the surface chemistry of ammonia coadsorbed with atomic oxygen on Ni(110) single-crystal surfaces was studied by temperature-programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS). It was determined that at intermediate oxygen coverages direct ammonia adsorption on nickel sites is suppressed, but a new high-temperature reaction regime is generated at 400 K where NHx surface fragments are rehydrogenated concurrently with the production of water and molecular hydrogen. The extensive isotope scrambling and hydrogen transfer seen from nitrogen- to oxygen-containing surface intermediates, and the optimum yields seen for this 400 K state at intermediate oxygen coverages, strongly suggest the direct interaction of the adsorbed ammonia with oxygen atoms at the end of the –Ni–O- rows that form upon reconstruction of the surface. Hydrogen transfer between ammonia and oxygen appears to take place directly via hydrogen bonding, and to be reversible but biased towards water formation. An equilibrium is reached between the produced water and the reacting surface oxygen and hydrogen. The strong influence of the OH surface groups on the thermal chemistry of the adsorbed ammonia was interpreted in terms of the adsorbing geometry of the OH groups on the surface, and of hydrogen bonding between adsorbed OH and NH3 species. In terms of alcohol reactivity, the adsorption of 2-iodoethanol, a precursor for the preparation of 2-hydroxyethyl and oxametallacycle surface species, was found to lead to two configurations involving either just the iodine atom or both iodine and hydroxyl ends of the molecule. A complex chemical behavior starts around 140 K with the production of small amounts of ethylene and water, most likely via the concerted decomposition or disproportionation of the adsorbed molecular species. The bulk of the 2-iodoethanol decomposes at about 150 K via an initial carbon-iodine scission to form –O(H)CH2CH2– (~80%) and 2-hydroxyethyl (~20%) intermediates. Two competing reactions are involved with the subsequent conversion of the 2-hydroxyethyl species around 160 K, a reductive elimination with surface hydrogen to yield ethanol, and a ?-H elimination to surface vinyl alcohol. The –O(H)CH2CH2–, on the other hand, dehydrogenates to a –OCH2CH2– oxametallacycle species about the same temperature. Both 2-hydroxyethyl and oxametallacycle species tautomerize to acetaldehyde, around 210 K and above 250 K, respectively, and some of that acetaldehyde desorbs while the rest decomposes to hydrogen and carbon monoxide. We contend that a better understanding of the surface chemistry of oxygen-containing surfaces can lead to better selectivities in catalysis. This is arguably the most important issue in the field of catalysis in the near future, and one that impacts several technologies of interest to DOE such as the manufacturing of speciality chemicals and the control and removal of pollutants. Additional work was performed on the characterization of the chemistry of methyl and methylene adsorbed species on oxygen-treated nickel surfaces. Complex chemistry was observed involving not only hydrogenation and dehydrogenation steps, but also C-C couplings and methylene insertions to produce heavier hydrocarbons, and oxygen insertion reactions that yield oxygenates. Finally, a dual titration technique employing xenon and a chemically sensitive probe was developed to identify minority catalytic sites on oxide surfaces. In the case of oxygen-treated Ni(110) single crystals, it was found that both hydrogen transfer with adsorbed water or ammonia and certain hydrocarbon hydrogenation reactions take place at the end of the –Ni–O rows that form in this system. Carbon and nitrogen oxides, on the other hand, display no pre

Professor Francisco Zaera

2007-08-09T23:59:59.000Z

277

Retarded Interaction of Electromagnetic field and Symmetry Violation of Time Reversal in Non-linear Optics  

E-Print Network [OSTI]

Based on Document (1), by considering the retarded interaction of radiation fields, the third order transition probabilities of stimulated radiations and absorptions of light are calculated. The revised formulas of nonlinear polarizations are provided. The results show that that the general processes of non-linear optics violate time reversal symmetry. The phenomena of non-linear optics violating time reversal symmetry just as sum frequency, double frequency, different frequencies, double stable states, self-focusing and self-defocusing, echo phenomena, as well as optical self-transparence and self absorptions and so on are analyzed.

Mei Xiaochun

2008-04-19T23:59:59.000Z

278

Synthesis gas formation by catalytic oxidation of methane in fluidized bed reactors  

SciTech Connect (OSTI)

The production of synthesis gas (CO + H[sub 2]) by the catalytic partial oxidation of CH[sub 4] in air or O[sub 2] in static fluidized beds at atmospheric pressure has been examined over Pt, Rh, and Ni catalysts coated on 100-[mu]m [alpha]-Al[sub 2]O[sub 3] beads. With CH[sub 4]/air feeds, CO and H[sub 2] selectivities as high as 95% with >90% CH[sub 4] conversion were obtained on Rh and Ni catalysts at contact times of 0.1-0.5 sec. Pt catalysts were found to have significantly lower selectivities for all the three catalysts were improved by heating the reaction mixture above the autothermal reactor temperature and using O[sub 2] instead of air. The selectivities and conversions were fairly constant over the range of contact time s used. Probable reaction pathways for CH[sub 4] oxidation in fluidized beds are discussed. 31 refs., 6 figs.

Bharadwaj, S.S.; Schmidt, L.D. (Univ. of Minnesota, Minneapolis (United States))

1994-03-01T23:59:59.000Z

279

Method for recovering catalytic elements from fuel cell membrane electrode assemblies  

DOE Patents [OSTI]

A method for recovering catalytic elements from a fuel cell membrane electrode assembly is provided. The method includes converting the membrane electrode assembly into a particulate material, wetting the particulate material, forming a slurry comprising the wetted particulate material and an acid leachate adapted to dissolve at least one of the catalytic elements into a soluble catalytic element salt, separating the slurry into a depleted particulate material and a supernatant containing the catalytic element salt, and washing the depleted particulate material to remove any catalytic element salt retained within pores in the depleted particulate material.

Shore, Lawrence (Edison, NJ); Matlin, Ramail (Berkeley Heights, NJ); Heinz, Robert (Ludwigshafen, DE)

2012-06-26T23:59:59.000Z

280

Essential Characteristics of Self-Determined Beahvior of Individuals with Mental Retardation  

E-Print Network [OSTI]

., Park-Lee, S., & Meyer, L (1988). Daily decision-making in community residences: A social comparison of adults with and without mental retardation. American journal on Mental Retardation, 92, 430-435. Martin, J. E., & Marshall, L. H. (1995...G54G6FG70G69G63G3AG20G53G65G6CG66G2DG44G65G74G65G72G6DG69G6EG61G74G69G6FG6E G42G4FG54G54G4FG4DG20G20G4CG49G4EG45 G54G49G50G53 G57G65G68G6DG65G79G65G72G2CG20G4DG2EG20G4CG2EG2CG20G4BG65G6CG63G68G6EG65G72G2CG20G4BG2EG2CG20G26G20G52G69G63G68G61G72G64G73...

Wehmeyer, Michael L.; Kelchner, Kathy; Richards, Sandy

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

A low-voltage retarding-field Mott polarimeter for photocathode characterization  

SciTech Connect (OSTI)

Nuclear physics experiments at Thomas Jefferson National Accelerator Facility's CEBAF rely on high polarization electron beams. We describe a recently commissioned system for prequalifying and studying photocathodes for CEBAF with a load-locked, low-voltage polarized electron source coupled to a compact retarding-field Mott polarimeter. The polarimeter uses simplified electrode structures and operates from 5 to 30 kV. The effective Sherman function for this device has been calibrated by comparison with the CEBAF 5 MeV Mott polarimeter. For elastic scattering from a thick gold target at 20 keV, the effective Sherman function is 0.201(5). Its maximum efficiency at 20 keV, defined as the detected count rate divided by the incident particle current, is 5.4(2)×10?4, yielding a figure-of-merit, or analyzing power squared times efficiency, of 1.0(1)×10?5. The operating parameters of this new polarimeter design are compared to previously published data for other compact Mott polarimeters of the retarding-field type.

J.L. McCarter, M.L. Stutzman, K.W. Trantham, T.G. Anderson, A.M. Cook, T.J. Gay

2010-06-01T23:59:59.000Z

282

Development of flame retardant PV module encapsulants: Volume 1. Final report  

SciTech Connect (OSTI)

This Phase 1 final report covers the work performed by Springborn Testing and Research, Inc., for the period October 1, 1997 to June 30, 1998 under the Department of Energy Cooperative Agreement Number DE-FC36-97GO10255, entitled Development of Flame Retardant PV Module Encapsulants. While use of roof-mounted arrays has always been an attractive means of deploying PV, only within recent years have such building integrated concepts (BIPV) found renewed interest among module makers and end-users. Prior to building integrated and rooftop applications, flammability requirements for modules have not been a great industry concern. However, with growing interest in BIPV and the requirement for building code requirements for commercial and industrial structures, flammability issues have become a barrier to entry for many module constructions into this potentially huge domestic market for PV. The overall goal of the 3 phase PV BONUS two project is to develop and commercialize a line of fire retardant encapsulation materials to serve the emerging building integrated and building mounted PV market. The objectives of the Phase 1 effort are limited to concept development and business planning activities.

Galica, J.P.

1998-06-01T23:59:59.000Z

283

An investigation of urea decomposition and selective non-catalytic removal of nitric oxide with urea  

E-Print Network [OSTI]

]................................................................................... 22 17 The removal of NOx as a function of reactor temperature for seven levels of oxygen for 100 ppm carbon monoxide and a heated residence time of 2.11 secs. [42] ............................................................................. 23 18... The removal of NOx as a function of oxygen concentration for three levels of carbon monoxide (100, 600 and 900 ppm) for a reactor temperature of 1150 K and a heated residence time of 2.11 secs. [42]... 24 19 Influence of CO/NO ratio in the feed...

Park, Yong Hun

2004-09-30T23:59:59.000Z

284

Flow reactor experiments on the selective non-catalytic removal of nitrogen oxides  

E-Print Network [OSTI]

?CO, and H, O are initially present in exhaust stream [57]. .. . . . 42 Fig. 21 Fig. 22 Reaction path diagram for RAPRENOx process [63]. .. . Reduction of nitric oxide as a function of temperature, concentration of oxygen, carbon monoxide, and water... the influence of carbon monoxide [89]. . . . . . . . . 58 Fig. 28 Effect of residence time on the NOxOUT process as a function of temperature, NO(initial)=125ppm, 0-ratio of 4 [90]. .. . . . . . . . . . . . . . . 60 Fig. 29 Ammonia slip as a function...

Gentemann, Alexander M.G.

2001-01-01T23:59:59.000Z

285

Modeling of selective catalytic reduction (SCR) of nitric oxide with ammonia using four modern catalysts  

E-Print Network [OSTI]

In this work, the steady-state performance of zeolite-based Cu-ZSM-5, vanadium based honeycomb monolith catalysts (V), vanadium-titanium based pillared inter layered clay catalyst (V-Ti PLIC) and vanadium-titanium-tungsten-based honeycomb monolith...

Sharma, Giriraj

2005-11-01T23:59:59.000Z

286

Kinetic modeling of nitric oxide removal from exhaust gases by Selective Non-Catalytic Reduction  

E-Print Network [OSTI]

for increased pressure predict a wider temperature range at which significant nitric oxide can be removed and also in the case of RAPRENOx process the levels of N20 (a by-product in the case of the RAPRENOx process) are significantly lower. The accounting...

Chenanda, Cariappa Mudappa

2012-06-07T23:59:59.000Z

287

Experiments on the reduction of nitric oxide from exhaust gases by selective non-catalytic reactions  

E-Print Network [OSTI]

. The simulated exhaust gas contained varying amounts of N2, 02, H20, CO, and NO and the reactor conditions were varied with regard to temperature, residence time, and mixing. The results of these experiments show that the effect of oxygen concentration and NH3...

Narney, John Kenneth

1993-01-01T23:59:59.000Z

288

The catalytic oxidation of ethylene and butenes with air: total aldehyde production and selectivity  

E-Print Network [OSTI]

of startup, variation in ca. talyst composition, or by pretreat- ment of tl e catalyst, inadvertently, with a deactivating agent. Pretreate. ent of the catalyst with hydrogen gas be- fore a run proved to have an adverse effect on the forma- tion... for epoinp;, these investi- . gators concluded tliat hydroxylation is not an important factor in the oxidation of 2-butane under tne conditions considered. At 375 0 a slow reaction occurred and the r te of oxidation' increased at l. i, her tcr...

Burns, John Cunningham

1952-01-01T23:59:59.000Z

289

Growth of single-walled carbon nanotubes from size-selected catalytic metal particles.  

E-Print Network [OSTI]

that alcohols (e.g. methanol, ethanol) are a rather favorable carbon source that can synthesize large amounts correlation to that of the produced SWNTs [12]. However, since most of their nanoparticles were prepared for producing very high purity nanoparticles [13]. We have previously demonstrated the synthesis of size

Maruyama, Shigeo

290

Molybdenum and tungsen alkylidene species for catalytic Enantio-, Z-, and E-selective olefin metathesis reactions  

E-Print Network [OSTI]

CHAPTER1 A general introduction to olefin metathesis is given. Highlights include a detailed discussion of group VI imido alkylidene catalysts. CHAPTER 2 Several bispyrrolide species Mo(NAr)(CHCMe 2Ph)(pyr)2 (Ar = ...

Marinescu, Smaranda Constan?a

2011-01-01T23:59:59.000Z

291

Understanding ammonia selective catalytic reduction kinetics over Cu-SSZ-13  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layeredof2014National Nuclear23, 2014Cell Imaging. |from motion of

292

The Effect of Copper Loading on the Selective Catalytic Reduction of Nitric  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 and NbSe2Different Impacts of SO2 andOxide by Ammonia

293

Selective Catalytic Oxidation (SCO) of NH3 to N2 for Hot Exhaust Treatment  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage » SearchEnergyDepartment of Energy Moniz: WhatM-1at the High Temperature|

294

Impact of Biodiesel-Based Na on the Selective Catalytic Reduction (SCR) of  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeatMulti-Dimensionalthe U.S. Department-2023 Idaho4 AUDITof EnergyFuel

295

NH3-Selective Catalytic Reduction over Ag/Al2O3 Catalysts | Department of  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion | Department ofT ib l L d F S i DOEToward aInnovation |NEXT STEPS The next major

296

Protocol development for evaluation of commercial catalytic cracking catalysts  

SciTech Connect (OSTI)

A complete, new set of testing protocols has been developed for qualification of catalysts for Ashland's commercial catalytic cracking units. The objective of this test development is to identify new generations of improved cracking catalysts. Prior test protocols have classically utilized microactivity (MAT) testing of steamed virgin catalysts, while more advanced methods have utilized fixed fluid bed and/or circulating pilot units. Each of these techniques, however, have been limited by their correlation to commercial operations, weaknesses in metallation and preparation of pseudo-equilibrium catalysts, and mechanical constraints on the use of heavy, vacuum bottoms-containing feedstocks. These new protocols have been baselined, compared to commercial Ashland results on known catalytic cracking catalysts, and utilized to evaluate a range of potentially new catalyst samples.

Mitchell, M.M. Jr.; Moore, H.F. (Ashland Petroleum Co., KY (USA))

1988-09-01T23:59:59.000Z

297

Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway  

SciTech Connect (OSTI)

In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This technology pathway case investigates the catalytic conversion of solubilized carbohydrate streams to hydrocarbon biofuels, utilizing data from recent efforts within the National Advanced Biofuels Consortium (NABC) in collaboration with Virent, Inc.. Technical barriers and key research needs that should be pursued for the catalytic conversion of sugars pathway to be competitive with petroleum-derived gasoline, diesel and jet range hydrocarbon blendstocks have been identified.

Biddy, Mary J.; Jones, Susanne B.

2013-03-31T23:59:59.000Z

298

Catalytic destruction of groundwater contaminants in reactive extraction wells  

DOE Patents [OSTI]

A system for remediating groundwater contaminated with halogenated solvents, certain metals and other inorganic species based on catalytic reduction reactions within reactive well bores. The groundwater treatment uses dissolved hydrogen as a reducing agent in the presence of a metal catalyst, such a palladium, to reduce halogenated solvents (as well as other substituted organic compounds) to harmless species (e.g., ethane or methane) and immobilize certain metals to low valence states. The reactive wells function by removing water from a contaminated water-bearing zone, treating contaminants with a well bore using catalytic reduction, and then reinjecting the treated effluent into an adjacent water-bearing zone. This system offers the advantages of a compact design with a minimal surface footprint (surface facilities) and the destruction of a broad suite of contaminants without generating secondary waste streams.

McNab, Jr., Walt W. (Concord, CA); Reinhard, Martin (Stanford, CA)

2002-01-01T23:59:59.000Z

299

Catalytic Combustion for Ultra-Low NOx Hydrogen Turbines  

SciTech Connect (OSTI)

Precision Combustion, Inc., (PCI) in close collaboration with Solar Turbines, Incorporated, has developed and demonstrated a combustion system for hydrogen fueled turbines that reduces NOx to low single digit level while maintaining or improving current levels of efficiency and eliminating emissions of carbon dioxide. Full scale Rich Catalytic Hydrogen (RCH1) injector was developed and successfully tested at Solar Turbines, Incorporated high pressure test facility demonstrating low single digit NOx emissions for hydrogen fuel in the range of 2200F-2750F. This development work was based on initial subscale development for faster turnaround and reduced cost. Subscale testing provided promising results for 42% and 52% H2 with NOx emissions of less than 2 ppm with improved flame stability. In addition, catalytic reactor element testing for substrate oxidation, thermal cyclic injector testing to simulate start-stop operation in a gas turbine environment, and steady state 15 atm. operation testing were performed successfully. The testing demonstrated stable and robust catalytic element component life for gas turbine conditions. The benefit of the catalytic hydrogen combustor technology includes capability of delivering near-zero NOx without costly post-combustion controls and without requirement for added sulfur control. In addition, reduced acoustics increase gas turbine component life. These advantages advances Department of Energy (DOE’s) objectives for achievement of low single digit NOx emissions, improvement in efficiency vs. postcombustion controls, fuel flexibility, a significant net reduction in Integrated Gasification Combined Cycle (IGCC) system net capital and operating costs, and a route to commercialization across the power generation field from micro turbines to industrial and utility turbines.

Etemad, Shahrokh; Baird, Benjamin; Alavandi, Sandeep

2011-06-30T23:59:59.000Z

300

Hybrid lean premixing catalytic combustion system for gas turbines  

DOE Patents [OSTI]

A system and method of combusting a hydrocarbon fuel is disclosed. The system combines the accuracy and controllability of an air staging system with the ultra-low emissions achieved by catalytic combustion systems without the need for a pre-heater. The result is a system and method that is mechanically simple and offers ultra-low emissions over a wide range of power levels, fuel properties and ambient operating conditions.

Critchley, Ian L.

2003-12-09T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Two-stage Catalytic Reduction of NOx with Hydrocarbons  

SciTech Connect (OSTI)

A two-stage system for the catalytic reduction of NO from lean-burn natural gas reciprocating engine exhaust is investigated. Each of the two stages uses a distinct catalyst. The first stage is oxidation of NO to NO{sub 2} and the second stage is reduction of NO{sub 2} to N{sub 2} with a hydrocarbon. The central idea is that since NO{sub 2} is a more easily reduced species than NO, it should be better able to compete with oxygen for the combustion reaction of hydrocarbon, which is a challenge in lean conditions. Early work focused on demonstrating that the N{sub 2} yield obtained when NO{sub 2} was reduced was greater than when NO was reduced. NO{sub 2} reduction catalysts were designed and silver supported on alumina (Ag/Al{sub 2}O{sub 3}) was found to be quite active, able to achieve 95% N{sub 2} yield in 10% O{sub 2} using propane as the reducing agent. The design of a catalyst for NO oxidation was also investigated, and a Co/TiO{sub 2} catalyst prepared by sol-gel was shown to have high activity for the reaction, able to reach equilibrium conversion of 80% at 300 C at GHSV of 50,000h{sup -1}. After it was shown that NO{sub 2} could be more easily reduced to N{sub 2} than NO, the focus shifted on developing a catalyst that could use methane as the reducing agent. The Ag/Al{sub 2}O{sub 3} catalyst was tested and found to be inactive for NOx reduction with methane. Through iterative catalyst design, a palladium-based catalyst on a sulfated-zirconia support (Pd/SZ) was synthesized and shown to be able to selectively reduce NO{sub 2} in lean conditions using methane. Development of catalysts for the oxidation reaction also continued and higher activity, as well as stability in 10% water, was observed on a Co/ZrO{sub 2} catalyst, which reached equilibrium conversion of 94% at 250 C at the same GHSV. The Co/ZrO{sub 2} catalyst was also found to be extremely active for oxidation of CO, ethane, and propane, which could potential eliminate the need for any separate oxidation catalyst. At every stage, catalyst synthesis was guided by the insights gained through detailed characterization of the catalysts using many surface and bulk analysis techniques such as X-ray diffraction, X-ray photoelectron spectroscopy, Temperature-programmed Reduction, Temperature programmed Desorption, and Diffuse Reflectance InfraRed Fourier Transform Spectroscopy as well as steady state reaction experiments. Once active catalysts for each stage had been developed, a physical mixture of the two catalysts was tested for the reduction of NO with methane in lean conditions. These experiments using a mixture of the catalysts produced N2 yields as high as 90%. In the presence of 10% water, the catalyst mixture produced 75% N{sub 2} yield, without any optimization. The dual catalyst system developed has the potential to be implemented in lean-burn natural gas engines for reducing NOx in lean exhaust as well as eliminating CO and unburned hydrocarbons without any fuel penalty or any system modifications. If funding continues, future work will focus on improving the hydrothermal stability of the system to bring the technology closer to application.

Umit S. Ozkan; Erik M. Holmgreen; Matthew M. Yung; Jonathan Halter; Joel Hiltner

2005-12-21T23:59:59.000Z

302

Characterization of several plasters and one retarder for repository sealing mixtures. Final report  

SciTech Connect (OSTI)

Samples of plasters (i.e., calcium sulfate hemihydrate, CaSO4.1/2H/sup 2/0) from six sources and one plaster retarder from a different source were obtained and characterized by a combination of chemical and physical testing and by petrographic examination. The petrographic examination included x-ray diffraction, optical microscopy, differential thermal analysis, and scanning electron microscopy procedures. The intent of this work was twofold. One purpose was to determine if plaster per se could be used as an ingredient for cementitious mixtures intended for repository sealing applications, Previous experience had been with use of a proprietary admixture that contained plaster. The second purpose was to determine one or more methods of distinguishing between the alpha and beta forms of calcium sulfate hemihydrate. Keywords: nuclear wastes; plaster of paris; tables(data).

Buck, A.D.; Burkes, J.P.; Reinhold, R.E.

1985-09-01T23:59:59.000Z

303

Effect of Nitrogen Additives on Flame Retardant Action of Tributyl Phosphate: Phosphorus – Nitrogen Synergism  

SciTech Connect (OSTI)

The effect of nitrogen additives like urea, guanidine carbonate and melamine formaldehyde on the flame retardant efficacy of tributyl phosphate (TBP) has been investigated. From the LOI tests on treated cotton it is clear that the nitrogen additives have synergistic action. Estimation of activation energy of decomposition of treated cotton indicated that nitrogen additives enhance the thermal stability during the burning process. SEM pictures of chars formed after LOI test showed the formation of protective polymeric coating on the surface. The surface of chars formed were evaluated using FTIR-ATR and XPS analysis which showed that the coating was composed of Phosphorus-Nitrogen-Oxygen containing species. Formation of this coating during the burning process could lead to the synergistic interaction of phosphorus and nitrogen. Based on the experimental data we have further proposed several reaction mechanisms which could contribute to synergistic action and formation of protective coating on the surface of char.

