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Note: This page contains sample records for the topic "metal catalysts platinum" 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.


1

Exhaust system having a gold-platinum group metal catalyst  

DOE Patents (OSTI)

A method of providing an exhaust treatment device is disclosed. The method includes applying a catalyst including gold and a platinum group metal to a particulate filter. The concentration of the gold and the platinum group metal is sufficient to enable oxidation of carbon monoxide and nitric oxide.

Ragle, Christie Susan (Havana, IL); Silver, Ronald G. (Peoria, IL); Zemskova, Svetlana Mikhailovna (Edelstein, IL); Eckstein, Colleen J. (Metamora, IL)

2011-12-06T23:59:59.000Z

2

Noble Metal Catalysts for Mercury Oxidation in Utility Flue Gas: Gold, Palladium and Platinum Formulations  

Science Conference Proceedings (OSTI)

The use of noble metals as catalysts for mercury oxidation in flue gas remains an area of active study. To date, field studies have focused on gold and palladium catalysts installed at pilot scale. In this article, we introduce bench-scale experimental results for gold, palladium and platinum catalysts tested in realistic simulated flue gas. Our initial results reveal some intriguing characteristics of catalytic mercury oxidation and provide insight for future research into this potentially important process.

Presto, A.A.; Granite, E.J

2008-07-01T23:59:59.000Z

3

Ethanol oxidation on metal oxide-supported platinum catalysts  

SciTech Connect

Ethanol is a renewable fuel that can be used as an additive to gasoline (or its substitute) with the advantage of octane enhancement and reduced carbon monoxide exhaust emissions. However, on Ethanol is a renewable fuel that can be used as an additive to gasoline (or its substitute) with the advantage of octane enhancement and reduced carbon monoxide exhaust emissions. However, on the standard three-way catalysts, the conversion of unburned ethanol is low because both ethanol and some of its partially oxidized derivatives are highly resistant to oxidation. A combination of first-principles density-functional theory (DFT) based calculations and in-situ diffuse reflectance infrared spectroscopy (DRIFTS) analysis was applied to uncover some of the fundamental phenomena associated with ethanol oxidation on Pt containing catalysts. In particular, the objective was to analyze the role of the oxide (i.e., ?-Al2O3 or SiO2) substrate on the ethanol oxidation activity. The results showed that Pt nanoparticles trap and accumulate oxygen at their surface and perimeter sites and play the role of “stoves” that burn ethanol molecules and their partially oxidized derivatives to the “final” products. The ?-Al2O3 surfaces provided higher mobility of the fragments of ethanol molecules than the SiO2 surface and hence increased the supply rate of these objects to the Pt particles. This will in turn produce a higher conversion rate of unburned ethanol.and some of its partially oxidized derivatives are highly resistant to oxidation. A combination of first-principles density-functional theory (DFT) based calculations and in-situ diffuse reflectance infrared spectroscopy (DRIFTS) analysis was applied to uncover some of the fundamental phenomena associated with ethanol oxidation on Pt containing catalysts. In particular, the objective was to analyze the role of the oxide (i.e., ?-Al2O3 or SiO2) substrate on the ethanol oxidation activity. The results showed that Pt nanoparticles trap and accumulate oxygen at their surface and perimeter sites and play the role of “stoves” that burn ethanol molecules and their partially oxidized derivatives to the “final” products. The ?-Al2O3 surfaces provided higher mobility of the fragments of ethanol molecules than the SiO2 surface and hence increased the supply rate of these objects to the Pt particles. This will in turn produce a higher conversion rate of unburned ethanol.

L. M. Petkovic 090468; Sergey N. Rashkeev; D. M. Ginosar

2009-09-01T23:59:59.000Z

4

Dispersion enhanced metal/zeolite catalysts  

DOE Patents (OSTI)

Dispersion stabilized zeolite supported metal catalysts are provided as bimetallic catalyst combinations. The catalyst metal is in a reduced zero valent form while the dispersion stabilizer metal is in an unreduced ionic form. Representative catalysts are prepared from platinum or nickel as the catalyst metal and iron or chromium dispersion stabilizer.

Sachtler, Wolfgang M. H. (Evanston, IL); Tzou, Ming-Shin (Evanston, IL); Jiang, Hui-Jong (Evanston, IL)

1987-01-01T23:59:59.000Z

5

Platinum-ruthenium-palladium alloys for use as a fuel cell catalyst  

DOE Patents (OSTI)

A noble metal alloy composition for a fuel cell catalyst, a ternary alloy composition containing platinum, ruthenium and palladium. The alloy shows increased activity as compared to well-known catalysts.

Gorer, Alexander (Sunnyvale, CA)

2002-01-01T23:59:59.000Z

6

Novel platinum/carbon catalysts with cluster size control for...  

NLE Websites -- All DOE Office Websites (Extended Search)

Project overview - Cluster chemistry - Catalysts and supports * Experimental - Novel catalyst preparation * Results - Metal cluster size - Electrochemical properties * Summary...

7

Reactivity and stability of platinum and platinum alloy catalysts toward the oxygen reduction reaction  

E-Print Network (OSTI)

Density functional theory (DFT) is used to study the reactivity of Pt and Pt-M (M: Pd, Co, Ni, V, and Rh) alloy catalysts towards the oxygen reduction reaction (ORR) as a function of the alloy overall composition and surface atomic distribution and compared to that on pure Pt surfaces. Reactivity is evaluated on the basis of the adsorption strength of oxygenated compounds which are intermediate species of the four-electron oxygen reduction reaction, separating the effect of the first electron-proton transfer from that of the three last electron-proton transfer steps. It is found that most homogeneous distribution PtxM catalysts thermodynamically favor the dissociation of adsorbed OOH in comparison with pure Platinum and adsorb strongly O and OH due to the strong oxyphilicity of the M elements. On the other hand, in all cases skin Platinum surfaces catalysts do not favor the dissociation of adsorbed OOH and do favor the reduction of M-O and M-OH with respect to Platinum. Considering the overall pathway of the reactions to catalyze the ORR most of the skin Platinum monolayer catalysts provide more negative free energy changes and should behave at least in a similar way than Platinum in following order: Pt3V (skin Pt) > Pt3Co (skin Pt) > Pt3Ni (skin Pt) > Pt > PtPd (skin) > Pt4Rh (skin Pt) > PtPd3 (skin ). In all cases, the reactivity is shown to be not only sensitive to the overall composition of the catalyst, but most importantly to the surface atomic distribution. Proposed electrochemical dissolution reactions of the catalyst atoms are also analyzed for the ORR catalysts, by computing the free energy changes of Platinum and bimetallic Pt-X (X: Co, Pd, Ni, and Rh) catalysts. It is found that Platinum is thermodynamically more stable than Pt-alloys in Pt3Co, Pt3Pd, Pt3Ni and Pt4Rh.

Calvo, Sergio Rafael

2007-12-01T23:59:59.000Z

8

Monodisperse Platinum and Rhodium Nanoparticles as Model Heterogeneous Catalysts  

E-Print Network (OSTI)

R. Structure of Metallic Catalysts ; Academic Press: London,pretreatments of the Rh catalysts and analyzing thea Pt(octahedra)/SBA-15 catalyst increased from 0.01 to 28

Coble, Inger M

2008-01-01T23:59:59.000Z

9

Reaction selectivity studies on nanolithographically-fabricated platinum model catalyst arrays  

E-Print Network (OSTI)

Structure of Metallic Catalysts. Academic Press, London,R. Structure of Metallic Catalysts. Academic Press, London,Ethylene on Metallic Catalysts, National Standard Reference

Grunes, Jeffrey Benjamin

2004-01-01T23:59:59.000Z

10

Reforming with an improved platinum-containing catalyst  

Science Conference Proceedings (OSTI)

There is disclosed a catalyst, which catalyst comprises a physical particle-form mixture of a component A and a component B , said component A comprising one or more group VIII noble metals and a combined halogen deposed on a refractory inorganic oxide and said component B comprising a metal from group IVB or group VB of the periodic table of elements and a combined halogen deposed on a refractory inorganic oxide. Such catalyst is suitable for use in a hydrocarbon conversion reaction zone. The catalyst can be employed in a process for the reforming of a hydrocarbon stream, which process comprises contacting said stream in a reaction zone under reforming conditions and in the presence of hydrogen with said catalyst. The catalyst is not presulfided. A preferred process comprises contacting a hydrocarbon stream that contains a substantial amount of sulfur.

Bertolacini, R.J.; Lysholm, D.L.; Pellet, R.J.

1982-10-12T23:59:59.000Z

11

of hydrogen-powered cars," he says. But a major hurdle remains: the cost of platinum metal  

E-Print Network (OSTI)

of hydrogen-powered cars," he says. But a major hurdle remains: the cost of platinum metal needed to produce nothing but pure water as exhaust and clean electricity for power. At the heart of every fuel cell is an advanced plastic membrane coated with a platinum catalyst. That's where the production of electricity takes

12

NREL Team Creates High-Activity, Durable Platinum Extended Surface Catalyst for Fuel Cells (Fact Sheet)  

DOE Green Energy (OSTI)

Researchers with NREL's Fuel Cell team showed that platinum can replace copper nanowires in such a way that high-surface-area and high-specific-activity catalysts are produced, potentially allowing for lower-cost catalysts.

Not Available

2011-02-01T23:59:59.000Z

13

Reforming with an improved platinum-containing catalyst  

Science Conference Proceedings (OSTI)

A catalyst is disclosed which comprises a physical particle-form mixture of a Component A and a Component B. Said Component A comprises one or more Group VIII noble metals and combined halogen deposed on a refractory inorganic oxide and said Component B comprising a metal from Group IVB or Group VB of the Periodic Table of Elements and a combined halogen deposed on a refrac inorganic oxide. Such catalyst is suitable for use in a hydrocarbon conversion reaction zone. The catalyst can be employed in a process for the reforming of a hydrocarbon stream, which process comprises contacting said stream in a reaction zone under reforming conditions and in the presence hydrogen with said catalyst. The catalyst is not presulfided. A preferred process comprises contacting a hydrocarbon stream that contains a substantial amount of sulfur.

Pellet, R.J.; Bertolacini, R.J.; Lysholm, D.L.

1983-08-30T23:59:59.000Z

14

Nanolithographic Fabrication and Heterogeneous Reaction Studies of Two-Dimensional Platinum Model Catalyst Systems  

E-Print Network (OSTI)

and truly tune the catalyst to the reaction. References 1.Gavriilidis, A. Varma, Catalyst Design, Cambridge UniversityStructure of Metallic Catalysts, Academic Press, London,

Contreras, A.M.

2006-01-01T23:59:59.000Z

15

Transition metal sulfide loaded catalyst  

DOE Patents (OSTI)

A zeolite-based catalyst is described for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C[sub 2]+ hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

Maroni, V.A.; Iton, L.E.; Pasterczyk, J.W.; Winterer, M.; Krause, T.R.

1994-04-26T23:59:59.000Z

16

Transition metal sulfide loaded catalyst  

DOE Patents (OSTI)

A zeolite based catalyst for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C.sub.2 + hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

Maroni, Victor A. (Naperville, IL); Iton, Lennox E. (Downers Grove, IL); Pasterczyk, James W. (Westmont, IL); Winterer, Markus (Westmont, IL); Krause, Theodore R. (Lisle, IL)

1994-01-01T23:59:59.000Z

17

Textured Metal Catalysts for Heterogeneous Catalysis ...  

Biomass and Biofuels Advanced Materials Textured Metal Catalysts for Heterogeneous Catalysis Pacific Northwest National Laboratory. Contact ...

18

Stabilization of Nickel Metal Catalysts for Aqueous ...  

Biomass and Biofuels Stabilization of Nickel Metal Catalysts for Aqueous Processing Systems Pacific Northwest National Laboratory.

19

Nanosegregated Cathode Catalysts with Ultra-Low Platinum Loading  

NLE Websites -- All DOE Office Websites (Extended Search)

2009 DOE EERE Kick-off Meeting 2009 DOE EERE Kick-off Meeting Announcement No: DE-PS36-08GO98010 Topic: 1A Nanosegregated Cathode Catalysts with Ultra-Low Platinum Loading Argonne National Laboratory Materials Science Division PI: Nenad M. Markovic Co-PI: Vojislav R. Stamenkovic Subcontractors: * Oak Ridge National Laboratory - Karren More * Jet Propulsion Laboratory - NASA - S.R. Narayan * Brown University - Shouheng Sun * Indiana University Purdue - Goufeng Wang * 3M Company - Radoslav Atanasoski Overview Timeline * Project start: 9/2009 * Project end: 9/2012 Barriers ~ 30-40% (!!!) Cathode kinetics * The main losses: CATHODE 1) High content of Pt 2) Poor activity: Pt/C = Pt-poly/10 3) Durability (Pt dissolves: power loss) 4) Carbon support corrosion Budget * Total Project funding $ 6.5M

20

Non-Noble Metal Water Electrolysis Catalysts  

This invention comprises an inexpensive catalyst system for water electrolyzers by replacing the noble-metal catalysts that are typically used in ...

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Bridge to Fuel Cell Molecular Catalysis: 3D Non-Platinum Group Metal  

NLE Websites -- All DOE Office Websites (Extended Search)

Bridge to Fuel Cell Molecular Catalysis: 3D Non-Platinum Group Metal Bridge to Fuel Cell Molecular Catalysis: 3D Non-Platinum Group Metal Catalyst in MEAs Title Bridge to Fuel Cell Molecular Catalysis: 3D Non-Platinum Group Metal Catalyst in MEAs Publication Type Journal Article Year of Publication 2012 Authors Zhu, Xiaobing, John B. Kerr, Qinggang He, Gi Suk Hwang, Zulima Martin, Kyle Clark, Adam Z. Weber, and Nana Zhao Journal ECS Transactions Volume 45 Issue 2 Pagination 143 - 152 Date Published 04/2012 ISSN 1938-6737 Abstract Transition metal porphyrin complexes have been mounted in a three dimensional homogenous distribution inside the ionomer of catalyst layers in MEAs to achieve competitive fuel cell catalysis activity. The effect of electrode components including ionomer, carbon, catalyst, and mediator, and ionomer film thickness, is investigated in fuel cell molecular catalysis system. Membrane electrode assembly (MEA) durability testing has been conducted. SEM and TEM techniques are employed to investigate molecular catalysis electrode micro- and nano- structure and morphology. To date, surprisingly, the best fuel cell performance, i.e. 1280 mA/cm2 of maximum/short-circuit current density is achieved, approaching that of Pt-based electrode, indicating higher turnover frequencies than Pt although with poorer voltages.

22

Effect of germanium and zirconium on the activity of a platinum catalyst in dehydrocyclization of n-hexane  

Science Conference Proceedings (OSTI)

Catalytic reforming is now developing in the direction of higher selectivity for aromatization of paraffinic hydrocarbons. The alumino-platinum catalyst used for this purpose has a number of shortcomings, the most important one being a relatively low selectivity and stability under conditions of rigid temperature conditions. By introducing further components into alumina-platinum catalysts these shortcomings are partly overcome. The effect of germanium and zirconium additives into an alumina-platinum catalyst is examined in this paper.

Nadirov, N.K.; Vozdvizhenskii, V.F.; Kondratkova, N.I.; Fatkulina, A.A.

1985-01-01T23:59:59.000Z

23

Metal phthalocyanine catalysts  

DOE Patents (OSTI)

As a new composition of matter, alkali metal or ammonium or tetraalkylammonium diazidoperfluorophthalocyanatoferrate. Other embodiments of the invention comprise compositions wherein the metal of the coordination complex is cobalt, manganese and chromium.

Ellis, Jr., Paul E. (Downingtown, PA); Lyons, James E. (Wallingford, PA)

1994-01-01T23:59:59.000Z

24

Metal phthalocyanine catalysts  

DOE Patents (OSTI)

A new composition of matter is described which is an alkali metal or ammonium or tetraalkylammonium diazidoperfluorophthalocyanatoferrate. Other embodiments of the invention comprise compositions wherein the metal of the coordination complex is cobalt, manganese and chromium.

Ellis, P.E. Jr.; Lyons, J.E.

1994-10-11T23:59:59.000Z

25

DOE Hydrogen and Fuel Cells Program Record 11013: Platinum Group Metal Loading in PEMFC Stacks  

NLE Websites -- All DOE Office Websites (Extended Search)

3 Date: June 2, 2011 3 Date: June 2, 2011 Title: Platinum Group Metal Loading in PEMFC Stacks Originator: Jacob Spendelow and Dimitrios Papageorgopoulos Approved by: Sunita Satyapal Date: July 25, 2011 Item: Total loading of platinum group metals (PGMs) in state-of-the-art polymer electrolyte membrane fuel cell stacks has decreased by 2 orders of magnitude since the 1960s and 1 order of magnitude since the mid-1980s. Supporting Information: Prior to 1988, state-of-the-art polymer electrolyte membrane fuel cell (PEMFC) electrodes were constructed using Pt-based catalysts pressed directly into the surface of the polymer electrolyte membrane (PEM). Catalyst loadings were 35 mg/cm 2 in the PEMFC electrodes used in the 1960s in NASA's Gemini program [1], though

26

Supported metal alloy catalysts  

DOE Patents (OSTI)

A process of preparing a Group IV, V, or VI metal carbonitride including reacting a Group IV, V, or VI metal amide complex with ammonia to obtain an intermediate product; and, heating the intermediate product to temperatures and for times sufficient to form a Group IV, V, or VI metal carbonitride is provided together with the product of the process and a process of reforming an n-alkane by use of the product.

Barrera, Joseph (Albuquerque, NM); Smith, David C. (Santa Clara, CA)

2000-01-01T23:59:59.000Z

27

Molecular-scale, Three-dimensional Non-Platinum Group Metal Electrodes for Catalysis of Fuel Cell Reactions  

NLE Websites -- All DOE Office Websites (Extended Search)

Molecular-scale, Three-dimensional Non-Platinum Group Molecular-scale, Three-dimensional Non-Platinum Group Metal Electrodes for Catalysis of Fuel Cell Reactions John B. Kerr Lawrence Berkeley National Laboratory (LBNL) September 30, 2009 Team Members: Adam Weber, Rachel Segalman, Robert Kostecki, Jeff Reimer, John Arnold, Martin Head-Gordon (LBNL). Piotr Zelenay, James Boncella, Yu Seung Kim, Neil Henson, Jerzy Chlistunoff (LANL). Steve Hamrock, Radoslav Atanasoski (3M) Budget: DOE share - $9.58MM over four years; 3M share - in-kind over four years. 2 Objectives 1) Demonstrate that non-platinum group metal catalysts can be used for oxygen reduction in polymer-coated electrode structures based on polyelectrolyte membranes. 2) Incorporate catalysts into polymer binders of composite electrodes for the construction of MEAs to demonstrate that this

28

DOE Hydrogen and Fuel Cells Program Record 9018: Platinum Group Metal Loading  

NLE Websites -- All DOE Office Websites (Extended Search)

8 Date: March 23, 2010 8 Date: March 23, 2010 Title: Platinum Group Metal Loading Originator: Jacob Spendelow, Kathi Epping Martin, and Dimitrios Papageorgopoulos Approved by: Sunita Satyapal Date: June 1, 2010 Item: Total content of platinum group metals (PGMs) in state-of-the-art polymer electrolyte membrane fuel cell stacks has decreased by more than 80% since 2005. Improvement in performance and durability at low catalyst loading has allowed fuel cell developers to produce stacks with PGM content lower than the DOE 2010 target. DOE is on track to meet the 2015 PGM total content target on schedule. Supporting Information: DOE regularly determines fuel cell technology status using results reported by fuel cell developers. The results are reviewed in consultation with the FreedomCAR & Fuel

29

Carbon Supported Polyaniline as Anode Catalyst: Pathway to Platinum-Free Fuel Cells  

E-Print Network (OSTI)

The effectiveness of carbon supported polyaniline as anode catalyst in a fuel cell (FC) with direct formic acid electrooxidation is experimentally demonstrated. A prototype FC with such a platinum-free composite anode exhibited a maximum room-temperature specific power of about 5 mW/cm2

Zabrodskii, A G; Malyshkin, V G; Sapurina, I Y

2006-01-01T23:59:59.000Z

30

Formaldehyde yields from methanol electrochemical oxidation on carbon-supported platinum catalysts  

Science Conference Proceedings (OSTI)

The formation of formaldehyde during methanol electrochemical oxidation on supported Pt and Pt-Ru catalysts was investigated. While on solid platinum electrodes, the formaldehyde yields from methanol oxidation are near 30% at low potentials; the yields fall below 2% for methanol electrochemical oxidation on carbon-supported catalysts in Nafion. The lower formaldehyde yields, which result from more complete methanol oxidation, are believed to arise from the ability of partial oxidation products to be transported to an array of active catalyst sites dispersed within the three-dimensional network of the Nafion film.

Childers, C.L.; Huang, H.; Korzeniewski, C. [Texas Tech Univ., Lubbock, TX (United States). Dept. of Chemistry and Biochemistry

1999-02-02T23:59:59.000Z

31

Nano-Structured Nobel Metal Catalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Nobel Metal Catalysts Nobel Metal Catalysts for Hydrocarbon Reforming Opportunity Research is active on the patent pending technology, titled "Nano- Structured Nobel Metal Catalysts Based on Hexametallate Architecture for the Reforming of Hydrocarbon Fuels." This technology is available for licensing and/or further collaborative research from the U.S. Department of Energy's National Energy Technology Laboratory. Overview Methods for generating synthesis gas from hydrocarbon feedstocks routinely involve the use of a catalyst-a material that speeds up the reaction, but itself is not consumed-to make this process economically feasible. Sulfur, higher hydrocarbons, and olefins present a major technical challenge since these components can deactivate conventional

32

Platinum-, rhenium-, indium-containing catalysts for conversion of hydrocarbons  

Science Conference Proceedings (OSTI)

A process is described for the catalytic reforming of naphtha-boiling range charge stock at reforming conditions with a catalytic composite comprising: (a) a refractory inorganic oxide; (b) a first uniform dispersion of a platinum component and a rhenium component; (c) a second dispersion of an indium component thereover; (d) a halogen component; and (e) a sulfur component.

Antos, G.J.; Wang, L.