Gaan, Sabyasachi; Sun, Gang; Hutches, Katherine; Engelhard, Mark H.

2008-01-01T23:59:59.000Z

304

Kinetic study on the catalytic performance of Rh/TiO/sub 2/ reduced at different temperatures in the CO-H/sub 2/ reaction  

SciTech Connect (OSTI)

Catalytic CO-H/sub 2/ reaction on Rh/TiO/sub 2/ reduced at 200, 400, and 500/sup 0/C (Cat-200, -400, -500) for 2 h was kinetically studied at 250/sup 0/C using a circulating reactor and Fourier transform-infrared (FT-IR) spectroscopy to determine how Cat-400 exhibited the highest activity. The rate equation distinguished the best catalyst with zero and first orders in CO and H/sub 2/, respectively, from other catalysts with negative order in CO. The adsorption ability of the catalyst at 200/sup 0/C was comparable to that of Cat-200, and two to three times larger than that of Cat-500, although the ability of Cat-200 was much larger at room temperature. Carbon monoxide adsorbed on the catalysts reversibly as well as irreversibly. IR spectroscopy revealed that the major form of irreversibly adsorbed CO was linear on Cat-200, whereas similar amounts of linear and bridge forms were observed on Cat-400 and Cat-500. These latter forms were highly reactive against hydrogen molecules when no carbon monoxide was present in the gas phase. Based on these results, the highest activity of Cat-400 is ascribed to rhodium metal modified by properly reduced TiO/sub 2/ to show the appropriate adsorption ability of carbon monoxide which least retards the activation of hydrogen according to first-order kinetics. Typical strong metal-support interaction decreases the catalytic activity by decreasing the active sites and strengthening the CO adsorption too much.

Fujitsu, H.; Ikeyama, N.; Mochida, I.

1986-08-01T23:59:59.000Z

305

Electroless preparation and characterization of Ni-B nanoparticles supported on multi-walled carbon nanotubes and their catalytic activity towards hydrogenation of styrene  

SciTech Connect (OSTI)

Graphical abstract: The MWCNT/Ni-B catalyst has been successfully prepared by an electroless deposition process. The Ni-B nanoparticles on the supporter are amorphous and are well-distributed. The catalytic conversion towards hydrogenation of styrene shows excellent catalytic activity of the obtained materials. Highlights: Black-Right-Pointing-Pointer A two-step treatment of MWCNTs enabled the homogeneous growth of Ni-B nanoparticles. Black-Right-Pointing-Pointer Ni-B nanoparticles were amorphous with an average size of 60 nm. Black-Right-Pointing-Pointer There were electron transfer between Ni and B. Black-Right-Pointing-Pointer The catalyst had excellent catalytic activity towards hydrogenation of styrene. -- Abstract: Nickel-boron (Ni-B) nanoparticles supported on multi-walled carbon nanotubes (MWCNTs) were successfully synthesized through an electroless deposition process using the plating bath with sodium borohydride as a reducing agent. The structural and morphological analyses using field-emission scanning electron microscopy, X-ray diffractometry and high-resolution transmission electron microscopy have shown that the Ni-B nanoparticles deposited on the sidewalls of MWCNTs are fine spheres comprised of amorphous structure with the morphologically unique fine-structure like flowers, and homogenously dispersed with a narrow particle size distribution centered at around 60 nm diameter. The catalytic activity of MWCNT/Ni-B nanoparticles was evaluated with respect to hydrogenation of styrene. The hydrogenation catalyzed by MWCNT-supported Ni-B nanoparticles has been found to make styrene selectively converted into ethylbenzene. The highest conversion reaches 99.8% under proper reaction conditions, which demonstrates the high catalytic activity of MWCNT/Ni-B nanoparticles.

Liu, Zheng; Li, Zhilin [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China) [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Institute of Carbon Fibers and Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Wang, Feng, E-mail: wangf@mail.buct.edu.cn [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China) [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Institute of Carbon Fibers and Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Liu, Jingjun; Ji, Jing [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China) [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Institute of Carbon Fibers and Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Park, Ki Chul [Institute of Carbon Science and Technology (ICST), Shinshu University, 4-17-1 Wakasato, Nagano-shi, Nagano 380-8553 (Japan)] [Institute of Carbon Science and Technology (ICST), Shinshu University, 4-17-1 Wakasato, Nagano-shi, Nagano 380-8553 (Japan); Endo, Morinobu [Department of Electrical and Electronic Engineering, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano-shi, Nagano 380-8553 (Japan)] [Department of Electrical and Electronic Engineering, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano-shi, Nagano 380-8553 (Japan)

2012-02-15T23:59:59.000Z

306

Instrument for Measuring the Earth's Time-Retarded Transverse Gravitational Vector Potential  

E-Print Network [OSTI]

Here within the basic design for a ground-based instrument for measuring the magnitude of the Earth's time-retarded transverse gravitational vector potential is described. The formula for the Earth's transverse vector potential is derived from the known formula for the neoclassical time-retarded transverse gravitational field (arXiv:0904.0383v2 [physics.gen-ph] 25May2010). The device senses the relativistic shift in the frequency of laser-diode oscillators set into circular motion at the tips of a two-arm rotor. The instrument employs fiber optics and a digital electronic interferometer/spectrometer to measure the effect of the relativistic time dilation on the frequency-modulated (FM) harmonic amplitudes in the beat signals between the tip-diodes and a stationary reference diode. The FM amplitudes depend on the orientation of the rotor. For the vertical-east-west orientation with a rotor frequency of 73.9 Hz, the predicted FM amplitudes for overtones at 148 Hz, 222 Hz, and 296 Hz are respectively 7x10^-10 Hz, 4x10^-11 Hz, and 9x10^-11 Hz. The overtones in the beat signals can be amplified and observed with a tunable FM digital audio amplifier. The measured values for the harmonics of the vector potential can be determined by back-calculating what the amplitudes must have been at the input to the amplifier. The instrument can be used to establish the speed of the Earth's gravitational field and to study the structure of the Earth's mantle and outer core.

J. C. Hafele

2010-09-20T23:59:59.000Z

307

Moisture effects in low-slope roofs: Drying rates after water addition with various vapor retarders  

SciTech Connect (OSTI)

Tests have been conducted in the Large Scale Climate Simulator (LSCS) of the US. Building Envelope Research Center at the Oak Ridge National Laboratory (ORNL) to investigate downward drying rates of various unvented, low-slope roof systems. A secondary objective was to study heat flow patterns so as to understand how to control latent heat effects on impermeable heat flux transducers. Nine test sections were tested simultaneously. The sections had a p deck above fibrous-glass insulation and were examples of cold-deck systems. These five sections had various vapor retarder systems on a gypsum board ceiling below the insulation. The other four sections had a lightweight insulating concrete deck below expanded polystyrene insulation and the same vapor retarder systems, and were examples of warm-deck systems. The cold-deck systems had materials that were relatively permeable to water vapor, while the materials in the warm-deck systems were less permeable. All test sections were topped by an impermeable roofing membrane. The test sections were instrumented with thermocouples between all layers and with small heat flux transducers at the bottom and top of the fibrous-glass insulation and in the middle of the expanded polystyrene insulation. Two different kinds of moisture probes were used to qualitatively monitor the movement of the moisture. The heat flux measurements showed that heat conduction dominates the system using impermeable insulation materials, with only a slight increase due to increased thermal conductivity of wet expanded polystyrene. There was significant transfer of latent heat in the test sections with permeable insulation, causing the peak heat fluxes to increase by as much as a factor of two. With temperatures imposed that are typical of summer days, latent heat transfer associated with condensation and evaporation of moisture in the test sections was measured to be as important as the heat transfer by conduction.

Pedersen, C.R. [Technical Univ. of Denmark, Lyngby (Denmark); Petrie, T.W. [Marquette Univ., Milwaukee, WI (United States). Dept. of Mechanical Engineering; Courville, G.E.; Desjarlais, A.O.; Childs, P.W.; Wilkes, K.E. [Oak Ridge National Lab., TN (United States)

1992-10-01T23:59:59.000Z

308

Body burdens of brominated flame retardants and other persistent organo-halogenated compounds and their descriptors in US girls  

SciTech Connect (OSTI)

Background: Levels of brominated flame retardants are increasing in US populations, yet little data are available on body burdens of these and other persistent hormonally active agents (HAAs) in school-aged children. Exposures to such chemicals may affect a number of health outcomes related to development and reproductive function. Objective: Determine the distribution of biomarkers of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and organo-chlorinated pesticides (OCPs), such as DDT/DDE, in children, and their variation by key descriptor variables. Methods: Ethnically diverse cohorts of girls 6-8 y old at baseline are being followed for growth and pubertal development in a multi-site, longitudinal study. Nearly 600 serum samples from the California and Ohio sites were analyzed for lipids, 35 PCB congeners, 11 PBDE congeners, and 9 OCPs. The biomarker distributions were examined and geometric means compared for selected analytes across categories of age, race, site, body mass index (BMI), parental education, maternal age at delivery, and breast feeding in adjusted models. Results: Six PBDE congeners were detected among greater than 70% of samples, with BDE-47 having the highest concentration (median 42.2, range 4.9-855 ng/g lipid). Girls in California had adjusted geometric mean (GM) PBDE levels significantly higher than girls in Ohio. Furthermore, Blacks had significantly higher adjusted GMs of all six PBDE congeners than Whites, and Hispanics had intermediate values. GMs tended to be lower among more obese girls, while other variables were not strongly associated. In contrast, GMs of the six PCB congeners most frequently detected were significantly lower among Blacks and Hispanics than Whites. PCBs and the three pesticides most frequently detected were also consistently lower among girls with high BMI, who were not breast-fed, whose mothers were younger, or whose care-givers (usually parents) were less educated. Girls in California had higher GMs than in Ohio for the pesticides and most PCB congeners, but the opposite for CB-99 and -118. Conclusions: Several of these potential HAAs were detected in nearly all of these young girls, some at relatively high levels, with variation by geographic location and other demographic factors that may reflect exposure pathways. The higher PBDE levels in California likely reflect differences in fire regulation and safety codes, with potential policy implications.

Windham, Gayle C., E-mail: gayle.windham@cdph.ca.gov [CA Department of Public Health, DEODC, 850 Marina Bay Pkwy, Bldg. P, Richmond, CA 94804 (United States); Pinney, Susan M. [University of Cincinnati College of Medicine, Cincinnati, OH 45267 (United States)] [University of Cincinnati College of Medicine, Cincinnati, OH 45267 (United States); Sjodin, Andreas [Centers for Disease Control and Prevention, Atlanta, GA 30341 (United States)] [Centers for Disease Control and Prevention, Atlanta, GA 30341 (United States); Lum, Raymond [Impact Assessment Inc., San Diego, CA (United States)] [Impact Assessment Inc., San Diego, CA (United States); Jones, Richard S.; Needham, Larry L. [Centers for Disease Control and Prevention, Atlanta, GA 30341 (United States)] [Centers for Disease Control and Prevention, Atlanta, GA 30341 (United States); Biro, Frank M. [University of Cincinnati College of Medicine, Cincinnati, OH 45267 (United States)] [University of Cincinnati College of Medicine, Cincinnati, OH 45267 (United States); Hiatt, Robert A. [University of California Medical School, San Francisco, CA (United States)] [University of California Medical School, San Francisco, CA (United States); Kushi, Lawrence H. [Kaiser Permanente Northern California, Oakland, CA 94612 (United States)] [Kaiser Permanente Northern California, Oakland, CA 94612 (United States)

2010-04-15T23:59:59.000Z

309

Catalytic microwave torrefaction and pyrolysis of Douglas fir pellet to improve biofuel quality .  

E-Print Network [OSTI]

??The aims of this dissertation were to understand the effects of torrefaction as pretreatment on biomass pyrolysis and catalytic pyrolysis for improving biofuel quality, and… (more)

[No author

2012-01-01T23:59:59.000Z

310

New sub-family of lysozyme-like proteins shows no catalytic activity...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

modest sequence similarity to phage-like lysozyme (N-acetylmuramidase) but appears to lack essential catalytic residues that are strictly conserved in all lysozymes. Close...

311

E-Print Network 3.0 - auto-catalytic electroless plating Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

electroless plating Page: << < 1 2 3 4 5 > >> 1 Preparation of highly dispersed PEM fuel cell catalysts using electroless deposition methods Summary: (ED). ED is a catalytic...

312

Solid state oxygen anion and electron mediating membrane and catalytic membrane reactors containing them  

DOE Patents [OSTI]

A process for production of synthesis gas employing a catalytic membrane reactor wherein the membrane comprises a mixed metal oxide material.

Schwartz, Michael (Boulder, CO); White, James H. (Boulder, CO); Sammells, Anthony F. (Boulder, CO)

2001-01-01T23:59:59.000Z

313

Recent Advances in Catalytic Conversion of Ethanol to Chemicals  

SciTech Connect (OSTI)

With increased availability and decreased cost, ethanol is potentially a promising platform molecule for the production of a variety of value-added chemicals. In this review, we provide a detailed summary of recent advances in catalytic conversion of ethanol to a wide range of chemicals and fuels. We particularly focus on catalyst advances and fundamental understanding of reaction mechanisms involved in ethanol steam reforming (ESR) to produce hydrogen, ethanol conversion to hydrocarbons ranging from light olefins to longer chain alkenes/alkanes and aromatics, and ethanol conversion to other oxygenates including 1-butanol, acetaldehyde, acetone, diethyl ether, and ethyl acetate.

Sun, Junming; Wang, Yong

2014-04-30T23:59:59.000Z

314

Advanced product recovery: Direct catalytic reduction of sulfur dioxide to elemental sulfur. Third quarterly technical progress report  

SciTech Connect (OSTI)

More than 170 wet scrubber systems applied to 72,000 MW of US, coal-fired, utility boilers are in operation or under construction. In these systems, the sulfur dioxide removed form the boiler flue gas is permanently bound to a sorbent material, such as lime or limestone. The sulfated sorbent must be disposed of as a waste product or, in some cases, sold as a byproduct (e.g. gypsum). The use of regenerable sorbent technologies has the potential to reduce or eliminate solid waste production, transportation and disposal. Arthur D. Little, Inc., together with its industry and commercialization advisor, Engelhard Corporation, and its university partner, Tufts, plans to develop and scale-up an advanced, byproduct recovery technology that is a direct, catalytic process for reducing sulfur dioxide to elemental sulfur. The principal objective of the Phase 1 program is to identify and evaluate the performance of a catalyst which is robust and flexible with regard to choice of reducing gas. In order to achieve this goal, they have planned a structured program including: market/process/cost/evaluation; lab-scale catalyst preparation/optimization studies; lab-scale, bulk/supported catalyst kinetic studies; bench-scale catalyst/process studies; and utility review. This catalytic process reduces SO{sub 2} over a fluorite-type oxide (such as ceria and zirconia). The catalytic activity can be significantly promoted by active transition metals, such as copper. This type of mixed metal oxide catalyst has stable activity, high selectivity for sulfur production, and is resistant to water and carbon dioxide poisoning.

NONE

1996-07-01T23:59:59.000Z

315

Copper- and silver-zirconia aerogels: Preparation, structural properties and catalytic behavior in methanol synthesis from carbon dioxide  

SciTech Connect (OSTI)

Copper- and silver-zirconia aerogels containing 10 at% IB metal were prepared from tetra-n-butoxy zirconium(IV) and IB metal acetates using the solution sol-gel method and ensuring high-temperature (HT) and low-temperature (LT) supercritical drying, respectively. The influence of preparation parameters and calcination on the structural and catalytic properties of the aerogels for the synthesis of methanol from carbon dioxide and hydrogen was investigated. After calcination in air at 573 K, the catalysts had BET surface areas in the range of 100--143 m{sup 2}/g (Cu/ZrO{sub 2}) and 77--125 m{sup 2}/g (Ag/ZrO{sub 2}), respectively. Due to the reductive alcoholic atmosphere during high-temperature supercritical drying, metallic copper and silver existed in all raw HT-aerogels. The mean size of the copper crystallites wa/s 30 nm. The silver crystallite size for the HT-aerogel prepared with nitric acid was 10 nm, whereas for samples prepared with acetic acid it was 5--7 nm. Calcination in air at 573 K led to the formation of highly dispersed amorphous copper oxide and silver. Comparing the catalytic behavior of the calcined copper-zirconia aerogels with corresponding xerogels prepared by coprecipitation revealed highest activity for the LT-aerogel, whereas the HT-aerogels were least active. In contrast, similar catalytic behavior was observed for the differently dried silver-zirconia samples. Generally, CO{sub 2}-conversion of the copper-zirconia samples. Generally, CO{sub 2}-conversion of the copper-zirconia aerogels was markedly higher than that of the corresponding silver-zirconia aerogels, whereas methanol selectivity was similar.

Koeppel, R.A.; Stoecker, C.; Baiker, A. [Swiss Federal Inst. of Technology, Zuerich (Switzerland). Lab. of Technical Chemistry] [Swiss Federal Inst. of Technology, Zuerich (Switzerland). Lab. of Technical Chemistry

1998-10-25T23:59:59.000Z

316

Advanced byproduct recovery: Direct catalytic reduction of sulfur dioxide to elemental sulfur. Quarterly report, April 1--June 30, 1997  

SciTech Connect (OSTI)

The team of Arthur D. Little, Tufts University and Engelhard Corporation are conducting Phase 1 of a four and a half year, two-phase effort to develop and scale-up an advanced byproduct recovery technology that is a direct, single-stage, catalytic process for converting sulfur dioxide to elemental sulfur. This catalytic process reduces SO{sub 2} over a fluorite-type oxide (such as ceria and zirconia). The catalytic activity can be significantly promoted by active transition metals, such as copper. More than 95% elemental sulfur yield, corresponding to almost complete sulfur dioxide conversion, was obtained over a Cu-Ce-O oxide catalyst as part of an on-going DOE-sponsored, University Coal Research Program. This type of mixed metal oxide catalyst has stable activity, high selectivity for sulfur production, and is resistant to water and carbon dioxide poisoning. Tests with CO and CH{sub 4} reducing gases indicate that the catalyst has the potential for flexibility with regard to the composition of the reducing gas, making it attractive for utility use. The performance of the catalyst is consistently good over a range of SO{sub 2} inlet concentration (0.1 to 10%) indicating its flexibility in treating SO{sub 2} tail gases as well as high concentration streams. The principal objective of the Phase 1 program is to identify and evaluate the performance of a catalyst which is robust and flexible with regard to choice of reducing gas. In order to achieve this goal, the authors have planned a structured program including: Market/process/cost/evaluation; Lab-scale catalyst preparation/optimization studies; Lab-scale, bulk/supported catalyst kinetic studies; Bench-scale catalyst/process studies; and Utility review. Progress is reported from all three organizations.

NONE

1997-12-31T23:59:59.000Z

317

Local investigation of the electronic properties of size-selected Au nanoparticles by scanning tunneling spectroscopy  

E-Print Network [OSTI]

. Transition metal carbides such as TiC have shown great potential as catalytic supports due to their hardness the electronic, optical, magnetic, and chemical properties displayed by small metallic nanopar- ticles have been- tronic properties of size-selected Au nanoparticles supported on ultrathin titanium carbide films

Kik, Pieter

318

Catalytic ionic hydrogenation of ketones using tungsten or molybdenum organometallic species  

DOE Patents [OSTI]

The present invention is a process for the catalytic hydrogenation of ketones and aldehydes to alcohols at low temperatures and pressures using organometallic molybdenum and tungsten complexes. The functional group is selected from groups represented by the formulas R(C.dbd.O)R' and R(C.dbd.O)H, wherein R and R' are selected from hydrogen or any alkyl or aryl group. The active catalyst for the process has the form: [CpM(CO).sub.2 (PR*.sub.3) L].sup.+ A.sup.-, where Cp=.eta..sup.5 -R.sup..tangle-solidup..sub.m C.sub.5 H.sub.5-m and R.sup..tangle-solidup. represents an alkyl group or a halogen (F, Cl, Br, I) or R.sup..tangle-solidup. =OR' (where R'=H, an alkyl group or an aryl group) or R.sup..tangle-solidup. =CO.sub.2 R' (where R'=H, an alkyl group or an aryl group) and m=0 to 5; M represents a molybdenum atom or a tungsten atom; R*.sub.3 represents three hydrocarbon groups selected from a cyclohexyl group (C.sub.6 H.sub.11), a methyl group (CH.sub.3), and a phenyl group (C.sub.6 H.sub.5) and all three R* groups can be the same or different or two of the three groups can be the same; L represents a ligand; and A.sup.- represents an anion. In another embodiment, one, two or three of the R* groups can be an OR*.

Voges, Mark (Leverkusen, DE); Bullock, R. Morris (Wading River, NY)

2000-01-01T23:59:59.000Z

319

Catalytic ionic hydrogenation of ketones using tungsten or molybdenum catalysts with increased lifetimes  

DOE Patents [OSTI]

The present invention is a process for the catalytic hydrogenation of ketones and aldehydes to alcohols at low temperatures and pressures using organometallic molybdenum and tungsten complexes and the catalyst used in the process. The reactants include a functional group which is selected from groups represented by the formulas R*(C.dbd.O)R' and R*(C.dbd.O)H, wherein R* and R' are selected from hydrogen or any alkyl or aryl group. The process includes reacting the organic compound in the presence of hydrogen and a catalyst to form a reaction mixture. The catalyst is prepared by reacting Ph.sub.3 C.sup.+ A.sup.- with a metal hydride. A.sup.- represents an anion and can be BF.sub.4.sup.-, PF.sub.6.sup.-, CF.sub.3 SO.sub.3.sup.- or Bar'.sub.4.sup.-, wherein Ar'=3,5-bis(trifluoromethyl)phenyl. The metal hydride is represented by the formula: HM(CO).sub.2 [.eta..sup.5 :.eta..sup.1 --C.sub.5 H.sub.4 (XH.sub.2).sub.n PR.sub.2 ] wherein M represents a molybdenum (Mo) atom or a tungsten (W) atom; X is a carbon atom, a silicon atom or a combination of carbon (C) and silicon (Si) atoms; n is any positive integer; R represents two hydrocarbon groups selected from H, an aryl group and an alkyl group, wherein both R groups can be the same or different. The metal hydride is reacted with Ph.sub.3 C.sup.+ A.sup.- either before reacting with the organic compound or in the reaction mixture.

Bullock, R. Morris; Kimmich, Barbara F.; Fagan, Paul J.; Hauptman, Elisabeth

2003-09-02T23:59:59.000Z

320

Trends in Selective Hydrogen Peroxide Production on Transition Metal Surfaces from First Principles  

SciTech Connect (OSTI)

We present a comprehensive, Density Functional Theory-based analysis of the direct synthesis of hydrogen peroxide, H2O2, on twelve transition metal surfaces. We determine the full thermodynamics and selected kinetics of the reaction network on these metals, and we analyze these energetics with simple, microkinetically motivated rate theories to assess the activity and selectivity of hydrogen peroxide production on the surfaces of interest. By further exploiting Brønsted-Evans-Polanyi relationships and scaling relationships between the binding energies of different adsorbates, we express the results in the form of a two dimensional contour volcano plot, with the activity and selectivity being determined as functions of two independent descriptors, the atomic hydrogen and oxygen adsorption free energies. We identify both a region of maximum predicted catalytic activity, which is near Pt and Pd in descriptor space, and a region of selective hydrogen peroxide production, which includes Au. The optimal catalysts represent a compromise between activity and selectivity and are predicted to fall approximately between Au and Pd in descriptor space, providing a compact explanation for the experimentally known performance of Au-Pd alloys for hydrogen peroxide synthesis, and suggesting a target for future computational screening efforts to identify improved direct hydrogen peroxide synthesis catalysts. Related methods of combining activity and selectivity analysis into a single volcano plot may be applicable to, and useful for, other aqueous phase heterogeneous catalytic reactions where selectivity is a key catalytic criterion.

Rankin, Rees B.; Greeley, Jeffrey P.

2012-10-19T23:59:59.000Z

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321

Catalytic ignition of fuel/oxygen/nitrogen mixtures over platinum  

SciTech Connect (OSTI)

Ignition of fuel/oxygen/nitrogen mixtures over platinum wire is experimentally studied by using microcalorimetry and by restricting the flow to the low Reynolds number range so that axisymmetry prevails. The fuels studied are propane, butane, propylene, ethylene, carbon monoxide, and hydrogen. Parameters investigated include flow velocity, fuel type and concentration, and oxygen concentration. The catalytic ignition temperatures of the various fuels are accurately determined over extensive ranges of fuel/oxygen/nitrogen concentrations. Results show two distinctly opposite ignition trends depending on the nature of the fuel. That is, the ignition temperature of lean propane/air and butane/air mixtures decreases as their fuel concentration is increased, while the reverse trend is observed for lean mixtures of propylene, ethylene, carbon monoxide, and hydrogen with air. Furthermore, the ignition of propane depends primarily on fuel concentration, while the ignition of carbon monoxide depends on fuel and oxygen concentrations to a comparable extent. These results are explained on the basis of hierarchical surface adsorption strengths of the different reactants in effecting catalytic ignition. Additional phenomena of interest are observed and discussed.

Cho, P.; Law, C.K.

1986-11-01T23:59:59.000Z

322

Catalytic combustor for integrated gasification combined cycle power plant  

DOE Patents [OSTI]

A gasification power plant 10 includes a compressor 32 producing a compressed air flow 36, an air separation unit 22 producing a nitrogen flow 44, a gasifier 14 producing a primary fuel flow 28 and a secondary fuel source 60 providing a secondary fuel flow 62 The plant also includes a catalytic combustor 12 combining the nitrogen flow and a combustor portion 38 of the compressed air flow to form a diluted air flow 39 and combining at least one of the primary fuel flow and secondary fuel flow and a mixer portion 78 of the diluted air flow to produce a combustible mixture 80. A catalytic element 64 of the combustor 12 separately receives the combustible mixture and a backside cooling portion 84 of the diluted air flow and allows the mixture and the heated flow to produce a hot combustion gas 46 provided to a turbine 48. When fueled with the secondary fuel flow, nitrogen is not combined with the combustor portion.

Bachovchin, Dennis M. (Mauldin, SC); Lippert, Thomas E. (Murrysville, PA)

2008-12-16T23:59:59.000Z

323

An atomic-scale analysis of catalytically-assisted chemical vapor deposition of carbon nanotubes  

E-Print Network [OSTI]

An atomic-scale analysis of catalytically-assisted chemical vapor deposition of carbon nanotubes M Growth of carbon nanotubes during transition-metal particles catalytically-assisted thermal decomposition of various nanotube surface and edge reactions (e.g. adsorption of hydrocarbons and hydrogen onto the surface

Grujicic, Mica

324

Control of Natural Gas Catalytic Partial Oxidation for Hydrogen Generation in Fuel Cell Applications1  

E-Print Network [OSTI]

Control of Natural Gas Catalytic Partial Oxidation for Hydrogen Generation in Fuel Cell Ghosh3 , Huei Peng2 Abstract A fuel processor that reforms natural gas to hydrogen-rich mixture to feed of the hydrogen in the fuel processor is based on catalytic partial oxidation of the methane in the natural gas

Peng, Huei

325

Burning Velocities in Catalytically Assisted Self-Propagating High-Temperature Combustion Synthesis Systems  

E-Print Network [OSTI]

Burning Velocities in Catalytically Assisted Self-Propagating High-Temperature Combustion Synthesis of catalytically assisted self-propagating high-temperature synthesis (SHS) of the tantalum/carbon material system. © 2001 by The Combustion Institute INTRODUCTION Self-propagating high-temperature combustion synthesis

Wooldridge, Margaret S.

326

Scaling behavior of optimally structured catalytic microfluidic reactors Fridolin Okkels and Henrik Bruus  

E-Print Network [OSTI]

Scaling behavior of optimally structured catalytic microfluidic reactors Fridolin Okkels and Henrik of catalytic microfluidic reactors we show that, when optimally structured, these reactors share underlying the reactor using a high-level implementation of topology optimization. DOI: 10.1103/PhysRevE.75.016301 PACS

327

Micro Catalytic Combustor with Pd/Nano-porous Alumina for High-Temperature Application  

E-Print Network [OSTI]

Micro Catalytic Combustor with Pd/Nano-porous Alumina for High-Temperature Application Takashi: A micro-scale catalytic combustor using high-precision ceramic tape-casting technology has been developed surface reaction of butane. In combustion experiments with a prototype combustor, the wall temperature

Kasagi, Nobuhide

328

Non-uniform Heat Generation in Micro Catalytic Combustor Takashi Okamasa*, Yuji Suzuki, and Nobuhide Kasagi  

E-Print Network [OSTI]

Non-uniform Heat Generation in Micro Catalytic Combustor Takashi Okamasa*, Yuji Suzuki@thtlab.t.u-tokyo.ac.jp Abstract We developed a micro catalytic combustor using high-precision ceramic tape-casting technology and nano-porous alumina catalyst layer. It is found that failure of the ceramic combustor occurs due

Kasagi, Nobuhide

329

The Catalytic Chemistry of HCN+NO over Na- and Ba-Y, FAU: An...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The Catalytic Chemistry of HCN+NO over Na- and Ba-Y, FAU: An In Situ FTIR and TPDTPR Study. The Catalytic Chemistry of HCN+NO over Na- and Ba-Y, FAU: An In Situ FTIR and TPDTPR...

330

MEMS-based fuel cells with integrated catalytic fuel processor and method thereof  

DOE Patents [OSTI]

Described herein is a means to incorporate catalytic materials into the fuel flow field structures of MEMS-based fuel cells, which enable catalytic reforming of a hydrocarbon based fuel, such as methane, methanol, or butane. Methods of fabrication are also disclosed.

Jankowski, Alan F. (Livermore, CA); Morse, Jeffrey D. (Martinez, CA); Upadhye, Ravindra S. (Pleasanton, CA); Havstad, Mark A. (Davis, CA)

2011-08-09T23:59:59.000Z

331

An analysis of the performance of black and white retardates on the Wechsler Intelligence Scale for children  

E-Print Network [OSTI]

) Catherine Phillips Thompson, B. A. , Texas Christian University Directed by: Dr. Walter A. Varvel The subtest scores of 234 black and 141 white retarded children were submitted to factor analyses for race and age. In both cases, three factors emerged...: Verbal, Perceptual Organization, and Stimulus Trace. In addition, when the data were factored on the basis of age classification, a fourth factor emerged for children above the age of nine years. It was proposed that for older children, the stimulus...

Thompson, Catherine Phillips

1972-01-01T23:59:59.000Z

332

Incorporation of catalytic dehydrogenation into Fischer-Tropsch synthesis to lower carbon dioxide emissions  

DOE Patents [OSTI]

A method for producing liquid fuels includes the steps of gasifying a starting material selected from a group consisting of coal, biomass, carbon nanotubes and mixtures thereof to produce a syngas, subjecting that syngas to Fischer-Tropsch synthesis (FTS) to produce a hyrdrocarbon product stream, separating that hydrocarbon product stream into C1-C4 hydrocarbons and C5+ hydrocarbons to be used as liquid fuels and subjecting the C1-C4 hydrocarbons to catalytic dehydrogenation (CDH) to produce hydrogen and carbon nanotubes. The hydrogen produced by CDH is recycled to be mixed with the syngas incident to the FTS reactor in order to raise the hydrogen to carbon monoxide ratio of the syngas to values of 2 or higher, which is required to produce liquid hydrocarbon fuels. This is accomplished with little or no production of carbon dioxide, a greenhouse gas. The carbon is captured in the form of a potentially valuable by-product, multi-walled carbon nanotubes (MWNT), while huge emissions of carbon dioxide are avoided and very large quantities of water employed for the water-gas shift in traditional FTS systems are saved.

Huffman, Gerald P

2012-09-18T23:59:59.000Z

333

Immobilization of vanadia deposited on catalytic materials during carbo-metallic oil conversion  

SciTech Connect (OSTI)

This patent describes a process for the cracking of a hydrocarbon oil feed having a significant content of at least 0.1 ppm vanadium to lighter oil products. The process consists of contacting the feed under conversion conditions in a conversion zone with a catalyst containing a precipitated metal additive to immobilize vanadium compounds by forming compounds therewith that have melting points above temperatures found in regenerating a coked catalyst; and having catalytic cracking characteristics, coke and vanadium being deposited on the catalyst by the contact; regenerating the coked catalyst in the presence of an oxygen containing gas at a temperature sufficient to remove at least some of the coke, and, recycling the regenerated catalyst to the conversion zone for contact with fresh feed; the metal additive being present on the catalyst in an amount sufficient to immobilize at least a portion of the vanadium compound in the presence of the oxygen containing gas at the catalyst regeneration temperature; wherein the metal additive to immobilize vanadium compounds deposited on the catalyst is selected from the group consisting of Sr, Sc, Y, Nb, and Ta elements, and an element in the actinide series, or a combination of two or more of the elements.

Beck, H.W.; Carruthers, J.D.; Cornelius, E.B.; Hettinger, Jr., W.P.; Kovach, S.M.; Palmer, J.L.; Zandona, O.J.

1988-06-14T23:59:59.000Z

334

Catalytic hydrogenation and gas permeation properties of metal-containing poly(phenylene oxide) and polysulfone  

SciTech Connect (OSTI)

Metal-containing polymers, PPL-DPP-Pd, PPO-CPA-Pd, PSF-DPP-Pd, PSF-CPA-Pd (PDD = diphenylphosphinyl, CPA = o-carboxy phenyl amino), PPO-M (M = Pd,Cu,Co,Ni), and PSF-Pd, were prepared by incorporating metal chloride with either modified or unmodified poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) and polysulfone (PSF). The Pd-containing polymers exhibit catalytic activity in the hydrogenation of cyclopentadiene under mild conditions both in alcohol solution and in the gas phase. The selectivity in the hydrogenation of diene to monoene in the gas phase can be controlled by adjusting the hydrogen partial pressure. The metal-containing polymers, PPL-M and PSF-Pd, can be cast easily into the membranes. The H[sub 2]/N[sub 2] permselectivity for PPO-M is higher than that for unmodified PPO, whereas the permeability of H[sub 2] changes slightly. The H[sub 2] permeability and H[sub 2]/N[sub 2] permselectivity for the PPO-Pd membrane are up to 67.5 barrers and 135, respectively.

Hanrong Gao; Yun Xu; Shijian Liao; Ren Liu; Daorong Yu (Chinese Academy of Sciences, Dalian (China). Dalian Inst. of Chemical Physics)

1993-11-10T23:59:59.000Z

335

Catalytic conversion of light alkanes - phase V. Topical report, February 1993--October 1994  

SciTech Connect (OSTI)

We have made excellent progress toward a practical route from field butanes to MTBE, the oxygenate of choice for high-octane, clean-burning, environmentally acceptable reformulated gasoline. We have evaluated two proprietary process possibilities with a potential commercial partner and have conducted a joint catalyst evaluation program. The first of the two potential processes considered during the past quarter utilizes a two-step route from isobutane to tert-butyl alcohol, TBA. Not only is TBA an intermediate for MTBE production but is equally applicable for ETBE-an oxygenate which utilizes renewable ethanol in its` manufacture. In the two-step process, isobutane is oxidized in a non-catalytic reaction to a roughly equal mixture of TBA and tert-butyl hydroperoxide. TBHP, eq. 1. We have developed an inexpensive new catalyst system based on an electron-deficient macrocyclic metal complex that selectively converts TBHP to TBA, eq. 2, and meets or exceeds all of the process criteria that we have set.

NONE

1998-12-31T23:59:59.000Z

336

Advanced byproduct recovery: Direct catalytic reduction of SO{sub 2} to elemental sulfur. First quarterly technical progress report, [October--December 1995  

SciTech Connect (OSTI)

The team of Arthur D. Little, Tufts University and Engelhard Corporation will be conducting Phase I of a four and a half year, two-phase effort to develop and scale-up an advanced byproduct recovery technology that is a direct, single-stage, catalytic process for converting sulfur dioxide to elemental sulfur. this catalytic process reduces SO{sub 2} over a fluorite-type oxide (such as ceria or zirconia). The catalytic activity can be significantly promoted by active transition metals, such as copper. More than 95% elemental sulfur yield, corresponding to almost complete sulfur dioxide conversion, was obtained over a Cu-Ce-O oxide catalyst as part of an ongoing DOE-sponsored University Coal Research Program. This type of mixed metal oxide catalyst has stable activity, high selectivity for sulfur production, and is resistant to water and carbon dioxide poisoning. Tests with CO and CH{sub 4} reducing gases indicates that the catalyst has the potential for flexibility with regard to the composition of the reducing gas, making it attractive for utility use. the performance of the catalyst is consistently good over a range of SO{sub 2} inlet concentration (0.1 to 10%) indicating its flexibility in treating SO{sub 2} tail gases as well as high concentration streams.

Benedek, K. [Little (Arthur D.), Inc., Cambridge, MA (United States); Flytzani-Stephanopoulos, M. [Tufts Univ., Medford, MA (United States)

1996-02-01T23:59:59.000Z

337

Functional carbons and carbon nanohybrids for the catalytic conversion of biomass to renewable chemicals in the condensed phase  

SciTech Connect (OSTI)

The production of chemicals from lignocellulosic biomass provides opportunities to synthesize chemicals with new functionalities and grow a more sustainable chemical industry. However, new challenges emerge as research transitions from petrochemistry to biorenewable chemistry. Compared to petrochemisty, the selective conversion of biomass-derived carbohydrates requires most catalytic reactions to take place at low temperatures (< 300?) and in the condensed phase to prevent reactants and products from degrading. The stability of heterogeneous catalysts in liquid water above the normal boiling point represents one of the major challenges to overcome. Herein, we review some of the latest advances in the field with an emphasis on the role of carbon materials and carbon nanohybrids in addressing this challenge.

Matthiesen, John; Hoff, Thomas; Liu, Chi; Pueschel, Charles; Rao, Radhika; Tessonnier, Jean-Philippe

2014-06-01T23:59:59.000Z

338

Ex-Situ Catalytic Fast Pyrolysis Technology Pathway  

SciTech Connect (OSTI)

In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This pathway case investigates converting woody biomass using ex-situ catalytic fast pyrolysis followed by upgrading to gasoline , diesel and jet range blendstocks . Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

Biddy, Mary J.; Dutta, Abhijit; Jones, Susanne B.; Meyer, Pimphan A.

2013-03-31T23:59:59.000Z

339

In-Situ Catalytic Fast Pyrolysis Technology Pathway  

SciTech Connect (OSTI)

In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This pathway case investigates converting woody biomass using in-situ catalytic fast pyrolysis followed by upgrading to gasoline, diesel, and jet range blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

Biddy, Mary J.; Dutta, Abhijit; Jones, Susanne B.; Meyer, Pimphan A.

2013-03-31T23:59:59.000Z

340

Catalytic Hydrogenation of Bio-Oil for Chemicals and Fuels  

SciTech Connect (OSTI)

The scope of work includes optimizing processing conditions and demonstrating catalyst lifetime for catalyst formulations that are readily scaleable to commercial operations. We use a bench-scale, continuous-flow, packed-bed, catalytic, tubular reactor, which can be operated in the range of 100-400 mL/hr., from 50-400 C and up to 20MPa (see Figure 1). With this unit we produce upgraded bio-oil from whole bio-oil or useful bio-oil fractions, specifically pyrolytic lignin. The product oils are fractionated, for example by distillation, for recovery of chemical product streams. Other products from our tests have been used in further testing in petroleum refining technology at UOP and fractionation for product recovery in our own lab. Further scale-up of the technology is envisioned and we will carry out or support process design efforts with industrial partners, such as UOP.

Elliott, Douglas C.

2006-02-14T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Methods and apparatus for catalytic hydrothermal gasification of biomass  

DOE Patents [OSTI]

Continuous processing of wet biomass feedstock by catalytic hydrothermal gasification must address catalyst fouling and poisoning. One solution can involve heating the wet biomass with a heating unit to a temperature sufficient for organic constituents in the feedstock to decompose, for precipitates of inorganic wastes to form, for preheating the wet feedstock in preparation for subsequent separation of sulfur contaminants, or combinations thereof. Treatment further includes separating the precipitates out of the wet feedstock, removing sulfur contaminants, or both using a solids separation unit and a sulfur separation unit, respectively. Having removed much of the inorganic wastes and the sulfur that can cause poisoning and fouling, the wet biomass feedstock can be exposed to the heterogeneous catalyst for gasification.

Elliott, Douglas C.; Butner, Robert Scott; Neuenschwander, Gary G.; Zacher, Alan H.; Hart, Todd R.

2012-08-14T23:59:59.000Z

342

Fabrication of fuel cell electrodes and other catalytic structures  

DOE Patents [OSTI]

A porous layer of catalyst material suitable for use as an electrode in a molten carbonate fuel cell includes elongated pores substantially extending across the layer thickness. The catalyst layer is prepared by depositing particulate catalyst material into polymeric flocking on a substrate surface by a procedure such as tape casting. The loaded substrate is heated in a series of steps with rising temperatures to set the tape, thermally decompose the substrate with flocking and sinter bond the catalyst particles into a porous catalytic layer with elongated pores across its thickness. Employed as an electrode, the elongated pores provide distribution of reactant gas into contact with catalyst particles wetted by molten electrolyte. 1 fig.

Smith, J.L.

1987-02-11T23:59:59.000Z

343

An Energy Analysis of the Catalytic Combustion Burner  

E-Print Network [OSTI]

ICEBO2006, Shenzhen, China Heating technologies for energy efficiency Vol.III-1-3 An Energy Analysis of the Catalytic Combustion Burner Qingshan Dong Postgraduate Shihong. Zhang Ph. D. Professor Zhiyin Duan Postgraduate Qi Zhou... for energy efficiency Vol.III-1-3 Tab. 1 Compositions of natural gas Compositions CH4 C2H6 C3H8 i-C4H10 n-C4H10 CO2 N2 O2 Volume fraction (%) 93.908 0.951 0.198 0.012 0.011 2.657 1.894 0.369 Lower heating value (kJ Nm-3) 35906 64397 93244 122857...

Dong, Q.; Zhang, S.; Duan, Z.; Zhou, Q.

2006-01-01T23:59:59.000Z

344

Studies of coupled chemical and catalytic coal conversion methods  

SciTech Connect (OSTI)

The objective of this research was to convert coal into a soluble substance under mild conditions. The strategy involved two steps, first to breakdown the macromolecular network of coal, and second to add hydrogen catalytically. We investigated different basic reagents that could, in priciple, break down coal's structure and alkylation strategies that might enhance its solubility. We examined O- and C-alkylation, the importance of the strength of the base, the character of the added alkyl groups and other reaction parameters. This work provided new information concerning the way in which hydrogen bonding, polarization interactions between aromatic structures and covalent bonding could be disrupted and solubility enhanced. The objective of our research was to explore new organochromium chemistry that might be feasible for the hydrogenation of coal under mild conditions.

Stock, L.M.; Chatterjee, K.; Cheng, C.; Ettinger, M.; Flores, F.; Jiralerspong, S.; Miyake, M.; Muntean, J.

1991-12-01T23:59:59.000Z

345

Studies of coupled chemical and catalytic coal conversion methods  

SciTech Connect (OSTI)

The objective of this research was to convert coal into a soluble substance under mild conditions. The strategy involved two steps, first to breakdown the macromolecular network of coal, and second to add hydrogen catalytically. We investigated different basic reagents that could, in priciple, break down coal`s structure and alkylation strategies that might enhance its solubility. We examined O- and C-alkylation, the importance of the strength of the base, the character of the added alkyl groups and other reaction parameters. This work provided new information concerning the way in which hydrogen bonding, polarization interactions between aromatic structures and covalent bonding could be disrupted and solubility enhanced. The objective of our research was to explore new organochromium chemistry that might be feasible for the hydrogenation of coal under mild conditions.

Stock, L.M.; Chatterjee, K.; Cheng, C.; Ettinger, M.; Flores, F.; Jiralerspong, S.; Miyake, M.; Muntean, J.

1991-12-01T23:59:59.000Z

346

Catalytic carbon membranes for hydrogen production. Final report  

SciTech Connect (OSTI)

Commercial carbon composite microfiltration membranes may be modified for gas separation applications by providing a gas separation layer with pores in the 1- to 10-nm range. Several organic polymeric precursors and techniques for depositing a suitable layer were investigated in this project. The in situ polymerization technique was found to be the most promising, and pure component permeation tests with membrane samples prepared with this technique indicated Knudsen diffusion behavior. The gas separation factors obtained by mixed-gas permeation tests were found to depend strongly on gas temperature and pressure indicating significant viscous flow at high-pressure conditions. The modified membranes were used to carry out simultaneous water gas shift reaction and product hydrogen separation. These tests indicated increasing CO conversions with increasing hydrogen separation. A simple process model was developed to simulate a catalytic membrane reactor. A number of simulations were carried out to identify operating conditions leading to product hydrogen concentrations over 90 percent. (VC)

Damle, A.S.; Gangwal, S.K.

1992-01-01T23:59:59.000Z

347

Catalytic gasification studies in a pressurized fluid-bed unit  

SciTech Connect (OSTI)

The purpose of the project is to evaluate the technical and economic feasibility of producing specific gas products via the catalytic gasification of biomass. This report presents the results of research conducted from October 1980 to November 1982. In the laboratory scale studis, active catalysts were developed for generation of synthesis gases from wood by steam gasification. A trimetallic catalyst, Ni-Co-Mo on silica-alumina doped with 2 wt % Na, was found to retain activity indefinitely for generation of a methanol synthesis gas from wood at 1380/sup 0/F (750/sup 0/C) and 1 atm (100 kPa) absolute pressure. Catalysts for generation of a methane-rich gas were deactivated rapidly and could not be regenerated as required for economic application. Sodium carbonate and potassium carbonate were effective as catalysts for conversion of wood to synthesis gases and methane-rich gas and should be economically viable. Catalytic gasification conditions were found to be suitable for processing of alternative feedstocks: bagasse, alfalfa, rice hulls, and almond hulls. The PDU was operated successfully at absolute pressures of up to 10 atm (1000 kPa) and temperatures of up to 1380/sup 0/F (750/sup 0/C). Yields of synthesis gases at elevated pressure were greater than those used for previous economic evaluations. A trimetallic catalyst, Ni-Cu-Mo on silica-alumina, did not display a long life as did the doped trimetallic catalyst used in laboratory studies. A computer program for a Radio Shack TRS-80 Model I microcomputer was developed to evaluate rapidly the economics of producing either methane or methanol from wood. The program is based on economic evaluations reported in previous studies. Improved yields from the PDU studies were found to result in a reduction of about 9 cents/gal in methanol cost.