1986-12-16T23:59:59.000Z

33

Materials Design of Advanced Performance Metal Catalysts  

SciTech Connect

The contribution of materials design to the fabrication of advanced metal catalysts is highlighted, with particular emphasis on the construction of relatively complex contact structures surrounding metal nanoparticles. Novel advanced metal catalysts can be synthesized via encapsulation of metal nanoparticles into oxide shells, immobilization of metal oxide core-shell structures on solid supports, post-modification of supported metal nanoparticles by surface coating, and premodification of supports before loading metal nanoparticles. Examples on how these materials structures lead to enhanced catalytic performance are illustrated, and a few future prospects are presented.

Ma, Zhen [ORNL; Dai, Sheng [ORNL

2008-01-01T23:59:59.000Z

34

Catalyst regeneration process including metal contaminants removal  

DOE Patents (OSTI)

Spent catalysts removed from a catalytic hydrogenation process for hydrocarbon feedstocks, and containing undesired metals contaminants deposits, are regenerated. Following solvent washing to remove process oils, the catalyst is treated either with chemicals which form sulfate or oxysulfate compounds with the metals contaminants, or with acids which remove the metal contaminants, such as 5-50 W % sulfuric acid in aqueous solution and 0-10 W % ammonium ion solutions to substantially remove the metals deposits. The acid treating occurs within the temperature range of 60.degree.-250.degree. F. for 5-120 minutes at substantially atmospheric pressure. Carbon deposits are removed from the treated catalyst by carbon burnoff at 800.degree.-900.degree. F. temperature, using 1-6 V % oxygen in an inert gas mixture, after which the regenerated catalyst can be effectively reused in the catalytic process.

Ganguli, Partha S. (Lawrenceville, NJ)

1984-01-01T23:59:59.000Z

35

Attrition resistant catalysts and sorbents based on heavy metal poisoned FCC catalysts  

DOE Patents (OSTI)

A heavy metal poisoned, spent FCC catalyst is treated by chemically impregnating the poisoned catalyst with a new catalytic metal or metal salt to provide an attrition resistant catalyst or sorbent for a different catalytic or absorption processes, such as catalysts for Fischer-Tropsh Synthesis, and sorbents for removal of sulfur gasses from fuel gases and flue-gases. The heavy metal contaminated FCC catalyst is directly used as a support for preparing catalysts having new catalytic properties and sorbents having new sorbent properties, without removing or "passivating" the heavy metals on the spent FCC catalyst as an intermediate step.

Gangwal, Santosh (Cary, NC); Jothimurugesan, Kandaswamy (Hampton, VA)

1999-01-01T23:59:59.000Z

36

Attrition resistant catalysts and sorbents based on heavy metal poisoned FCC catalysts  

DOE Patents (OSTI)

A heavy metal poisoned, spent FCC catalyst is treated by chemically impregnating the poisoned catalyst with a new catalytic metal or metal salt to provide an attrition resistant catalyst or sorbent for a different catalytic or absorption process, such as catalysts for Fischer-Tropsh Synthesis, and sorbents for removal of sulfur gases from fuel gases and flue-gases. The heavy metal contaminated FCC catalyst is directly used as a support for preparing catalysts having new catalytic properties and sorbents having new sorbent properties, without removing or passivating the heavy metals on the spent FCC catalyst as an intermediate step.

Gangwal, S.; Jothimurugesan, K.

1999-07-27T23:59:59.000Z

37

Development of Ultra-low Platinum Alloy Cathode Catalyst for PEM Fuel Cells  

NLE Websites -- All DOE Office Websites (Extended Search)

Development of Ultra-low Platinum Alloy Development of Ultra-low Platinum Alloy C th d C t l t f PEM F l C ll Cathode Catalyst for PEM Fuel Cells 2010 DOE Hydrogen Program Fuel Cell Project Kick-Off P I : Branko N Popov P. I.: Branko N. Popov Center for Electrochemical Engineering University of South Carolina Columbia SC 29208. September 28, 2010 This presentation does not contain any proprietary, confidential, or otherwise restricted information Center for Electrochemical Engineering, University of South Carolina 1 Overview Timeline * S Start d date: J June 01 2010 01 2010 * End date: Nov 30 2012 (Phase I) : May 31 2014 (Phase II) Budget * Total project funding ¾ DOE share: $ 4 400 000 ¾ DOE share: $ 4,400,000 ¾ Contractor share: $1,100,000 * Incremental funding received in FY10: $750,000

38

Single-layer transition metal sulfide catalysts  

SciTech Connect

Transition Metal Sulfides (TMS), such as molybdenum disulfide (MoS.sub.2), are the petroleum industry's "workhorse" catalysts for upgrading heavy petroleum feedstocks and removing sulfur, nitrogen and other pollutants from fuels. We have developed an improved synthesis technique to produce SLTMS catalysts, such as molybdenum disulfide, with potentially greater activity and specificity than those currently available. Applications for this technology include heavy feed upgrading, in-situ catalysis, bio-fuel conversion and coal liquefaction.

Thoma, Steven G. (Albuquerque, NM)

2011-05-31T23:59:59.000Z

39

Single-layer transition metal sulfide catalysts  

DOE Patents (OSTI)

Transition Metal Sulfides (TMS), such as molybdenum disulfide (MoS.sub.2), are the petroleum industry's "workhorse" catalysts for upgrading heavy petroleum feedstocks and removing sulfur, nitrogen and other pollutants from fuels. We have developed an improved synthesis technique to produce SLTMS catalysts, such as molybdenum disulfide, with potentially greater activity and specificity than those currently available. Applications for this technology include heavy feed upgrading, in-situ catalysis, bio-fuel conversion and coal liquefaction.

Thoma, Steven G. (Albuquerque, NM)

2011-05-31T23:59:59.000Z

40

Hydrothermal alkali metal catalyst recovery process  

DOE Patents (OSTI)

In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered from the particles primarily in the form of water soluble alkali metal formates by treating the particles with a calcium or magnesium-containing compound in the presence of water at a temperature between about 250.degree. F. and about 700.degree. F. and in the presence of added carbon monoxide. During the treating process the water insoluble alkali metal compounds comprising the insoluble alkali metal residues are converted into water soluble alkali metal formates. The resultant aqueous solution containing water soluble alkali metal formates is then separated from the treated particles and any insoluble materials formed during the treatment process, and recycled to the gasification process where the alkali metal formates serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst. This process permits increased recovery of alkali metal constituents, thereby decreasing the overall cost of the gasification process by reducing the amount of makeup alkali metal compounds necessary.

Eakman, James M. (Houston, TX); Clavenna, LeRoy R. (Baytown, TX)

1979-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Final Report - Novel Approach to Non-Precious Metal Catalysts  

Science Conference Proceedings (OSTI)

This project was directed at reducing the dependence of PEM fuel cells catalysts on precious metals. The primary motivation was to reduce the cost of the fuel cell stack as well as the overall system cost without loss of performance or durability. Platinum is currently the catalyst of choice for both the anode & the cathode. However, the oxygen reduction reaction (ORR) which takes place on the cathode is an inherently slower reaction compared to the hydrogen oxidation reaction (HOR) which takes place on the anode. Therefore, more platinum is needed on the cathode than on the anode to achieve suitable fuel cell performance. As a result, developing a replacement for platinum on the cathode side will have a larger impact on overall stack cost. Thus, the specific objectives of the project, as stated in the solicitation, were to produce non-precious metal (NPM) cathode catalysts which reduce dependence on precious metals (especially Pt), perform as well as conventional precious metal catalysts currently in use in MEAs, cost 50% less compared to a target of 0.2 g Pt/peak kW, & demonstrate durability of greater than 2000 hours with less than 10% power degradation. During the term of the project, DOE refined its targets for NPM catalyst activity to encompass volumetric current density. The DOE Multi-Year RD&D Plan (2005) volumetric current density targets for 2010 & 2015 are greater than 130 A/cm3 & 300 A/cm3 at 800 mV (IR-free) respectively. The initial approach to achieve these targets was to use vacuum deposition techniques to deposit transition metal, carbon and nitrogen moieties onto 3M’s nanostructured thin film (NSTF) catalyst support. While this approach yielded compounds with similar physicochemical characteristics as catalysts reported by others as active for ORR, the activity of these vacuum deposited catalysts was not satisfactory. In order to enhance catalytic activity additional process steps were introduced, the most successful of which was a thermal treatment. To withstand the high temperatures (~900 ºC), alternative supports to NSTF were introduced. A variety of carbon fabrics were tested for this purpose. Vacuum deposited materials were used as precursors & physicochemically transformed via thermal treatment to produce substantially better catalytic activity. This activity was further amplified by increasing the surface area of the carbon fabrics which lead to significant gains in fuel cell performance. The second synthetic approach is based on 3M nanotechnology & involves depositing precursor catalytic materials on high surface area supports, initially carbon. These materials were subsequently thermally treated in a nitrogen-containing gas atmosphere. While this approach is similar to others reported in the literature, we exploited 3M’s nanotechnology platform & our expertise in the areas of synthesis & application of the precursor on the substrate. ORR activity proved higher for the materials produced via this approach. In fact, to our knowledge, the performance achieved on this effort exceeded the best previously reported for any NPM catalyst. With 4-nitroaniline as a precursor, the volumetric current density of our material achieved 19 A/cm3 at 800 mV, exceeding the value reported by DOE as the 2005 status (8 A/cm3) by a factor of more than two. We emphasize a unique feature of this project is that all measurements were done in real PEM fuel cells using 50-cm2 MEAs, therefore rendering credibility to the data for practical projection to a fuel cell stack application. In addition, with the price of the precursor nitroaniline only $1.5 kg on the commodity market enabling the DOE requirement of reducing the cost of the catalyst by a factor of two. A drawback of high-performing catalysts on carbon supports is their poor durability. Therefore, in the last stage of this project the focus of shifted toward improving the stability of the NPM catalyst. For that purpose alternative supports to carbon were introduced, The best catalyst synthesis methods remained practically the same for the new supports. Conseque

Atanasoski, Radoslav

2007-11-17T23:59:59.000Z

42

Platinum Group Metal Recycling Technology Development - Final Report  

DOE Green Energy (OSTI)

BASF Catalysts LLC, formerly Engelhard Corporation, has completed a project to recover Pt from PEM fuel cell membrane electrode assemblies. The project, which began in 2003, has met the project objective of an environmentally-friendly, cost-effective method for recovery of platinum without release of hydrogen fluoride. This has been achieved using a combination of milling, dispersion and acid leaching. 99% recovery of Pt was achieved, and this high yield can be scaled up using one vessel for a single leach and rinse. Leaching was been successfully achieved using a 10% solids level, double the original target. At this solids content, the reagent and utility costs represent ~0.35% of the Pt value of a lot, using very conservative assumptions. The main cost of the process is capital depreciation, followed by labor.

Lawrence Shore

2009-08-19T23:59:59.000Z

43

Final Scientific Report : Development of Transition Metal/ Chalcogen Based Cathode Catalysts for PEM Fuel Cells  

DOE Green Energy (OSTI)

The aim of this project was to investigate the potential for using base metal sulfides and selenides as low cost replacements for precious metal catalysts, such as platinum, currently being used in PEM fuel cells. The approach was to deposit thin films of the materials to be evaluated onto inert electrodes and evaluate their activity for the cathode reaction (oxygen reduction) as well as ex-situ structural and compositional characterization. The most active materials identified are CoS2 and the 50:50 solid solution (Co,Ni)S2. However, the OCP of these materials is still considered too low, at 0.83V and 0.89V vs. RHE respectively, for testing in fuel cells. The methods employed here were necessary to compare with the activity of platinum as, when nano-dispersed on carbon supports, the active surface area of these materials is difficult to measure, making comparisons inaccurate. This research adds to the knowledge of potential candidates for platinum replacement in order to reduce the cost of PEM fuel cell technology and promote commercialization. Although the fabrication methods employed here are strictly experimental, methods were also developed to produce nano-dispersed catalysts with similar compositions, structure and activity. Cycling of these catalysts to highly oxidizing potentials resulted in an increase of the open circuit voltage to approach that of platinum, however, it proved difficult to determine why using these dispersed materials. The potential for non-precious, non-metallic, low cost, compound catalysts for PEM fuel cells has been investigated and demonstrated.

Campbell, Stephen, A.

2008-02-29T23:59:59.000Z

44

Stabilization of Nickel Metal Catalysts for Aqueous Processing ...  

Search PNNL. PNNL Home; About; Research; Publications; Jobs; News; Contacts; Stabilization of Nickel Metal Catalysts for Aqueous Processing Systems. ...

45

Platinum  

Science Conference Proceedings (OSTI)

Table 13   Corrosion of platinum in acids...2 Benzoic, all concentrations 130 265 Benzene sulfonic, pure Room <0.05 2 Boric, saturated Boiling <0.05 2 Butyric, all concentrations Boiling <0.05 2 Carbonic, pure 1400 2550 <0.05 2 Chloric, all concentrations Room <0.05 2 Chlorosulfonic, all concentrations Boiling <0.05 2...

46

Formation of {open_quotes}metal wool{close_quotes} structures and dynamics of catalytic etching of platinum surfaces during ammonia oxidation  

SciTech Connect

Reconstruction of a clean surface of a platinum catalyst and a platinum surface covered with gold during ammonia oxidation was studied by SEM observations. It was found that the process of catalytic etching had two sequential stages in which different crystal structures with different rates of growth formed on the surface. The first stage was the formation of parallel facets, and the second stage was the formation of individual microcrystals with perfect crystal faces. It was also found that the second state had a threshold character, beginning after some delay from the start of the reaction. A structure resembling metal wool and consisting of interlaced platinum filaments was found to form on the surface of gold-covered platinum catalysts. Characteristic features of this structure`s development are reported. The growth of filaments is attributed to the vapor-liquid-solid mechanism of whisker growth. On the basis of the observed platinum whisker formation and behavior during ammonia oxidation, a mechanism of catalyst surface reconstruction that explains observed characteristic features of the process of catalytic etching is proposed. 25 refs., 8 figs.

Lyubovsky, M.R.; Barelko, V.V. [Institute of Chemical Physics in Chernogolovka, Moscow (Russian Federation)] [Institute of Chemical Physics in Chernogolovka, Moscow (Russian Federation)

1994-09-01T23:59:59.000Z

47

DOE Hydrogen Analysis Repository: Novel Non-Precious Metal Catalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Novel Non-Precious Metal Catalysts Novel Non-Precious Metal Catalysts Project Summary Full Title: Novel Non-Precious Metal Catalysts for PEMFC: Catalyst Selection through Molecular Modeling and Durability Studies Project ID: 147 Principal Investigator: Branko Popov Brief Description: The University of South Carolina is synthesizing novel non-precious metal electrocatalysts with similar activity and stability as Pt for oxygen reduction reaction (ORR). Keywords: Catalyst; oxygen reduction; non precious metals; molecular modeling; durability Purpose Develop highly active and stable carbon-based metal-free catalysts and carbon composite catalysts with strong Lewis basicity to facilitate the ORR. Performer Principal Investigator: Branko Popov Organization: University of South Carolina Address: 2C19 Swearingen, Chemical Engineering, 301 Main Street

48

Subnanometer platinum clusters highly active and selective catalysts for the oxidative dehydrogenation of propane.  

Science Conference Proceedings (OSTI)

Small clusters are known to possess reactivity not observed in their bulk analogues, which can make them attractive for catalysis. Their distinct catalytic properties are often hypothesized to result from the large fraction of under-coordinated surface atoms. Here, we show that size-preselected Pt{sub 8-10} clusters stabilized on high-surface-area supports are 40-100 times more active for the oxidative dehydrogenation of propane than previously studied platinum and vanadia catalysts, while at the same time maintaining high selectivity towards formation of propylene over by-products. Quantum chemical calculations indicate that under-coordination of the Pt atoms in the clusters is responsible for the surprisingly high reactivity compared with extended surfaces. We anticipate that these results will form the basis for development of a new class of catalysts by providing a route to bond-specific chemistry, ranging from energy-efficient and environmentally friendly synthesis strategies to the replacement of petrochemical feedstocks by abundant small alkanes.

Vajda, S; Pellin, M. J.; Greeley, J. P.; Marshall, C. L.; Curtiss, L. A.; Ballentine, G. A.; Elam, J. W.; Catillon-Mucherie, S.; Redfern, P. C.; Mehmood, F.; Zapol, P.; Yale Univ.

2009-03-01T23:59:59.000Z

49

Synthesis of Metal-Metal Oxide Catalysts and Electrocatalysts  

Platinum is the most efficient electrocatalyst for accelerating the oxygen reduction reaction in fuel cells. Under operating conditions, though, ...

50

Platinum Nanoclusters Out-Perform Single Crystals  

NLE Websites -- All DOE Office Websites (Extended Search)

Platinum Nanoclusters Out-Perform Single Crystals Print Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which many industrial technologies operate-platinum surfaces can change their structure dramatically in response to the presence of high-coverage reactants. High-pressure scanning tunneling microscopes (STM) and ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) at ALS Beamlines 9.3.2 and 11.0.2 allowed researchers to study catalysts' structure and composition under realistic conditions.

51

Platinum Nanoclusters Out-Perform Single Crystals  

NLE Websites -- All DOE Office Websites (Extended Search)

Platinum Nanoclusters Out-Perform Single Crystals Print Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which many industrial technologies operate-platinum surfaces can change their structure dramatically in response to the presence of high-coverage reactants. High-pressure scanning tunneling microscopes (STM) and ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) at ALS Beamlines 9.3.2 and 11.0.2 allowed researchers to study catalysts' structure and composition under realistic conditions.

52

Platinum Nanoclusters Out-Perform Single Crystals  

NLE Websites -- All DOE Office Websites (Extended Search)

Platinum Nanoclusters Out-Perform Single Crystals Print Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which many industrial technologies operate-platinum surfaces can change their structure dramatically in response to the presence of high-coverage reactants. High-pressure scanning tunneling microscopes (STM) and ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) at ALS Beamlines 9.3.2 and 11.0.2 allowed researchers to study catalysts' structure and composition under realistic conditions.

53

Platinum Nanoclusters Out-Perform Single Crystals  

NLE Websites -- All DOE Office Websites (Extended Search)

Platinum Nanoclusters Out-Perform Single Crystals Print Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which many industrial technologies operate-platinum surfaces can change their structure dramatically in response to the presence of high-coverage reactants. High-pressure scanning tunneling microscopes (STM) and ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) at ALS Beamlines 9.3.2 and 11.0.2 allowed researchers to study catalysts' structure and composition under realistic conditions.

54

Platinum Nanoclusters Out-Perform Single Crystals  

NLE Websites -- All DOE Office Websites (Extended Search)

Platinum Nanoclusters Out-Perform Single Crystals Print Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which many industrial technologies operate-platinum surfaces can change their structure dramatically in response to the presence of high-coverage reactants. High-pressure scanning tunneling microscopes (STM) and ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) at ALS Beamlines 9.3.2 and 11.0.2 allowed researchers to study catalysts' structure and composition under realistic conditions.

55

Platinum Nanoclusters Out-Perform Single Crystals  

NLE Websites -- All DOE Office Websites (Extended Search)

Platinum Nanoclusters Out-Perform Single Crystals Print Platinum Nanoclusters Out-Perform Single Crystals Print When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which many industrial technologies operate-platinum surfaces can change their structure dramatically in response to the presence of high-coverage reactants. High-pressure scanning tunneling microscopes (STM) and ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) at ALS Beamlines 9.3.2 and 11.0.2 allowed researchers to study catalysts' structure and composition under realistic conditions.

56

Modeling Low-Platinum-Loading Effects in Fuel-Cell Catalyst Layers  

E-Print Network (OSTI)

Loading Effects in Fuel-Cell Catalyst Layers Wonseok Yoon*CA 94720, USA The cathode catalyst layer within a proton-with low Pt-loading catalyst layers. Model results

Yoon, Wonseok

2013-01-01T23:59:59.000Z

57

Cobalt discovery replaces precious metals as industrial catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Cobalt Discovery Replaces Precious Metals Cobalt Discovery Replaces Precious Metals Cobalt discovery replaces precious metals as industrial catalyst Cobalt holds promise as an industrial catalyst with potential applications in such energy-related technologies such as production of biofuels and reduction of carbon dioxide. November 26, 2012 The artwork depicts the substitution of cobalt for precious metals in catalysis as a variation on the ancient alchemical theme of transmuting base metals into precious ones. The artwork depicts the substitution of cobalt for precious metals in catalysis as a variation on the ancient alchemical theme of transmuting base metals into precious ones. Contact Nancy Ambrosiano Communications Office (505) 699-1149 Email Catalysts are also integral to thousands of industrial, synthetic, and

58

Cobalt discovery replaces precious metals as industrial catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Cobalt Discovery Replaces Precious Metals Cobalt Discovery Replaces Precious Metals Cobalt discovery replaces precious metals as industrial catalyst Cobalt holds promise as an industrial catalyst with potential applications in such energy-related technologies such as production of biofuels and reduction of carbon dioxide. November 26, 2012 The artwork depicts the substitution of cobalt for precious metals in catalysis as a variation on the ancient alchemical theme of transmuting base metals into precious ones. The artwork depicts the substitution of cobalt for precious metals in catalysis as a variation on the ancient alchemical theme of transmuting base metals into precious ones. Contact Nancy Ambrosiano Communications Office (505) 699-1149 Email Catalysts are also integral to thousands of industrial, synthetic, and

59

Cobalt discovery replaces precious metals as industrial catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Cobalt discovery replaces precious metals Cobalt discovery replaces precious metals Cobalt discovery replaces precious metals as industrial catalyst Cobalt holds promise as an industrial catalyst with potential applications in such energy-related technologies such as production of biofuels and reduction of carbon dioxide. November 26, 2012 The artwork depicts the substitution of cobalt for precious metals in catalysis as a variation on the ancient alchemical theme of transmuting base metals into precious ones. The artwork depicts the substitution of cobalt for precious metals in catalysis as a variation on the ancient alchemical theme of transmuting base metals into precious ones. Contact Nancy Ambrosiano Communications Office (505) 699-1149 Email Catalysts are also integral to thousands of industrial, synthetic, and

60

Neutral bimetallic transition metal phenoxyiminato catalysts and related polymerization methods  

SciTech Connect

A catalyst composition comprising a neutral bimetallic diphenoxydiiminate complex of group 10 metals or Ni, Pd or Pt is disclosed. The compositions can be used for the preparation of homo- and co-polymers of olefinic monomer compounds.