Mudge, L.K.; Baker, E.G.; Mitchell, D.H.; Robertus, R.J.; Brown, M.D.

1983-07-01T23:59:59.000Z

348

Final Report: Investigation of Catalytic Pathways for Lignin Breakdown into Monomers and Fuels  

SciTech Connect (OSTI)

Lignin is a biopolymer that comprises up to 35% of woody biomass by dry weight. It is currently underutilized compared to cellulose and hemicellulose, the other two primary components of woody biomass. Lignin has an irregular structure of methoxylated aromatic groups linked by a suite of ether and alkyl bonds which makes it difficult to degrade selectively. However, the aromatic components of lignin also make it promising as a base material for the production of aromatic fuel additives and cyclic chemical feed stocks such as styrene, benzene, and cyclohexanol. Our laboratory research focused on three methods to selectively cleave and deoxygenate purified lignin under mild conditions: acidolysis, hydrogenation and electrocatalysis. (1) Acidolysis was undertaken in CH2Cl2 at room temperature. (2) Hydrogenation was carried out by dissolving lignin and a rhodium catalyst in 1:1 water:methoxyethanol under a 1 atm H2 environment. (3) Electrocatalysis of lignin involved reacting electrically generated hydrogen atoms at a catalytic palladium cathode with lignin dissolved in a solution of aqueous methanol. In all of the experiments, the lignin degradation products were identified and quantified by gas chromatography mass spectroscopy and flame ionization detection. Yields were low, but this may have reflected the difficulty in recovering the various fractions after conversion. The homogeneous hydrogenation of lignin showed fragmentation into monomers, while the electrocatalytic hydrogenation showed production of polyaromatic hydrocarbons and substituted benzenes. In addition to the experiments, promising pathways for the conversion of lignin were assessed. Three conversion methods were compared based on their material and energy inputs and proposed improvements using better catalyst and process technology. A variety of areas were noted as needing further experimental and theoretical effort to increase the feasibility of lignin conversion to fuels.

Gluckstein, Jeffrey A [ORNL; Hu, Michael Z. [ORNL; Kidder, Michelle [ORNL; McFarlane, Joanna [ORNL; Narula, Chaitanya Kumar [ORNL; Sturgeon, Matthew R [ORNL

2010-12-01T23:59:59.000Z

349

Catalytic Process for the Conversion of Coal-derived Syngas to Ethanol  

SciTech Connect (OSTI)

The catalytic conversion of coal-derived syngas to C{sub 2+} alcohols and oxygenates has attracted great attention due to their potential as chemical intermediates and fuel components. This is particularly true of ethanol, which can serve as a transportation fuel blending agent, as well as a hydrogen carrier. A thermodynamic analysis of CO hydrogenation to ethanol that does not allow for byproducts such as methane or methanol shows that the reaction: 2 CO + 4 H{sub 2} {yields} C{sub 2}H{sub 5}OH + H{sub 2}O is thermodynamically favorable at conditions of practical interest (e.g,30 bar, {approx}< 250 C). However, when methane is included in the equilibrium analysis, no ethanol is formed at any conditions even approximating those that would be industrially practical. This means that undesired products (primarily methane and/or CO{sub 2}) must be kinetically limited. This is the job of a catalyst. The mechanism of CO hydrogenation leading to ethanol is complex. The key step is the formation of the initial C-C bond. Catalysts that are selective for EtOH can be divided into four classes: (a) Rh-based catalysts, (b) promoted Cu catalysts, (c) modified Fischer-Tropsch catalysts, or (d) Mo-sulfides and phosphides. This project focuses on Rh- and Cu-based catalysts. The logic was that (a) Rh-based catalysts are clearly the most selective for EtOH (but these catalysts can be costly), and (b) Cu-based catalysts appear to be the most selective of the non-Rh catalysts (and are less costly). In addition, Pd-based catalysts were studied since Pd is known for catalyzing CO hydrogenation to produce methanol, similar to copper. Approach. The overall approach of this project was based on (a) computational catalysis to identify optimum surfaces for the selective conversion of syngas to ethanol; (b) synthesis of surfaces approaching these ideal atomic structures, (c) specialized characterization to determine the extent to which the actual catalyst has these structures, and (d) testing at realistic conditions (e.g., elevated pressures) and differential conversions (to measure true kinetics, to avoid deactivation, and to avoid condensable concentrations of products in the outlet gas).

James Spivery; Doug Harrison; John Earle; James Goodwin; David Bruce; Xunhau Mo; Walter Torres; Joe Allison Vis Viswanathan; Rick Sadok; Steve Overbury; Viviana Schwartz

2011-07-29T23:59:59.000Z

350

Tree SelectionTree Selection Why is selection important?  

E-Print Network [OSTI]

There are lists from different locations. Utility company Local tree board Native trees #12;Utility Company their list. #12;Tree Selection Style I Process Pick up trees Plant them #12;This could be the result! Is this tree right for this location? #12;Tree Selection Style II Let's try selection method 2. #12;Tree List

351

Landing of size-selected Agn clusters on single crystal TiO2 ,,110...-,,11...  

E-Print Network [OSTI]

-selected Agn + n=1,2,3 clusters with impact energy less than 2 eV per atom were deposited from the gas phase supports catalyze many reactions, including the oxidation of CO and small olefins1­4 has stimulated great interest in un- derstanding the nature of the catalytic activity, including the dependence on cluster size

Buratto, Steve

352

Column Experiments for Radionuclide Adsorption Studies of the Culebra Dolomite: Retardation Parameter Estimation for Non-Eluted Actinide Species  

SciTech Connect (OSTI)

The U.S. Department of Energy (DOE) has been developing a nuclear waste disposal facility, the Waste Isolation Pilot Plant (WIPP), located approximately 42 km east of Carlsbad, New Mexico. The WIPP is designed to demonstrate the safe disposal of transuranic wastes produced by the defense nuclear-weapons program. Performance assessment analyses (U.S. DOE, 1996) indicate that human intrusion by inadvertent and intermittent drilling for resources provide the only credible mechanisms for significant releases of radionuclides horn the disposal system. These releases may occur by five mechanisms: (1) cuttings, (2) cavings, (3) spallings, (4) direct brine releases, and (5) long-term brine releases. The first four mechanisms could result in immediate release of contaminant to the accessible environment. For the last mechanism, migration pathways through the permeable layers of rock above the Salado are important, and major emphasis is placed on the Culebra Member of the Rustler Formation because this is the most transmissive geologic layer in the disposal system. For reasons of initial quantity, half-life, and specific radioactivity, certain isotopes of Th, U, Am, and Pu would dominate calculated releases from the WIPP. In order to help quanti~ parameters for the calculated releases, radionuclide transport experiments have been carried out using five intact-core columns obtained from the Culebra dolomite member of the Rustler Formation within the Waste Isolation Pilot Plant (WIPP) site in southeastern New Mexico. This report deals primarily with results of mathematical analyses related to the retardation of %J%, 24%, and 24'Am in two of these cores (B-Core - VPX26-11A and C-Core - VPX28-6C). All B-Core transport experiments were done using Culebra-simukmt brine relevant to the core recovery location (the WIPP air-intake shaft - AIS). Most experiments with C-Core were done with AIS brine with some admixture of a brine composition (ERDA-6) that simulated deeper formation brines. No significant changes in transport behavior were observed for changes in brine. Hydraulic characteristics (i.e., apparent porosity and apparent dispersion coefficient) for the cores were obtained via experiments using conservative tracer `Na. Elution experiments carried out over periods of a few days with tracers `*U and %Np indicated that these tracers were weakly retarded as indicated by delayed elution of these species. Elution experiments with tracers `%, 24'Pu, and 24'Ani were performed, but no elution of any of these species was observed in any flow experiment to date, including experiments of up to two years duration. However, B-Core was subjected to tomographic analysis from which a retardation factor can be inferred for%. Moreover, the fact of non- elution for 24*Pu and 24'Am after more than two years brine flow through C-Core can be coupled with the minimum detectable activity for each of these species to compute minimum retardation factors in C-Core. The retardation factors for all three species can then be coupled with the apparent hydraulic characteristics to estimate an apparent minimum solutionhock distribution coefficient, &, for each actinide. The specific radionuclide isotopes used in these experiments were chosen to facilitate analysis. Even though these isotopes are not necessarily the same as those that are most important to WIPP performance, they are isotopes of the same elements, and . their chemical and transport properties are therefore identical to those of isotopes in the WIPP inventory. The retardation factors and & values deduced from experimental results strongly support the contention that sorption in the Culebra provides an effective barrier to release of Th, Pu, and Am during the regulatory period.

Brown, G.O.; Lucero, D.A.; Perkins, W.G.

1999-01-01T23:59:59.000Z

353

Effects of dispersion and support on adsorption, catalytic and electronic properties of cobalt/alumina CO hydrogenation catalysts: Annual progress report, August 1, 1987-July 31, 1988  

SciTech Connect (OSTI)

An investigation of the effects of surface structure, dispersion, and support on the adsorption, catalytic, and electronic properties of cobalt/alumina is described, the objectives of which are to determine (1) the effects of surface structure and metal dispersion on the adsorption and catalytic properties of cobalt and (2) the effects of decorating support species on metal crystallites and of direct electronic interactions between metal clusters and support, on the adsorption, catalytic and electronic properties of cobalt supported on alumina. During the first year effects of surface structure and dispersion on the adsorption, activity/selectivity, and electronic properties of Co/W single crystal surfaces and alumina-supported cobalt were investigated in a surface science investigation, lab reactor studies, TPD/TPSR studies, and a Moessbauer spectroscopy study. The structure, stability, surface electronic properties, and chemisorptive properties of vapor-deposited cobalt overlayers (0-4 ML) on W(110) and W(100) were studied by Auger electron spectroscopy, low energy electron diffraction, work function changes, and temperature programmed desorption (TPD) of cobalt, hydrogen, and carbon monoxide. The CO chemisorptive properties of the two cobalt overlayers are quite different, CO adsorption being dissociative on the W(100) surface and nondissociative on the W(110) surface; comparison of the results with those for Ni/W(100) indicate that Co/W(100) as a result of electronic interaction with the tungsten substrate. Activities and selectivities of cobalt/alumina catalysts for CO hydrogenation prepared by decomposition of Co/sub 4/(CO)/sub 12/ were determined as functions of metal loading, dispersion, and extent of reduction. Steady-state activity and product molecular weight were found to increase with increasing metal loading (decreasing dispersion and increasing extent of reduction). 10 refs.

Bartholomew, C.H.

1988-08-22T23:59:59.000Z

354

Oxygen transport membrane system and method for transferring heat to catalytic/process reactors  

DOE Patents [OSTI]

A method and apparatus for producing heat used in a synthesis gas production is provided. The disclosed method and apparatus include a plurality of tubular oxygen transport membrane elements adapted to separate oxygen from an oxygen containing stream contacting the retentate side of the membrane elements. The permeated oxygen is combusted with a hydrogen containing synthesis gas stream contacting the permeate side of the tubular oxygen transport membrane elements thereby generating a reaction product stream and radiant heat. The present method and apparatus also includes at least one catalytic reactor containing a catalyst to promote the stream reforming reaction wherein the catalytic reactor is surrounded by the plurality of tubular oxygen transport membrane elements. The view factor between the catalytic reactor and the plurality of tubular oxygen transport membrane elements radiating heat to the catalytic reactor is greater than or equal to 0.5.

Kelly, Sean M; Kromer, Brian R; Litwin, Michael M; Rosen, Lee J; Christie, Gervase Maxwell; Wilson, Jamie R; Kosowski, Lawrence W; Robinson, Charles

2014-01-07T23:59:59.000Z

355

Effects of copper catalytic reactions on the development of supersonic hydrogen flames  

SciTech Connect (OSTI)

Copper species are present in hydrogen flames in arc heated supersonic ramjet testing facilities. Homogeneous and heterogeneous copper catalytic reactions may affect the flame development by enhancing the recombination of hydrogen atoms. Computer simulation is used to investigate the effects of the catalytic reactions on the reaction and ignition times of the flames. The simulation uses a modified general chemical kinetics computer program to simulate the development of copper-contaminated hydrogen flames under scramjet testing conditions. Reaction times of hydrogen flames are found to be reduced due to the copper catalytic effects, but ignition times are much less sensitive to such effects. The reduction of reaction time depends on copper concentration, particle size (if copper is in the condensed phase), and Mach number (or initial temperature and pressure). As copper concentration increases or the particle size decreases, reaction time decreases. As Mach number increases (or pressure and temperature decrease), the copper catalytic effects are greater.

Chang, S.L.; Lottes, S.A.; Berry, G.F.

1992-10-01T23:59:59.000Z

356

argonaute-like catalytic triad: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

produc Kik, Pieter 93 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

357

Reaction kinetics of olefin saturation in the hydrodesulfurization of fluid catalytic cracked naphtha  

E-Print Network [OSTI]

U.S. governmental agencies are calling for strict environmental regulations on the quality of gasoline. Fluid catalytic cracked naphtha is an important blending component of the gasoline pool. The majority of the sulfur in the gasoline pool comes...

Schumann, Brian Herbert

2012-06-07T23:59:59.000Z

358

Comparison of Gas Catalytic and Electric Infrared Performance for Industrial Applications  

E-Print Network [OSTI]

A study was conducted to evaluate the performance of gas catalytic and electric infrared for industrial applications. The project focused on fabric drying, paper drying, metal heating, and plastic forming as target industrial applications. Tests...

Eshraghi, R. R.; Welch, D. E.

359

CO-CATALYTIC ABSORPTION LAYERS FOR CONTROLLED LASER-INDUCED CHEMICAL VAPOR DEPOSITION OF CARBON NANOTUBES  

E-Print Network [OSTI]

The concept of co-catalytic layer structures for controlled laser-induced chemical vapor deposition of carbon nanotubes is established, in which a thin Ta support layer chemically aids the initial Fe catalyst reduction. This enables a significant...

Michaelis, F.B.; Weatherup, R.S.; Bayer, B.C.; Bock, M.C.D; Sugime, H.; Caneva, S.; Robertson, J.; Baumberg, J.J.; Hofmann, S.

2014-02-24T23:59:59.000Z

360

Catalytic roles of Co0 and Co2+ during steam reforming of ethanol...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

roles of Co0 and Co2+ during steam reforming of ethanol on CoMgO catalysts . Catalytic roles of Co0 and Co2+ during steam reforming of ethanol on CoMgO catalysts . Abstract:...

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Nanostructured Materials Generated by High-Intensity Ultrasound: Sonochemical Synthesis and Catalytic  

E-Print Network [OSTI]

and Catalytic Studies Kenneth S. Suslick,* Taeghwan Hyeon, and Mingming Fang School of Chemical Sciences. Mater. 1991, 3, 30. (10) Klabunde, K. J.; Zhang, D.; Glavee, G. N.; Sorensen, C. M. Chem. Mater. 1994, 6

Suslick, Kenneth S.

362

Regional catalytic economic impacts and noise-damage costs of aviation growth  

E-Print Network [OSTI]

There is growing recognition that transportation or infrastructure improvements can have longer-term catalytic impacts economic productivity, which are in addition to the direct, indirect, or induced household spending ...

Tam, Ryan Aung Min, 1973-

2008-01-01T23:59:59.000Z

363

Enhanced thermal and gas flow performance in a three-way catalytic...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

thermal and gas flow performance in a three-way catalytic converter through use of insulation within the ceramic monolith Enhanced thermal and gas flow performance in a three-way...

364

Catalytic Hydrodeoxygenation of Methyl-Substituted Phenols: Correlations of Kinetic Parameters with Molecular Properties  

E-Print Network [OSTI]

. Introduction As a result of increasing environmental concerns, catalytic hydrotreating has become an important, oil shale, and tar sands would render the hydrotreating of oxygen-containing com- pounds, mostly

Simons, Jack

365

Catalytic Addition of Simple Alkenes to Carbonyl Compounds by Use of Group 10 Metals  

E-Print Network [OSTI]

Recent advances using nickel complexes in the activation of unactivated monosubstituted olefins for catalytic intermolecular carbon-carbon bond-forming reactions with carbonyl compounds, such as simple aldehydes, isocyanates, ...

Ho, Chun-Yu

366

Final Technical Report [Development of Catalytic Alkylation and Fluoroalkylation Methods  

SciTech Connect (OSTI)

In the early stages of this DOE-funded research project, we sought to prepare and study a well-defined nickel-alkyl complex containing tridentate nitrogen donor ligands. We found that reaction of (TMEDA)NiMe2 (1) with terpyridine ligand cleanly led to the formation of (terpyridyl)NiMe (2), which we also determined to be an active alkylation catalyst. The thermal stability of 2 was unlike that seen for any of the active pybox ligands, and enabled a number of key studies on alkyl transfer reactions to be performed, providing new insights into the mechanism of nickel-mediated alkyl-alkyl cross-coupling reactions. In addition to the mechanistic studies, we showed that the terpyridyl nickel compounds can catalytically cross-couple alkyl iodides in yields up to 98% and bromides in yields up to 46 %. The yields for the bromides can be increased up to 67 % when the new palladium catalyst [(tpy’)Pd-Ph]I is used. The best route to the targeted [(tpy)NiBr] (1) was found to involve the comproportionation reaction of [(dme)NiBr{sub 2}] and [Ni(COD){sub 2}] in the presence of two equivalents of terpyridine. This reaction was driven to high yields of product formation (72 % isolated) by the precipitation of 1 from THF solvent.

Vicic, David A.

2014-05-01T23:59:59.000Z

367

Effect of severity on catalytic hydroprocessed shale oil jet fuels  

SciTech Connect (OSTI)

Catalytic hydroprocessed shale oil jet fuels in the USA were characterized and compared with petroleum jet fuel to demonstrate their possibility as a conventional jet fuel substitute. The shale oils (Geokinetics, Occidental, Paraho and Tosco II) were hydrotreated in a 0.0508m ID by K1.524m long reactor containing Ni/Mo/Al/sub 2/O/sub 3/ catalyst. The fractionated hydrogenated shale oils at jet fuel ranges (120-300/degree/C) were analyzed for composition and physical properties. The increasing hydroprocessing severity proportionally decreased nitrogen, sulfur, olefins, aromatics and increased hydrogen content. The nitrogen content was considerable higher even at high severity conditions. Sulfur and olefin contents were lower at all severities. The heat of combustion and the physical properties, except the freezing point, were comparable to petroleum jet fuels. The yields of jet fuels increased proportionally to increased severity. The study showed that high severity hydroprocessing gave better performance in processing shale oils to jet fuels.

Mukherjee, N.L.

1987-01-01T23:59:59.000Z

368

TEC as electric generator in an automobile catalytic converter  

SciTech Connect (OSTI)

Modern cars use more and more electric power due to more on-board electric systems, e.g., ABS brakes, active suspension systems, electric windows, chair adjustment systems and electronic engine control systems. One possible energy source for electricity generation is to use the waste heat from the car`s engine, which generally is as much as 80% of the total energy from the combustion of the gasoline. Maybe the best location to tap the excess heat is the Catalytic Converter (Cat) in the exhaust system or perhaps at the exhaust pipes close to the engine. The Cat must be kept within a certain temperature interval. Large amounts of heat are dissipated through the wall of the Cat. A Thermionic Energy Converter (TEC) in coaxial form could conveniently be located around the ceramic cartridge of the Cat. Since the TEC is a rather good heat insulator before it reaches its working temperature the Cat will reach working temperature faster, and the final temperature of it can be controlled better when encapsulated in a concentric TEC arrangement. It is also possible to regulate the temperature of the Cat and the TEC by controlling the electrical load of the TEC. The possible working temperatures of present and future Cats appear very suitable for the new low work function collector TEC, which has been demonstrated to work down to 470 K.

Svensson, R. [Chalmers Univ. of Technology, Goeteborg (Sweden); Holmlid, L. [Univ. of Goeteborg (Sweden). Dept. of Physical Chemistry

1996-12-31T23:59:59.000Z

369

Low-temperature catalytic gasification of wet industrial wastes  

SciTech Connect (OSTI)

Bench-scale reactor tests are in progress at Pacific Northwest Laboratory to develop a low-temperature, catalytic gasification system. The system, licensed under the trade name Thermochemical Environmental Energy System (TEES{reg sign}), is designed for treating a wide variety of feedstocks ranging from dilute organics in water to waste sludges from food processing. This report describes a test program which used a continuous-feed tubular reactor. This test program is an intermediate stage in the process development. The reactor is a laboratory-scale version of the commercial concept as currently envisioned by the process developers. An energy benefit and economic analysis was also completed on the process. Four conceptual commercial installations of the TEES process were evaluated for three food processing applications and one organic chemical manufacturing application. Net energy production (medium-Btu gas) was achieved in all four cases. The organic chemical application was found to be economically attractive in the present situation. Based on sensitivity studies included in the analysis, the three food processing cases will likely become attractive in the near future as waste disposal regulations tighten and disposal costs increase. 21 refs., 2 figs., 9 tabs.

Elliott, D C; Neuenschwander, G G; Baker, E G; Sealock, Jr, L J; Butner, R S

1991-04-01T23:59:59.000Z

370

Mercury Oxidation via Catalytic Barrier Filters Phase II  

SciTech Connect (OSTI)

In 2004, the Department of Energy National Energy Technology Laboratory awarded the University of North Dakota a Phase II University Coal Research grant to explore the feasibility of using barrier filters coated with a catalyst to oxidize elemental mercury in coal combustion flue gas streams. Oxidized mercury is substantially easier to remove than elemental mercury. If successful, this technique has the potential to substantially reduce mercury control costs for those installations that already utilize baghouse barrier filters for particulate removal. Completed in 2004, Phase I of this project successfully met its objectives of screening and assessing the possible feasibility of using catalyst coated barrier filters for the oxidation of vapor phase elemental mercury in coal combustion generated flue gas streams. Completed in September 2007, Phase II of this project successfully met its three objectives. First, an effective coating method for a catalytic barrier filter was found. Second, the effects of a simulated flue gas on the catalysts in a bench-scale reactor were determined. Finally, the performance of the best catalyst was assessed using real flue gas generated by a 19 kW research combustor firing each of three separate coal types.

Wayne Seames; Michael Mann; Darrin Muggli; Jason Hrdlicka; Carol Horabik

2007-09-30T23:59:59.000Z

371

Structural Basis for Catalytic Activation of a Serine Recombinase  

SciTech Connect (OSTI)

Sin resolvase is a site-specific serine recombinase that is normally controlled by a complex regulatory mechanism. A single mutation, Q115R, allows the enzyme to bypass the entire regulatory apparatus, such that no accessory proteins or DNA sites are required. Here, we present a 1.86 {angstrom} crystal structure of the Sin Q115R catalytic domain, in a tetrameric arrangement stabilized by an interaction between Arg115 residues on neighboring subunits. The subunits have undergone significant conformational changes from the inactive dimeric state previously reported. The structure provides a new high-resolution view of a serine recombinase active site that is apparently fully assembled, suggesting roles for the conserved active site residues. The structure also suggests how the dimer-tetramer transition is coupled to assembly of the active site. The tetramer is captured in a different rotational substate than that seen in previous hyperactive serine recombinase structures, and unbroken crossover site DNA can be readily modeled into its active sites.