Marks, Tobin J. (Evanston, IL); Rodriguez, Brandon A. (Evanston, IL); Delferro, Massimiliano (Chicago, IL)

2012-08-07T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Transition metal-free olefin polymerization catalyst  

DOE Patents (OSTI)

Ethylene and/or propylene are polymerized to form high molecular weight, linear polymers by contacting ethylene and/or propylene monomer, in the presence of an inert reaction medium, with a catalyst system which consists essentially of (1) an aluminum alkyl component, such as trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-octylaluminum and diethylaluminum hydride and (2) a Lewis acid or Lewis acid derivative component, such as B (C.sub.6 F.sub.5).sub.3, [(CH.sub.3).sub.2 N (H) (C.sub.6 H.sub.5)].sup.+ [B (C.sub.6 F.sub.5)4].sup.-, [(C.sub.2 H.sub.5).sub.3 NH].sup.+ [B C.sub.6 F.sub.5).sub.4 ],.sup.-, [C(C.sub.6 F.sub.5).sub.3 ].sup.+ [B(C.sub.6 F.sub.5).sub.4 ].sup.-, (C.sub.2 H.sub.5).sub.2 Al(OCH.sub.3), (C.sub.2 H.sub.5).sub.2 Al(2,6-di-t-butyl-4-methylphenoxide), (C.sub.2 H.sub.5)Al(2,6 -di-t-butylphenoxide).sub.2, (C.sub.2 H.sub.5).sub.2 Al(2,6-di-t-butylphonoxide) , 2,6 -di-t-butylphenol.multidot.methylaluminoxane or an alkylaluminoxane, and which may be completely free any transition metal component(s).

Sen, Ayusman (State College, PA); Wojcinski, II, Louis M. (State College, PA); Liu, Shengsheng (State College, PA)

2001-01-01T23:59:59.000Z

62

Desulfurization with transition metal catalysts. Quarterly summary  

SciTech Connect

The overall objective of this research is to develop desulfurizing transition metal catalysts, which are active in homogeneous media at moderate temperatures and pressures for the purification of coal-derived fuels and chemicals. To this end, the mechanism of action is being examined whereby newly identified nickel(0) complexes desulfurize organosulfur compounds in solution at 65 to 70/sup 0/C. The sulfur compounds under investigation are typical of those commonly encountered in coal-derived liquids and solids, such as thiophenes, sulfides and mercaptans. The following studies on the homogeneous, stoichiometric desulfurizing agent, bis(1,5-cyclooctadiene) nickel(0) ((COD)/sub 2/Ni), were continued: (a) activation of the agent by means of added mono-, bi-/sup 2/ and tri-dentate amines, either of the tertiary or primary amine type; (b) labeling studies designed to reveal the source of the hydrogen that replaces the sulfur in the desulfurization of dibenzothiophene; (c) comparison of the desulfurizing activity of (COD)/sub 2/Ni, both in the presence and in the absence of lithium aluminum hydride; and (d) testing for the role of any biphenylene intermediate in these desulfurizations. Results are reported.

Eisch, J J

1980-04-10T23:59:59.000Z

63

Design Principles for Oxygen-Reduction Activity on Perovskite Oxide Catalysts for Fuel Cells and Metal-air Batteries  

DOE Green Energy (OSTI)

The prohibitive cost and scarcity of the noble-metal catalysts needed for catalysing the oxygen reduction reaction (ORR) in fuel cells and metal-air batteries limit the commercialization of these clean-energy technologies. Identifying a catalyst design principle that links material properties to the catalytic activity can accelerate the search for highly active and abundant transition-metal-oxide catalysts to replace platinum. Here, we demonstrate that the ORR activity for oxide catalysts primarily correlates to {sigma}*-orbital (e{sub g}) occupation and the extent of B-site transition-metal-oxygen covalency, which serves as a secondary activity descriptor. Our findings reflect the critical influences of the {sigma}* orbital and metal-oxygen covalency on the competition between O{sub 2}{sup 2-}/OH{sup -} displacement and OH{sup -} regeneration on surface transition-metal ions as the rate-limiting steps of the ORR, and thus highlight the importance of electronic structure in controlling oxide catalytic activity.

J Suntivich; H Gasteiger; N Yabuuchi; H Nakanishi; J Goodenough; Y Shao-Horn

2011-12-31T23:59:59.000Z

64

Partial oxidation of propane on ceria-and alumina-supported platinum catalysts.  

E-Print Network (OSTI)

??Three Pt/CeO2 catalysts and Pt/Al2O3 catalyst were studied for partial oxidation of propane. The 1 % Pt/CeO2 (C) catalyst which was prepared using CeO2 prepared… (more)

Bansode, Vijaya Anil.

2006-01-01T23:59:59.000Z

65

Electrocatalyst for Oxygen Reduction with Reduced Platinum ...  

Platinum is the most efficient electrocatalyst for accelerating the oxygen reduction reaction in fuel cells. Under operating conditions, though, platinum catalysts ...

66

Hydrous metal oxide catalysts for oxidation of hydrocarbons  

DOE Green Energy (OSTI)

This report describes work performed at Sandia under a CRADA with Shell Development of Houston, Texas aimed at developing hydrous metal oxide (HMO) catalysts for oxidation of hydrocarbons. Autoxidation as well as selective oxidation of 1-octene was studied in the presence of HMO catalysts based on known oxidation catalysts. The desired reactions were the conversion of olefin to epoxides, alcohols, and ketones, HMOs seem to inhibit autoxidation reactions, perhaps by reacting with peroxides or radicals. Attempts to use HMOs and metal loaded HMOs as epoxidation catalysts were unsuccessful, although their utility for this reaction was not entirely ruled out. Likewise, alcohol formation from olefins in the presence of HMO catalysts was not achieved. However, this work led to the discovery that acidified HMOs can lead to carbocation reactions of hydrocarbons such as cracking. An HMO catalyst containing Rh and Cu that promotes the reaction of {alpha}-olefins with oxygen to form methyl ketones was identified. Although the activity of the catalyst is relatively low and isomerization reactions of the olefin simultaneously occur, results indicate that these problems may be addressed by eliminating mass transfer limitations. Other suggestions for improving the catalyst are also made. 57 refs.

Miller, J.E.; Dosch, R.G.; McLaughlin, L.I. [Sandia National Labs., Albuquerque, NM (United States). Process Research Dept.

1993-07-01T23:59:59.000Z

67

Oxygen-reducing catalyst layer  

DOE Patents (OSTI)

An oxygen-reducing catalyst layer, and a method of making the oxygen-reducing catalyst layer, where the oxygen-reducing catalyst layer includes a catalytic material film disposed on a substrate with the use of physical vapor deposition and thermal treatment. The catalytic material film includes a transition metal that is substantially free of platinum. At least one of the physical vapor deposition and the thermal treatment is performed in a processing environment comprising a nitrogen-containing gas.

O' Brien, Dennis P. (Maplewood, MN); Schmoeckel, Alison K. (Stillwater, MN); Vernstrom, George D. (Cottage Grove, MN); Atanasoski, Radoslav (Edina, MN); Wood, Thomas E. (Stillwater, MN); Yang, Ruizhi (Halifax, CA); Easton, E. Bradley (Halifax, CA); Dahn, Jeffrey R. (Hubley, CA); O' Neill, David G. (Lake Elmo, MN)

2011-03-22T23:59:59.000Z

68

Less platinum means lower prices for autos | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Less platinum means lower prices for autos Less platinum means lower prices for autos Less platinum means lower prices for autos January 21, 2010 - 3:29pm Addthis Joshua DeLung You might wear a platinum wedding band, but tucked away in the guts of a car probably isn't where Americans prefer this pricey, precious metallic element to be. Luckily, researchers at 3M's Fuel Cell Component's Program in St. Paul, Minnesota have us covered. 3M has developed technology that will reduce the amount of platinum necessary in a fuel cell system by using nano-catalyst particles that actually make surface atoms more efficient at producing energy. Platinum is needed in fuel cells because no other metals are even close to being as effective at speeding up chemical reactions to make power. 3M is among a handful of fuel cell system suppliers in the U.S., and these advancements

69

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 series of Au/TiO2 catalysts were prepared from various metalorganic gold complexes. The catalytic activity and the particle size of the gold catalysts were strongly dependent on the gold complexes. The Au/TiO2 catalyst prepared from a tetranuclear gold complex showed the best performance for CO oxidation, and the average gold particle size of this catalyst was 3.1 nm. CO oxidation was also studied over Au/MgO catalysts, where the MgO supports were annealed to various temperatures between 900 and 1300 K prior to deposition of Au. A correlation was found between the activity of Au clusters for the catalytic oxidation of CO and the F-center concentration in the MgO support. In addition, the catalytic oxidation of CO was studied in a batch reactor over supported Pd/Al2O3 catalysts, a Pd(100) single crystal, as well as polycrystalline metals of rhodium, palladium, and platinum. A hyperactive state, corresponding to an oxygen covered surface, was observed at high O2/CO ratios at elevated pressures. The reaction rate at this state was significantly higher than that on CO-covered surfaces at stoichiometric conditions. The oxygen chemical potential required to achieve the hyperactive state depends on the intrinsic properties of the metal, the particle size, and the reaction temperature. A well-ordered ultra-thin titanium oxide film was synthesized on the Mo(112) surface as a model catalyst support. Two methods were used to prepare this Mo(112)- (8x2)-TiOx film, including direct growth on Mo(112) and indirect growth by deposition of Ti onto monolayer SiO2/Mo(112). The latter method was more reproducible with respect to film quality as determined by low-energy electron diffraction and scanning tunneling microscopy. The thickness of this TiOx film was one monolayer and the oxidation state of Ti was +3 as determined by Auger spectroscopy, high-resolution electron energy loss spectroscopy, and X-ray photoelectron spectroscopy.

Yan, Zhen

2007-12-01T23:59:59.000Z

70

Hydrogenation of coal liquid utilizing a metal carbonyl catalyst  

DOE Patents (OSTI)

Coal liquid having a dissolved transition metal, catalyst as a carbonyl complex such as Co.sub.2 (CO.sub.8) is hydrogenated with hydrogen gas or a hydrogen donor. A dissociating solvent contacts the coal liquid during hydrogenation to form an immiscible liquid mixture at a high carbon monoxide pressure. The dissociating solvent, e.g. ethylene glycol, is of moderate coordinating ability, while sufficiently polar to solvate the transition metal as a complex cation along with a transition metal, carbonyl anion in solution at a decreased carbon monoxide pressure. The carbon monoxide pressure is reduced and the liquids are separated to recover the hydrogenated coal liquid as product. The dissociating solvent with the catalyst in ionized form is recycled to the hydrogenation step at the elevated carbon monoxide pressure for reforming the catalyst complex within fresh coal liquid.

Feder, Harold M. (Hinsdale, IL); Rathke, Jerome W. (Bolingbrook, IL)

1979-01-01T23:59:59.000Z

71

Metal salt catalysts for enhancing hydrogen spillover  

DOE Patents (OSTI)

A composition for hydrogen storage includes a receptor, a hydrogen dissociating metal doped on the receptor, and a metal salt doped on the receptor. The hydrogen dissociating metal is configured to spill over hydrogen to the receptor, and the metal salt is configured to increase a rate of the spill over of the hydrogen to the receptor.

Yang, Ralph T; Wang, Yuhe

2013-04-23T23:59:59.000Z

72

REFORMULATION OF COAL-DERIVED TRANSPORTATION FUELS: SELECTIVE OXIDATION OF CARBON MONOXIDE ON METAL FOAM CATALYSTS  

DOE Green Energy (OSTI)

Uses for structured catalytic supports, such as ceramic straight-channel monoliths and ceramic foams, have been established for a long time. One of the most prominent examples is the washcoated ceramic monolith as a three-way catalytic converter for gasoline-powered automobiles. A distinct alternative to the ceramic monolith is the metal foam, with potential use in fuel cell-powered automobiles. The metal foams are characterized by their pores per inch (ppi) and density ({rho}). In previous research, using 5 wt% platinum (Pt) and 0.5 wt% iron (Fe) catalysts, washcoated metal foams, 5.08 cm in length and 2.54 cm in diameter, of both varying and similar ppi and {rho} were tested for their activity (X{sub CO}) and selectivity (S{sub CO}) on a CO preferential oxidation (PROX) reaction in the presence of a H{sub 2}-rich gas stream. The variances in these metal foams' activity and selectivity were much larger than expected. Other structured supports with 5 wt% Pt, 0-1 wt% Fe weight loading were also examined. A theory for this phenomenon states that even though these structured supports have a similar nominal catalyst weight loading, only a certain percentage of the Pt/Fe catalyst is exposed on the surface as an active site for CO adsorption. We will use two techniques, pulse chemisorption and temperature programmed desorption (TPD), to characterize our structured supports. Active metal count, metal dispersion, and other calculations will help clarify the causes for the activity and selectivity variations between the supports. Results on ceramic monoliths show that a higher Fe loading yields a lower dispersion, potentially because of Fe inhibition of the Pt surface for CO adsorption. This theory is used to explain the reason for activity and selectivity differences for varying ppi and {rho} metal foams; less active and selective metal foams have a lower Fe loading, which justifies their higher metal dispersion. Data on the CO desorption temperature and average metal crystallite size for TPD are also collected.

Paul Chin; George W. Roberts; James J. Spivey

2003-12-31T23:59:59.000Z

73

Coming up with platinum substitutes may be elemental  

NLE Websites -- All DOE Office Websites (Extended Search)

Coming up with platinum substitutes may be elemental Coming up with platinum substitutes may be elemental Community Connections: Our link to Northern New Mexico Communities Latest Issue:Dec. 2013 - Jan. 2014 All Issues » submit Coming up with platinum substitutes may be elemental Lab researchers are working with an abundant element to take their place: cobalt. February 1, 2013 dummy image Read our archives. Contacts Editor Linda Anderman Email Community Programs Office Kurt Steinhaus Email Initial findings by a Los Alamos team indicate that if a cobalt atom is captured within a complex molecule, it can mimic the reactivity of platinum group metals. Platinum and some related precious metals (palladium, iridium, rhodium and ruthenium) are frequently used as chemical catalysts and for countless laboratory processes. As rare metals, they are also expensive. To ensure

74

Chemical Forms and Distribution of Platinum Group Metals and Technetium During Spent Fuel Reprocessing  

SciTech Connect

Amongst the fission products present in spent nuclear fuel of Nuclear Power Plants there are considerable quantities of platinum group metals (PGMs): ruthenium, rhodium and palladium. At the same time there are considerable amounts of technetium in the spent fuel, the problem of its removal at radiochemical plants being in operation encountering serious difficulties. Increased interest in this radionuclides is due not only to its rather large yield, but to higher mobility in the environment as well. However, the peculiarities of technetium chemistry in nitric acid solutions create certain problems when trying to separate it as a single product in the course of NPP's spent fuel reprocessing. The object of this work was to conduct a comprehensive analysis of platinum group metals and technetium behavior at various stages of spent fuel reprocessing and to seek the decisions which could make it possible to separate its as a single product. The paper will report data on platinum metals (PGM) and technetium distribution in spent fuel reprocessing products. The description of various techniques for palladium recovery from differing in composition radioactive solutions arising from reprocessing is given. (authors)

Pokhitonov, Y. [V.G. Khlopin Radium Institute, St. Petersburg (Russian Federation)

2007-07-01T23:59:59.000Z

75

Metal complexes of substituted Gable porphyrins as oxidation catalysts  

DOE Patents (OSTI)

Transition metal complexes of Gable porphyrins are disclosed having two porphyrin rings connected through a linking group, and having on the porphyrin rings electron-withdrawing groups, such as halogen, nitro or cyano. These complexes are useful as catalysts for the oxidation of organic compounds, e.g. alkanes.

Lyons, J.E.; Ellis, P.E. Jr.; Wagner, R.W.

1996-01-02T23:59:59.000Z

76

Metal complexes of substituted Gable porphyrins as oxidation catalysts  

DOE Patents (OSTI)

Transition metal complexes of Gable porphyrins having two porphyrin rings connected through a linking group, and having on the porphyrin rings electron-withdrawing groups, such as halogen, nitro or cyano. These complexes are useful as catalysts for the oxidation of organic compounds, e.g. alkanes.

Lyons, James E. (Wallingford, PA); Ellis, Jr., Paul E. (Downingtown, PA); Wagner, Richard W. (Murrysville, PA)

1996-01-01T23:59:59.000Z

77

Catalyst of a metal heteropoly acid salt that is insoluble in ...  

Catalyst of a metal heteropoly acid salt that is insoluble in a polar solvent on a non-metallic porous support and method of making United States Patent

78

Metallic and bimetallic catalysts for electrochemical reduction of problematic aqueous anions.  

E-Print Network (OSTI)

??Metallic and bimetallic systems are investigated voltammetrically as possible catalysts for the electrochemical reduction of nitrate. Iindium and palladium are the most thoroughly examined metals… (more)

Mahle, Thomas

2012-01-01T23:59:59.000Z

79

Platinum Metals Rev., 2008, 52, (3), 144-154  

NLE Websites -- All DOE Office Websites (Extended Search)

Metals Rev., 2008, 52, (3), 144-154 Metals Rev., 2008, 52, (3), 144-154 144 1. Introduction Coal-fired utility boilers are the largest anthro- pogenic emitters of mercury in the United States, accounting for approximately one third of the 150 tons of mercury emitted annually (1, 2). In 2005, the U.S. Environmental Protection Agency (EPA) announced the Clean Air Mercury Rule, to limit mercury emissions from coal-fired utility boilers to 15 tons annually, approximately 30% of 1999 levels, by 2018 (3). At the time of publication (July 2008) this measure is under legal dispute. Of alter- native legislative proposals to regulate mercury along with other pollutants, most would require a 90% mercury reduction, with deadlines for control varying from 2011 to 2015. Mercury exists in three forms in coal-derived flue gas: elemental (Hg

80

REDUCTION OF NITRIC OXIDE BY CARBON MONOXIDE OVER A SILICA SUPPORTED PLATINUM CATALYST: INFRARED AND KINETIC STUDIES  

E-Print Network (OSTI)

System. • B. Procedures. Catalyst Preparation Infrared DiskPreparation. Catalyst Characterization. PreliminaryReduction by CO Over a Pt Catalyst," M.S. thesis, Department

Lorimer, D.H.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Metal catalyst technique for texturing silicon solar cells  

SciTech Connect

Textured silicon solar cells and techniques for their manufacture utilizing metal sources to catalyze formation of randomly distributed surface features such as nanoscale pyramidal and columnar structures. These structures include dimensions smaller than the wavelength of incident light, thereby resulting in a highly effective anti-reflective surface. According to the invention, metal sources present in a reactive ion etching chamber permit impurities (e.g. metal particles) to be introduced into a reactive ion etch plasma resulting in deposition of micro-masks on the surface of a substrate to be etched. Separate embodiments are disclosed including one in which the metal source includes one or more metal-coated substrates strategically positioned relative to the surface to be textured, and another in which the walls of the reaction chamber are pre-conditioned with a thin coating of metal catalyst material.

Ruby, Douglas S. (Albuquerque, NM); Zaidi, Saleem H. (Albuquerque, NM)

2001-01-01T23:59:59.000Z

82

Platinum Nanoclusters Out-Perform Single Crystals  

NLE Websites -- All DOE Office Websites (Extended Search)

Platinum Nanoclusters Out-Perform Single Platinum Nanoclusters Out-Perform Single Crystals Platinum Nanoclusters Out-Perform Single Crystals Print Wednesday, 27 October 2010 00:00 When it comes to metal catalysts, platinum is the standard. However, at about $2,000 an ounce, the high cost of the raw material presents major challenges for the future wide-scale use of platinum in fuel cells. Berkeley Lab research suggests that one possible way to meet these challenges is to think small. Researchers from Berkeley Lab's Materials Sciences Division have found that under high pressure-comparable to the pressures at which many industrial technologies operate-platinum surfaces can change their structure dramatically in response to the presence of high-coverage reactants. High-pressure scanning tunneling microscopes (STM) and ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) at ALS Beamlines 9.3.2 and 11.0.2 allowed researchers to study catalysts' structure and composition under realistic conditions.

83

Process for metallization of a substrate by curing a catalyst applied thereto  

DOE Patents (OSTI)

An improved additive process for metallization of substrates is described whereby a catalyst solution is applied to a surface of a substrate. Metallic catalytic clusters can be formed in the catalyst solution on the substrate surface by heating the substrate. Electroless plating can then deposit metal onto the portion of the substrate surface coated with catalyst solution. Additional metallization thickness can be obtained by electrolytically plating the substrate surface after the electroless plating step.

Chen, Ken S. (Albuquerque, NM); Morgan, William P. (Albuquerque, NM); Zich, John L. (Albuquerque, NM)

2002-10-08T23:59:59.000Z

84

Methanol tolerant oxygen reduction catalysts based on transition metal sulfides  

Science Conference Proceedings (OSTI)

The oxygen reduction activity and methanol tolerance of a range of transition metal sulfide electrocatalysts have been evaluated in half-cell experiments and in a liquid-feed solid polymer electrolyte direct methanol fuel cell. These catalysts were prepared in high surface area form by direct synthesis onto various surface-functionalized carbon blacks. Of the materials tested, mixed-metal catalysts based on ReRuS and MoRuS were observed to give the best oxygen reduction activities. In addition, significant increases in performance were observed when employing sulfur-functionalized carbon black, which were attributed to the preferential deposition of active Ru sites in the catalyst-preparation process. Although the intrinsic activity of the best material tested, namely, Mo{sub 2}Ru{sub 5}S{sub 5} on sulfur-treated XC-72, was lower than Pt (by ca. 1545 mV throughout the entire polarization curve), its activity relative to Pt increased significantly in methanol-contaminated electrolytes. This was due to methanol oxidation side reactions reducing the net activity of the Pt, especially at low overpotentials.