Keenholtz, Ross A.; Rowland, Sally-J.; Boocock, Martin R.; Stark, W. Marshall; Rice, Phoebe A. (Glasgow); (UC)

2014-10-02T23:59:59.000Z

372

Effect of support on catalytic behavior of dispersed rhodium for hydrocarbon hydrogenolyses  

E-Print Network [OSTI]

EFFFCT OF SUPPORT ON CATALYTIC BEHAVIOR OF DISPERSED RHODIUM POR HYDROCARBON HYDROGENOLYSES A Thesis AMINA ARMED KHAL'lFA Submi I ted to the Graduate College of Texas AKM University in partial full illment of the requirement for the degree... of MASTER OF SCIENCE December 1986 Major Subject: Chemistry EFFECT OF SUPPORT ON CATALYTIC BEHAVIOR OF DISPERSED RHODIUM FOR HYDROCARBON HYDROGENOLYSES A Thesis by AMINA AHMED KHALIFA Approved as to style and content by: M. P. osynek (Chairman...

Khalifa, Amina Ahmed

2012-06-07T23:59:59.000Z

373

Using Ionic Liquids in Selective Hydrocarbon Conversion Processes  

SciTech Connect (OSTI)

This is the Final Report of the five-year project Using Ionic Liquids in Selective Hydrocarbon Conversion Processes (DE-FC36-04GO14276, July 1, 2004- June 30, 2009), in which we present our major accomplishments with detailed descriptions of our experimental and theoretical efforts. Upon the successful conduction of this project, we have followed our proposed breakdown work structure completing most of the technical tasks. Finally, we have developed and demonstrated several optimized homogenously catalytic methane conversion systems involving applications of novel ionic liquids, which present much more superior performance than the Catalytica system (the best-to-date system) in terms of three times higher reaction rates and longer catalysts lifetime and much stronger resistance to water deactivation. We have developed in-depth mechanistic understandings on the complicated chemistry involved in homogenously catalytic methane oxidation as well as developed the unique yet effective experimental protocols (reactors, analytical tools and screening methodologies) for achieving a highly efficient yet economically feasible and environmentally friendly catalytic methane conversion system. The most important findings have been published, patented as well as reported to DOE in this Final Report and our 20 Quarterly Reports.

Tang, Yongchun; Periana, Roy; Chen, Weiqun; van Duin, Adri; Nielsen, Robert; Shuler, Patrick; Ma, Qisheng; Blanco, Mario; Li, Zaiwei; Oxgaard, Jonas; Cheng, Jihong; Cheung, Sam; Pudar, Sanja

2009-09-28T23:59:59.000Z

374

Coke gasification: the influence and behavior of inherent catalytic mineral matter  

SciTech Connect (OSTI)

Gasification of coke contributes to its degradation in the blast furnace. In this study, the effect of gasification on the inherent catalytic minerals in cokes and their reciprocal influence on gasification are investigated. The catalytic mineral phases identified in the cokes used in this study were metallic iron, iron sulfides, and iron oxides. Metallic iron and pyrrhotite were rapidly oxidized during gasification to iron oxide. The catalysts had a strong influence on the apparent rates at the initial stages of reaction. As gasification proceeds, their effect on the reaction rate diminishes as a result of reducing the surface contact between catalyst and carbon matrix because of carbon consumption around the catalyst particles; with extended burnout the reactivity of the coke becomes increasingly dependent on surface area. The reaction rate in the initial stages was also influenced by the particle size of the catalytic minerals; for a given catalytic iron level, the cokes whose catalytic minerals were more finely dispersed had a higher apparent reaction rate than cokes containing larger catalytic particles. Iron, sodium, and potassium in the amorphous phase did not appear to affect the reaction rate. 40 refs., 16 figs., 6 tabs.

Mihaela Grigore; Richard Sakurovs; David French; Veena Sahajwalla [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Bangor, NSW (Australia)

2009-04-15T23:59:59.000Z

375

Catalytic multi-stage process for hydroconversion and refining hydrocarbon feeds  

DOE Patents [OSTI]

A multi-stage catalytic hydrogenation and hydroconversion process for heavy hydrocarbon feed materials such as coal, heavy petroleum fractions, and plastic waste materials. In the process, the feedstock is reacted in a first-stage, back-mixed catalytic reactor with a highly dispersed iron-based catalyst having a powder, gel or liquid form. The reactor effluent is pressure-reduced, vapors and light distillate fractions are removed overhead, and the heavier liquid fraction is fed to a second stage back-mixed catalytic reactor. The first and second stage catalytic reactors are operated at 700-850.degree. F. temperature, 1000-3500 psig hydrogen partial pressure and 20-80 lb./hr per ft.sup.3 reactor space velocity. The vapor and light distillates liquid fractions removed from both the first and second stage reactor effluent streams are combined and passed to an in-line, fixed-bed catalytic hydrotreater for heteroatom removal and for producing high quality naphtha and mid-distillate or a full-range distillate product. The remaining separator bottoms liquid fractions are distilled at successive atmospheric and vacuum pressures, low and intermediate-boiling hydrocarbon liquid products are withdrawn, and heavier distillate fractions are recycled and further upgraded to provide additional low-boiling hydrocarbon liquid products. This catalytic multistage hydrogenation process provides improved flexibility for hydroprocessing the various carbonaceous feedstocks and adjusting to desired product structures and for improved economy of operations.

Comolli, Alfred G. (Yardley, PA); Lee, Lap-Keung (Cranbury, NJ)

2001-01-01T23:59:59.000Z

376

CATALYTIC GASIFICATION OF COAL USING EUTECTIC SALT MIXTURES  

SciTech Connect (OSTI)

The Gas Research Institute (GRI) estimates that by the year 2010, 40% or more of U.S. gas supply will be provided by supplements including substitute natural gas (SNG) from coal. These supplements must be cost competitive with other energy sources. The first generation technologies for coal gasification e.g. the Lurgi Pressure Gasification Process and the relatively newer technologies e.g. the KBW (Westinghouse) Ash Agglomerating Fluidized-Bed, U-Gas Ash Agglomerating Fluidized-Bed, British Gas Corporation/Lurgi Slagging Gasifier, Texaco Moving-Bed Gasifier, and Dow and Shell Gasification Processes, have several disadvantages. These disadvantages include high severities of gasification conditions, low methane production, high oxygen consumption, inability to handle caking coals, and unattractive economics. Another problem encountered in catalytic coal gasification is deactivation of hydroxide forms of alkali and alkaline earth metal catalysts by oxides of carbon (CO{sub x}). To seek solutions to these problems, a team consisting of Clark Atlanta University (CAU, a Historically Black College and University, HBCU), the University of Tennessee Space Institute (UTSI) and Georgia Institute of Technology (Georgia Tech) proposed to identify suitable low melting eutectic salt mixtures for improved coal gasification. The research objectives of this project were to: Identify appropriate eutectic salt mixture catalysts for coal gasification; Assess agglomeration tendency of catalyzed coal; Evaluate various catalyst impregnation techniques to improve initial catalyst dispersion; Determine catalyst dispersion at high carbon conversion levels; Evaluate effects of major process variables (such as temperature, system pressure, etc.) on coal gasification; Evaluate the recovery, regeneration and recycle of the spent catalysts; and Conduct an analysis and modeling of the gasification process to provide better understanding of the fundamental mechanisms and kinetics of the process.

Dr. Yaw D. Yeboah; Dr. Yong Xu; Dr. Atul Sheth; Dr. Pradeep Agrawal

2001-12-01T23:59:59.000Z

377

Candidate Selection Instrument  

Broader source: Energy.gov [DOE]

The candidate selection instrument is designed to take the guesswork out of selecting candidates for the various career development programs of interest. The instrument is straightforward and...

378

Undergraduate Program Selection Process  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Selection Process Undergraduate Program Selection Process Point your career towards Los Alamos Lab: work with the best minds on the planet in an inclusive environment that is rich...

379

ADVANCED BYPRODUCT RECOVERY: DIRECT CATALYTIC REDUCTION OF SO2 TO ELEMENTAL SULFUR  

SciTech Connect (OSTI)

Arthur D. Little, Inc., together with its commercialization partner, Engelhard Corporation, and its university partner Tufts, investigated a single-step process for direct, catalytic reduction of sulfur dioxide from regenerable flue gas desulfurization processes to the more valuable elemental sulfur by-product. This development built on recently demonstrated SO{sub 2}-reduction catalyst performance at Tufts University on a DOE-sponsored program and is, in principle, applicable to processing of regenerator off-gases from all regenerable SO{sub 2}-control processes. In this program, laboratory-scale catalyst optimization work at Tufts was combined with supported catalyst formulation work at Engelhard, bench-scale supported catalyst testing at Arthur D. Little and market assessments, also by Arthur D. Little. Objectives included identification and performance evaluation of a catalyst which is robust and flexible with regard to choice of reducing gas. The catalyst formulation was improved significantly over the course of this work owing to the identification of a number of underlying phenomena that tended to reduce catalyst selectivity. The most promising catalysts discovered in the bench-scale tests at Tufts were transformed into monolith-supported catalysts at Engelhard. These catalyst samples were tested at larger scale at Arthur D. Little, where the laboratory-scale results were confirmed, namely that the catalysts do effectively reduce sulfur dioxide to elemental sulfur when operated under appropriate levels of conversion and in conditions that do not contain too much water or hydrogen. Ways to overcome those limitations were suggested by the laboratory results. Nonetheless, at the end of Phase I, the catalysts did not exhibit the very stringent levels of activity or selectivity that would have permitted ready scale-up to pilot or commercial operation. Therefore, we chose not to pursue Phase II of this work which would have included further bench-scale testing, scale-up, pilot-scale (0.5 MW{sub e}) testing at conditions representative of various regenerable SO{sub 2}-control systems, preparation of a commercial process design, and development of a utility-scale demonstration plan.

Robert S. Weber

1999-05-01T23:59:59.000Z

380

Energy Conservation Revamps in Fluid Catalytic Cracking Systems  

E-Print Network [OSTI]

in the vapor recovery unit. By selecting the proper location and rates of side pump around streams, heat available in the main column can be used to reboil most or all of the VRU towers. Revamps of this type may be undertaken as stand alone energy conservation...

Wilson, J. W.; Sloan, H. D.

1984-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Catalytic oxidation of light alkanes in presence of a base  

DOE Patents [OSTI]

The presence of a base in the reaction mixture in a metal-ligand catalyzed partial oxidation of alkanes results in sustained catalyst activity, and in greater percent conversion as compared with oxidation in the absence of base, while maintaining satisfactory selectivity for the desired oxidation, for example the oxidation of isobutane to isobutanol.

Bhinde, Manoj V. (Boothwyn, PA); Bierl, Thomas W. (West Chester, PA)

1998-01-01T23:59:59.000Z

382

Catalytic oxidation of light alkanes in presence of a base  

DOE Patents [OSTI]

The presence of a base in the reaction mixture in a metal-ligand catalyzed partial oxidation of alkanes results in sustained catalyst activity, and in greater percent conversion as compared with oxidation in the absence of base, while maintaining satisfactory selectivity for the desired oxidation, for example the oxidation of isobutane to isobutanol. 1 fig.

Bhinde, M.V.; Bierl, T.W.

1998-03-03T23:59:59.000Z

383

Mental retardation, congenital heart defect, cleft palate, short stature, and facial anomalies: A new X-linked multiple congenital anomalies/mental retardation syndrome: Clinical description and molecular studies  

SciTech Connect (OSTI)

We report on two brothers and their two maternal uncles with severe mental retardation, congenital heart defect, cleft or highly arched palate, short stature and craniofacial anomalies consisting of microcephaly, abnormal ears, bulbous nose, broad nasal bridge, malar hypoplasia, and micro-gnathia. Three of the four patients died at an early age. The mother of the two brothers had an atrial septal defect. She is assumed to be manifesting carrier of a mutant gene, which is expressed in her two sons and two brothers. By multipoint linkage analysis it is found that the most likely location of the responsible gene is the pericentromeric region Xp21.3-q21.3 with DMD and DXS3 as flanking markers. Maximum information is obtained with marker DXS453 (Z = 1.20 at {theta} = 0.0). 24 refs., 12 figs., 1 tab.

Hamel, B.C.J.; Mariman, E.C.M.; Beersum, S.E.C. van; Ropers, H.H. [University Hospital, Nijmegen (Netherlands); Schoonbrood-Lenssen, A.M.J. [Institute for the Mentally Retarded, Echt (Netherlands)

1994-07-15T23:59:59.000Z

384

From First Principles Design to Realization of Bimetallic Catalysts for Enhanced Selectivity  

SciTech Connect (OSTI)

“Catalysis by design” has been a dream for decades. To specify the composition and structure of matter to effect a desired catalytic transformation with desired and predicted rate and selectivity remains a monumental challenge, especially in heterogeneous catalysis. Our research thrusts have been chosen not only for their practical and scientific relevance, e.g. for more efficient and sustainable chemicals and fuels production, but also because they provide a foundation for developing and exploring broadly applicable principles and strategies for catalyst design.

Lobo, Raul F.; Crooks, Richard M.; Mavrikakis, Manos

2014-04-08T23:59:59.000Z

385

Catalytic activation of carbon monoxide on metal surfaces  

SciTech Connect (OSTI)

In discussing the important basic aspects of carbon monoxide chemistry, this review covers the adsorption and reaction of CO with H/sub 2/O and H/sub 2/ on reduced metal surfaces. Carbon monoxide adsorption of the Group VIII metals exhibits certain patterns. Typically, as coverages exceed one-half, compression occurs in the monolayer and the molecules lose registry with the surface metal atoms. Particular sites associated with rough surfaces facilitate CO dissociation to the surface carbon; these sites may have a significant effect on selectivity in the CO hydrogenation reaction. The support used and the metal crystallite size both affect the catalyst activity and product selectivity. Indications are strong that a better knowledge of metal-support interactions combined with a more complete understanding of the surface chemistry involved will lead to improved catalyst systems in the future.

Vannice, M.A.

1982-01-01T23:59:59.000Z

386

Superior catalysts for selective catalytic reduction of nitric oxides; Quarterly technical progress report, October 1, 1993--December 31, 1993  

SciTech Connect (OSTI)

Work was done in three tasks during the first quarter. In Task 1, a new SCR reactor system has been built, complete with on-line GC and MS analyses. The GC is used to monitor the N{sub 2} product so the NO{sub x} > N{sub 2} conversion can be calculated. The MS is used to analyze the N{sub 2}0 concentration. In addition, a wet analytical technique has been established for SO{sub 3} analysis. The new SCR system and the SO{sub 3} analytical technique have been subjected to shakedown tests with success. Along with the existing SCR reactor system, there are now two systems that are being run independently. In Task 2, a procedure for the synthesis of stable Fe{sub 2}O{sub 3} Pillared clay has been established. Inductive coupled plasma spectrometric analysis (ICP) has been used to analyze the chemical composition of the Fe{sub 2}O{sub 3} Pillared clay. Preliminary results for the SCR activities of the Fe{sub 2}O{sub 3} pillared clay are obtained in Task 3. The results show that the activities are near that of the commercial V{sub 2}O{sub 5}/TiO{sub 2} catalysts. However, the SO{sub 2}-to-SO{sub 3} conversion is substantially lower with the pillared clay catalyst, which could be an important advantage.

Chen, J.P.; Cheng, L.S.; Kikkinides, E.S.; Yang, R.T.

1993-12-31T23:59:59.000Z

387

Silver ion mediated shape control of platinum nanoparticles: Removal of silver by selective etching leads to increased catalytic activity  

E-Print Network [OSTI]

AirGas, CP grade), hydrogen (Praxair, UHP, Reaction99.999%) and helium (Praxair, UHP, 99.999%) were used as-

Grass, Michael E.

2008-01-01T23:59:59.000Z

388

Selective catalytic reduction system and process for treating NOx emissions using a zinc or titanium promoted palladium-zirconium catalyst  

SciTech Connect (OSTI)

A process and system (18) for reducing NO.sub.x in a gas using hydrogen as a reducing agent is provided. The process comprises contacting the gas stream (29) with a catalyst system (38) comprising sulfated zirconia washcoat particles (41), palladium, a pre-sulfated zirconia binder (44), and a promoter (45) comprising at least one of titanium, zinc, or a mixture thereof. The presence of zinc or titanium increases the resistance of the catalyst system to a sulfur and water-containing gas stream.

Sobolevskiy, Anatoly (Orlando, FL); Rossin, Joseph A. (Columbus, OH); Knapke, Michael J. (Columbus, OH)

2011-08-02T23:59:59.000Z

389

Effects of a Zeolite-Selective Catalytic Reduction System on Comprehensive Emissions from a Heavy-Duty Diesel Engine  

E-Print Network [OSTI]

-Duty Diesel Engine Z. Gerald Liu and Devin R. Berg Cummins Emission Solutions, Stoughton, WI James J. Schauer spec- trum of chemical species from diesel engine emissions were investigated in this study with established procedures and com- pared between the measurements taken from a baseline heavy-duty diesel engine

Wu, Mingshen

390

In-line localized monitoring of catalyst activity in selective catalytic NO.sub.x reduction systems  

DOE Patents [OSTI]

Localized catalyst activity in an SCR unit for controlling emissions from a boiler, power plant, or any facility that generates NO.sub.x-containing flue gases is monitored by one or more modules that operate on-line without disrupting the normal operation of the facility. Each module is positioned over a designated lateral area of one of the catalyst beds in the SCR unit, and supplies ammonia, urea, or other suitable reductant to the catalyst in the designated area at a rate that produces an excess of the reductant over NO.sub.x on a molar basis through the designated area. Sampling probes upstream and downstream of the designated area draw samples of the gas stream for NO.sub.x analysis, and the catalyst activity is determined from the difference in NO.sub.x levels between the two probes.

Muzio, Lawrence J. (Laguna Niguel, CA); Smith, Randall A. (Huntington Beach, CA)

2009-12-22T23:59:59.000Z

391

Adaptive PI control of NOx? emissions in a Urea Selective Catalytic Reduction System using system identification models  

E-Print Network [OSTI]

The Urea SCR System has shown great potential for implementation on diesel vehicles wanting to meet the upcoming emission regulations by the EPA. The objective of this thesis is to develop an adaptive controller that is ...

Ong, Chun Yang

2009-01-01T23:59:59.000Z

392

The catalytic oxidation of propane and propylene with air: total aldehyde production and selectivity at low conversions.  

E-Print Network [OSTI]

~ Ths writer is izntebteg to pr, P G~ ~och Tor his assistance azsi guidance in this work aC to Br~ J+ 9 Kinds Tor his aery. suggestions eel Succor~ a The oxidation cf propane~ propylene and prcya~cregyimm mbetccres ctver a ~ aiucdna ~st in a flew... formation of aldehyde fran pure grade propane The ~ce of Within the range of variables of this investigation and with propylene ~& aldehyde pr~cn was f'ennd to bs independent of" residence Qorrcgations relating aldehyde pressure to ~ and cncygsn pressure...

Looney, Franklin Sittig

1950-01-01T23:59:59.000Z

393

Structural, textural and catalytic properties of Al-, Ti-pillared clays  

SciTech Connect (OSTI)

Al-, Ti- and Zr-pillared clays were characterized and NiMo/Pilc`s were tested in HDS reactions. The combination of activity measurements with Moessbauer Spectroscopy and x-ray microanalysis at microscopical scale give insight in the metal phases migration during pillaring, reaction and regeneration steps. {Alpha}-Fe phase in free Fe{sub 2}O{sub 3} islands predominate together with structural Fe{sup 3+} phase, but during the catalytic reaction Fe{sup 2+} forms. Delamination of the Ti- and Zr-Clay supports, together with high Lewis acidity might enhance their catalytic properties.

Ramos-Galvan, C.E.; Dominguez, J.M.; Sandoval-Robles, G.; Castillo-Mares, A.; Nava E, N.

1996-12-31T23:59:59.000Z

394

The Effects of Trace Contaminants on Catalytic Processing of Biomass-Derived Feedstocks  

SciTech Connect (OSTI)

Trace components in biomass feedstocks are potential catalyst poisons when catalytically processing these materials to value-added chemical products. Trace components include inorganic elements such as alkali metals and alkaline earths, phosphorus or sulfur, aluminum or silicon, chloride, or transition metals. Protein components in biomass feedstocks can lead to formation of peptide fractions (from hydrolysis) or ammonium ions (from more severe breakdown) both of which might interfere with catalysis. The effects of these components on catalytic hydrogenation processing has been studied in batch reactor processing tests

Elliott, Douglas C.; Peterson, Keith L.; Muzatko, Danielle S.; Alderson, Eric V.; Hart, Todd R.; Neuenschwander, Gary G.

2004-03-25T23:59:59.000Z

395

Hydrogen ions produced by plasma-assisted catalytic ionization using nickel grid  

SciTech Connect (OSTI)

Positive and negative hydrogen ions are produced by plasma-assisted catalytic ionization using a nickel grid, where the irradiation current density of positive ions onto the grid can be controlled by the discharge power. The irradiation energy can be controlled by both the grid potential and the discharge plasma potential. Extraction properties and energy distributions of positive and negative ions produced in the cases of using the grid and a porous nickel plate are compared. Two production mechanisms of negative ions are found in the process of plasma-assisted catalytic ionization.

Oohara, W.; Kawata, K.; Hibino, T. [Department of Electronic Device Engineering, Yamaguchi University, Ube 755-8611 (Japan)] [Department of Electronic Device Engineering, Yamaguchi University, Ube 755-8611 (Japan)

2013-06-15T23:59:59.000Z

396

Development of Micro Catalytic Combustor Using Ceramic Tape Casting Takashi OKAMASA, Gwang-Goo LEE, Yuji SUZUKI, and Nobuhide KASAGI  

E-Print Network [OSTI]

Development of Micro Catalytic Combustor Using Ceramic Tape Casting Takashi OKAMASA, Gwang-Goo LEE@thtlab.t.u-tokyo.ac.jp Abstract Micro-scale catalytic combustor fueled by butane is investigated. A cost-effective ceramic combustor is developed using high- precision tape-casting technology. Nano-porous alumina fabricated through

Kasagi, Nobuhide

397

Diffusion and Catalytic Cracking of 1,3,5 Tri-iso-propyl-benzene in FCC Catalysts  

E-Print Network [OSTI]

1 Diffusion and Catalytic Cracking of 1,3,5 Tri-iso- propyl-benzene in FCC Catalysts S.Al-Khattaf1 describes catalytic cracking experiments developed in a novel CREC Riser Simulator using 1,3,5-Tri-iso

Al-Khattaf, Sulaiman

398

Low-Temperature Catalytic Process To Produce Hydrocarbons From Sugars  

DOE Patents [OSTI]

Disclosed is a method of producing hydrogen from oxygenated hydrocarbon reactants, such as methanol, glycerol, sugars (e.g. glucose and xylose), or sugar alcohols (e.g. sorbitol). The method takes place in the condensed liquid phase. The method includes the steps of reacting water and a water-soluble oxygenated hydrocarbon in the presence of a metal-containing catalyst. The catalyst contains a metal selected from the group consisting of Group VIIIB transitional metals, alloys thereof, and mixtures thereof. The disclosed method can be run at lower temperatures than those used in the conventional steam reforming of alkanes.

Cortright, Randy D. (Madison, WI); Dumesic, James A. (Verona, WI)

2005-11-15T23:59:59.000Z

399

Optical Broadband Angular Selectivity  

E-Print Network [OSTI]

Light selection based purely on the angle of propagation is a long-standing scientific challenge. In angularly selective systems, however, the transmission of light usually also depends on the light frequency. We tailored ...

Shen, Yichen

400

Graduate Program Selection Process  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Selection Process Graduate Program Selection Process Point your career towards Los Alamos Lab: work with the best minds on the planet in an inclusive environment that is rich in...

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Bubbling bed catalytic hydropyrolysis process utilizing larger catalyst particles and smaller biomass particles featuring an anti-slugging reactor  

SciTech Connect (OSTI)

This invention relates to a process for thermochemically transforming biomass or other oxygenated feedstocks into high quality liquid hydrocarbon fuels. In particular, a catalytic hydropyrolysis reactor, containing a deep bed of fluidized catalyst particles is utilized to accept particles of biomass or other oxygenated feedstocks that are significantly smaller than the particles of catalyst in the fluidized bed. The reactor features an insert or other structure disposed within the reactor vessel that inhibits slugging of the bed and thereby minimizes attrition of the catalyst. Within the bed, the biomass feedstock is converted into a vapor-phase product, containing hydrocarbon molecules and other process vapors, and an entrained solid char product, which is separated from the vapor stream after the vapor stream has been exhausted from the top of the reactor. When the product vapor stream is cooled to ambient temperatures, a significant proportion of the hydrocarbons in the product vapor stream can be recovered as a liquid stream of hydrophobic hydrocarbons, with properties consistent with those of gasoline, kerosene, and diesel fuel. Separate streams of gasoline, kerosene, and diesel fuel may also be obtained, either via selective condensation of each type of fuel, or via later distillation of the combined hydrocarbon liquid.

Marker, Terry L; Felix, Larry G; Linck, Martin B; Roberts, Michael J

2014-09-23T23:59:59.000Z

402

Evidence of the production of hot hydrogen atoms in RF plasmas by catalytic reactions between hydrogen and oxygen species  

E-Print Network [OSTI]

Selective H-atom line broadening was found to be present throughout the volume (13.5 cm ID x 38 cm length) of RF generated H2O plasmas in a GEC cell. Notably, at low pressures (ca. hydrogen was 'hot' with energies greater than 40 eV with a pressure dependence, but only a weak power dependence. The degree of broadening was virtually independent of the position studied within the GEC cell, similar to the recent finding for He/H2 and Ar/H2 plasmas in the same GEC cell. In contrast to the atomic hydrogen lines, no broadening was observed in oxygen species lines at low pressures. Also, in control Xe/H2 plasmas run in the same cell at similar pressures and adsorbed power, no significant broadening of atomic hydrogen, Xe, or any other lines was observed. Stark broadening or acceleration of charged species due to high electric fields can not explain the results since (i) the electron density was insufficient by orders of magnitude, (ii) the RF field was essentially confined to the cathode fall region in contrast to the broadening that was independent of position, and (iii) only the atomic hydrogen lines were broadened. Rather, all of the data is consistent with a model that claims specific, predicted, species can act catalytically through a resonant energy transfer mechanism to create hot hydrogen atoms in plasmas.

Jonathan Phillips; Chun Ku Chen; Randell Mills

2004-02-06T23:59:59.000Z

403

Method and apparatus to selectively reduce NO.sub.x in an exhaust gas feedstream  

SciTech Connect (OSTI)

A method and apparatus are described to selectively reduce NO.sub.x emissions of an internal combustion engine. An exhaust aftertreatment system includes an injection device operative to dispense a hydrocarbon reductant upstream of a silver-alumina catalytic reactor device. A control system determines a NO.sub.x concentration and hydrocarbon/NOx ratio based upon selected parameters of the exhaust gas feedstream and dispenses hydrocarbon reductant during lean engine operation. Included is a method to control elements of the feedstream during lean operation. The hydrocarbon reductant may include engine fuel.

Schmieg, Steven J. (Troy, MI); Blint, Richard J. (Shelby Township, MI); Den, Ling (Sterling Heights, MI); Viola, Michael B. (Macomb Township, MI); Lee, Jong-Hwan (Rochester Hills, MI)

2011-08-30T23:59:59.000Z

404

Effects of Reduction Temperature and Metal-Support Interactions on the Catalytic Activity of Pt/g-Al2O3 and Pt/TiO2 for the Oxidation of CO in the Presence and Absence of H2.  

SciTech Connect (OSTI)

TiO2- and -Al2O3-supported Pt catalysts were characterized by HRTEM, XPS, EXAFS, and in situ FTIR spectroscopy after activation at various conditions, and their catalytic properties were examined for the oxidation of CO in the absence and presence of H2 (PROX). When {gamma}-Al{sub 2}O{sub 3} was used as the support, the catalytic, electronic, and structural properties of the Pt particles formed were not affected substantially by the pretreatment conditions. In contrast, the surface properties and catalytic activity of Pt/TiO2 were strongly influenced by the pretreatment conditions. In this case, an increase in the reduction temperature led to higher electron density on Pt, altering its chemisorptive properties, weakening the Pt-CO bonds, and increasing its activity for the oxidation of CO. The in situ FTIR data suggest that both the terminal and bridging CO species adsorbed on fully reduced Pt are active for this reaction. The high activity of Pt/TiO2 for the oxidation of CO can also be attributed to the ability of TiO2 to provide or stabilize highly reactive oxygen species at the metal-support interface. However, such species appear to be more reactive toward H{sub 2} than CO. Consequently, Pt/TiO{sub 2} shows substantially lower selectivities toward CO oxidation under PROX conditions than Pt/{gamma}-Al{sub 2}O{sub 3}.

Alexeev,O.; Chin, S.; Engelhard, M.; Ortiz-Soto, L.; Amiridis, M.

2005-01-01T23:59:59.000Z

405

Production of renewable jet fuel range alkanes and commodity chemicals from integrated catalytic  

E-Print Network [OSTI]

and techno-economic analysis of a catalytic process for the conversion of whole biomass into drop-in aviation processing of biomass Jesse Q. Bond,a Aniruddha A. Upadhye,b Hakan Olcay,c Geoffrey A. Tompsett,d Jungho Jae fuels with maximal carbon yields. The combined research areas highlighted include biomass pretreatment

California at Riverside, University of

406

ENGINEERING SCALE UP OF RENEWABLE HYDROGEN PRODUCTION BY CATALYTIC STEAM REFORMING OF PEANUT  

E-Print Network [OSTI]

ENGINEERING SCALE UP OF RENEWABLE HYDROGEN PRODUCTION BY CATALYTIC STEAM REFORMING OF PEANUT SHELLS, and academic organizations is developing a steam reforming process to be demonstrated on the gaseous byproducts of this engineering demonstration project. After an initial problem with the heaters that required modification

407

Catalytic study of SOFC electrode materials in engine exhaust gas Pauline Briaulta  

E-Print Network [OSTI]

1 Catalytic study of SOFC electrode materials in engine exhaust gas atmosphere Pauline Briaulta. An innovative application of this system would be to recover energy from exhaust gas of a thermal engine in a mixture of hydrocarbons (propane, propene), oxygen, carbon monoxide, carbon dioxide, hydrogen and water

Paris-Sud XI, Université de

408

Coating of a stainless steel tube-wall catalytic reactor with thermally treated polysiloxane thick films  

E-Print Network [OSTI]

Coating of a stainless steel tube-wall catalytic reactor with thermally treated polysiloxane thick stainless steel by plasma assisted chemical vapour deposition process. Thicknesses up to 10µm were developed glass-like silicon oxide but cannot be related to an amorphous silica structure. At 1273K the steel

Paris-Sud XI, Université de

409

Comparison of the Catalytic Oxidation Reaction on Graphene Oxide and Reduced Graphene Oxide  

E-Print Network [OSTI]

Comparison of the Catalytic Oxidation Reaction on Graphene Oxide and Reduced Graphene Oxide Laboratory (PAL), Pohang 790-784, Republic of Korea ABSTRACT: The capacities of graphene oxide (GO) and reduced graphene oxide (rGO) films grown on silicon substrate to cause the aniline to azobenzene oxidation

Kim, Sehun

410

Acidity and catalytic activity of zeolite catalysts bound with silica and alumina  

E-Print Network [OSTI]

. Micropore surface area and micropore volume are reduced by about 19% and 18%, respectively, indicating some micropores of ZSM-5 are blocked on binding with silica. SiO2-bound ZSM-5 catalysts have less catalytic activity for butane transformation (cracking...

Wu, Xianchun

2004-09-30T23:59:59.000Z

411

Catalytically Assisted Self-Propagating High-Temperature Synthesis of Tantalum Carbide Powders  

E-Print Network [OSTI]

Catalytically Assisted Self-Propagating High-Temperature Synthesis of Tantalum Carbide Powders Troy high-temperature combustion synthesis (SHS) of materials has gained recognition for its energy in the context of gas-phase and solid-phase transport models. I. Introduction IN RECENT years, self-propagating

Wooldridge, Margaret S.

412

==================== !"#$%&'()*+,-+./,0)12 Development of Micro Ejector for Butane Catalytic Combustor  

E-Print Network [OSTI]

pumps ambient air to the combustion chamber by utilizing the vapor pressure of liquified fuel. Catalytic with the excessive heat of the exhaust gas. The advantage of using ejector is that air-entrainment is achieved without an additional air container or a micro pump, and thus the system should be simple, safe

Kasagi, Nobuhide

413

Prediction of catalytic residues in proteins using machine-learning techniques  

E-Print Network [OSTI]

Prediction of catalytic residues in proteins using machine-learning techniques Natalia V. Petrova) and prediction of protein function using various properties of proteins and amino acids (2). Prediction of the functional residues is a challenging and interesting task. The results of such prediction could

414

Catalytic conversion of glycerol to oxygenated fuel additive in a continuous flow reactor: Process optimization  

E-Print Network [OSTI]

Catalytic conversion of glycerol to oxygenated fuel additive in a continuous flow reactor: Process optimization Malaya R. Nanda a , Zhongshun Yuan a , Wensheng Qin b , Hassan S. Ghaziaskar c , Marc for synthesis of solketal from glycerol was optimized. A maximum yield of 94 ± 2% was obtained at optimum

Qin, Wensheng

415

Hybrid QM/MM Car-Parrinello Simulations of Catalytic and Enzymatic Reactions  

E-Print Network [OSTI]

1 Hybrid QM/MM Car-Parrinello Simulations of Catalytic and Enzymatic Reactions MariaCarola Colombo, we review some recent applications of hybrid Car-Parrinello simulations of chemical and biological recently developed a combination of these two techniques into a hybrid QM/MM Car-Parrinello scheme [4

Guidoni, Leonardo

416

Catalytic Oxidation of Alcohol via Nickel Phosphine Complexes with Pendant Amines  

SciTech Connect (OSTI)

Nickel complexes were prepared with diphosphine ligands that contain pendant amines, and these complexes catalytically oxidize primary and secondary alcohols to their respective aldehydes and ketones. Kinetic and mechanistic studies of these prospective electrocatalysts were performed to understand what influences the catalytic activity. For the oxidation of diphenylmethanol, the catalytic rates were determined to be dependent on the concentration of both the catalyst and the alcohol. The catalytic rates were found to be independent of the concentration of base and oxidant. The incorporation of pendant amines to the phosphine ligand results in substantial increases in the rate of alcohol oxidation with more electron-donating substituents on the pendant amine exhibiting the fastest rates. We thank Dr. John C. Linehan, Dr. Elliott B. Hulley, Dr. Jonathan M. Darmon, and Dr. Elizabeth L. Tyson for helpful discussions. Research by CJW, PD, DLM, and AMA was supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Research by MLH was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle.

Weiss, Charles J.; Das, Partha Pratim; Higgins, Deanna LM; Helm, Monte L.; Appel, Aaron M.

2014-09-05T23:59:59.000Z

417

Functionalized Graphene as a Catalytic Counter Electrode in Dye-Sensitized  

E-Print Network [OSTI]

Functionalized Graphene as a Catalytic Counter Electrode in Dye-Sensitized Solar Cells Joseph D.1021/nn1016428 © 2010 American Chemical Society ABSTRACT When applied on the counter electrode of a dye-sensitized and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States D ye-sensitized

Aksay, Ilhan A.

418

in: Nanotechnology 7(1), pp. 307314, 1996 Emergent Computation by Catalytic Reactions  

E-Print Network [OSTI]

in: Nanotechnology 7(1), pp. 307­314, 1996 Emergent Computation by Catalytic Reactions Wolfgang the idea behind the chemical computational metaphor and outline its relevance for nanotechnology. We set up within this context. The implications of this approach for nanotechnology, parallel computers based on mo

Dittrich, Peter

419

Catalytic Nanoparticle Additives in the Combustion of AP/HTPB Composite Solid Propellant  

E-Print Network [OSTI]

Presented in this thesis is a study of the effects of nano-sized particles used as a catalytic additive in composite solid propellant. This study was done with titanium oxide (titania)-based particles, but much of the findings and theory...

Kreitz, Kevin R.

2012-02-14T23:59:59.000Z

420

Stability of Multiple Steady States of Catalytic Combustion , and J. BRINDLEY  

E-Print Network [OSTI]

3 ) Cpr Initial concentration of propane (mol m 3 ) cp Specific heat capacity (gas) (J kg 1 ) cpcStability of Multiple Steady States of Catalytic Combustion A. JAMES* , and J. BRINDLEY Department state exists involving incomplete combustion of the fuel. The existence of such a stable state, which

James, Alex

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

High Performance Plasma Sputtered Fuel Cell Electrodes with Ultra Low catalytic metal Loadings  

E-Print Network [OSTI]

to be reached between 2010 and 2015 are clear: the catalyst of a fuel cell can cost no more than 4 per kilowatt1 High Performance Plasma Sputtered Fuel Cell Electrodes with Ultra Low catalytic metal Loadings C in plasma fuel cell deposition devices. Pt loadings lower than 0.01 mg cm-2 have been realized. The Pt

Paris-Sud XI, Université de

422

Exoelectrogenic Biofilm as a Template for Sustainable Formation of a Catalytic  

E-Print Network [OSTI]

the electrochemically plated control electrode, even though 30% less Pd was present in the biotemplated catalyst was used as a sustainable template to form mesoporous Pd structures while eliminating the need formation, producing a catalytic Pd mesoporous (pore size 9.7 Æ 0.1 nm) structure attached to the graphite

423

ADAR Proteins: Structure and Catalytic Rena A. Goodman, Mark R. Macbeth and Peter A. Beal  

E-Print Network [OSTI]

ADAR Proteins: Structure and Catalytic Mechanism Rena A. Goodman, Mark R. Macbeth and Peter A. Beal .................................................. 3 R. A. Goodman Á P. A. Beal (&) Department of Chemistry, University of California, One Shields Ave, Davis, CA 95616, USA e-mail: beal@chem.ucdavis.edu M. R. Macbeth (&) Department of Biological Sciences

Beal, Peter A.

424

Catalysts for the selective oxidation of hydrogen sulfide to sulfur  

DOE Patents [OSTI]

This invention provides catalysts for the oxidation of hydrogen sulfide. In particular, the invention provides catalysts for the partial oxidation of hydrogen sulfide to elemental sulfur and water. The catalytically active component of the catalyst comprises a mixture of metal oxides containing titanium oxide and one or more metal oxides which can be selected from the group of metal oxides or mixtures of metal oxides of transition metals or lanthanide metals. Preferred metal oxides for combination with TiO.sub.2 in the catalysts of this invention include oxides of V, Cr, Mn, Fe, Co, Ni, Cu, Nb, Mo, Tc, Ru, Rh, Hf, Ta, W, Au, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. Catalysts which comprise a homogeneous mixture of titanium oxide and niobium (Nb) oxide are also provided. A preferred method for preparing the precursor homogenous mixture of metal hydroxides is by coprecipitation of titanium hydroxide with one or more other selected metal hydroxides. Catalysts of this invention have improved activity and/or selectivity for elemental sulfur production. Further improvements of activity and/or selectivity can be obtained by introducing relatively low amounts (up to about 5 mol %)of a promoter metal oxide (preferably of metals other than titanium and that of the selected second metal oxide) into the homogeneous metal/titanium oxide catalysts of this invention.

Srinivas, Girish (Thornton, CO); Bai, Chuansheng (Baton Rouge, LA)

2000-08-08T23:59:59.000Z

425

Catalytic cracking of a Gippsland reduced crude on zeolite catalysts  

SciTech Connect (OSTI)

Cracking reactions of a Gippsland reduced crude have been investigated at 520[degrees]C over HY and HZSM-5. Gasolines with similar characteristics can be obtained on both zeolites, although the mechanistic routes to these products are quite distinct. Changes in aromatic product selectivities are consistent with the zeolite pore geometries. Minor quantities of aromatics are formed via hydrogen transfer processes involving product olefins and naphthenes over the faujasite and the cyclization (and to a lesser extent oligomerization) of olefinic species on the pentasil. Dehydrogenation of naphthenic species in the feedstock is also important for aromatic formation. While paraffins are formed via hydrogen transfer processes together with cracking and isomerization of feed paraffins on HY, only the latter route can explain formation of saturated species on HZSM-5. The removal of linear paraffins from the GRC was traced as a function of conversion on HY. It was found that the relative reactivity of the linear paraffins increased monotonically with paraffin chain length. 43 refs., 11 figs., 8 tabs.

Guerzoni, F.N.; Abbot, J. (Univ. of Tasmania (Australia))

1994-06-01T23:59:59.000Z

426

A numerical study of geometry dependent errors in velocity, temperature, and density measurements from single grid planar retarding potential analyzers  

SciTech Connect (OSTI)

Planar retarding potential analyzers (RPAs) have been utilized numerous times on high profile missions such as the Communications/Navigation Outage Forecast System and the Defense Meteorological Satellite Program to measure plasma composition, temperature, density, and the velocity component perpendicular to the plane of the instrument aperture. These instruments use biased grids to approximate ideal biased planes. These grids introduce perturbations in the electric potential distribution inside the instrument and when unaccounted for cause errors in the measured plasma parameters. Traditionally, the grids utilized in RPAs have been made of fine wires woven into a mesh. Previous studies on the errors caused by grids in RPAs have approximated woven grids with a truly flat grid. Using a commercial ion optics software package, errors in inferred parameters caused by both woven and flat grids are examined. A flat grid geometry shows the smallest temperature and density errors, while the double thick flat grid displays minimal errors for velocities over the temperature and velocity range used. Wire thickness along the dominant flow direction is found to be a critical design parameter in regard to errors in all three inferred plasma parameters. The results shown for each case provide valuable design guidelines for future RPA development.

Davidson, R. L.; Earle, G. D.; Heelis, R. A. [William B. Hanson Center for Space Sciences, University of Texas at Dallas, 800 W. Campbell Road, WT15, Richardson, Texas 75080 (United States); Klenzing, J. H. [Space Weather Laboratory/Code 674, Goddard Space Flight Center, Greenbelt, Maryland 20771 (United States)

2010-08-15T23:59:59.000Z

427

SOURCE SELECTION INFORMATION -  

Office of Environmental Management (EM)

on Energy and Water Development U.S. House of Representatives The Honorable Lamar Alexander Ranking Member SOURCE SELECTION INFORMATION - SEE FEDERAL ACQUISITION...

428

SOURCE SELECTION INFORMATION -  

Energy Savers [EERE]

on Energy and Water Development U.S. House of Representatives The Honorable Lamar Alexander SOURCE SELECTION INFORMATION - SEE FEDERAL ACQUISITION REGULATION (FAR)...

429

Frequency selective infrared sensors  

SciTech Connect (OSTI)

A frequency selective infrared (IR) photodetector having a predetermined frequency band. The exemplary frequency selective photodetector includes: a dielectric IR absorber having a first surface and a second surface substantially parallel to the first surface; an electrode electrically coupled to the first surface of the dielectric IR absorber; and a frequency selective surface plasmonic (FSSP) structure formed on the second surface of the dielectric IR absorber. The FSSP structure is designed to selectively transmit radiation in the predetermined frequency band that is incident on the FSSP structure substantially independent of the angle of incidence of the incident radiation on the FSSP structure.

Davids, Paul; Peters, David W

2014-11-25T23:59:59.000Z

430

Frequency selective infrared sensors  

DOE Patents [OSTI]

A frequency selective infrared (IR) photodetector having a predetermined frequency band. The exemplary frequency selective photodetector includes: a dielectric IR absorber having a first surface and a second surface substantially parallel to the first surface; an electrode electrically coupled to the first surface of the dielectric IR absorber; and a frequency selective surface plasmonic (FSSP) structure formed on the second surface of the dielectric IR absorber. The FSSP structure is designed to selectively transmit radiation in the predetermined frequency band that is incident on the FSSP structure substantially independent of the angle of incidence of the incident radiation on the FSSP structure.