Reeve, R.W.; Christensen, P.A.; Hamnett, A.; Haydock, S.A.; Roy, S.C. [Univ. of Newcastle, Newcastle upon Tyne (United Kingdom). Dept. of Chemistry

1998-10-01T23:59:59.000Z

85

Development of Metal Substrate for Denox Catalysts and Particulate Trap  

DOE Green Energy (OSTI)

The objective of this project was to develop advanced metallic catalyst substrate materials and designs for use in off-highway applications. The new materials and designs will be used as catalyst substrates and diesel particulate traps. They will increase durability, reduce flow resistance, decrease time to light-off, and reduce cost relative to cordierite substrates. Metallic catalyst substrates are used extensively for diesel oxidation catalysts and have the potential to be used in other catalytic systems for diesel engines. Metallic substrates have many advantages over ceramic materials including improved durability and resistance to thermal shock and vibration. However, the cost is generally higher than cordierite. The most common foil material used for metallic substrates is FeCr Alloy, which is expensive and has temperature capabilities beyond what is necessary for diesel applications. The first task in the project was Identification and Testing of New Materials. In this task, several materials were analyzed to determine if a low cost substitute for FeCr Alloy was available or could be developed. Two materials were identified as having lower cost while showing no decrease in mechanical properties or oxidation resistance at the application temperatures. Also, the ability to fabricate these materials into a finished substrate was not compromised, and the ability to washcoat these materials was satisfactory. Therefore, both candidate materials were recommended for cost savings depending on which would be less expensive in production quantities. The second task dealt with the use of novel flow designs to improve the converter efficiency while possibly decreasing the size of the converter to reduce cost even more. A non-linear flow path was simulated to determine if there would be an increase in efficiency. From there, small samples were produced for bench testing. Bench tests showed that the use of non-linear channels significantly reduced the light-off temperature for diesel oxidation catalytic converters. Finally, the third task was to implement these materials and designs into a full-size converter. Hot shake testing of 13-inch diameter straight channel substrates showed no significant difference in durability between the current material and the two proposed materials. At the time that this program ended, preparations were being made for full-scale emissions testing of the new design converter for comparison to a traditional straight channel with equal catalyst loading.

Pollard, Michael; Habeger, Craig; Frary, Megan; Haines, Scott; Fluharty, Amy; Dakhoul, Youssef; Carr, Michael; Park, Paul; Stefanick, Matthew; DaCosta, Herbert; Balmer-Millar, M Lou; Readey, Michael; McCluskey, Philip

2005-12-31T23:59:59.000Z

86

Experimental Study of In Situ Combustion with Tetralin and Metallic Catalysts.  

E-Print Network (OSTI)

??Experimental studies showed the feasibility of adding metallic catalysts and tetralin for the upgrade and increased recovery of heavy oil during the in situ combustion… (more)

Palmer-Ikuku, Emuobonuvie

2010-01-01T23:59:59.000Z

87

Method for hydrogen production and metal winning, and a catalyst/cocatalyst composition useful therefor  

DOE Patents (OSTI)

A catalyst/cocatalyst/organics composition of matter is useful in electrolytically producing hydrogen or electrowinning metals. Use of the catalyst/cocatalyst/organics composition causes the anode potential and the energy required for the reaction to decrease. An electrolyte, including the catalyst/cocatalyst composition, and a reaction medium composition further including organic material are also described.

Dhooge, Patrick M. (Corrales, NM)

1987-10-13T23:59:59.000Z

88

Method of inducing surface ensembles on a metal catalyst  

DOE Green Energy (OSTI)

A method of inducing surface ensembles on a transition metal catalyst used in the conversion of a reactant gas or gas mixture, such as carbon monoxide and hydrogen into hydrocarbons (the Fischer-Tropsch reaction) is disclosed which comprises adding a Lewis base to the syngas (CO+H.sub.2) mixture before reaction takes place. The formation of surface ensembles in this manner restricts the number and types of reaction pathways which will be utilized, thus greatly narrowing the product distribution and maximizing the efficiency of the Fischer-Tropsch reaction. Similarly, amines may also be produced by the conversion of reactant gas or gases, such as nitrogen, hydrogen, or hydrocarbon constituents.

Miller, Steven S. (Morgantown, WV)

1989-01-01T23:59:59.000Z

89

Method of inducing surface ensembles on a metal catalyst  

DOE Patents (OSTI)

A method of inducing surface ensembles on a transition metal catalyst used in the conversion of a reactant gas or gas mixture, such as carbon monoxide and hydrogen into hydrocarbons (the Fischer-Tropsch reaction) is disclosed which comprises adding a Lewis base to the syngas (CO + H/sub 2/) mixture before reaction takes place. The formation of surface ensembles in this manner restricts the number and types of reaction pathways which will be utilized, thus greatly narrowing the product distribution and maximizing the efficiency of the Fischer-Tropsch reaction. Similarly, amines may also be produced by the conversion of reactant gas or gases, such as nitrogen, hydrogen, or hydrocarbon constituents.

Miller, S.S.

1987-10-02T23:59:59.000Z

90

Outlooks of HLW Partitioning Technologies Usage for Recovering of Platinum Metals from Spent Fuel  

Science Conference Proceedings (OSTI)

The existing practice of management of high level waste (HLW) generated by NPPs, call for a task of selective separation of the most dangerous long-lived radionuclides with the purpose of their subsequent immobilization and disposal. HLW partitioning allows to reduce substantially the cost of vitrified product storage owing to isolation of the most dangerous radionuclides, such as transplutonium elements (TPE) into separate fractions of small volumes, intended for ultimate storage. By now numerous investigations on partitioning of HLW of various composition have been carried out in many countries and a lot of processes permitting to recover cesium, strontium, TPE and rare earth elements (REE) have been already tested. Apart from enumerated radionuclides, a fair quantity of palladium and rhodium presents in spent fuel, but the problem of these elements recovery has not yet been decided at the operating radiochemical plants. A negative effect of platinum group metals (PGM) occurrence is determined by the formation of separate metal phase, which not only worsens the conditions of glass-melting but also shortens considerably the service life of the equipment. At the same time, the exhaustion of PGMs natural resources may finally lead to such a growth of their costs that the spent nuclear fuel would became a substituting source of these elements industrial production. Allowing above mentioned, it is of interest to develop the technique for ''reactor'' palladium and rhodium recovery process which would be compatible with HLW partitioning and could be realized using the same facilities. In the report the data on platinum metals distribution in spent fuel reprocessing products and the several flowsheets for palladium separation from HLW are presented.

Pokhitonov, Y. A.; Estimantovskiy, V.; Romanovski, v.; Zatsev, B.; Todd, T.

2003-02-24T23:59:59.000Z

91

SLAC National Accelerator Laboratory - SSRL Contributes to Platinum...  

NLE Websites -- All DOE Office Websites (Extended Search)

joined forces to investigate a catalyst that promotes energy-releasing reactions in fuel cells. They discovered that the catalyst, made of ultrathin platinum layers grown on...

92

Autothermal reforming catalyst having perovskite structure  

DOE Patents (OSTI)

The invention addressed two critical issues in fuel processing for fuel cell application, i.e. catalyst cost and operating stability. The existing state-of-the-art fuel reforming catalyst uses Rh and platinum supported over refractory oxide which add significant cost to the fuel cell system. Supported metals agglomerate under elevated temperature during reforming and decrease the catalyst activity. The catalyst is a perovskite oxide or a Ruddlesden-Popper type oxide containing rare-earth elements, catalytically active firs row transition metal elements, and stabilizing elements, such that the catalyst is a single phase in high temperature oxidizing conditions and maintains a primarily perovskite or Ruddlesden-Popper structure under high temperature reducing conditions. The catalyst can also contain alkaline earth dopants, which enhance the catalytic activity of the catalyst, but do not compromise the stability of the perovskite structure.

Krumpel, Michael (Naperville, IL); Liu, Di-Jia (Naperville, IL)

2009-03-24T23:59:59.000Z

93

Oxidation catalysts comprising metal exchanged hexaaluminate wherein the metal is Sr, Pd, La, and/or Mn  

DOE Patents (OSTI)

The present invention provides metal-exchanged hexaaluminate catalysts that exhibit good catalytic activity and/or stability at high temperatures for extended periods with retention of activity as combustion catalysts, and more generally as oxidation catalysts, that make them eminently suitable for use in methane combustion, particularly for use in natural gas fired gas turbines. The hexaaluminate catalysts of this invention are of particular interest for methane combustion processes for minimization of the generation of undesired levels (less than about 10 ppm) of NOx species. Metal exchanged hexaaluminate oxidation catalysts are also useful for oxidation of volatile organic compounds (VOC), particularly hydrocarbons. Metal exchanged hexaaluminate oxidation catalysts are further useful for partial oxidation, particularly at high temperatures, of reduced species, particularly hydrocarbons (alkanes and alkenes).

Wickham, David (Boulder, CO); Cook, Ronald (Lakewood, CO)

2008-10-28T23:59:59.000Z

94

Bioreductive recovery of platinum group metals by the metal-ion ...  

Science Conference Proceedings (OSTI)

The metal ion-reducing bacterium, Shewanella algae, was found to exhibit the ability to reduce and deposit the PGM ions (Pd(II), Pt(IV), Rh(III)) into metal ...

95

CATALYSTS NHI Thermochemical Systems FY 2009 Year-End Report  

DOE Green Energy (OSTI)

Fiscal Year 2009 work in the Catalysts project focused on advanced catalysts for the decomposition of sulfuric acid, a reaction common to both the Sulfur-Iodine (S-I) cycle and the Hybrid Sulfur cycle. Prior years’ effort in this project has found that although platinum supported on titanium oxide will be an acceptable catalyst for sulfuric acid decomposition in the integrated laboratory scale (ILS) project, the material has short comings, including significant cost and high deactivation rates due to sintering and platinum evaporation. For pilot and larger scale systems, the catalyst stability needs to be improved significantly. In Fiscal Year 2008 it was found that at atmospheric pressure, deactivation rates of a 1 wt% platinum catalyst could be reduced by 300% by adding either 0.3 wt% iridium (Ir) or 0.3 wt% ruthenium (Ru) to the catalyst. In Fiscal Year 2009, work focused on examining the platinum group metal catalysts activity and stability at elevated pressures. In addition, simple and complex metal oxides are known to catalyze the sulfuric acid decomposition reaction. These metal oxides could offer activities comparable to platinum but at significantly reduced cost. Thus a second focus for Fiscal Year 2009 was to explore metal oxide catalysts for the sulfuric acid decomposition reaction. In Fiscal Year 2007 several commercial activated carbons had been identified for the HI decomposition reaction; a reaction specific to the S-I cycle. Those materials should be acceptable for the pilot scale project. The activated carbon catalysts have some disadvantages including low activity at the lower range of reactor operating temperature (350 to 400°C) and a propensity to generate carbon monoxide in the presence of water that could contaminate the hydrogen product, but due to limited funding, this area had low priority in Fiscal Year 2009. Fiscal Year 2009 catalyst work included five tasks: development, and testing of stabilized platinum based H2SO4 catalysts, development and testing of metal oxide based H2SO4 catalysts, support of the ILS for catalyst studies, conducting a long term catalyst stability test at anticipated operating temperatures and pressures, and developing capabilities for conducting pressurized catalyst tests.

Daniel M. Ginosar

2009-09-01T23:59:59.000Z

96

Method for producing hydrocarbon fuels from heavy polynuclear hydrocarbons by use of molten metal halide catalyst  

DOE Patents (OSTI)

In a process for hydrocracking heavy polynuclear carbonaceous feedstocks to produce lighter hydrocarbon fuels by contacting the heavy feedstocks with hydrogen in the presence of a molten metal halide catalyst, thereafter separating at least a substantial portion of the carbonaceous material associated with the reaction mixture from the spent molten metal halide and thereafter regenerating the metal halide catalyst, an improvement comprising contacting the spent molten metal halide catalyst after removal of a major portion of the carbonaceous material therefrom with an additional quantity of hydrogen is disclosed.

Gorin, Everett (San Rafael, CA)

1979-01-01T23:59:59.000Z

97

Effect of Graphitic Content on Carbon Supported Catalyst Performance  

DOE Green Energy (OSTI)

The effect of graphitic content on carbon supported platinum catalysts was investigated in order to investigate its influence on catalyst performance. Four catalysts of varying surface areas and graphitic content were analyzed using XPS, HREELS, and tested using RDE experiments. The catalysts were also heat treated at 150 C and 100%RH as means to uniformly age them. The heat treated samples were analyzed using the same methods to determine what changes had occurred due to this aging process. When compared to the BOL catalysts, heat treated catalysts displayed increased graphitic carbon and platinum metallic content, however they also showed depressed catalytic activity. The primary cause is still under investigation, though it is believed to be related to loss of amorphous carbon content.

A. Patel; K. Artyushkova; P. Atanassov; David Harvey; M. Dutta; V. Colbow; S. Wessel

2011-07-01T23:59:59.000Z

98

Catalysts for oxidation of mercury in flue gas  

DOE Patents (OSTI)

Two new classes of catalysts for the removal of heavy metal contaminants, especially mercury (Hg) from effluent gases. Both of these classes of catalysts are excellent absorbers of HCl and Cl.sub.2 present in effluent gases. This adsorption of oxidizing agents aids in the oxidation of heavy metal contaminants. The catalysts remove mercury by oxidizing the Hg into mercury (II) moieties. For one class of catalysts, the active component is selected from the group consisting of iridium (Ir) and iridum-platinum (Ir/Pt) alloys. The Ir and Ir/Pt alloy catalysts are especially corrosion resistant. For the other class of catalyst, the active component is partially combusted coal or "Thief" carbon impregnated with Cl.sub.2. Untreated Thief carbon catalyst can be self-activating in the presence of effluent gas streams. The Thief carbon catalyst is disposable by means of capture from the effluent gas stream in a particulate collection device (PCD).

Granite, Evan J. (Wexford, PA); Pennline, Henry W. (Bethel Park, PA)

2010-08-17T23:59:59.000Z

99

Novel NIST Process Is a Low-Cost Route to Ultrathin Platinum ...  

Science Conference Proceedings (OSTI)

... Under a high driving voltage, platinum in solution (bound to four ... Platinum is a widely used industrial catalyst—in automobile catalytic converters ...

2012-12-12T23:59:59.000Z

100

An exploratory program for using hydrous metal oxide ion exchangers as Fischer-Tropsch catalysts  

SciTech Connect

The purpose of this program is to investigate the potential of hydrous metal oxide (HMO) ion exchangers, invented at Sandia National Laboratories, as Fischer-Tropsch (F-T) catalysts. Metals known to be active in F-T synthesis (e.g. Fe, Co) were ion exchanged on hydrous metal oxide supports. Although HMO catalysts based on Zr, Nb, and Ta have been investigated in direct coal liquefaction studies, this effect focused on formulations based on the hydrous titanium oxide (HTO) system. The program has the goals of developing a catalyst with (1) high activity, (2) selectively to fuel range or other useful products, and (3) better properties for use in slurry reactors. The program has three main tasks: (1) catalyst synthesis, to develop methods for preparing catalysts having desirable F-T properties, (2) characterization, to investigate catalysts proving to have desirable properties by a variety of analytical techniques to determine correlations between activity and material properties and (3) testing to determine activity and selectivity of catalysts. This paper discussed results of activity testing of Ruhrchemie catalyst and some catalyst formulations prepared using ion exchange on hydrous titanium oxide and precipitation. For example, at 250{degree}C the Ruhrchemie catalyst converts {approximately}50% of the syngas feed to reaction products. In comparison, iron catalysts prepared by ion exchange and precipitation had conversions ranging from 20 to 50% over a temperature range of 250 to 275{degree}C of the syngas feed. In addition, results are Auger surface analysis of Ruhrchemie catalyst are presented. 6 refs., 2 figs., 2 tabs.

Lynch, A.W.; Dosch, R.G.; Sault, A.G.

1990-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Pt–metal oxide aerogel catalysts: X-ray photoemission investigation  

Science Conference Proceedings (OSTI)

X-ray photoemission spectroscopy was used to study Pt–metal oxide aerogel catalysts that have been developed to respond to increased NO x emissions of lean-burn engines. Lean-burn engines

A. J. Nelson; John G. Reynolds; R. D. Sanner; P. R. Coronado; L. M. Hair

2001-01-01T23:59:59.000Z

102

Metal/ceria water-gas shift catalysts for automotive polymer electrolyte fuel cell system.  

DOE Green Energy (OSTI)

Polymer electrolyte fuel cell (PEFC) systems are a leading candidate for replacing the internal combustion engine in light duty vehicles. One method of generating the hydrogen necessary for the PEFC is reforming a liquid fuel, such as methanol or gasoline, via partial oxidation, steam reforming, or autothermal reforming (a combination of partial oxidation and steam reforming). The H{sub 2}-rich reformate can contain as much as 10% carbon monoxide. Carbon monoxide has been shown to poison the platinum-based anode catalyst at concentrations as low as 10 ppm,1 necessitating removal of CO to this level before passing the reformate to the fuel cell stack. The water-gas shift (WGS) reaction, CO + H{sub 2}O {rightleftharpoons} CO{sub 2} + H{sub 2}, is used to convert the bulk of the reformate CO to CO{sub 2}. Industrially, the WGS reaction is conducted over two catalysts, which operate in different temperature regimes. One catalyst is a FeCr mixed oxide, which operates at 350-450 C and is termed the high-temperature shift (HTS) catalyst. The second catalyst is a CuZn mixed oxide, which operates at 200-250 C and is termed the low-temperature shift (LTS) catalyst. Although these two catalysts are used industrially in the production of H{sub 2} for ammonia synthesis, they have major drawbacks that make them unsuitable for transportation applications. Both the LTS and the HTS catalysts must first be ''activated'' before being used. For example, the copper in the copper oxide/zinc oxide LTS catalyst must first be reduced to elemental copper in situ before it becomes active for the WGS reaction. This reduction reaction is exothermic and must be carried out under well- controlled conditions using a dilute hydrogen stream (1 vol% H{sub 2}) to prevent high catalyst temperatures, which can result in sintering (agglomeration) of the copper particles and loss of active surface area for the WGS reaction. Also, once the catalyst has been activated by reduction, it must be protected from exposure to ambient air to prevent re-oxidation of the copper. The activated catalyst must also be protected from the condensation of liquids, for example, during start-up or transient operation. For these reasons, a more thermally rugged catalyst is needed which has sufficient activity to operate at the low temperatures that are thermodynamically necessary to achieve low CO concentrations.

Myers, D. J.; Krebs, J. F.; Carter, J. D.; Kumar, R.; Krumpelt, M.

2002-01-11T23:59:59.000Z

103

Platinum-Alloy Cathode Catalyst Degradation in Proton Exchange Membrane Fuel Cells: Nanometer-Scale Compositional and Morphological Changes  

E-Print Network (OSTI)

Electrochemical measurements showed an ?75% Pt surface area loss and an ?40% specific activity loss for a membrane electrode assembly (MEA) cathode with acid-treated “Pt[subscript 3]Co ” catalyst particles in a H[subscript ...

Chen, Shuo

104

Photo-oxidation catalysts  

DOE Patents (OSTI)

Photo-oxidation catalysts and methods for cleaning a metal-based catalyst are disclosed. An exemplary catalyst system implementing a photo-oxidation catalyst may comprise a metal-based catalyst, and a photo-oxidation catalyst for cleaning the metal-based catalyst in the presence of light. The exposure to light enables the photo-oxidation catalyst to substantially oxidize absorbed contaminants and reduce accumulation of the contaminants on the metal-based catalyst. Applications are also disclosed.

Pitts, J. Roland (Lakewood, CO); Liu, Ping (Irvine, CA); Smith, R. Davis (Golden, CO)

2009-07-14T23:59:59.000Z

105

Colloid Science of Metal Nanoparticle Catalysts in 2D and 3D Structures. Challenges of Nucleation, Growth, Composition, Particle Shape, Size Control and their Influence on Activity and Selectivity  

SciTech Connect

Recent breakthroughs in synthesis in nanosciences have achieved control of size and shapes of nanoparticles that are relevant for catalyst design. In this article, we review the advance of synthesis of nanoparticles, fabrication of two and three dimensional model catalyst system, characterization, and studies of activity and selectivity. The ability to synthesize monodispersed platinum and rhodium nanoparticles in the 1-10 nm range permitted us to study the influence of composition, structure, and dynamic properties of monodispersed metal nanoparticle on chemical reactivity and selectivity. We review the importance of size and shape of nanoparticles to determine the reaction selectivity in multi-path reactions. The influence of metal-support interaction has been studied by probing the hot electron flows through the metal-oxide interface in catalytic nanodiodes. Novel designs of nanoparticle catalytic systems are discussed.

Somorjai, Gabor A.; Park, Jeong Y.

2008-02-13T23:59:59.000Z

106

Hollow Nanoparticles as Active and Durable Catalysts - Energy ...  

Platinum is an excellent catalyst for many reactions. However, it is also very expensive. The catalytic activity per gram of platinum can be increased by using a ...

107

BSA 07-17: Synthesis of Metal-Metal Oxide Catalysts and ...  

Tags: catalyst, fuel cell. Find a Technology. Search our technologies by categories or by keywords. Search ...

108

Evaluation of coal minerals and metal residues as coal-liquefaction catalysts. Final report  

DOE Green Energy (OSTI)

The catalytic activity of various minerals, metallic wastes, and transition metals was investigated in the liquefaction of various coals. The effects of coal type, process variables, coal cleaning, catalyst addition mode, solvent quality, and solvent modification on coal conversion and oil production were also studied. Coal conversion and oil production improved significantly by the addition of pyrite, reduced pyrite, speculite, red mud, flue dust, zinc sulfide, and various transition metal compounds. Impregnation and molecular dispersion of iron gave higher oil production than particulate incorporation of iron. However, the mode of molybdenum addition was inconsequential. Oil production increased considerably both by adding a stoichiometric mixture of iron oxide and pyrite and by simultaneous impregnation of coal with iron and molybdenum. Hydrogenation activity of disposable catalysts decreased sharply in the presence of nitrogen compounds. The removal of heteroatoms from process solvent improved thermal as well as catalytic coal liquefaction. The improvement in oil production was very dramatic with a catalyst.

Garg, D.; Givens, E. N.; Schweighardt, F. K.; Tarrer, A. R.; Guin, J. A.; Curtis, C. W.; Huang, W. J.; Shridharani, K.; Clinton, J. H.