Davids, Paul; Peters, David W

2013-05-28T23:59:59.000Z

431

Principles of water oxidation and O2-based hydrocarbon transformation by multinuclear catalytic sites  

SciTech Connect (OSTI)

Abstract The central thrust of this integrated experimental and computational research program was to obtain an atomistic-level understanding of the structural and dynamic factors underlying the design of catalysts for water oxidation and selective reductant-free O2-based transformations. The focus was on oxidatively robust polyoxometalate (POM) complexes in which a catalytic active site interacts with proximal metal centers in a synergistic manner. Thirty five publications in high-impact journals arose from this grant. I. Developing an oxidatively and hydrolytically stable and fast water oxidation catalyst (WOC), a central need in the production of green fuels using water as a reductant, has proven particularly challenging. During this grant period we have designed and investigated several carbon-free, molecular (homogenous), oxidatively and hydrolytically stable WOCs, including the Rb8K2[{Ru4O4(OH)2(H2O)4}(?-SiW10O36)2]·25H2O (1) and [Co4(H2O)2(?-PW9O34)2]10- (2). Although complex 1 is fast, oxidatively and hydrolytically stable WOC, Ru is neither abundant nor inexpensive. Therefore, development of a stable and fast carbon-free homogenous WOC, based on earth-abundant elements became our highest priority. In 2010, we reported the first such catalyst, complex 2. This complex is substantially faster than 1 and stable under homogeneous conditions. Recently, we have extended our efforts and reported a V2-analog of the complex 2, i.e. [Co4(H2O)2(?-VW9O34)2]10- (3), which shows an even greater stability and reactivity. We succeeded in: (a) immobilizing catalysts 1 and 2 on the surface of various electrodes, and (b) elucidating the mechanism of O2 formation and release from complex 1, as well as the Mn4O4L6 “cubane” cluster. We have shown that the direct O-O bond formation is the most likely pathway for O2 formation during water oxidation catalyzed by 1. II. Oxo transfer catalysts that contain two proximal and synergistically interacting redox active metal centers in the active site form another part of considerable interest of our grant because species with such sites [including methane monooxygenase (MMO) and more] are some of the most effective oxygenase catalysts known. Our team conducted the following research on ?-M2-Keggin complexes: (a) investigated stability of the trimer [{Fe3(OH)3(H2O)2}3(?-SiW10O36)3]15-, 4, in water, and developed the chemistry and catalysis of the di-iron centered POM, [?(1,2)-SiW10{Fe(OH)}2O38]6-, 5, in organic solvents (Figure 2). We also study the thermodynamic and structural stability of ?-M2-Keggin in aqueous media for different M’s (d-electron metals). We have defined two structural classes of POMs with proximally bound d-electron metal centers. We refer to these structural isomers of the {?-M2SiW10} family of POMs as “in-pocket” and “out-of pocket”. We have elucidated the factors controlling the structure and stability of the V, Fe, Ru, Tc, Mo and Rh derivatives of [(SiO4)M2(OH)2W10O32]4- using a range of computational tools. We have: (a) demonstrated that heteroatom X in these polyanions may function as an “internal switch” for defining the ground electronic states and, consequently, the reactivity of the ?-M2-Keggin POM complexes; (b) elucidated reactivity of divacant lacunary species and polyperoxotungstates (PPTs), {Xn+O4[WO(O2)2]4}n-, which could be degradation products of ?-M2-Keggin complexes in aqueous media; (c) elucidated the role of the POM ligand in stabilization of {Ru2} and {(Ru-oxo)2} fragments in the reactant and product of the reaction of {?-[(Xn+O4)Ru2(OH)2W10O32]}(8-n)- (where X = Si4+, P5+ and S6+) with O2, and (d) the mechanisms of olefin epoxidation catalyzed by these di-d-transition metal substituted and divacant lacunary ?-M2-Keggin complexes. III. Complementing the efforts presented above was the development of less time-consuming but reasonably accurate computational methods allowing one to explore more deeply large catalytic systems. We developed Reactive Force Field (ReaxFF) to study interaction of the targeted POMs with water, pro

Musaev, Djamaladdin G [Chemistry, Emory University; Hill, Craig L [Chemistry, Emory University; Morokuma, Keiji [Chemistry, Emory University

2014-10-28T23:59:59.000Z

432

SELECTING INFORMATION TECHNOLOGY SECURITY  

E-Print Network [OSTI]

be selected and used within the organization's overall program to man age the design, development, and maintenance of its IT security infra structure, and to protect the confiden tiality, integrity objectives and to protect information. Guide to Selecting Information Technology Security Products NIST

433

Turing structures in catalytic surface reactions; The facetting of Pt(110) in Co + O sub 2  

SciTech Connect (OSTI)

This paper reports that exposing a Pt(110) surface to catalytic CO oxidation causes the development of a regular facet pattern of microscopic dimensions which has been identified as a dissipative structure of the Turing type. The primary step in the facetting process is considered to be the 1 {times} 1 {r reversible} 1 {times} 2 phase transition which is also responsible for the occurrence of kinetic oscillations in the same system. This interpretation was confirmed in a Monte Carlo simulation which was based on the Langmuir-Hinshelwood mechanism of catalytic CO oxidation and the properties of the surface phase transition. Thus a detailed microscopic description is available for the process by which a Turing structure is formed during a surface reaction.

Imbihl, R. (Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin (Germany))

1992-04-20T23:59:59.000Z

434

Catalytic igniters and their use to ignite lean hydrogen-air mixtures  

DOE Patents [OSTI]

A catalytic igniter which can ignite a hydrogen-air mixture as lean as 5.5% hydrogen with induction times ranging from 20 s to 400 s, under conditions which may be present during a loss-of-liquid-coolant accident at a light water nuclear reactor comprises (a) a perforate catalytically active substrate, such as a platinum coated ceramic honeycomb or wire mesh screen, through which heated gases produced by oxidation of the mixture can freely flow and (b) a plurality of thin platinum wires mounted in a thermally conductive manner on the substrate and positioned thereon so as to be able to receive heat from the substrate and the heated gases while also in contact with unoxidized gases.

McLean, William J. (Oakland, CA); Thorne, Lawrence R. (Livermore, CA); Volponi, Joanne V. (Livermore, CA)

1988-01-01T23:59:59.000Z

435

Electro-catalytic oxidation device for removing carbon from a fuel reformate  

DOE Patents [OSTI]

An electro-catalytic oxidation device (ECOD) for the removal of contaminates, preferably carbonaceous materials, from an influent comprising an ECOD anode, an ECOD cathode, and an ECOD electrolyte. The ECOD anode is at a temperature whereby the contaminate collects on the surface of the ECOD anode as a buildup. The ECOD anode is electrically connected to the ECOD cathode, which consumes the buildup producing electricity and carbon dioxide. The ECOD anode is porous and chemically active to the electro-catalytic oxidation of the contaminate. The ECOD cathode is exposed to oxygen, and made of a material which promotes the electro-chemical reduction of oxygen to oxidized ions. The ECOD electrolyte is non-permeable to gas, electrically insulating and a conductor to oxidized. The ECOD anode is connected to the fuel reformer and the fuel cell. The ECOD electrolyte is between and in ionic contact with the ECOD anode and the ECOD cathode.

Liu, Di-Jia (Naperville, IL)

2010-02-23T23:59:59.000Z

436

Catalytic two-stage coal liquefaction process having improved nitrogen removal  

DOE Patents [OSTI]

A process for catalytic multi-stage hydrogenation and liquefaction of coal to produce high yields of low-boiling hydrocarbon liquids containing low concentrations of nitogen compounds. First stage catalytic reaction conditions are 700.degree.-800.degree. F. temperature, 1500-3500 psig hydrogen partial pressure, with the space velocity maintained in a critical range of 10-40 lb coal/hr ft.sup.3 catalyst settled volume. The first stage catalyst has 0.3-1.2 cc/gm total pore volume with at least 25% of the pore volume in pores having diameters of 200-2000 Angstroms. Second stage reaction conditions are 760.degree.-870.degree. F. temperature with space velocity exceeding that in the first stage reactor, so as to achieve increased hydrogenation yield of low-boiling hydrocarbon liquid products having at least 75% removal of nitrogen compounds from the coal-derived liquid products.

Comolli, Alfred G. (Yardley, PA)

1991-01-01T23:59:59.000Z

437

Incorporation of catalytic dehydrogenation into fischer-tropsch synthesis to significantly reduce carbon dioxide emissions  

DOE Patents [OSTI]

A new method of producing liquid transportation fuels from coal and other hydrocarbons that significantly reduces carbon dioxide emissions by combining Fischer-Tropsch synthesis with catalytic dehydrogenation is claimed. Catalytic dehydrogenation (CDH) of the gaseous products (C1-C4) of Fischer-Tropsch synthesis (FTS) can produce large quantities of hydrogen while converting the carbon to multi-walled carbon nanotubes (MWCNT). Incorporation of CDH into a FTS-CDH plant converting coal to liquid fuels can eliminate all or most of the CO.sub.2 emissions from the water-gas shift (WGS) reaction that is currently used to elevate the H.sub.2 level of coal-derived syngas for FTS. Additionally, the FTS-CDH process saves large amounts of water used by the WGS reaction and produces a valuable by-product, MWCNT.

Huffman, Gerald P.

2012-11-13T23:59:59.000Z

438

Low density microcellular carbon or catalytically impregnated carbon foams and process for their preparation  

DOE Patents [OSTI]

Machinable and structurally stable, low density microcellular carbon, and catalytically impregnated carbon, foams, and process for their preparation, are provided. Pulverized sodium chloride is classified to improve particle size uniformity, and the classified particles may be further mixed with a catalyst material. The particles are cold pressed into a compact having internal pores, and then sintered. The sintered compact is immersed and then submerged in a phenolic polymer solution to uniformly fill the pores of the compact with phenolic polymer. The compact is then heated to pyrolyze the phenolic polymer into carbon in the form of a foam. Then the sodium chloride of the compact is leached away with water, and the remaining product is freeze dried to provide the carbon, or catalytically impregnated carbon, foam.

Hooper, R.W.; Pekala, R.W.

1987-04-30T23:59:59.000Z

439

Experimental and numerical study of the behavior of three-way catalytic converters under different engine operation conditions  

E-Print Network [OSTI]

The thesis reports the studies on how the three-way catalytic converters behave under different operation conditions. The main focus of the work is in the oxygen storage capacity of the three-way catalyst. Rich-to-lean ...

Zhang, Yuetao

2005-01-01T23:59:59.000Z

440

Effects of boundaries on pattern formation: Catalytic oxidation of CO on platinum  

SciTech Connect (OSTI)

The effect of boundaries on pattern formation was studied for the catalytic oxidation of carbon monoxide on platinum surfaces. Photolithography was used to create microscopic reacting domains on polycrystalline foils and single-crystal platinum (110) surfaces with inert titanium overlayers. Certain domain geometries give rise to patterns that have not been observed on the untreated catalyst and bring to light surface mechanisms that have no analog in homogeneous reaction-diffusion systems.

Graham, M.D. (Univ. of Wisconsin, Madison (United States)); Kevrekidis, I.G. (Princeton Univ., NJ (United States)); Asakura, K.; Lauterbach, J.; Krischer, K.; Rotermund, H.H.; Ertl, G. (Fritz-Haber-Institut de Max-Planck-Gesellschaft, Berlin (Germany))

1994-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Nanorods, nanospheres, nanocubes: Synthesis, characterization and catalytic activity of nanoferrites of Mn, Co, Ni, Part-89  

SciTech Connect (OSTI)

Graphical abstract: Prepared nanoferrites were characterized by FE-SEM and bright field TEM micrographs. The catalytic effect of these nanoferrites was evaluated on the thermal decomposition of ammonium perchlorate using TG and TG–DSC techniques. The kinetics of thermal decomposition of AP was evaluated using isothermal TG data by model fitting as well as isoconversional method. Display Omitted Highlights: ? Synthesis of ferrite nanostructures (?20.0 nm) by wet-chemical method under different synthetic conditions. ? Characterization using XRD, FE-SEM, EDS, TEM, HRTEM and SAED pattern. ? Catalytic activity of ferrite nanostructures on AP thermal decomposition by thermal techniques. ? Burning rate measurements of CSPs with ferrite nanostructures. ? Kinetics of thermal decomposition of AP + nanoferrites. -- Abstract: In this paper, the nanoferrites of Mn, Co and Ni were synthesized by wet chemical method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive, X-ray spectra (EDS), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HR-TEM). It is catalytic activity were investigated on the thermal decomposition of ammonium perchlorate (AP) and composite solid propellants (CSPs) using thermogravimetry (TG), TG coupled with differential scanning calorimetry (TG–DSC) and ignition delay measurements. Kinetics of thermal decomposition of AP + nanoferrites have also been investigated using isoconversional and model fitting approaches which have been applied to data for isothermal TG decomposition. The burning rate of CSPs was considerably enhanced by these nanoferrites. Addition of nanoferrites to AP led to shifting of the high temperature decomposition peak toward lower temperature. All these studies reveal that ferrite nanorods show the best catalytic activity superior to that of nanospheres and nanocubes.

Singh, Supriya; Srivastava, Pratibha [Department of Chemistry, D.D.U. Gorakhpur University, Gorakhpur 273009 (India)] [Department of Chemistry, D.D.U. Gorakhpur University, Gorakhpur 273009 (India); Singh, Gurdip, E-mail: gsingh4us@yahoo.com [Department of Chemistry, D.D.U. Gorakhpur University, Gorakhpur 273009 (India)] [Department of Chemistry, D.D.U. Gorakhpur University, Gorakhpur 273009 (India)

2013-02-15T23:59:59.000Z

442

Reduction of nitrogen oxides with catalytic acid resistant aluminosilicate molecular sieves and ammonia  

DOE Patents [OSTI]

Noxious nitrogen oxides in a waste gas stream such as the stack gas from a fossil-fuel-fired power generation plant or other industrial plant off-gas stream is catalytically reduced to elemental nitrogen and/or innocuous nitrogen oxides employing ammonia as reductant in the presence of a zeolite catalyst in the hydrogen or sodium form having pore openings of about 3 to 10 A.

Pence, Dallas T. (Idaho Falls, ID); Thomas, Thomas R. (Idaho Falls, ID)

1980-01-01T23:59:59.000Z

443

Informatics guided discovery of surface structure-chemistry relationships in catalytic nanoparticles  

SciTech Connect (OSTI)

A data driven discovery strategy based on statistical learning principles is used to discover new correlations between electronic structure and catalytic activity of metal surfaces. From the quantitative formulations derived from this informatics based model, a high throughput computational framework for predicting binding energy as a function of surface chemistry and adsorption configuration that bypasses the need for repeated electronic structure calculations has been developed.

Andriotis, Antonis N., E-mail: andriot@iesl.forth.gr [Institute of Electronic Structure and Laser, FORTH, P.O. Box 1527, 71110 Heraklio, Crete (Greece); Mpourmpakis, Giannis, E-mail: gmpourmp@pitt.edu [Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15621 (United States)] [Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15621 (United States); Broderick, Scott, E-mail: broderick.scott@gmail.com; Rajan, Krishna, E-mail: krajan@iastate.edu [Materials Science and Engineering, Iowa State University, Ames, Iowa 50011 (United States)] [Materials Science and Engineering, Iowa State University, Ames, Iowa 50011 (United States); Datta, Somnath, E-mail: somnath.datta@louisville.edu [Department of Bioinformatics and Biostatistics, University of Louisville, Louisville, Kentucky 40202 (United States)] [Department of Bioinformatics and Biostatistics, University of Louisville, Louisville, Kentucky 40202 (United States); Sunkara, Mahendra, E-mail: mahendra@louisville.edu [Department of Chemical Engineering, University of Louisville, Louisville, Kentucky 40202 (United States)] [Department of Chemical Engineering, University of Louisville, Louisville, Kentucky 40202 (United States); Menon, Madhu, E-mail: super250@uky.edu [Department of Physics and Astronomy and Center for Computational Sciences, University of Kentucky, Lexington, Kentucky 40506 (United States)] [Department of Physics and Astronomy and Center for Computational Sciences, University of Kentucky, Lexington, Kentucky 40506 (United States)

2014-03-07T23:59:59.000Z

444

Effect of thermal treatment on coke reactivity and catalytic iron mineralogy  

SciTech Connect (OSTI)

Iron minerals in coke can catalyze its gasification and may affect coke behavior in the blast furnace. The catalytic behavior of iron depends largely upon the nature of the iron-bearing minerals. To determine the mineralogical changes that iron could undergo in the blast furnace, cokes made from three coals containing iron present in different mineral forms (clays, carbonates, and pyrite) were examined. All coke samples were heat-treated in a horizontal furnace at 1373, 1573, and 1773 K and then gasified with CO{sub 2} at 1173 K in a fixed bed reactor (FBR). Coke mineralogy was characterized using quantitative X-ray diffraction (XRD) analysis of coke mineral matter prepared by low-temperature ashing (LTA) and field emission scanning electron microscopy combined with energy dispersive X-ray analysis (FESEM/EDS). The mineralogy of the three cokes was most notably distinguished by differing proportions of iron-bearing phases. During heat treatment and subsequent gasification, iron-containing minerals transformed to a range of minerals but predominantly iron-silicides and iron oxides, the relative amounts of which varied with heat treatment temperature and gasification conditions. The relationship between initial apparent reaction rate and the amount of catalytic iron minerals - pyrrhotite, metallic iron, and iron oxides - was linear and independent of heat treatment temperature at total catalyst levels below 1 wt %. The study showed that the coke reactivity decreased with increasing temperature of heat treatment due to decreased levels of catalytic iron minerals (largely due to formation of iron silicides) as well as increased ordering of the carbon structure. The study also showed that the importance of catalytic mineral matter in determining reactivity declines as gasification proceeds. 37 refs., 13 figs., 7 tabs.

Byong-chul Kim; Sushil Gupta; David French; Richard Sakurovs; Veena Sahajwalla [University of New South Wales, Sydney, NSW (Australia). Centre for Sustainable Materials Research and Technology

2009-07-15T23:59:59.000Z

445

Spectroscopic and Kinetic Investigation of the Catalytic Mechanism of Tyrosine Hydroxylase  

E-Print Network [OSTI]

into the catalytic mechanism of this physiologically important enzyme. Analysis of the TyrH reaction by rapid freeze-quench M?ssbauer spectroscopy allowed the first direct characterization of an Fe(IV) intermediate in a mononuclear non- heme enzyme catalyzing... aromatic hydroxylation. Further rapid kinetic studies established the kinetic competency of this intermediate to be the long-postulated hydroxylating species, Fe(IV)O. Spectroscopic investigations of wild-type (WT) and mutant TyrH complexes using...

Eser, Bekir Engin

2011-02-22T23:59:59.000Z

446

Temperature-dependent oxygen release, intercalation behaviour and catalytic properties of V{sub 2}O{sub 5}.xNb{sub 2}O{sub 5} compounds  

SciTech Connect (OSTI)

Graphical abstract: Temperature dependent oxygen loss and uptake of V{sub 2,38}Nb{sub 10,7}O{sub 32,7} in N{sub 2} (p(O{sub 2}) = 4 x 10{sup -5} bar) and IR spectra of gas mixtures after the reactor with V{sub 2,38}Nb{sub 10,7}O{sub 32,7} (A = 16.1 m{sup 2}/g) and propane. Highlights: {yields} V{sub 2}O{sub 5}.xNb{sub 2}O{sub 5} complex oxide compounds as catalysts. {yields} The (V, Nb){sub 2}O{sub 5} phases are able to a reversible release and uptake of oxygen without a structural variation. {yields} Metastable (V, Nb){sub 2}O{sub 5} phases are able to catalyse the oxidative dehydrogenation of propane and propene. {yields} Thermodynamically stable VNb{sub 9}O{sub 25} phase shows no measurable catalytic activity. -- Abstract: In order to investigate the catalytic properties, V{sub 2,38}Nb{sub 10,7}O{sub 32,7}, VNb{sub 9}O{sub 25} and solid solutions of V{sub 2}O{sub 5} in TT-Nb{sub 2}O{sub 5} were prepared by thermal decomposition of freeze-dried oxalate precursors. The samples were characterised by X-ray diffraction and surface area determination. The crystalline samples are capable of the intercalation of sodium and lithium ions from solution. Above a temperature of about 500 {sup o}C, in dependence on the oxygen partial pressure a reversible release and uptake of oxygen without a structural variation takes place. The catalytic properties have been evaluated for the oxidative dehydrogenation (ODH) of propane and propene. There are only small differences in the catalytic activity of the different crystalline samples. Because of the relative high starting temperature, a selective catalytic oxidation of propane to propene is hardly observed.

Boerrnert, Carina [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Str. 40, D-01187 Dresden (Germany)] [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Str. 40, D-01187 Dresden (Germany); Zosel, Jens [Kurt-Schwabe-Institut fuer Mess- und Sensortechnik e. V. Meinsberg, Kurt-Schwabe-Str. 4, D-04720 Ziegra-Knobelsdorf (Germany)] [Kurt-Schwabe-Institut fuer Mess- und Sensortechnik e. V. Meinsberg, Kurt-Schwabe-Str. 4, D-04720 Ziegra-Knobelsdorf (Germany); Polte, Annette; Wenzel, Roswitha [Fachrichtung Chemie und Lebensmittelchemie, Technische Universitaet Dresden, Helmholtz Str. 10, D-01069 Dresden (Germany)] [Fachrichtung Chemie und Lebensmittelchemie, Technische Universitaet Dresden, Helmholtz Str. 10, D-01069 Dresden (Germany); Guth, Ulrich [Kurt-Schwabe-Institut fuer Mess- und Sensortechnik e. V. Meinsberg, Kurt-Schwabe-Str. 4, D-04720 Ziegra-Knobelsdorf (Germany)] [Kurt-Schwabe-Institut fuer Mess- und Sensortechnik e. V. Meinsberg, Kurt-Schwabe-Str. 4, D-04720 Ziegra-Knobelsdorf (Germany); Langbein, Hubert, E-mail: Hubert.Langbein@chemie.tu-dresden.de [Fachrichtung Chemie und Lebensmittelchemie, Technische Universitaet Dresden, Helmholtz Str. 10, D-01069 Dresden (Germany)] [Fachrichtung Chemie und Lebensmittelchemie, Technische Universitaet Dresden, Helmholtz Str. 10, D-01069 Dresden (Germany)

2011-11-15T23:59:59.000Z

447

Selectable fragmentation warhead  

SciTech Connect (OSTI)

This report discusses a selectable fragmentation warhead which is capable of producing a predetermined number of fragments from a metal plate, and accelerating the fragments toward a target. A first explosive located adjacent to the plate is detonated at selected number of points by laser-driven slapper detonators. In one embodiment, a smoother-disk and a second explosive, located adjacent to the first explosive, serve to increase acceleration of the fragments toward a target. The ability to produce a selected number of fragments allows for effective destruction of a chosen target.

Bryan, C.S.; Paisley, D.L.; Montoya, N.I.; Stahl, D.B.

1992-12-31T23:59:59.000Z

448

Elimination Of Catalytic Hydrogen Generation In Defense Waste Processing Facility Slurries  

SciTech Connect (OSTI)

Based on lab-scale simulations of Defense Waste Processing Facility (DWPF) slurry chemistry, the addition of sodium nitrite and sodium hydroxide to waste slurries at concentrations sufficient to take the aqueous phase into the alkaline region (pH > 7) with approximately 500 mg nitrite ion/kg slurry (assuming <25 wt% total solids, or equivalently 2,000 mg nitrite/kg total solids) is sufficient to effectively deactivate the noble metal catalysts at temperatures between room temperature and boiling. This is a potential strategy for eliminating catalytic hydrogen generation from the list of concerns for sludge carried over into the DWPF Slurry Mix Evaporator Condensate Tank (SMECT) or Recycle Collection Tank (RCT). These conclusions are drawn in large part from the various phases of the DWPF catalytic hydrogen generation program conducted between 2005 and 2009. The findings could apply to various situations, including a solids carry-over from either the Sludge Receipt and Adjustment Tank (SRAT) or Slurry Mix Evaporator (SME) into the SMECT with subsequent transfer to the RCT, as well as a spill of formic acid into the sump system and transfer into an RCT that already contains sludge solids. There are other potential mitigating factors for the SMECT and RCT, since these vessels are typically operated at temperatures close to the minimum temperatures that catalytic hydrogen has been observed to occur in either the SRAT or SME (pure slurry case), and these vessels are also likely to be considerably more dilute in both noble metals and formate ion (the two essential components to catalytic hydrogen generation) than the two primary process vessels. Rhodium certainly, and ruthenium likely, are present as metal-ligand complexes that are favored under certain concentrations of the surrounding species. Therefore, in the SMECT or RCT, where a small volume of SRAT or SME material would be significantly diluted, conditions would be less optimal for forming or sustaining the catalytic ligand species. Such conditions are likely to adversely impact the ability of the transferred mass to produce hydrogen at the same rate (per unit mass SRAT or SME slurry) as in the SRAT or SME vessels.

Koopman, D. C.

2013-01-22T23:59:59.000Z

449

Solar selective absorption coatings  

DOE Patents [OSTI]

A new class of solar selective absorption coatings are disclosed. These coatings comprise a structured metallic overlayer such that the overlayer has a sub-micron structure designed to efficiently absorb solar radiation, while retaining low thermal emissivity for infrared thermal radiation. A sol-gel layer protects the structured metallic overlayer from mechanical, thermal, and environmental degradation. Processes for producing such solar selective absorption coatings are also disclosed.