1982-02-01T23:59:59.000Z

109

The Use of Soluble Polyolefins as Supports for Transition Metal Catalysts  

E-Print Network (OSTI)

The use of polymer supports for transition metal catalysts are very important and useful in synthetic organic chemistry as they make possible the separation and isolation of catalysts and products quite easy. These polymer-bound ligands/catalysts/reagents can, often, be recovered and recycled numerous times and typically yield products in high purity, negating the need for further purification steps (i.e. column chromatography). Because of this, interest in these systems has garnered international attention in the scientific community as being “Green”. Historically, insoluble, polymer-supports (i.e. Merrifield resin) were used to develop recoverable catalysts. This has the advantage of easy separation and isolation from products after a reaction; because of their insolubility, such supported catalysts can be easily removed by gravity filtration. However, these catalysts often have relatively poor reactivity and selectivity when compared to homogeneous catalysts. Because of this disadvantage, our lab has had interest in the development of soluble polymer-supports for transition metal catalysts. We have developed several separation methods for these soluble polymer-bound catalysts. These include thermomorphic liquid/liquid and solid/liquid as well as latent biphasic liquid/liquid separation techniques. This dissertation describes the use of both, latent biphasic liquid/liquid separation systems and thermomorphic solid/liquid separation systems. In order to perform a latent biphasic iii liquid/liquid separation, a polymer-bound catalyst must have a very high selectivity for one liquid phase over the other. Our lab has pioneered the use of polyisobutylene (PIB) oligomers as supports for transition metal catalysts. Previous work has shown that these oligomers are > 99.96 % phase selectively soluble in nonpolar solvents. This has allowed us to prepare PIB-supported salen Cr(III) complexes that can be used in a latent biphasic liquid/liquid solvent system. The synthesis of these complexes is quite straightforward and such species can be characterized using solution state 1H and 13C NMR spectroscopy. Also, these complexes can be used to catalyze the ring opening of meso epoxides with azidotrimethylsilane (TMS-N3) and can be recovered and recycled up to 6 times, with no loss in catalytic activity. To perform a thermomorphic solid/liquid separation, a polymer-bound catalyst that is completely insoluble at room temperature but soluble upon heating must be used. Our lab has pioneered the use of polyethylene oligomers (PEOlig) as supports for transition metal catalysts. Such PEOlig-supported catalysts are able perform homogeneous catalytic reactions at elevated temperatures (ca. 65 ?C), but, upon cooling, precipitate out of solution as solids while the products stay in solution. This process allows for the easy separation of a solid catalyst from the product solution. Described herein, is the development of PEOlig-supported salen-Cr(III) complexes and PEOlig-supported NHC-Ru complexes. The preparation of these complexes is also straightforward and such species can be characterized using solution state variable temperature (VT) 1H and 13C NMR spectroscopy. In the case of the PEOlig-supported salen-Cr(III) complex, it was found to be a recoverable/recyclable catalyst for the ring opening of epoxides with TMS-N3 and could be reused 6 times with no loss in activity. The PE-supported NHC-Ru complex was able to be used as a recyclable ring closing metathesis (RCM) catalyst and could be used up to 10 times.

Hobbs, Christopher Eugene

2011-08-01T23:59:59.000Z

110

Applications of hydrogenation and dehydrogenation on noble metal catalysts  

E-Print Network (OSTI)

Hydrogenation and dehydrogenation on Pd- and Pt- catalysts are encountered in many industrial hydrocarbon processes. The present work considers the development of catalysts and their kinetic modeling along a general and rigorous approach. The first part deals with the kinetics of selective hydrogenation, more particularly of the C3 cut of a thermal cracking unit for olefins production. The kinetics of the gas phase selective hydrogenation of methyl-acetylene (MA) and propadiene (PD) over a Pd/?-alumina catalyst were investigated in a fixed bed tubular reactor at temperatures 60 - 80 oC and a pressure of 20 bara. Hougen-Watson type kinetic equations were derived. The formation of higher oligomers slowly deactivated the catalyst. The effect of the deactivating agent on the rates of the main reactions as well as on the deactivating agent formation itself was expressed in terms of a deactivation function multiplying the corresponding rates at zero deactivation. Then, the kinetic model was plugged into the reactor model to simulate an industrial adiabatic reactor. In the second part the production of hydrogen from hydrocarbons was investigated. In both cyclohexane and decalin dehydrogenations, conversions higher than 98% could be obtained over Pt/?-alumina catalyst at temperature of 320 and 340 oC, respectively, with no apparent deactivation for 30 h and with co-feed of H2 in the feed. Except for H2 and trace amounts of side cracking products, less than 0.01%, benzene was the only dehydrogenated product in cyclohexane dehydrogenation. In the case of decalin dehydrogenation, partially dehydrogenated product, tetralin, was also formed with selectivity lower than 5%, depending on operating conditions. A rigorous Hougen-Watson type kinetic model was derived, which accounted for both the dehydrogenation of cis- and trans- decalin in the feed and also the isomerization of the two isomers. Jet A is the logic fuel in the battlefields. The dehydrogenation of Jet A can produce H2 for military fuel cell application. Although the H2 production is lower than that of steam/autothermal reforming, it eliminates the needs of high temperature and product separation operation.

Wang, Bo

2007-08-01T23:59:59.000Z

111

Rhodium Catalysts in the Oxidation of CO by O2 and NO: Shape, Composition, and Hot Electron Generation  

E-Print Network (OSTI)

ACTIVITY OF PLATINUM CATALYSTS. Journal of Catalysis 1966,SUPPORTED BIMETALLIC-CLUSTER CATALYSTS. Journal of Catalysisnanoparticle heterogeneous catalyst. Chem. Commun. 1999, (

Renzas, James Russell

2010-01-01T23:59:59.000Z

112

Highly Dispersed Metal Catalyst - Home - Energy Innovation Portal  

Method for full dispersion of active metals into a high surface area of support to promote efficiency Scientists at the Savannah River National Laboratory have ...

113

DIRECT DECOMPOSITION OF METHANE TO HYDROGEN ON METAL LOADED ZEOLITE CATALYST  

DOE Green Energy (OSTI)

The manufacture of hydrogen from natural gas is essential for the production of ultra clean transportation fuels. Not only is hydrogen necessary to upgrade low quality crude oils to high-quality, low sulfur ultra clean transportation fuels, hydrogen could eventually replace gasoline and diesel as the ultra clean transportation fuel of the future. Currently, refinery hydrogen is produced through the steam reforming of natural gas. Although efficient, the process is responsible for a significant portion of refinery CO2 emissions. This project is examining the direct catalytic decomposition of methane as an alternative to steam reforming. The energy required to produce one mole of hydrogen is slightly lower and the process does not require water-gas-shift or pressure-swing adsorption units. The decomposition process does not produce CO2 emissions and the product is not contaminated with CO -- a poison for PEM fuel cells. In this work we examined the direct catalytic decomposition of methane over a metal modified zeolite catalyst and the recovery of catalyst activity by calcination. A favorable production of hydrogen was obtained, when compared with previously reported nickel-zeolite supported catalysts. Reaction temperature had a strong influence on catalyst activity and on the type of carbon deposits. The catalyst utilized at 873 and 973 K could be regenerated without any significant loss of activity, however the catalyst utilized at 1073 K showed some loss of activity after regeneration.

Lucia M. Petkovic; Daniel M. Ginosar; Kyle C. Burch; Harry W. Rollins

2005-08-01T23:59:59.000Z

114

Ruthenium-Platinum Thin Film Analysis Using Grazing Incidence X-ray Diffraction  

DOE Green Energy (OSTI)

Ruthenium (Ru, Z = 44) is a Platinum Group Metal that has a standard hexagonal close packed (HCP) crystalline structure. Platinum (Pt, Z = 78) has a face-centered cubic (FCC) crystalline structure. When these metals are co-sputtered onto a silicon substrate, creating a few nm-thin film, they form an alloy with a combination of HCP and FCC structure. Direct methanol fuel cells rely on an anode catalyst to draw hydrogen from liquid methanol. Highly efficient fuel cells based on polymer electrolyte catalysts, known as proton-exchange membrane fuel cells, have been developed, but require large amounts of a costly platinum catalyst. Thin-film nanostructure bimetallic alloys have been produced to reduce the amount of expensive Platinum needed for catalysis, and also to improve the electrochemical properties of the catalyst. Supported RuPt particles have been shown to have superior activity as anode catalysts for methanol electro-oxidation and demonstrate an improvement in resistance to poisoning in comparison to unalloyed Pt. The percentage of Ruthenium in a RuPt thin film and the process by which the alloy is produced will dictate the crystalline structure, and thus the electrochemical properties of the film. Pure Ruthenium, Pure Platinum, and eight intermediate samples at differing percent composition of Ruthenium were characterized by their X-ray diffraction patterns. The incident beam is from the Stanford Synchrotron Radiation Laboratory beam and operates at approximately a 1.4 Angstrom wavelength. The results show that 0% Ru through 46.17% Ru exhibit a majority FCC structure, 56.07% Ru and 60.61% Ru are mixed phase, and from 67.03% Ru through 100% Ru, the samples exhibit a HCP structure.

Jones, L.

2004-09-03T23:59:59.000Z

115

Syntheses and applications of soluble polyisobutylene (PIB)-supported transition metal catalysts  

E-Print Network (OSTI)

Soluble polymer supports facilitate the recovery and recycling of expensive transition metal complexes. Recently, polyisobutylene (PIB) oligomers have been found to be suitable polymer supports for the recovery of a variety of transition metal catalysts using liquid/liquid biphasic separations after a homogeneous reaction. Our work has shown that PIB-supported Ni(II) and Co(II) ?-diketonates prepared from commercially available vinyl terminated PIB oligomers possess catalytic activity like that of their low molecular weight analogs in Mukaiyama epoxidation of olefins. Carboxylic acid terminated PIB derivatives can act as carboxylate ligands for Rh(II) cyclopropanation catalysts. An achiral PIB-supported Rh(II) carboxylate catalyst showed good activity in cyclopropanation of styrene in hydrocarbon solvents, and could be easily recycled nine times by a post reaction extraction. Further application of PIB supports in asymmetric cyclopropanation reactions were investigated using PIBsupported arenesulfonyl Rh(II) prolinates derived from L-proline as examples. The PIBsupported chiral Rh carboxylates demonstrated moderate activity and were recovered and reused for four to five cycles. The prolinate catalyst prepared from PIB-anisole also showed encouraging enantioselectivity and about 8% ee and 13% ee were observed on trans- and cis-cyclopropanation product respectively. Finally, PIB oligomers can be modified in a multi step sequence to prepare PIBsupported chiral bisoxazolines that can in turn be used to prepare active, recyclable PIBsupported Cu(I) bisoxazoline complexes for olefin cyclopropanation. These chiral copper catalysts showed moderate catalytic activity and good stereoselectivity in cyclopropanation of styrene. A chiral ligand prepared from D-phenylglycinol provided the most effective stereo control and gave the trans- and cis-cyclopropanation product in 94% ee and 68% ee respectively. All three PIB-supported chiral bisoxazoline-Cu(I) catalysts could be reused five to six times.

Tian, Jianhua

2008-12-01T23:59:59.000Z

116

Use of noble metals in automobile exhaust catalysts  

SciTech Connect

This is a review of recent literature involving laboratory work on catalytic reactions of interest in automobile exhaust purification. The review is concerned with the noble metals Pt, Pd, and Rh, the oxidation of CO and hydrocarbons, the reduction of NO, and the water-gas-shift and steam-re-forming reactions. Current thoughts are given about the mechanisms of these reactions, the dependence of the reaction rates on particle size, when known, and the role of the impurity SO/sub 2/. The current opinion that alloy formation between the noble metals is detrimental and segregation beneficial is supported by literature references.

Kummer, J.T.

1986-09-25T23:59:59.000Z

117

Process for carbonaceous material conversion and recovery of alkali metal catalyst constituents held by ion exchange sites in conversion residue  

DOE Patents (OSTI)

In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered for the particles by contacting or washing them with an aqueous solution containing calcium or magnesium ions in an alkali metal recovery zone at a low temperature, preferably below about 249.degree. F. During the washing or leaching process, the calcium or magnesium ions displace alkali metal ions held by ion exchange sites in the particles thereby liberating the ions and producing an aqueous effluent containing alkali metal constituents. The aqueous effluent from the alkali metal recovery zone is then recycled to the conversion process where the alkali metal constituents serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst.

Sharp, David W. (Seabrook, TX)

1980-01-01T23:59:59.000Z

118

Science Magazine Highlight: Moving Towards Near Zero Platinum Fuel Cells Webinar  

NLE Websites -- All DOE Office Websites (Extended Search)

Magazine Highlight: Magazine Highlight: Moving Towards Near Zero Platinum Fuel Cells Piotr Zelenay Co-Authors Gang Wu, Hoon Chung, Christina Johnston, Patrick Turner, Zhongfen Ding, Jerzy Chlistunoff, Nate Mack, Mark Nelson Los Alamos National Laboratory Los Alamos, New Mexico 87545, USA 1 1 Fuel Cell Technologies Program Webinar - April 25, 2011 DOE Fuel Cell Technologies Webinar - April 25, 2011 Outline * Introduction: ─ rationale ─ recent developments in non-precious metal oxygen reduction reaction (ORR) catalysis ( ) y * Low-temperature Oxygen Reduction Reaction (ORR) catalysts (PPy-Co-C) * Catalysts obtained by heat treatment of organic and transition- metal precursors: ─ polyaniline-derived catalysts as a best combination of activity polyaniline derived catalysts as a best combination of activity

119

Transition metal oxides deposited on rhodium and platinum: Surface chemistry and catalysis  

DOE Green Energy (OSTI)

The surface chemistry and catalytic reactivity of transition metal oxides deposited on Rh and Pt substrates has been examined in order to establish the role of oxide-metal interactions in influencing catalytic activity. The oxides investigated included titanium oxide (TiOx), vanadium oxide (VOx), iron oxide (FeOx), zirconium oxide (ZrOx), niobium oxide (NbOx), tantalum oxide (TaOx), and tungsten oxide (WOx). The techniques used to characterize the sample included AES, XPS, LEED, TPD, ISS, and STM. After characterization of the surface in UHV, the sample was enclosed in an atmospheric reaction cell to measure the influence of the oxide deposits on the catalytic activity of the pure metal for CO and CO{sub 2} hydrogenation. The oxide deposits were found to strongly enhance the reactivity of the Rh foil. The rates of methane formation were promoted by up to 15 fold with the maximum in rate enhancement occurring at oxide coverages of approximately 0.5 ML. TiOx TaOx, and NbOx were the most effective promoters and were stable in the highest oxidation states during both reactions (compared to VOx, WOx, and FeOx). The trend in promoter effectiveness was attributed to the direct relationship between oxidation state and Lewis acidity. Bonding at the metal oxide/metal interface between the oxygen end of adsorbed CO and the Lewis acidic oxide was postulated to facilitate C-O bond dissociation and subsequent hydrogenation. 192 refs.

Boffa, A.B. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States). Materials Sciences Div.

1994-07-01T23:59:59.000Z

120

Carbon monoxide oxidation over three different states of copper: Development of a model metal oxide catalyst  

SciTech Connect

Carbon monoxide oxidation was performed over the three different oxidation states of copper -- metallic (Cu), copper (I) oxide (Cu{sub 2}O), and copper (II) oxide (CuO) as a test case for developing a model metal oxide catalyst amenable to study by the methods of modern surface science and catalysis. Copper was deposited and oxidized on oxidized supports of aluminum, silicon, molybdenum, tantalum, stainless steel, and iron as well as on graphite. The catalytic activity was found to decrease with increasing oxidation state (Cu > Cu{sub 2}O > CuO) and the activation energy increased with increasing oxidation state (Cu, 9 kcal/mol < Cu{sub 2}O, 14 kcal/mol < CuO, 17 kcal/mol). Reaction mechanisms were determined for the different oxidation states. Lastly, NO reduction by CO was studied. A Cu and CuO catalyst were exposed to an equal mixture of CO and NO at 300--350 C to observe the production of N{sub 2} and CO{sub 2}. At the end of each reaction, the catalyst was found to be Cu{sub 2}O. There is a need to study the kinetics of this reaction over the different oxidation states of copper.

Jernigan, G.G. [California Univ., Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States). Materials and Chemical Sciences Div.

1994-10-01T23:59:59.000Z

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121

The Science And Engineering of Duralbe Ultralow PGM Catalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Fuel Cells and Infrastructure Technologies Fuel Cells and Infrastructure Technologies 2009 Kickoff Meeting The Science And Engineering of Durable Ultralow PGM Catalysts Eric Brosha, Neil Henson and Fernando Garzon (PI) LANL 1 Los Alamos National Laboratory (lead participant) Ballard Power Systems (BPS) University of California Riverside (UCR) University of New Mexico (UNM) Oak Ridge National Laboratory (ORNL) *Development of durable, high mass activity Platinum Group Metal cathode catalysts *Elucidation of the fundamental relationships between PGM catalyst shape, particle size and activity *Optimization of the cathode electrode layer to maximize the performance of PGM catalysts *Understanding the performance degradation mechanisms of high mass activity cathode catalysts *Development and testing of fuel cells using ultra-low loading high activity

122

It's Elemental - The Element Platinum  

NLE Websites -- All DOE Office Websites (Extended Search)

Iridium Iridium Previous Element (Iridium) The Periodic Table of Elements Next Element (Gold) Gold The Element Platinum [Click for Isotope Data] 78 Pt Platinum 195.084 Atomic Number: 78 Atomic Weight: 195.084 Melting Point: 2041.55 K (1768.4°C or 3215.1°F) Boiling Point: 4098 K (3825°C or 6917°F) Density: 21.46 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: 10 Group Name: none What's in a name? From the Spainsh word for silver, platina. Say what? Platinum is pronounced as PLAT-en-em. History and Uses: Used by the pre-Columbian Indians of South America, platinum wasn't noticed by western scientists until 1735. Platinum can occur free in nature and is sometimes found in deposits of gold-bearing sands, primarily those found in

123

Activation of Noble Metals on Metal-Carbide Surfaces: Novel Catalysts for CO Oxidation, Desulfurization and Hydrogenation Reactions  

Science Conference Proceedings (OSTI)

This perspective article focuses on the physical and chemical properties of highly active catalysts for CO oxidation, desulfurization and hydrogenation reactions generated by depositing noble metals on metal-carbide surfaces. To rationalize structure-reactivity relationships for these novel catalysts, well-defined systems are required. High-resolution photoemission, scanning tunneling microscopy (STM) and first-principles periodic density-functional (DF) calculations have been used to study the interaction of metals of Groups 9, 10 and 11 with MC(001) (M = Ti, Zr, V, Mo) surfaces. DF calculations give adsorption energies that range from 2 eV (Cu, Ag, Au) to 6 eV (Co, Rh, Ir). STM images show that Au, Cu, Ni and Pt grow on the carbide substrates forming two-dimensional islands at very low coverage, and three-dimensional islands at medium and large coverages. In many systems, the results of DF calculations point to the preferential formation of admetal-C bonds with significant electronic perturbations in the admetal. TiC(001) and ZrC(001) transfer some electron density to the admetals facilitating bonding of the adatom with electron-acceptor molecules (CO, O{sub 2}, C{sub 2}H{sub 4}, SO{sub 2}, thiophene, etc.). For example, the Cu/TiC(001) and Au/TiC(001) systems are able to cleave both S-O bonds of SO{sub 2} at a temperature as low as 150 K, displaying a reactivity much larger than that of TiC(001) or extended surfaces of bulk copper and gold. At temperatures below 200 K, Au/TiC is able to dissociate O{sub 2} and perform the 2CO + O{sub 2} {yields} 2CO{sub 2} reaction. Furthermore, in spite of the very poor hydrodesulfurization performance of TiC(001) or Au(111), a Au/TiC(001) surface displays an activity for the hydrodesulfurization of thiophene higher than that of conventional Ni/MoS{sub x} catalysts. In general, the Au/TiC system is more chemically active than systems generated by depositing Au nanoparticles on oxide surfaces. Thus, metal carbides are excellent supports for enhancing the chemical reactivity of noble metals.

Rodriguez J. A.; Illas, F.

2012-01-01T23:59:59.000Z

124

Direct methanol fuel cells at reduced catalyst loadings  

DOE Green Energy (OSTI)

We focus in this paper on the reduction of catalyst loading in direct methanol fuel cells currently under development at Los Alamos National Laboratory. Based on single-cell DMFC testing, we discuss performance vs. catalyst loading trade-offs and demonstrate optimization of the anode performance. We also show test data for a short five-cell DMFC stack with the average total platinum loading of 0.53 mg cm{sup -2} and compare performance of this stack with the performance of a single direct methanol fuel cell using similar total amount of precious metal.

Zelenay, P. (Piotr); Guyon, F. (Francois); Gottesfeld, Shimshon

2001-01-01T23:59:59.000Z

125

DIRECT METHANOL FUEL CELLS AT REDUCED CATALYST LOADINGS  

DOE Green Energy (OSTI)

We focus in this paper on the reduction of catalyst loading in direct methanol fuel cells currently under development at Los Alamos National Laboratory. Based on single-cell DMFC testing, we discuss performance vs. catalyst loading trade-offs and demonstrate optimization of the anode performance. We also show test data for a short five-cell DMFC stack with the average total platinum loading of 0.53 mg cm{sup {minus}2} and compare performance of this stack with the performance of a single direct methanol fuel cell using similar total amount of precious metal.

P. ZELENAY; F. GUYON; SM. GOTTESFELD

2001-05-01T23:59:59.000Z

126

Role of metal-support interactions on the activity of Pt and Rh catalysts for reforming methane and butane.  

DOE Green Energy (OSTI)

For residential fuel cell systems, reforming of natural gas is one option being considered for providing the H{sub 2} necessary for the fuel cell to operate. Industrially, natural gas is reformed using Ni-based catalysts supported on an alumina substrate, which has been modified to inhibit coke formation. At Argonne National Laboratory, we have developed a new family of catalysts derived from solid oxide fuel cell technology for reforming hydrocarbon fuels to generate H{sub 2}. These catalysts consist of a transition metal supported on an oxide-ion-conducting substrate, such as ceria, that has been doped with a small amount of a non-reducible element, such as gadolinium, samarium, or zirconium. Unlike alumina, the oxide-ion-conducting substrate has been shown to induce strong metal-support interactions. Metal-support interactions are known to play an important role in influencing the catalytic activity of many metals supported on oxide supports. Based on results from temperature-programmed reduction/oxidation and kinetic reaction studies, this paper discusses the role of the metal and the substrate in the metal-support interactions, and how these interactions influence the activity and the selectivity of the catalyst in reforming methane and butane to hydrogen for use in fuel cell power systems.

Rossignol, C.; Krause, T.; Krumpelt, M.

2002-01-11T23:59:59.000Z

127

Catalyst activator  

DOE Patents (OSTI)

A catalyst activator particularly adapted for use in the activation of metal complexes of metals of Group 3-10 for polymerization of ethylenically unsaturated polymerizable monomers, especially olefins, comprising two Group 13 metal or metalloid atoms and a ligand structure including at least one bridging group connecting ligands on the two Group 13 metal or metalloid atoms.