Mahoney, Alan R. (Albuquerque, NM); Reed, Scott T. (Albuquerque, NM); Ashley, Carol S. (Albuquerque, NM); Martinez, F. Edward (Horseheads, NY)

2003-10-14T23:59:59.000Z

450

Solar selective absorption coatings  

DOE Patents [OSTI]

A new class of solar selective absorption coatings are disclosed. These coatings comprise a structured metallic overlayer such that the overlayer has a sub-micron structure designed to efficiently absorb solar radiation, while retaining low thermal emissivity for infrared thermal radiation. A sol-gel layer protects the structured metallic overlayer from mechanical, thermal, and environmental degradation. Processes for producing such solar selective absorption coatings are also disclosed.

Mahoney, Alan R. (Albuquerque, NM); Reed, Scott T. (Albuquerque, NM); Ashley, Carol S. (Albuquerque, NM); Martinez, F. Edward (Horseheads, NY)

2004-08-31T23:59:59.000Z

451

Spectrally selective glazings  

SciTech Connect (OSTI)

Spectrally selective glazing is window glass that permits some portions of the solar spectrum to enter a building while blocking others. This high-performance glazing admits as much daylight as possible while preventing transmission of as much solar heat as possible. By controlling solar heat gains in summer, preventing loss of interior heat in winter, and allowing occupants to reduce electric lighting use by making maximum use of daylight, spectrally selective glazing significantly reduces building energy consumption and peak demand. Because new spectrally selective glazings can have a virtually clear appearance, they admit more daylight and permit much brighter, more open views to the outside while still providing the solar control of the dark, reflective energy-efficient glass of the past. This Federal Technology Alert provides detailed information and procedures for Federal energy managers to consider spectrally selective glazings. The principle of spectrally selective glazings is explained. Benefits related to energy efficiency and other architectural criteria are delineated. Guidelines are provided for appropriate application of spectrally selective glazing, and step-by-step instructions are given for estimating energy savings. Case studies are also presented to illustrate actual costs and energy savings. Current manufacturers, technology users, and references for further reading are included for users who have questions not fully addressed here.

NONE

1998-08-01T23:59:59.000Z

452

Vanadium oxide based nanostructured materials for catalytic oxidative dehydrogenation of propane : effect of heterometallic centers on the catalyst performance.  

SciTech Connect (OSTI)

Catalytic properties of a series of new class of catalysts materials-[Co{sub 3}(H{sub 2}O){sub 12}V{sub 18}O{sub 42} (XO{sub 4})].24H{sub 2}O (VNM-Co), [Fe{sub 3}(H{sub 2}O){sub 12}V{sub 18}O{sub 42}(XO{sub 4})].24H{sub 2}O (VNM-Fe) (X = V, S) and [H{sub 6}Mn{sub 3}(H{sub 2}O){sub 12}V{sub 18}O{sub 42}(VO{sub 4})].30H{sub 2}O for the oxidative dehydrogenation of propane is studied. The open-framework nanostructures in these novel materials consist of three-dimensional arrays of {l_brace}V{sub 18}O{sub 42}(XO{sub 4}){r_brace} (X = V, S) clusters interconnected by {l_brace}-O-M-O-{r_brace} (M = Mn, Fe, Co) linkers. The effect of change in the heterometallic center M (M = Mn, Co, Fe) of the linkers on the catalyst performance was studied. The catalyst material with Co in the linker showed the best performance in terms of propane conversion and selectivity at 350 C. The material containing Fe was most active but least selective and Mn containing catalyst was least active. The catalysts were characterized by Temperature Programmed Reduction (TPR), BET surface area measurement, Diffuse Reflectance Infrared Fourier Transform Spectroscopy, and X-ray Absorption Spectroscopy. TPR results show that all three catalysts are easily reducible and therefore are active at relatively low temperature. In situ X-ray absorption near edge spectroscopy (XANES) and extended X-ray absorption fine structure spectroscopy (EXAFS) studies revealed that the oxidation state of Co(II) remained unchanged up to 425 C (even after pretreatment). The reduction of Co(II) into metallic form starts at 425 C and this process is completed at 600 C.

Khan, M. I.; Deb, S.; Aydemir, K.; Alwarthan, A. A.; Chattopadhyay, S.; Miller, J. T.; Marshall, C. L. (Chemical Sciences and Engineering Division); (Illinois Inst. of Tech.); (King Saud Univ.)

2010-01-01T23:59:59.000Z

453

Space-charge compensation measurements in electron cyclotron resonance ion source low energy beam transport lines with a retarding field analyzer  

SciTech Connect (OSTI)

In this paper we describe the first systematic measurement of beam neutralization (space charge compensation) in the ECR low energy transport line with a retarding field analyzer, which can be used to measure the potential of the beam. Expected trends for the space charge compensation levels such as increase with residual gas pressure, beam current, and beam density could be observed. However, the overall levels of neutralization are consistently low (<60%). The results and the processes involved for neutralizing ion beams are discussed for conditions typical for ECR injector beam lines. The results are compared to a simple theoretical beam plasma model as well as simulations.

Winklehner, D.; Leitner, D., E-mail: leitnerd@nscl.msu.edu; Cole, D.; Machicoane, G.; Tobos, L. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)] [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

2014-02-15T23:59:59.000Z

454

High Selectivity Oxygen Delignification  

SciTech Connect (OSTI)

Project Objective: The objectives of this project are as follows: (1) Examine the physical and chemical characteristics of a partner mill pre- and post-oxygen delignified pulp and compare them to lab generated oxygen delignified pulps; (2) Apply the chemical selectivity enhancement system to the partner pre-oxygen delignified pulps under mill conditions (with and without any predetermined amounts of carryover) to determine how efficiently viscosity is preserved, how well selectivity is enhanced, if strength is improved, measure any yield differences and/or bleachability differences; and (3) Initiate a mill scale oxygen delignification run using the selectivity enhancement agent, collect the mill data, analyze it, and propose any future plans for implementation.

Lucian A. Lucia

2005-11-15T23:59:59.000Z

455

Selected Topics in Column Generation  

E-Print Network [OSTI]

Dec 2, 2002 ... Page 1. Selected Topics in Column Generation. Marco E. Lübbecke ... is an ever recurring concept in our “selected topics.” OR/MS Subject ...

2002-12-02T23:59:59.000Z

456

Solar selective surfaces  

SciTech Connect (OSTI)

Postformable solar selective coatings are disclosed for use on substrates such as aluminum. The coatings use a finely divided black inherently selective spinel pigment such as Co3O4, CuCr2O4 or CuxCo3-xO4 where X is 0.03 to 0.3 and preferably 0.10 to 0.30. The binders are soluble copolymers of vinylidene fluoride or blends thereof or vinylidene fluoride with a copolymer of methyl methacrylate.

Van Buskirk, O.R.

1982-01-12T23:59:59.000Z

457

Formic Acid Free Flowsheet Development To Eliminate Catalytic Hydrogen Generation In The Defense Waste Processing  

SciTech Connect (OSTI)

The Defense Waste Processing Facility (DWPF) processes legacy nuclear waste generated at the Savannah River Site (SRS) during production of plutonium and tritium demanded by the Cold War. The nuclear waste is first treated via a complex sequence of controlled chemical reactions and then vitrified into a borosilicate glass form and poured into stainless steel canisters. Converting the nuclear waste into borosilicate glass canisters is a safe, effective way to reduce the volume of the waste and stabilize the radionuclides. Testing was initiated to determine whether the elimination of formic acid from the DWPF's chemical processing flowsheet would eliminate catalytic hydrogen generation. Historically, hydrogen is generated in chemical processing of alkaline High Level Waste sludge in DWPF. In current processing, sludge is combined with nitric and formic acid to neutralize the waste, reduce mercury and manganese, destroy nitrite, and modify (thin) the slurry rheology. The noble metal catalyzed formic acid decomposition produces hydrogen and carbon dioxide. Elimination of formic acid by replacement with glycolic acid has the potential to eliminate the production of catalytic hydrogen. Flowsheet testing was performed to develop the nitric-glycolic acid flowsheet as an alternative to the nitric-formic flowsheet currently being processed at the DWPF. This new flowsheet has shown that mercury can be reduced and removed by steam stripping in DWPF with no catalytic hydrogen generation. All processing objectives were also met, including greatly reducing the Slurry Mix Evaporator (SME) product yield stress as compared to the baseline nitric/formic flowsheet. Ten DWPF tests were performed with nonradioactive simulants designed to cover a broad compositional range. No hydrogen was generated in testing without formic acid.

Lambert, Dan P.; Stone, Michael E.; Newell, J. David; Fellinger, Terri L.; Bricker, Jonathan M.

2012-09-14T23:59:59.000Z

458

Final Report: Catalytic Hydrocarbon Reactions over Supported Metal Oxides, August 1, 1995 - July 31, 1999  

SciTech Connect (OSTI)

The research program focused on the catalysis of hydrodesulfurization (HDS) over molybdenum-based catalysts and how catalyst composition, redox ability, structure and neighboring sites control the catalytic properties of metal oxides. We sought to understand the catalytic features/sites that control hydrogenation, hydrogenolysis, and isomerization during HDS. Unprompted silica-supported molybdenum oxides and molybdenum sulfides were studied. Model catalyst systems were prepared from organometallic precursors or cluster compounds to generate supported structures that feature Mo(II) and Mo(IV) cations that are isolated or in ensembles and that have either Mo-O or Mo-S bonds. Conventional MOS{sub 2} catalysts, which contain both edge and rim sites, were be studied. Finally, single-layer MOS{sub 2} structures were also prepared from 2H-MoS{sub 2} powder so that the model systems could be compared against a disulfide catalyst that only involves rim sites. Catalytic reactions for thiophene and tetrahydrothione were studied over the various catalysts. Oxidation states were determined using X-ray photoelectron spectroscopy. X-ray crystallography was used to characterize and follow changes in the MOS{sub 2} structures. The program on metal oxides prepared supported oxides that have a specific structure and oxidation state to serve as model templates for the more complex commercial catalysts and then employed these structures in reaction studies. This focus area examined the relationships between structure and cation redox characteristics in oxidation catalysis. Infrared and Raman spectroscopy were used to characterize the cations and reaction intermediates.

Ekerdt, John G.

1999-07-31T23:59:59.000Z

459

Dendrimer Templated Synthesis of One Nanometer Rh and Pt Particles Supported on Mesoporous Silica: Catalytic Activity for Ethylene and Pyrrole Hydrogenation.  

E-Print Network [OSTI]

Scheme 2) and pyrrole hydrogenation (Scheme 3). Synthesis ofSynthesis of One Nanometer Rh and Pt Particles Supported on Mesoporous Silica: Catalytic Activity for Ethylene and Pyrrole

Huang, Wenyu

2009-01-01T23:59:59.000Z

460

Biofuels from Pyrolysis: Catalytic Biocrude Production in a Novel, Short-Contact Time Reactor  

SciTech Connect (OSTI)

Broad Funding Opportunity Announcement Project: RTI is developing a new pyrolysis process to convert second-generation biomass into biofuels in one simple step. Pyrolysis is the decomposition of substances by heating—the same process used to render wood into charcoal, caramelize sugar, and dry roast coffee and beans. RTI’s catalytic biomass pyrolysis differs from conventional flash pyrolysis in that its end product contains less oxygen, metals, and nitrogen—all of which contribute to corrosion, instability, and inefficiency in the fuel-production process. This technology is expected to easily integrate into the existing domestic petroleum refining infrastructure, making it an economically attractive option for biofuels production.

None

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "retard selective catalytic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Hydrothermal synthesis and catalytic properties of {alpha}- and {beta}-MnO{sub 2} nanorods  

SciTech Connect (OSTI)

One-dimensional {alpha}-MnO{sub 2} and {beta}-MnO{sub 2} single-crystalline nanostructures were prepared by hydrothermal process. The products were characterized in detail by multiform techniques: X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Experimental results indicate that the temperature plays important roles in determining produce {alpha}-MnO{sub 2} and {beta}-MnO{sub 2} nanorods. In addition, the as-prepared {alpha}-MnO{sub 2} and {beta}-MnO{sub 2} nanorods showed excellent catalytic performance in the Fenton-like reaction.

Cao, Guangsheng, E-mail: daqingcgs@163.com [Key Laboratory of Enhanced Oil and Gas Recovery of Ministry of Education, Daqing Petroleum Institute, Daqing 163318 (China)] [Key Laboratory of Enhanced Oil and Gas Recovery of Ministry of Education, Daqing Petroleum Institute, Daqing 163318 (China); Su, Ling; Zhang, Xiaojuan; Li, Hui [Key Laboratory of Enhanced Oil and Gas Recovery of Ministry of Education, Daqing Petroleum Institute, Daqing 163318 (China)] [Key Laboratory of Enhanced Oil and Gas Recovery of Ministry of Education, Daqing Petroleum Institute, Daqing 163318 (China)

2010-04-15T23:59:59.000Z

462

Catalytic Hydrothermal Gasification of Lignin-Rich Biorefinery Residues and Algae Final Report  

SciTech Connect (OSTI)

This report describes the results of the work performed by PNNL using feedstock materials provided by the National Renewable Energy Laboratory, KL Energy and Lignol lignocellulosic ethanol pilot plants. Test results with algae feedstocks provided by Genifuel, which provided in-kind cost share to the project, are also included. The work conducted during this project involved developing and demonstrating on the bench-scale process technology at PNNL for catalytic hydrothermal gasification of lignin-rich biorefinery residues and algae. A technoeconomic assessment evaluated the use of the technology for energy recovery in a lignocellulosic ethanol plant.

Elliott, Douglas C.; Neuenschwander, Gary G.; Hart, Todd R.; Rotness, Leslie J.; Zacher, Alan H.; Santosa, Daniel M.; Valkenburt, Corinne; Jones, Susanne B.; Tjokro Rahardjo, Sandra A.

2009-11-03T23:59:59.000Z

463

Kinetic control of catalytic CVD for high quality graphene at low temperatures  

E-Print Network [OSTI]

Kinetic control of catalytic CVD for high quality graphene at low temperatures Robert S. Weatherup1, Bruno Dlubak1, Stephan Hofmann1,* 1Dept. of Engineering, University of Cambridge, Cambridge CB3 0FA, UK ABSTRACT Low temperature (~600°C... ), scalable chemical vapor deposition of high quality, uniform mono-layer graphene is demonstrated with a mapped Raman 2D/G ratio of >3.2, D/G ratio ? 0.08 and carrier mobilities of ? 3000cm2V-1s-1 on SiO2 support. A kinetic growth model for graphene CVD...

Weatherup, Robert S.; Dlubak, Bruno; Hofmann, Stephan

2012-10-01T23:59:59.000Z

464

In-Situ Catalytic Fast Pyrolysis Technology Pathway | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Year in3.pdfEnergy Health andofIan Kalin About Us Ian KalinEditionIn-Situ Catalytic Fast

465

Effect of surface structure on catalytic reactions: A sum frequency generation surface vibrational spectroscopy study  

SciTech Connect (OSTI)

In the results discussed above, it is clear that Sum Frequency Generation (SFG) is a unique tool that allows the detection of vibrational spectra of adsorbed molecules present on single crystal surfaces under catalytic reaction conditions. Not only is it possible to detect active surface intermediates, it is also possible to detect spectator species which are not responsible for the measured turnover rates. By correlating high-pressure SFG spectra under reaction conditions and gas chromatography (GC) kinetic data, it is possible to determine which species are important under reaction intermediates. Because of the flexibility of this technique for studying surface intermediates, it is possible to determine how the structures of single crystal surfaces affect the observed rates of catalytic reactions. As an example of a structure insensitive reaction, ethylene hydrogenation was explored on both Pt(111) and Pt(100). The rates were determined to be essentially the same. It was observed that both ethylidyne and di-{sigma} bonded ethylene were present on the surface under reaction conditions on both crystals, although in different concentrations. This result shows that these two species are not responsible for the measured turnover rate, as it would be expected that one of the two crystals would be more active than the other, since the concentration of the surface intermediate would be different on the two crystals. The most likely active intermediates are weakly adsorbed molecules such as {pi}-bonded ethylene and ethyl. These species are not easily detected because their concentration lies at the detection limit of SFG. The SFG spectra and GC data essentially show that ethylene hydrogenation is structure insensitive for Pt(111) and Pt(100). SFG has proven to be a unique and excellent technique for studying adsorbed species on single crystal surfaces under high-pressure catalytic reactions. Coupled with kinetic data obtained from gas chromatography measurements, it can give much insight into how the structure of a single crystal surface affects the chemistry of a catalytic reaction by detecting surface species under reaction conditions.

McCrea, Keith R.

2001-09-07T23:59:59.000Z

466

Evidence for an RNA-based catalytic mechanism in eukaryotic nuclear ribonuclease P.  

E-Print Network [OSTI]

neighbor is itali- cized+) Inspection of Figure 4 shows that these oligo- nucleotides could result only from cleavage at the normal RNase P site, –ApUp21Afp11GpC– for pre-G1Phe and –ApUp 21Afp11ApC– for pre-A1Phe+ In contrast, RNase P treatment...Evidence for an RNA-based catalytic mechanism in eukaryotic nuclear ribonuclease P BRIAN C. THOMAS,1,2,5 JOEL CHAMBERLAIN,3,6 DAVID R. ENGELKE,3,4 and PETER GEGENHEIMER1,2 1Department of Molecular Biosciences, The University of Kansas, 2045 Haworth...

Thoms, Brian C; Chamberlain, Joel; Engelke, David R; Gegenheimer, Peter Albert

2000-01-01T23:59:59.000Z

467

Does H2O improve the catalytic activity of Au1-4/MgO towards CO oxidation?  

E-Print Network [OSTI]

The present density functional theory study addresses the question whether the presence of H2O influences the catalytic activity of small gold clusters, Au1-4/MgO(100), towards the oxidation of carbon monoxide. To this end, we studied the (co-)adsorption of H2O and CO/O2 on these gold clusters. The ground state structures in the presence of all three molecular species, that we found, are Au1O2/MgO and Au2-4CO/MgO with H2O adsorbed on the surface in the proximity of the clusters-molecule complex. In this configuration the catalytic activity of Au1-4/MgO is indifferent to the presence of H2O. We also found that a stable, highly activated hydroperoxyl-hydroxyl complex, O2H\\dot\\dot OH, can be formed on Au1,3/MgO. For the catalytic active system Au8/MgO, it has been predicted that this complex opens an alternative catalytic reaction pathway towards CO oxidation. Our results suggest that this water mediated catalytic cycle is unlikely to occur on Au1,3/MgO. In the case of Au1/MgO the cycle is interrupted by the dis...

Amft, Martin

2011-01-01T23:59:59.000Z

468

Catalytic Distillation  

E-Print Network [OSTI]

removing both will occur in the temperature range ne~ded high and low boilers to maintain the tower for reaction. One limitation may be .I the composition profile, exothermic reactions critical point of the system, above w~ich can be easily temperature... with significantly less energy. There are two primary reasons for energy reduction: 1. The heat of reaction for exothermic reactions is fully re covered as useful boilup for fractionation. 2. Fewer attendant distillations are normally required than for a...

Smith, L. A., Jr.; Hearn, D.; Wynegar, D. P.

1984-01-01T23:59:59.000Z

469

Final Technical Report "Catalytic Hydrogenation of Carbon Monoxide and Olefin Oxidation" Grant number : DE-FG02-86ER13615  

SciTech Connect (OSTI)

Title: Catalytic Hydrogenation of Carbon Monoxide and Olefin Oxidation Grant No. DE-FG02-86ER13615 PI: Wayland, B. B. (wayland@sas.upenn.edu) Abstract Development of new mechanistic strategies and catalyst materials for activation of CO, H2, CH4, C2H4, O2, and related substrates relevant to the conversion of carbon monoxide, alkanes, and alkenes to organic oxygenates are central objectives encompassed by this program. Design and synthesis of metal complexes that manifest reactivity patterns associated with potential pathways for the hydrogenation of carbon monoxide through metallo-formyl (M-CHO), dimetal ketone (M-C(O)-M), and dimetal dionyl (M-C(O)-C(O)-M) species is one major focus. Hydrocarbon oxidation using molecular oxygen is a central goal for methane activation and functionalization as well as regioselective oxidation of olefins. Discovery of new reactivity patterns and control of selectivity are pursued through designing new metal complexes and adjusting reaction conditions. Variation of reaction media promotes distinct reaction pathways that control both reaction rates and selectivities. Dimetalloradical diporphyrin complexes preorganize transition states for substrate reactions that involve two metal centers and manifest large rate increases over mono-metalloradical reactions of hydrogen, methane, and other small molecule substrates. Another broad goal and recurring theme of this program is to contribute to the thermodynamic database for a wide scope of organo-metal transformations in a range of reaction media. One of the most complete descriptions of equilibrium thermodynamics for organometallic reactions in water and methanol is emerging from the study of rhodium porphyrin substrate reactions in aqueous and alcoholic media. Water soluble group nine metalloporphyrins manifest remarkably versatile substrate reactivity in aqueous and alcoholic media which includes producing rhodium formyl (Rh-CHO) and hydroxy methyl (Rh-CH2OH) species. Exploratory directions for this program include expending new strategies for anti-Markovnikov addition of water, alcohols, and amines with olefins, developing catalytic reactions of CO to give formamides and formic esters, and evaluating the potential for coupling reactions of CO to produce organic building blocks.

Wayland, B.B.

2009-08-31T23:59:59.000Z

470

Localization of a gene for X-linked nonspecific mental retardation (MRX24) in Xp22.2-p22.3  

SciTech Connect (OSTI)

Nonspecific X-linked mental retardation (MRX) includes several distinct genetic entities in which mental retardation is not associated with additional distinguishing physical changes. We report linkage data in a Spanish family with MRX, using polymorphic DNA markers distributed over the X chromosome. Two-point linkage analysis demonstrated close linkage between the MRX locus and DXS85 in Xp22.3 with a peak lod score of 2.28 at a {theta} = 0.00. Analysis of multiple informative meioses suggested a localization of the MRX locus (MRX24) between DXS278 and DXS207. Multipoint linkage analysis resulted in a maximum LOD score of 2.45 at 3cM proximal to DXS85, and allowed us to reject a localization of the MRX24 gene in all other regions from Xp21-Xqter. These findings localize the MRX24 gene in the chromosomal region Xp22.2-p22.3. 11 refs., 2 figs., 2 tabs.

Martinez, F.; Palau, F.; Prieto, F. [Hospital Universitario La Fe, Valencia (Spain)] [and others

1995-01-30T23:59:59.000Z

471

Remarkable catalytic activity of cobalt tetraphenylporphyrin modified on a titania for the oxidation of carbon monoxide below room temperature  

SciTech Connect (OSTI)

CoTPP on TiO/sub 2/-120s modified at 250 /sup 0/C under vacuum catalytically oxidized carbon monoxide rapidly with oxygen even at -79/sup 0/C. Its catalytic activity was incomparably higher than that of commercial Hopcalite. Comparison of its catalytic performance with those of the same catalyst or different TiO/sub 2/ supporting catalyst both evacuated at 200 /sup 0/C revealed unique features of the present catalyst in terms of its oxygen adsorption, the poisoning of adsorbed oxygen, and the insolubility of the complex in benzene. Both significant structural modification of the complex and its strong interaction with properly dehydrated TiO/sub 2/-120s brought about by evacuation at 250 /sup 0/C may induce such extraordinary activity. 14 references, 4 figures, 5 tables.

Mochida, I.; Iw