McAdon, Mark H. (Midland, MI); Nickias, Peter N. (Midland, MI); Marks, Tobin J. (Evanston, IL); Schwartz, David J. (Lake Jackson, TX)

2001-01-01T23:59:59.000Z

128

Breakthrough Research on Platinum-Nickel Alloys  

NLE Websites -- All DOE Office Websites (Extended Search)

Breakthrough Research on Platinum-Nickel Alloys Print Breakthrough Research on Platinum-Nickel Alloys Print Two out of three of the kinetic barriers to the practical use of polymer electrolyte membrane (PEM) hydrogen fuel cells in automobiles have been breached: the impractically high amount of extra energy needed for the oxidation reduction reaction (ORR) on the catalyst and the loss of catalytic surface areas available for ORR. Using a combination of probes and calculations, a group of scientists has demonstrated that the Pt3Ni(111) alloy is ten times more active for ORR than the corresponding Pt(111) surface and ninety times more active than the current state-of-the-art Pt/C catalysts used in existing PEM fuel cells. This new variation of the platinum-nickel alloy is the most active oxygen-reducing catalyst ever reported.

129

Breakthrough Research on Platinum-Nickel Alloys  

NLE Websites -- All DOE Office Websites (Extended Search)

Breakthrough Research on Breakthrough Research on Platinum-Nickel Alloys Breakthrough Research on Platinum-Nickel Alloys Print Wednesday, 28 February 2007 00:00 Two out of three of the kinetic barriers to the practical use of polymer electrolyte membrane (PEM) hydrogen fuel cells in automobiles have been breached: the impractically high amount of extra energy needed for the oxidation reduction reaction (ORR) on the catalyst and the loss of catalytic surface areas available for ORR. Using a combination of probes and calculations, a group of scientists has demonstrated that the Pt3Ni(111) alloy is ten times more active for ORR than the corresponding Pt(111) surface and ninety times more active than the current state-of-the-art Pt/C catalysts used in existing PEM fuel cells. This new variation of the platinum-nickel alloy is the most active oxygen-reducing catalyst ever reported.

130

Catalysis of methanol-air mixture using platinum nanoparticles for microscale combustion  

Science Conference Proceedings (OSTI)

High surface area, active catalysts containing dispersed catalytic platinum nanoparticles (dp ?11.6 nm) on a cordierite substrate were fabricated and characterized using TEM, XRD, and SEM. The catalyst activity was evaluated for ...

James R. Applegate; Howard Pearlman; Smitesh D. Bakrania

2012-01-01T23:59:59.000Z

131

Catalytic reforming with a platinum group and phosphorus-containing composition  

Science Conference Proceedings (OSTI)

A new catalyst composition for converting hydrocarbons is disclosed. Also disclosed is a method for making the catalyst. The catalyst comprises a platinum group component and a phosphorous component with a porous support material. The catalyst is made by compositing a platinum group component with a porous support material and then contacting that composite with phosphorus or a compound of phosphorus. In a preferred embodiment of the invention a catalyst comprising platinum, phosphorus and chlorine with alumina is utilized in the catalytic reforming of hydrocarbons boiling in the gasoline range to produce a high octane reformate suitable for gasoline blending or a high aromatics content reformate suitable as a petrochemical feedstock.

Antos, G. J.; Chao, T.-H.

1984-11-20T23:59:59.000Z

132

REFORMULATION OF COAL-DERIVED TRANSPORTATION FUELS: SELECTIVE OXIDATION OF CARBON MONOXIDE ON METAL FOAM CATALYSTS  

DOE Green Energy (OSTI)

Several different catalytic reactions must be carried out in order to convert hydrocarbons (or alcohols) into hydrogen for use as a fuel for polyelectrolyte membrane (PEM) fuel cells. Each reaction in the fuel-processing sequence has a different set of characteristics, which influences the type of catalyst support that should be used for that particular reaction. A wide range of supports are being evaluated for the various reactions in the fuel-processing scheme, including porous and non-porous particles, ceramic and metal straight-channel monoliths, and ceramic and metal monolithic foams. These different types of support have distinctly different transport characteristics. The best choice of support for a given reaction will depend on the design constraints for the system, e.g., allowable pressure drop, and on the characteristics of the reaction for which the catalyst is being designed. Three of the most important reaction characteristics are the intrinsic reaction rate, the exothermicity/endothermicity of the reaction, and the nature of the reaction network, e.g., whether more than one reaction takes place and, in the case of multiple reactions, the configuration of the network. Isotopic transient kinetic analysis was used to study the surface intermediates. The preferential oxidation of low concentrations of carbon monoxide in the presence of high concentrations of hydrogen (PROX) is an important final step in most fuel processor designs. Data on the behavior of straight-channel monoliths and foam monolith supports will be presented to illustrate some of the factors involved in choosing a support for this reaction.

Mr. Paul Chin; Dr. Xiaolei Sun; Professor George W. Roberts; Professor James J. Spivey; Mr. Amornmart Sirijarhuphan; Dr. James G. Goodwin, Jr.; Dr. Richard W. Rice

2002-12-31T23:59:59.000Z

133

Toward Photochemical Water Splitting Using Band-Gap-Narrowed Semiconductors and Transition-Metal Based Molecular Catalysts  

DOE Green Energy (OSTI)

We are carrying out coordinated theoretical and experimental studies of toward photochemical water splitting using band-gap-narrowed semiconductors (BGNSCs) with attached multi-electron molecular water oxidation and hydrogen production catalysts. We focus on the coupling between the materials properties and the H{sub 2}O redox chemistry, with an emphasis on attaining a fundamental understanding of the individual elementary steps in the following four processes: (1) Light-harvesting and charge-separation of stable oxide or oxide-derived semiconductors for solar-driven water splitting, including the discovery and characterization of the behavior of such materials at the aqueous interface; (2) The catalysis of the four-electron water oxidation by dinuclear hydroxo transition-metal complexes with quinonoid ligands, and the rational search for improved catalysts; (3) Transfer of the design principles learned from the elucidation of the DuBois-type hydrogenase model catalysts in acetonitrile to the rational design of two-electron hydrogen production catalysts for aqueous solution; (4) Combining these three elements to examine the function of oxidation catalysts on BGNSC photoanode surfaces and hydrogen production catalysts on cathode surfaces at the aqueous interface to understand the challenges to the efficient coupling of the materials functions.

Muckerman,J.T.; Rodriguez, J.A.; Fujita, E.

2009-06-07T23:59:59.000Z

134

Methanol-tolerant cathode catalyst composite for direct methanol fuel cells  

oxidation catalyst adjacent the anode electrode and the membrane, an oxidant reduction catalyst adjacent the cathode electrode and the membrane, comprises an oxidant reduction catalyst layer of a platinum-chromium alloy so that oxidation at the ...

135

METHOD OF PURIFYING CATALYSTS  

DOE Patents (OSTI)

It has been fuund that the presence of chlorine as an impurity adversely affects the performance of finely divided platinum catalysts such as are used in the isotopic exchange process for the production of beavy water. This chlorine impurity may be removed from these catalysts by treating the catalyst at an elevated temperature with dry hydrogen and then with wet hydrogen, having a hydrogen-water vapor volume of about 8: 1. This alternate treatment by dry hydrogen and wet hydrogen is continued until the chlorine is largely removed from the catalyst.

Joris, G.G.

1958-09-01T23:59:59.000Z

136

Methanol electrochemical conversion to formaldehyde over bulk metal and supported catalysts.  

E-Print Network (OSTI)

??The electrochemical oxidation of 1.0 M CH3OH in 0.1 M H2SO4 over different types of platinum-ruthenium (PtRu) materials was investigated. Focus was on the determination… (more)

Islam, Mohsina

2006-01-01T23:59:59.000Z

137

Fundamental investigations of supported monometallic and bimetallic catalysts by proton magnetic resonance spectroscopy  

DOE Green Energy (OSTI)

Proton magnetic resonance spectroscopy, or nuclear magnetic resonance (NMR) of hydrogen, has been applied to investigate silica-supported Group VIII monometallic and Group VIII-Group IB bimetallic catalysts and alumina- and silica-supported platinum-rhenium bimetallic catalysts. Two adsorbed states of hydrogen, i.e., irreversible and reversible hydrogen, on the surfaces of monometallic Ru, Pt, and Cu particles and bimetallic Ru-Group Ib, Pt-Group Ib, and Pt-Re particles were observed directly via proton NMR. The same amounts of the irreversible hydrogen adsorbed on pure Ru catalysts were measured by both proton NMR and the volumetric technique. The electronic environments on surfaces of monometallic catalysts are sensitive to changes in metal dispersion, state of adsorbed hydrogen, and residual chlorine. Surface compositions for the Ru--Cu and Pt--Cu bimetallic catalysts were determined by NMR of adsorbed hydrogen. 297 refs., 96 figs., 19 tabs.

Wu, Xi.

1990-09-21T23:59:59.000Z

138

Development of Ultra-Low Platinum Alloy Cathode Catalyst for PEM Fuel Cells - DOE Hydrogen and Fuel Cells Program FY 2012 Annual Progress Report  

NLE Websites -- All DOE Office Websites (Extended Search)

3 3 FY 2012 Annual Progress Report DOE Hydrogen and Fuel Cells Program Branko N. Popov University of South Carolina (USC) 301 Main Street Columbia, SC 29208 Phone: (803) 777-7314 Email: popov@cec.sc.edu DOE Managers HQ: Donna Lee Ho Phone: (202) 586-8000 Email: Donna.Ho@ee.doe.gov GO: David Peterson Phone: (720) 356-1747 Email: David.Peterson@go.doe.gov Technical Advisor Thomas Benjamin Phone: (630) 252-1632 Email: benjamin@anl.gov Contract Number: DE-EE0000460 Subcontractor: Dr. Hansung Kim (Co-PI) Yonsei University, S. Korea. Project Start Date: September 1, 2010 Project End Date: May 31, 2014 Objectives Develop low-cost and durable hybrid cathode catalyst * (HCC). Develop Pt alloy/activated graphitic carbon catalyst. * Develop corrosion resistant supports. *

139

Method for producing hydrocarbon fuels and fuel gas from heavy polynuclear hydrocarbons by the use of molten metal halide catalysts  

DOE Patents (OSTI)

In a process for hydrocracking heavy polynuclear carbonaceous feedstocks to produce lighter hydrocarbon fuels by contacting the heavy feedstocks with hydrogen in the presence of a molten metal halide catalyst in a hydrocracking zone, thereafter separating at least a major portion of the lighter hydrocarbon fuels from the spent molten metal halide and thereafter regenerating the spent molten metal halide by incinerating the spent molten metal halide by combustion of carbon and sulfur compounds in the spent molten metal halide in an incineration zone, the improvement comprising: (a) contacting the heavy feedstocks and hydrogen in the presence of the molten metal halide in the hydrocracking zone at reaction conditions effective to convert from about 60 to about 90 weight percent of the feedstock to lighter hydrocarbon fuels; (b) separating at least a major portion of the lighter hydrocarbon fuels from the spent molten metal halide; (c) contacting the spent molten metal halide with oxygen in a liquid phase gasification zone at a temperature and pressure sufficient to vaporize from about 25 to about 75 weight percent of the spent metal halide, the oxygen being introduced in an amount sufficient to remove from about 60 to about 90 weight percent of the carbon contained in the spent molten metal halide to produce a fuel gas and regenerated metal halide; and (d) incinerating the spent molten metal halide by combusting carbon and sulfur compounds contained therein.

Gorin, Everett (San Rafael, CA)

1979-01-01T23:59:59.000Z

140

Composite catalysts supported on modified carbon substrates and methods of making the same  

DOE Patents (OSTI)

A method of producing a composite carbon catalyst is generally disclosed. The method includes oxidizing a carbon precursor (e.g., carbon black). Optionally, nitrogen functional groups can be added to the oxidized carbon precursor. Then, the oxidized carbon precursor is refluxed with a non-platinum transitional metal precursor in a solution. Finally, the solution is pyrolyzed at a temperature of at least about 500.degree. C.

Popov, Branko N. (Columbia, SC); Subramanian, Nalini (Kennesaw, GA); Colon-Mercado, Hector R. (Columbia, SC)

2009-11-17T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Catalytic reforming catalyst  

Science Conference Proceedings (OSTI)

An improved catalyst, having a reduced fouling rate when used in a catalytic reforming process, said catalyst comprising platinum disposed on an alumina support wherein the alumina support is obtained by removing water from aluminum hydroxide produced as a by-product from a ziegler higher alcohol synthesis reaction, and wherein the alumina is calcined at a temperature of 1100-1400/sup 0/F so as to have a surface area of 165 to 215 square meters per gram.

Buss, W.C.; Kluksdahl, H.E.

1980-12-09T23:59:59.000Z

142

Catalysts for hydrocarbon conversion  

Science Conference Proceedings (OSTI)

Catalyst, particularly useful in catalytic reforming and for producing highly pure aromatic hydrocarbons, comprising an alumina carrier and containing, expressed in proportion of the weight of the alumina carrier: 005 to 1% of platinum 01 to 4% of gallium, indium or thallium 01 to 2% of tungsten, and 1 to 10% of halogen.

Le P. J.; Malmaison, R.; Marcilly, C.; Martino, G.; Miquel, J.

1980-08-12T23:59:59.000Z

143

Oxyhydrochlorination catalyst  

DOE Patents (OSTI)

An improved catalyst and method for the oxyhydrochlorination of methane is disclosed. The catalyst includes a pyrogenic porous support on which is layered as active material, cobalt chloride in major proportion, and minor proportions of an alkali metal chloride and of a rare earth chloride. On contact of the catalyst with a gas flow of methane, HCl and oxygen, more than 60% of the methane is converted and of that converted more than 40% occurs as monochloromethane. Advantageously, the monochloromethane can be used to produce gasoline boiling range hydrocarbons with the recycle of HCl for further reaction. This catalyst is also of value for the production of formic acid as are analogous catalysts with lead, silver or nickel chlorides substituted for the cobalt chloride.

Taylor, Charles E. (Pittsburgh, PA); Noceti, Richard P. (Pittsburgh, PA)

1992-01-01T23:59:59.000Z

144

Methods of making textured catalysts  

SciTech Connect

A textured catalyst having a hydrothermally-stable support, a metal oxide and a catalyst component is described. Methods of conducting aqueous phase reactions that are catalyzed by a textured catalyst are also described. The invention also provides methods of making textured catalysts and methods of making chemical products using a textured catalyst.

Werpy, Todd (West Richland, WA); Frye, Jr., John G. (Richland, WA); Wang, Yong (Richland, WA); Zacher, Alan H. (Kennewick, WA)

2010-08-17T23:59:59.000Z

145

Catalyst for the production of hydrocarbons from the synthesis gas  

SciTech Connect

This patent describes a catalyst for the production of hydrocarbons from the synthesis gas, which comprises the combination of an iron-containing Fisher-Tropsch catalyst, a zeolite and at least one metal selected from the group consisting of ruthenium, rhodium, platinum, palladium, irridium, cobalt and molybdenum. The metal supported upon the iron-containing Fischer-Tropsch catalyst or supported upon a mixture of the iron-containing Fischer-Tropsch catalyst and the zeolite. The iron in terms of iron oxide in the iron-containing Fischer-Tropsch catalyst is present in an amount of 5 to 80% by weight, based on the combined weight of the iron oxide and zeolite. The metal is present in amounts of 0.3 to 5% by weight, based upon the combined weight of the iron oxide and the zeolite. The zeolite is selected from the group consisting of zeolites having a pore size of 5 o 9 A and a silica to alumina mole ratio of at least 12 is described.

Koikeda, M.; Suzuki, T.; Munemura, K.; Nishimoto, Y.; Imai, T.

1986-11-11T23:59:59.000Z

146

Early transition metal catalysts for the living polymerization of olefins and alkynes  

E-Print Network (OSTI)

Zirconium and Hafnium Ziegler-Natta catalysts containing the [(2,6- C12C6H3NCH2CH2)2NMe]2- ([ArciN2NMe]2') ligand were prepared and employed in the polymerization of 1-hexene. Hafnium Ziegler-Natta catalysts containing the ...

Adamchuk, Jennifer

2006-01-01T23:59:59.000Z

147

Hydrocarbon synthesis catalyst and method of preparation  

DOE Patents (OSTI)

A catalyst for the synthesis of hydrocarbons from carbon monoxide and hydrogen composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants. The catalyst is preferably used in dilute slurry form, which is desirable from a heat transfer standpoint.

Sapienza, Richard S. (Shoreham, NY); Sansone, Michael J. (Summit, NJ); Slegeir, William A. R. (Hampton Bays, NY)

1983-08-02T23:59:59.000Z

148

Process of making supported catalyst  

DOE Patents (OSTI)

Oxide supported metal catalysts have an additional metal present in intimate association with the metal catalyst to enhance catalytic activity. In a preferred mode, iridium or another Group VIII metal catalyst is supported on a titania, alumina, tungsten oxide, silica, or composite oxide support. Aluminum ions are readsorbed onto the support and catalyst, and reduced during calcination. The aluminum can be added as aluminum nitrate to the iridium impregnate solution, e.g. chloroiridic acid.

Schwarz, James A. (Fayetteville, NY); Subramanian, Somasundaram (Melvindale, MI)

1992-01-01T23:59:59.000Z

149

Electrochemical catalyst recovery method  

DOE Patents (OSTI)

A method of recovering catalyst material from latent catalyst material solids includes: a) combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form a mixture; b) electrochemically oxidizing the redox material within the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material; c) reacting the oxidant with the latent catalyst material to oxidize the latent catalyst material into at least one oxidized catalyst species which is soluble within the mixture and to reduce the oxidant back into dissolved redox material; and d) recovering catalyst material from the oxidized catalyst species of the mixture. The invention is expected to be particularly useful in recovering spent catalyst material from petroleum hydroprocessing reaction waste products having adhered sulfides, carbon, hydrocarbons, and undesired metals, and as well as in other industrial applications.

Silva, Laura J. (Richland, WA); Bray, Lane A. (Richland, WA)

1995-01-01T23:59:59.000Z

150

Electrochemical catalyst recovery method  

DOE Patents (OSTI)

A method of recovering catalyst material from latent catalyst material solids includes: (a) combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form a mixture; (b) electrochemically oxidizing the redox material within the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material; (c) reacting the oxidant with the latent catalyst material to oxidize the latent catalyst material into at least one oxidized catalyst species which is soluble within the mixture and to reduce the oxidant back into dissolved redox material; and (d) recovering catalyst material from the oxidized catalyst species of the mixture. The invention is expected to be particularly useful in recovering spent catalyst material from petroleum hydroprocessing reaction waste products having adhered sulfides, carbon, hydrocarbons, and undesired metals, and as well as in other industrial applications. 3 figs.

Silva, L.J.; Bray, L.A.

1995-05-30T23:59:59.000Z

151

Tuning the Metal-Adsorbate Chemical Bond through the Ligand Effect on  

NLE Websites -- All DOE Office Websites (Extended Search)

Tuning the Metal-Adsorbate Chemical Bond through the Ligand Effect on Tuning the Metal-Adsorbate Chemical Bond through the Ligand Effect on Platinum Subsurface Alloys Tuesday, July 31, 2012 The ability to design and control the activities of transition metal catalysts, which are scarce in nature and thus expensive, has been of great importance to the development of economical industrial and energy-saving processes. Over the years several methods have been suggested, especially for processes using platinum, which is the most active metal catalyst for many important reactions, including the reduction of oxygen in fuel cells. Figure 1. Figure 1. Schematic representation of Pt subsurface alloys and corresponding shifts in Pt d-band center. Tuning chemical functionality by implementing a ligand effect - in other words, by changing the atomic nearest neighbor environment - is a

152

High Energy Resolution Fluorescence Detection X-Ray Absorption Spectroscopy: Detection of Adsorption Sites in Supported Metal Catalysts  

Science Conference Proceedings (OSTI)

High energy resolution fluorescence detection (HERFD) X-ray adsorption spectroscopy (XAS) is demonstrated as a new tool to identify the geometry of metal adsorption sites and the orbitals involved in bonding. The type of CO adsorption site on a nanoparticular Pt-Al2O3 catalyst is determined. The orbitals involved in the Pt - CO bonding are identified using theoretical FEFF8.0 calculations. In situ application of HERFD XAS is applicable to a large number of catalytic systems and will provide fundamental insights in structure - performance relationships.

Tromp, Moniek [University of Southampton, School of Chemistry, Highfield, Southampton, SO17 1BJ (United Kingdom); Bokhoven, Jeroen A. van [Institute for chemical and bioengineering ETH Zurich (Switzerland); Safonova, Olga V.; Glatzel, Pieter [ESRF, Grenoble (France); Groot, Frank M. F. de [Utrecht University, Utrecht (Netherlands); Evans, John [University of Southampton, School of Chemistry, Highfield, Southampton, SO17 1BJ (United Kingdom); Diamond Light Source, Didcot (United Kingdom)

2007-02-02T23:59:59.000Z

153

Method for hydrocracking a heavy polynuclear hydrocarbonaceous feedstock in the presence of a molten metal halide catalyst  

DOE Patents (OSTI)

A method for hydrocracking a heavy polynuclear hydrocarbonaceous feedstock to produce lighter hydrocarbon fuels by contacting the feedstock with hydrogen in the presence of a molten metal halide catalyst, the method comprising: mixing the feedstock with a heavy naphtha fraction which has an initial boiling point from about 100.degree. to about 160.degree. C. with a boiling point difference between the initial boiling point and the final boiling point of no more than about 50.degree. C. to produce a mixture; thereafter contacting the mixture with partially spent molten metal halide and hydrogen under temperature and pressure conditions so that the temperature is near the critical temperature of the heavy naphtha fraction; separating at least a portion of the heavy naphtha fraction and lighter hydrocarbon fuels from the partially spent molten metal halide, unreacted feedstock and reaction products; thereafter contacting the partially spent molten metal halide, unreacted feedstock and reaction products with hydrogen and fresh molten metal halide in a hydrocracking zone to produce additional lighter hydrocarbon fuels and separating at least a major portion of the lighter hydrocarbon fuels from the spent molten metal halide.

Gorin, Everett (San Rafael, CA)

1981-01-01T23:59:59.000Z

154

Recent Advances in Developing Platinum Monolayer Electrocatalysts for the O2 Reduction Reaction  

DOE Green Energy (OSTI)

For Pt, the best single-element catalyst for many reactions, the question of content and loading is exceedingly important because of its price and availability. Using platinum as a fuel-cell catalyst in automotive applications will cause an unquantifiable increase in the demand for this metal. This big obstacle for using fuel cells in electric cars must be solved by decreasing the content of Pt, which is a great challenge of electrocatalysis Over the last several years we inaugurated a new class of electrocatalysts for the oxygen reduction reaction (ORR) based on a monolayer of Pt deposited on metal or alloy carbon-supported nanoparticles. The possibility of decreasing the Pt content in the ORR catalysts down to a monolayer level has a considerable importance because this reaction requires high loadings due to its slow kinetics. The Pt-monolayer approach has several unique features and some of them are: high Pt utilization, enhanced (or decreased) activity, enhanced stability, and direct activity correlations. The synthesis of Pt monolayer (ML) electrocatalysts was facilitated by our new synthesis method which allowed us to deposit a monolayer of Pt on various metals, or alloy nanoparticles [1, 2] for the cathode electrocatalyst. In this synthesis approach Pt is laid down by the galvanically displacing a Cu monolayer, which was deposited at underpotentials in a monolayer-limited reaction on appropriate metal substrate, with Pt after immersing the electrode in a K{sub 2}PtCl{sub 4} solution.

Vukmirovic,M.B.; Sasaki, K.; Zhou, W.-P.; Li, M.; Liu, P.; Wang, J.X.; Adzic, R.R.

2008-09-15T23:59:59.000Z

155

Method and system for the combination of non-thermal plasma and metal/metal oxide doped .gamma.-alumina catalysts for diesel engine exhaust aftertreatment system  

DOE Patents (OSTI)

The present disclosure pertains to a system and method for treatment of oxygen rich exhaust and more specifically to a method and system that combines non-thermal plasma with a metal doped .gamma.-alumina catalyst. Current catalyst systems for the treatment of oxygen rich exhaust are capable of achieving only approximately 7 to 12% NO.sub.x reduction as a passive system and only 25 40% reduction when a supplemental hydrocarbon reductant is injected into the exhaust stream. It has been found that treatment of an oxygen rich exhaust initially with a non-thermal plasma and followed by subsequent treatment with a metal doped .gamma.-alumina prepared by the sol gel method is capable of increasing the NO.sub.x reduction to a level of approximately 90% in the absence of SO.sub.2 and 80% in the presence of 20 ppm of SO.sub.2. Especially useful metals have been found to be indium, gallium, and tin.

Aardahl, Christopher L. (Richland, WA); Balmer-Miller, Mari Lou (West Richland, WA); Chanda, Ashok (Peoria, IL); Habeger, Craig F. (West Richland, WA); Koshkarian, Kent A. (Peoria, IL); Park, Paul W. (Peoria, IL)

2006-07-25T23:59:59.000Z

156

DOE Award No. DE-FC36-03GO13108 NOVEL NON-PRECIOUS METAL CATALYSTS FOR PEMFC: CATALYST SELECTION THROUGH MOLECULAR MODELING AND DURABILITY STUDIES Final Report (September 2003 – October 2008)  

Science Conference Proceedings (OSTI)

The objective of this project is to develop novel non-precious metal electrocatalysts for oxygen reduction reaction (ORR), and demonstrate the potential of the catalysts to perform at least as good as conventional Pt catalysts currently in use in polymer electrolyte membrane fuel cell (PEMFC) with a cost at least 50 % less than a target of 0.2 g (Pt loading)/peak kW and with durability > 2,000 h operation with less than 10 % power degradation. A novel nitrogen-modified carbon-based catalyst was obtained by modifying carbon black with nitrogen-containing organic precursor in the absence of transition metal precursor. The catalyst shows the onset potential of approximately 0.76 V (NHE) for ORR and the amount of H2O2 of approximately 3% at 0.5 V (NHE). Furthermore, a carbon composite catalyst was achieved through the high-temperature pyrolysis of the precursors of transition metal (Co and Fe) and nitrogen supported on the nitrogen-modified carbon-based catalyst, followed by chemical post-treatment. This catalyst showed an onset potential for ORR as high as 0.87 V (NHE), and generated less than 1 % of H2O2. The PEM fuel cell exhibited a current density of 2.3 A cm-2 at 0.2 V for a catalyst loading of 6.0 mg cm-2. No significant performance degradation was observed for 480 h continuous operation. The characterization studies indicated that the metal-nitrogen chelate complexes decompose at the temperatures above 800 oC. During the pyrolysis, the transition metals facilitate the incorporation of pyridinic and graphitic nitrogen groups into the carbon matrix, and the carbon surface modified with nitrogen is active for ORR. In order to elucidate the role of transition metal precursor played in the formation of active sites in the non-precious metal catalysts, a novel ruthenium-based chelate (RuNx) catalyst was synthesized by using RuCl3 and propylene diammine as the Ru and N precursors, respectively, followed by high-temperature pyrolysis. This catalyst exhibited comparable catalytic activity and selectivity for ORR as the Pt catalyst. A theoretical analysis is made of the four-electron reduction reaction of oxygen to water over the mixed anion and cation (202) surface of pentlandite structure Co9Se8, one of several selenide phases. Reversible potentials for forming adsorbed reaction intermediates in acid are predicted using adsorption energies calculated with the Vienna ab initio simulation program (VASP) and the known bulk solution values together in a linear Gibbs energy relationship. The effect of hydrophobic and structural properties of a single/dual-layer cathode gas diffusion layer on mass transport in PEM fuel cells was studied using an analytical expression. The simulations indicated that liquid water transport at the cathode is controlled by the fraction of hydrophilic surface and the average pore diameter in the cathode gas diffusion layer. The optimized hydrophobicity and pore geometry in a dual-layer cathode GDL leads to an effective water management, and enhances the oxygen diffusion kinetics.

Branko N. Popov

2009-03-03T23:59:59.000Z

157

DOE Award No. DE-FC36-03GO13108 NOVEL NON-PRECIOUS METAL CATALYSTS FOR PEMFC: CATALYST SELECTION THROUGH MOLECULAR MODELING AND DURABILITY STUDIES Final Report (September 2003 – October 2008)  

Science Conference Proceedings (OSTI)

The objective of this project is to develop novel non-precious metal electrocatalysts for oxygen reduction reaction (ORR), and demonstrate the potential of the catalysts to perform at least as good as conventional Pt catalysts currently in use in polymer electrolyte membrane fuel cell (PEMFC) with a cost at least 50 % less than a target of 0.2 g (Pt loading)/peak kW and with durability > 2,000 h operation with less than 10 % power degradation. A novel nitrogen-modified carbon-based catalyst was obtained by modifying carbon black with nitrogen-containing organic precursor in the absence of transition metal precursor. The catalyst shows the onset potential of approximately 0.76 V (NHE) for ORR and the amount of H2O2 of approximately 3% at 0.5 V (NHE). Furthermore, a carbon composite catalyst was achieved through the high-temperature pyrolysis of the precursors of transition metal (Co and Fe) and nitrogen supported on the nitrogen-modified carbon-based catalyst, followed by chemical post-treatment. This catalyst showed an onset potential for ORR as high as 0.87 V (NHE), and generated less than 1 % of H2O2. The PEM fuel cell exhibited a current density of 2.3 A cm-2 at 0.2 V for a catalyst loading of 6.0 mg cm-2. No significant performance degradation was observed for 480 h continuous operation. The characterization studies indicated that the metal-nitrogen chelate complexes decompose at the temperatures above 800 oC. During the pyrolysis, the transition metals facilitate the incorporation of pyridinic and graphitic nitrogen groups into the carbon matrix, and the carbon surface modified with nitrogen is active for ORR. In order to elucidate the role of transition metal precursor played in the formation of active sites in the non-precious metal catalysts, a novel ruthenium-based chelate (RuNx) catalyst was synthesized by using RuCl3 and propylene diammine as the Ru and N precursors, respectively, followed by high-temperature pyrolysis. This catalyst exhibited comparable catalytic activity and selectivity for ORR as the Pt catalyst. A theoretical analysis is made of the four-electron reduction reaction of oxygen to water over the mixed anion and cation (202) surface of pentlandite structure Co9Se8, one of several selenide phases. Reversible potentials for forming adsorbed reaction intermediates in acid are predicted using adsorption energies calculated with the Vienna ab initio simulation program (VASP) and the known bulk solution values together in a linear Gibbs energy relationship. The effect of hydrophobic and structural properties of a single/dual-layer cathode gas diffusion layer on mass transport in PEM fuel cells was studied using an analytical expression. The simulations indicated that liquid water transport at the cathode is controlled by the fraction of hydrophilic surface and the average pore diameter in the cathode gas diffusion layer. The optimized hydrophobicity and pore geometry in a dual-layer cathode GDL leads to an effective water management, and enhances the oxygen diffusion kinetics.

Branko N. Popov

2009-02-20T23:59:59.000Z

158

Chromium-Assisted Synthesis of Platinum Nanocube Electrocatalysts  

Science Conference Proceedings (OSTI)

This report describes a novel strategy of chromium-assisted shape control in the synthesis of platinum nanocubes with high monodispersity. The use of a certain concentration ratio of platinum vs. chromium precursors (typically 1:1) has been demonstrated to enable an effective adsorption of Cr species on the nanocrystal in selective blocking of the adsorption of capping molecules on the different surfaces for the nanocube formation. The cubic shape was evidenced by both high-resolution TEM and x-ray diffraction characterizations, whereas the composition was analyzed by both bulk and surfacesensitive techniques (DCP-AES, EDS and XPS). The results indicated that practically there was no Cr in the nanocubes or only a trace of Cr on the nanocrystal surfaces, demonstrating a high effectiveness in producing Pt nanocubes. A combination of effective oxidative leaving of the adsorbed Cr species and the weaker adsorption of capping molecules on Pt(111) constitutes the kinetic driving force for a faster growth rate of Pt(111) than Pt(100) faces. The understanding of the synergistic correlation between surface metal adsorption and ligand encapsulation in creating a difference in the kinetic growth on different nanocrystal facets has important implication to the design of advanced catalysts.

Loukrakpam, Rameshwori; Chang, Paul; Luo, Jin; Fang, Bin; Mott, Derrick; Bae, In-Tae; Naslund, H. R.; Engelhard, Mark H.; Zhong, Chuan-Jian

2010-10-04T23:59:59.000Z

159

Alkali or alkaline earth metal promoted catalyst and a process for methanol synthesis using alkali or alkaline earth metals as promoters  

DOE Patents (OSTI)

The present invention relates to a novel route for the synthesis of methanol, and more specifically to the production of methanol by contacting synthesis gas under relatively mild conditions in a slurry phase with a heterogeneous catalyst comprising reduced copper chromite impregnated with an alkali or alkaline earth metal. There is thus no need to add a separate alkali or alkaline earth compound. The present invention allows the synthesis of methanol to occur in the temperature range of approximately 100--160 C and the pressure range of 40--65 atm. The process produces methanol with up to 90% syngas conversion per pass and up to 95% methanol selectivity. The only major by-product is a small amount of easily separated methyl formate. Very small amounts of water, carbon dioxide and dimethyl ether are also produced. The present catalyst combination also is capable of tolerating fluctuations in the H[sub 2]/CO ratio without major deleterious effect on the reaction rate. Furthermore, carbon dioxide and water are also tolerated without substantial catalyst deactivation.

Tierney, J.W.; Wender, I.; Palekar, V.M.

1995-01-31T23:59:59.000Z

160

Alkali or alkaline earth metal promoted catalyst and a process for methanol synthesis using alkali or alkaline earth metals as promoters  

DOE Patents (OSTI)

The present invention relates to a novel route for the synthesis of methanol, and more specifically to the production of methanol by contacting synthesis gas under relatively mild conditions in a slurry phase with a heterogeneous catalyst comprising reduced copper chromite impregnated with an alkali or alkaline earth metal. There is thus no need to add a separate alkali or alkaline earth compound. The present invention allows the synthesis of methanol to occur in the temperature range of approximately 100.degree.-160.degree. C. and the pressure range of 40-65 atm. The process produces methanol with up to 90% syngas conversion per pass and up to 95% methanol selectivity. The only major by-product is a small amount of easily separated methyl formate. Very small amounts of water, carbon dioxide and dimethyl ether are also produced. The present catalyst combination also is capable of tolerating fluctuations in the H.sub.2 /CO ratio without major deleterious effect on the reaction rate. Furthermore, carbon dioxide and water are also tolerated without substantial catalyst deactivation.

Tierney, John W. (Pittsburgh, PA); Wender, Irving (Pittsburgh, PA); Palekar, Vishwesh M. (Pittsburgh, PA)

1995-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Heterogeneous Catalysis on Atomically Dispersed Supported Metals: CO2 Reduction on Multifunctional Pd Catalysts  

Science Conference Proceedings (OSTI)

Temperature programmed reaction and scanning transmission electron microscopy experiments were applied to prove the requirement of two different catalyst functionalities for the reduction of CO2 with hydrogen on Pd/Al2O3 and Pd/MWCNT catalysts. The research described in this paper was supported by the Laboratory Directed Research and Development (LDRD) program of the Pacific Northwest National Laboratory (PNNL) and 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 PNNL. PNNL is operated for the US DOE by Battelle Memorial Institute.

Kwak, Ja Hun; Kovarik, Libor; Szanyi, Janos

2013-11-01T23:59:59.000Z

162

Transition Metal Catalyzed Hydroarylation of Multiple Bonds: Exploration of Second Generation Ruthenium Catalysts and Extension to Copper Systems  

DOE Green Energy (OSTI)

Catalysts provide foundational technology for the development of new materials and can enhance the efficiency of routes to known materials. New catalyst technologies offer the possibility of reducing energy and raw material consumption as well as enabling chemical processes with a lower environmental impact. The rising demand and expense of fossil resources has strained national and global economies and has increased the importance of accessing more efficient catalytic processes for the conversion of hydrocarbons to useful products. The goals of the research are to develop and understand single-site homogeneous catalysts for the conversion of readily available hydrocarbons into useful materials. A detailed understanding of these catalytic reactions could lead to the development of catalysts with improved activity, longevity and selectivity. Such transformations could reduce the environmental impact of hydrocarbon functionalization, conserve energy and valuable fossil resources and provide new technologies for the production of liquid fuels. This project is a collaborative effort that incorporates both experimental and computational studies to understand the details of transition metal catalyzed C-H activation and C-C bond forming reactions with olefins. Accomplishments of the current funding period include: (1) We have completed and published studies of C-H activation and catalytic olefin hydroarylation by TpRu{l_brace}P(pyr){sub 3}{r_brace}(NCMe)R (pyr = N-pyrrolyl) complexes. While these systems efficiently initiate stoichiometric benzene C-H activation, catalytic olefin hydroarylation is hindered by inhibition of olefin coordination, which is a result of the steric bulk of the P(pyr){sub 3} ligand. (2) We have extended our studies of catalytic olefin hydroarylation by TpRu(L)(NCMe)Ph systems to L = P(OCH{sub 2}){sub 3}CEt. Thus, we have now completed detailed mechanistic studies of four systems with L = CO, PMe{sub 3}, P(pyr){sub 3} and P(OCH{sub 2}){sub 3}CEt, which has provided a comprehensive understanding of the impact of steric and electronic parameters of 'L' on the catalytic hydroarylation of olefins. (3) We have completed and published a detailed mechanistic study of stoichiometric aromatic C-H activation by TpRu(L)(NCMe)Ph (L = CO or PMe{sub 3}). These efforts have probed the impact of functionality para to the site of C-H activation for benzene substrates and have allowed us to develop a detailed model of the transition state for the C-H activation process. These results have led us to conclude that the C-H bond cleavage occurs by a {sigma}-bond metathesis process in which the C-H transfer is best viewed as an intramolecular proton transfer. (4) We have completed studies of Ru complexes possessing the N-heterocyclic carbene IMes (IMes = 1,3-bis-(2,4,6-trimethylphenyl)imidazol-2-ylidene). One of these systems is a unique four-coordinate Ru(II) complex that catalyzes the oxidative hydrophenylation of ethylene (in low yields) to produce styrene and ethane (utilizing ethylene as the hydrogen acceptor) as well as the hydrogenation of olefins, aldehydes and ketones. These results provide a map for the preparation of catalysts that are selective for oxidative olefin hydroarylation. (5) The ability of TpRu(PMe{sub 3})(NCMe)R systems to activate sp{sup 3} C-H bonds has been demonstrated including extension to subsequent C-C bond forming steps. These results open the door to the development of catalysts for the functionalization of more inert C-H bonds. (6) We have discovered that Pt(II) complexes supported by simple nitrogen-based ligands serve as catalysts for the hydroarylation of olefins. Given the extensive studies of Pt-based catalytic C-H activation, we believe these results will provide an entry point into an array of possible catalysts for hydrocarbon functionalization.

T. Brent Gunnoe

2011-02-17T23:59:59.000Z

163

Low platinum loading electrospun electrodes for proton exchange membrane fuel cells  

E-Print Network (OSTI)

An experimental study was performed to evaluate the utility of electrospun carbon nanofiber supports for sputtered platinum catalyst in proton exchange membrane fuel cells. The performance of the sputtered nanofiber supports ...

Singer, Simcha Lev

2006-01-01T23:59:59.000Z

164

A Novel Nanobio Catalyst for Biofuels | Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

Multiple Crystal Cavities for Unlimited X-ray Energy Resolution and Multiple Crystal Cavities for Unlimited X-ray Energy Resolution and Coherence An Intriguing Twist in the Structure of a Cobalt Oxide Catalyst Breaking Records in Neurological Microradiology Exposing Valence-Bond Model Inadequacies Plants' Rapid Response System Revealed Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed A Novel Nanobio Catalyst for Biofuels AUGUST 27, 2012 Bookmark and Share Core shell nanoparticle inside Apo. Nanoparticles synthesized from noble metals such as ruthenium, rhodium, palladium, silver (Ag), osmium, iridium, platinum, and gold (Au) are attracting increased attention by researchers around the world looking for

165

Theoretical Study of the Structure, Stability and Oxygen Reduction Activity of Ultrathin Platinum Nanowires  

Science Conference Proceedings (OSTI)

We use density functional theory to study the difference in the structure, stability and catalytic reactivity between ultrathin, 0.5- 1.0 nm diameter, platinum nanotubes and nanowires. Model nanowires were formed by inserting an inner chain of platinum atoms in small diameter nanotubes. In this way more stable, nonhollow structures were formed. The difference in the electronic structure of platinum nanotubes and nanowires was examined by inspecting the density of surface states and band structure. Furthermore, reactivity towards the oxygen reduction reaction of platinum nanowires was addressed by studying the change in the chemisorption energies of oxygen and hydroxyl groups, induced by inserting the inner chain of platinum atoms into the hollow nanotubes. Both ultrathin platinum nanotubes and nanowires show distinct properties compared to bulk platinum. Nanotubes with diameters larger than 1 nm show promise for use as oxygen reduction catalysts.

Matanovic, Ivana; Kent, Paul; Garzon, Fernando; Henson, Neil J.

2012-10-10T23:59:59.000Z

166

Catalysts for the production of hydrocarbons from carbon monoxide and water  

DOE Patents (OSTI)

A method of converting low H/sub 2//CO ratio syngas to carbonaceous products comprising reacting the syngas with water or steam at 200 to 350/sup 0/C in the presence of a metal catalyst supported on zinc oxide. Hydrocarbons are produced with a catalyst selected from cobalt, nickel or ruthenium and alcohols are produced with a catalyst selected from palladium, platinum, ruthenium or copper on the zinc oxide support. The ratio of the reactants are such that for alcohols and saturated hydrocarbons: (2n + 1) greater than or equal to x greater than or equal to O and for olefinic hydrocarbons: 2n greater than or equal to x greater than or equal to O where n is the number of carbon atoms in the product and x is the molar amount of water in the reaction mixture.

Sapienza, R.S.; Slegeir, W.A.; Goldberg, R.I.

1985-11-06T23:59:59.000Z

167

Pt loaded carbon aerogel catalyst for catalytic exchange reactions between water and hydrogen gas  

Science Conference Proceedings (OSTI)

We report development and characterization of platinum doped carbon aerogel catalyst for catalytic exchange reactions between water and hydrogen gas. The carbon aerogel with uniformly dispersed platinum nanoparticles was prepared by adding platinum precursor during the sol-gel process. Thereafter colloidal PTFE was mixed with the platinum doped carbon aerogel powder and coated on Dixon rings to obtain hydrophobic catalyst with required mechanical strength. Detailed studies have been carried out to observe the effect of physical characteristics of the catalyst powder (surface area and pore size of aerogels

P. K. Gupta

2013-01-01T23:59:59.000Z

168

Highly Dispersed Alloy Catalyst for Durability  

DOE Green Energy (OSTI)

Achieving DOE�¢����s stated 5000-hr durability goal for light-duty vehicles by 2015 will require MEAs with characteristics that are beyond the current state of the art. Significant effort was placed on developing advanced durable cathode catalysts to arrive at the best possible electrode for high performance and durability, as well as developing manufacturing processes that yield significant cost benefit. Accordingly, the overall goal of this project was to develop and construct advanced MEAs that will improve performance and durability while reducing the cost of PEMFC stacks. The project, led by UTC Power, focused on developing new catalysts/supports and integrating them with existing materials (membranes and gas diffusion layers (GDLs)) using state-of-the-art fabrication methods capable of meeting the durability requirements essential for automotive applications. Specifically, the project work aimed to lower platinum group metals (PGM) loading while increasing performance and durability. Appropriate catalysts and MEA configuration were down-selected that protects the membrane, and the layers were tailored to optimize the movements of reactants and product water through the cell to maximize performance while maintaining durability.

Vivek S. Murthi (Primary Contact), Elise Izzo, Wu Bi, Sandra Guerrero and Lesia Protsailo

2013-01-08T23:59:59.000Z

169

Experimental Study of In Situ Combustion with Decalin and Metallic Catalyst  

E-Print Network (OSTI)

Using a hydrogen donor and a catalyst for upgrading and increasing oil recovery during in situ combustion is a known and proven technique. Based on research conducted on this process, it is clear that widespread practice in industry is the usage of tetralin as a hydrogen donor. The objective of the study is to find a cheaper hydrogen donor with better or the same upgrading performance. Decalin (C10H18) is used in this research as a hydrogen donor. The experiments have been carried out using field oil and water saturations, field porosity and crushed core for porous medium. Four in situ combustion runs were performed with Gulf of Mexico heavy oil, and three of them were successful. The first run was a control run without any additives to create a base for comparison. The next two runs were made with premixed decalin (5 percent by oil weight) and organometallic catalyst (750 ppm). The following conditions were kept constant during all experimental runs: air injection rate at 3.1 L/min and combustion tube outlet pressure at 300 psig. Analysis of the performance of decalin as a hydrogen donor in in-situ combustion included comparison of results with an experiment where tetralin was used. Data from experiments of Palmer (Palmer-Ikuku, 2009) was used for this purpose, where the same oil, catalyst and conditions were used. Results of experiments using decalin showed better quality of produced oil, higher recovery factor, faster combustion front movement and higher temperatures of oxidation. API gravity of oil in a run with decalin is higher by 4 points compared to a base run and increased 5 points compared to original oil. Oil production increased by 7 percent of OOIP in comparison with base run and was 2 percent higher than the experiment with tetralin. The time required for the combustion front to reach bottom flange decreased 1.6 times compared to the base run. The experiments showed that decalin and organometallic catalysts perform successfully in in situ combustion, and decalin is a worthy replacement for tetralin.

Mateshov, Dauren

2010-12-01T23:59:59.000Z

170

Chemistry of Cobalt-Platinum Nanocatalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Chemistry of Cobalt-Platinum Nanocatalysts Print Chemistry of Cobalt-Platinum Nanocatalysts Print Bimetallic cobalt-platinum (CoPt) nanoparticles are drawing attention in many areas of catalysis as scientists attempt to reduce precious metal content while maintaining optimum catalytic selectivity and reactivity. Cobalt, an important transition metal used for catalytic hydrogenation reactions of CO and CO2 to produce gaseous or liquid hydrocarbons, has a long history of use in the industrial process of producing synthetic fuels. Researchers explored the role of Pt in Co reducing and oxidizing, and found that the catalytic properties of monometallic and bimetallic nanoparticles of Co are closely related to the oxidation state of Co, which informs the prediction of cobalt oxidation states as reaction conditions are altered. This research also suggests the presence of a tetrahedral cobalt oxide that differs from the Co3O4 spinel structure.

171

Aqueous-phase hydrogenation of acetic acid over transition metal catalysts  

SciTech Connect

Catalytic hydrogenation of acetic acid to ethanol has been carried out in aqueous phase on several metals, with ruthenium being the most active and selective. DFT calculations suggest that the initial CO bond scission yielding acetyl is the key step and that the intrinsic reactivity of the metals accounts for the observed activity.

Olcay, Hakan [University of Massachusetts, Amherst; Xu, Lijun [ORNL; Xu, Ye [ORNL; Huber, George [University of Massachusetts, Amherst

2010-01-01T23:59:59.000Z

172

Surface Oxidation and Dissolution of Metal Nanocatalysts in Acid Medium  

E-Print Network (OSTI)

One of the most important challenges in low-temperature fuel cell technology is improving the catalytic efficiency at the electrode-catalyst where the oxygen reduction reaction (ORR) occurs. Platinum is the best pure catalyst for this reaction but its high cost and scarcity hinder the commercial implementation of fuel cells in automobiles. Pt-based alloys are promising alternatives to substitute platinum while maintaining the efficiency and life-time of the pure catalyst. However, the acid medium and the oxidation of the surface reduce the activity and durability of the alloy catalyst through changes in its local composition and structure. Molecular simulation techniques are applied to characterize the thermodynamics and dynamic evolution of the surface of platinum-based alloy catalysts under reaction conditions.1-10 A simulation scheme of the surface oxidation is proposed which combines classical molecular dynamics (MD) and density functional theory (DFT). This approach is able to reproduce the main features of the oxidation phenomena observed experimentally, it is concluded that the dissolution mechanism of metal atoms involves: 1) Surface segregation of alloy atoms, 2) oxygen absorption into the subsurface of the catalyst, and 3) metal detachment through the interaction with ions in the solvent. Therefore, to improve the durability of platinum-based alloy catalysts, the steps of the dissolution mechanism must be prevented. A versatile 3-D kinetic Monte Carlo (KMC) code is developed to study the degradation and dealloying in nanocatalysts. The results on the degradation of Pt nanoparticles under different potential regimes demonstrate that the dissolution depends on the potential path to which the nanocatalyst is exposed. Metal atoms detach from the boundaries of (111) facets expecting a reduction in the activity of the nanoparticle. Also, the formation of Pt hollow nanoparticles by the Kirkendall effect is addressed, the role of vacancies is crucial in the removal of the non-noble core that yields to hollow nanoparticles. To investigate the reasons for the experimentally found enhanced ORR activity in porous/hollow nanoparticles, the effect of subsurface vacancies on the main ORR activity descriptors is studied with DFT. It is found that an optimum amount of vacancies may enhance the ORR activity of Pt-monolayer catalysts over certain alloy cores by changing the binding energies of O and OH.

Callejas-Tovar, Juan

2012-08-01T23:59:59.000Z

173

Catalyst system comprising a first catalyst system tethered to a supported catalyst  

DOE Patents (OSTI)

The present invention provides new catalyst formats which comprise a supported catalyst tethered to a second and different catalyst by a suitable tethering ligand. A preferred system comprises a heterogeneous supported metal catalyst tethered to a homogeneous catalyst. This combination of homogeneous and heterogeneous catalysts has a sufficient lifetime and unusually high catalytic activity in arene hydrogenations, and potentially many other reactions as well, including, but not limited to hydroformylation, hydrosilation, olefin oxidation, isomerization, hydrocyanation, olefin metathesis, olefin polymerization, carbonylation, enantioselective catalysis and photoduplication. These catalysts are easily separated from the products, and can be reused repeatedly, making these systems very economical.

Angelici, Robert J. (Ames, IA); Gao, Hanrong (Ames, IA)

1998-08-04T23:59:59.000Z

174

In situ formation of coal gasification catalysts from low cost alkali metal salts  

DOE Patents (OSTI)

A carbonaceous material, such as crushed coal, is admixed or impregnated with an inexpensive alkali metal compound, such as sodium chloride, and then pretreated with a stream containing steam at a temperature of 350.degree. to 650.degree. C. to enhance the catalytic activity of the mixture in a subsequent gasification of the mixture. The treatment may result in the transformation of the alkali metal compound into another, more catalytically active, form.

Wood, Bernard J. (Santa Clara, CA); Brittain, Robert D. (Cupertino, CA); Sancier, Kenneth M. (Menlo Park, CA)

1985-01-01T23:59:59.000Z

175

One-Pot Formation of Functionalized Indole and Benzofuran Derivatives Using a Single Bifunctional Ruthenium Catalyst  

E-Print Network (OSTI)

Bifunctional Ruthenium Catalyst Reji N. Nair • Paul J. Lee •bifunctional ruthenium catalyst for cyclization of terminalof transi- tion metal based catalysts have been reported to

Nair, Reji N.; Lee, Paul J.; Grotjahn, Douglas B.

2010-01-01T23:59:59.000Z

176

THE MECHANISM AND KINETICS OF FISCHER-TROPSCH SYNTHESIS OVER SUPPORTED RUTHENIUM CATALYSTS  

E-Print Network (OSTI)

Structure of Metallic Catalysts", Academic Press Inc. , Newselectivity of these catalysts. Several appendices dealingOver Supported Ruthenium Catalysts ABSTRACT The effects of

Kellner, Carl Stephen

2013-01-01T23:59:59.000Z

177

(Selective carbon oxygen bond scission during reactions of oxygenates on single crystal catalysts)  

SciTech Connect

We have discovered that the carbon-oxygen bond in methanol can be selectively broken if the surface structure of the platinum catalyst is appropriately tailored. The objective of this project is to determine if variations in surface structure allow one to selectively break C-O and C-H bonds. The decomposition of a wide range of oxygenates on several carefully chosen faces of group VIII metals will be examined to see when C-O bond scission occurs and what new chemistry we can find on stepped surfaces.

1992-01-01T23:59:59.000Z

178

[Selective carbon oxygen bond scission during reactions of oxygenates on single crystal catalysts]. Progress report  

SciTech Connect

We have discovered that the carbon-oxygen bond in methanol can be selectively broken if the surface structure of the platinum catalyst is appropriately tailored. The objective of this project is to determine if variations in surface structure allow one to selectively break C-O and C-H bonds. The decomposition of a wide range of oxygenates on several carefully chosen faces of group VIII metals will be examined to see when C-O bond scission occurs and what new chemistry we can find on stepped surfaces.

1992-08-01T23:59:59.000Z

179

Oxygen Reduction Reaction on Dispersed and Core-Shell Metal Alloy Catalysts: Density Functional Theory Studies  

E-Print Network (OSTI)

Pt-based alloy surfaces are used to catalyze the electrochemical oxygen reduction reaction (ORR), where molecular oxygen is converted into water on fuel cell electrodes. In this work, we address challenges due to the cost of high Pt loadings in the cathode electrocatalyst, as well as those arising from catalyst durability. We aim to develop an increased understanding of the factors that determine ORR activity together with stability against surface segregation and dissolution of Pt-based alloys. We firstly focus on the problem of determining surface atomic distribution resulting from surface segregation phenomena. We use first-principles density functional theory (DFT) calculations on PtCo and Pt3Co overall compositions, as well as adsorption of water and atomic oxygen on PtCo(111) and Pt-skin structures. The bonding between water and surfaces of PtCo and Pt-skin monolayers are investigated in terms of orbital population. Also, on both surfaces, the surface reconstruction effect due to high oxygen coverage and water co-adsorption is investigated. Although the PtCo structures show good activity, a large dissolution of Co atoms tends to occur in acid medium. To tackle this problem, we examine core-shell structures which showed improved stability and activity compared to Pt(111), in particular, one consisting of a surface Pt-skin monolayer over an IrCo or Ir3Co core, with or without a Pd interlayer between the Pt surface and the Ir-Co core. DFT analysis of surface segregation, surface stability against dissolution, surface Pourbaix diagrams, and reaction mechanisms provide useful predictions on catalyst durability, onset potential for water oxidation, surface atomic distribution, coverage of oxygenated species, and activity. The roles of the Pd interlayer in the core-shell structures that influence higher ORR activity are clarified. Furthermore, the stability and activity enhancement of new shell-anchor-core structures of Pt/Fe-C/core, Pt/Co-C/core and Pt/Ni-C/core are demonstrated with core materials of Ir, Pd3Co, Ir3Co, IrCo and IrNi. Based on the analysis, Pt/Fe-C/Ir, Pt/Co-C/Ir, Pt/Ni-C/Ir, Pt/Co-C/Pd3Co, Pt/Fe-C/Pd3Co, Pt/Co- C/Ir3Co, Pt/Fe-C/Ir3Co, Pt/Co-C/IrCo, Pt/Co-C/IrNi, and Pt/Fe-C/IrNi structures show promise in terms of both improved durability and relatively high ORR activity.

Hirunsit, Pussana

2010-08-01T23:59:59.000Z

180

Transition Metal Sulfide Electrocatalysts for PEM Fuel Cells  

NLE Websites -- All DOE Office Websites (Extended Search)

Transition Metal Sulfide Transition Metal Sulfide Electrocatalysts for PEM Fuel Cells Hua Zhang 1 , Ysmael Verde-Gómez 1 and Allan J. Jacobson 1 Alejandra Ramirez 2 and Russell R. Chianelli 2 1 Department of Chemistry, University of Houston Houston, TX 77204 2 Materials Research and Technology Institute, University of Texas at El Paso, El Paso, TX 79968 Transition Metal Sulfide Electrocatalysts for PEM Fuel Cells Hua Zhang 1 , Ysmael Verde-Gómez 1 and Allan J. Jacobson 1 Alejandra Ramirez 2 and Russell R. Chianelli 2 1 Department of Chemistry, University of Houston Houston, TX 77204 2 Materials Research and Technology Institute, University of Texas at El Paso, El Paso, TX 79968 March 21, 2003 Objectives ¾ Investigate non-platinum electro-catalysts with CO tolerance ¾ Focus on transition metal sulfides as electro-catalysts

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181

Electrocatalyst for oxygen reduction with reduced platinum oxidation and dissolution rates  

DOE Patents (OSTI)

The invention relates to platinum-metal oxide composite particles and their use as electrocatalysts in oxygen-reducing cathodes and fuel cells. The invention particularly relates to methods for preventing the oxidation of the platinum electrocatalyst in the cathodes of fuel cells by use of these platinum-metal oxide composite particles. The invention additionally relates to methods for producing electrical energy by supplying such a fuel cell with an oxidant, such as oxygen, and a fuel source, such as hydrogen.

Adzic, Radoslav (East Setauket, NY); Zhang, Junliang (Stony Brook, NY); Vukmirovic, Miomir (Port Jefferson Station, NY)

2011-11-22T23:59:59.000Z

182

Electrocatalyst for oxygen reduction with reduced platinum oxidation and dissolution rates  

DOE Patents (OSTI)

The invention relates to platinum-metal oxide composite particles and their use as electrocatalysts in oxygen-reducing cathodes and fuel cells. The invention particularly relates to methods for preventing the oxidation of the platinum electrocatalyst in the cathodes of fuel cells by use of these platinum-metal oxide composite particles. The invention additionally relates to methods for producing electrical energy by supplying such a fuel cell with an oxidant, such as oxygen, and a fuel source, such as hydrogen.

Adzic, Radoslav; Zhang, Junliang; Vukmirovic, Miomir

2012-11-13T23:59:59.000Z

183

Method of depositing a catalyst on a fuel cell electrode  

DOE Patents (OSTI)

Fuel cell electrodes comprising a minimal load of catalyst having maximum catalytic activity and a method of forming such fuel cell electrodes. The method comprises vaporizing a catalyst, preferably platinum, in a vacuum to form a catalyst vapor. A catalytically effective amount of the catalyst vapor is deposited onto a carbon catalyst support on the fuel cell electrode. The electrode preferably is carbon cloth. The method reduces the amount of catalyst needed for a high performance fuel cell electrode to about 0.3 mg/cm.sup.2 or less.

Dearnaley, Geoffrey (San Antonio, TX); Arps, James H. (San Antonio, TX)

2000-01-01T23:59:59.000Z

184

REFORMULATION OF COAL-DERIVED TRANSPORTATION FUELS: SELECTIVE OXIDATION OF CARBON MONOXIDE ON METAL FOAM CATALYSTS  

DOE Green Energy (OSTI)

Hydrocarbon fuels must be reformed in a series of steps to provide hydrogen for use in proton exchange membrane fuel cells (PEMFCs). Preferential oxidation (PROX) is one method to reduce the CO concentration to less than 10 ppm in the presence of {approx}40% H{sub 2}, CO{sub 2}, and steam. This will prevent CO poisoning of the PEMFC anode. Structured supports, such as ceramic monoliths, can be used for the PROX reaction. Alternatively, metal foams offer a number of advantages over the traditional ceramic monolith.

Paul Chin; Xiaolei Sun; George W. Roberts; Amornmart Sirijarhuphan; Sourabh Pansare; James G. Goodwin Jr; Richard W. Rice; James J. Spivey

2005-06-01T23:59:59.000Z

185

Au/MxOy/TiO2 catalysts for CO oxidation: promotional effect of main-group, transition, and rare-earth metal oxide additives.  

SciTech Connect

Au/TiO2 catalysts are active for CO oxidation, but they suffer from high-temperature sintering of the gold particles, and few attempts have been made to promote or stabilize Au/TiO2. Our recent communication addressed these issues by loading gold onto Al2O3/TiO2 prepared via surface-sol-gel processing of Al(sec-OC4H9)3 on TiO2. In our current full paper, Au/Al2O3/TiO2 catalysts were prepared alternatively by thermal decomposition of Al(NO3)3 on TiO2 followed by loading gold, and the influences of the decomposition temperature and Al2O3 content were systematically surveyed. This facile method was subsequently extended to the preparation of a battery of metal oxide-modified Au/TiO2 catalysts virtually not reported. It was found that Au/TiO2 modified by CaO, NiO, ZnO, Ga2O3, Y2O3, ZrO2, La2O3, Pr2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Dy2O3, Ho2O3, Er2O3, or Yb2O3 could retain significant activity at ambient temperature even after aging in O2-He at 500 C, whereas unmodified Au/TiO2 lost its activity. Moreover, some 200 C-calcined promoted catalysts showed high activity even at about -100 C. The deactivation and regeneration of some of these new catalysts were studied. This work furnished novel catalysts for further fundamental and applied research.

Ma, Zhen [ORNL; Overbury, Steven {Steve} H [ORNL; Dai, Sheng [ORNL

2007-01-01T23:59:59.000Z

186

Membrane catalyst layer for fuel cells  

DOE Patents (OSTI)

A gas reaction fuel cell incorporates a thin catalyst layer between a solid polymer electrolyte (SPE) membrane and a porous electrode backing. The catalyst layer is preferably less than about 10 {mu}m in thickness with a carbon supported platinum catalyst loading less than about 0.35 mgPt/cm{sup 2}. The film is formed as an ink that is spread and cured on a film release blank. The cured film is then transferred to the SPE membrane and hot pressed into the surface to form a catalyst layer having a controlled thickness and catalyst distribution. The layer has adequate gas permeability so that cell performance is not affected and has a density and particle distribution effective to optimize proton access to the catalyst and electronic continuity for electron flow from the half-cell reaction occurring at the catalyst.

Wilson, M.S.

1991-02-19T23:59:59.000Z

187

Adsorption and decomposition of Ru{sub 3}(CO){sub 9}(CH{sub 3}CN){sub 3} at platinum surfaces: An X-ray photoelectron spectroscopy and Fourier transform-infrared spectroscopy study  

Science Conference Proceedings (OSTI)

The direct methanol fuel cell (DMFC) is an attractive power source for mobile applications due to the high-energy density of methanol, the portability and ease of distribution of liquid rather than gaseous fuel, and elimination of the need for a bulky, power-consuming fuel reformer. There are several factors limiting the power output of polymer electrolyte DMFCs. One of the major factors is the slow kinetics of the methanol electrooxidation reaction on the conventional platinum catalyst material. A CH{sub 3}CN-modified triruthenium carbonyl cluster, Ru{sub 3}(CO){sub 9}(CH{sub 3}CN){sub 3}(I), has been adsorbed on platinum and platinum oxide surfaces from dichloromethane solutions. The modified surface has been characterized by X-ray photoelectron spectroscopy (XPS) and polarized grazing angle Fourier transform-infrared (FT-IR) microscopy. The proposed mechanism for the adsorption of I involves the chemisorption of the metal cluster at the platinum surface by losing the acetonitrile ligand. The original cluster, Ru{sub 3}(CO){sub 12}, could not be adsorbed under the same experimental conditions used for cluster I. The cluster-modified surface was treated with hydrogen for the reduction of the cluster to its metallic state on the Pt surface. This was done at different temperatures. The XPS results show the formation of a complex Ru-RuO{sub 2}-RuO{sub 3}/Pt surface.

Fachini, E.R.; Cabrera, C.R. [Univ. of Puerto Rico, San Juan (Puerto Rico). Dept. of Chemistry

1999-02-02T23:59:59.000Z

188

Nucleation of Ultrathin, Continuous, Conformal Metal Films Using Atomic Layer Deposition and Applications as Fuel Cell Catalysts  

A research team at the University of Colorado at Boulder led by Steven George has developed a method to prepare a conformal thin film of platinum or one of its alloys onto a substrate, and more particularly to reduce the cost associated with ...

189

The Science and Engineering of Durable Ultralow PGM Catalysts- 2012 DOE-EERE-FCT annual progress report  

Science Conference Proceedings (OSTI)

Minimizing the quantity of Pt group metals used in polymer membrane fuel cells (PEMFCs) is one of the remaining grand challenges for fuel cell commercialization. Tremendous progress has been achieved over the last two decades in decreasing the Pt loading required for efficient fuel cell performance. Unfortunately, the fluctuations in the price of Pt represent a substantial barrier to the economics of widespread fuel cell use. Durability and impurity tolerance are also challenges that are tightly coupled to fuel cell Pt electrode loading. Traditional approaches to decreasing the amount of Pt required for good performance include: (1) Increasing mass activity by decreasing Pt particle size by supporting on carbon; (2) Alloy formulation Pt-Co, Pt-Cr alloys to improve mass activity; (3) Increasing Pt utilization by optimization of electronic and ionic contact of the Pt particles; (4) Improving conductivity of the electronic and ionic conducting constituents of the membrane electrode assembly; and (5) Improving reactant to and product mass transport away from the electroactive sites. Recent novel approaches include the nanoengineering of core shell catalysts and Pt particles of unusual geometries such as nanowires/whiskers. The success of the aforementioned approaches has been great; however further advances using such approaches have been hampered by a lack of underlining scientific understanding of the catalyst activity, particle growth mechanisms, and optimization strategies for designing composite electrodes The objectives of this report are: (1) Development of durable, high mass activity Platinum Group Metal (PGM) cathode catalysts-enabling lower cost fuel cells; (2) Elucidation of the fundamental relationships between PGM catalyst shape, particle size and activity to help design better catalysts; (3) Optimization of the cathode electrode layer to maximize the performance of PGM catalysts-improving fuel cell performance and lowering cost; (4) Understanding the performance degradation mechanisms of high mass activity cathode catalysts-provide insights to better catalyst design; and (5) Development and testing of fuel cells using ultra-low loading high activity PGM catalysts-validation of advanced concepts.

Garzon, Fernando H. [Los Alamos National Laboratory

2012-07-16T23:59:59.000Z

190

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

DOE Green Energy (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

191

Chalcogen catalysts for polymer electrolyte fuel cell  

DOE Patents (OSTI)

A methanol-tolerant cathode catalyst and a membrane electrode assembly for fuel cells that includes such a cathode catalyst. The cathode catalyst includes a support having at least one transition metal in elemental form and a chalcogen disposed on the support. Methods of making the cathode catalyst and membrane electrode assembly are also described.

Zelenay, Piotr (Los Alamos, NM); Choi, Jong-Ho (Los Alamos, NM); Alonso-Vante, Nicolas (France, FR); Wieckowski, Andrzej (Champaign, IL); Cao, Dianxue (Urbana, IL)

2010-08-24T23:59:59.000Z

192

Oxidation catalyst  

DOE Patents (OSTI)

The present invention generally relates to catalyst systems and methods for oxidation of carbon monoxide. The invention involves catalyst compositions which may be advantageously altered by, for example, modification of the catalyst surface to enhance catalyst performance. Catalyst systems of the present invention may be capable of performing the oxidation of carbon monoxide at relatively lower temperatures (e.g., 200 K and below) and at relatively higher reaction rates than known catalysts. Additionally, catalyst systems disclosed herein may be substantially lower in cost than current commercial catalysts. Such catalyst systems may be useful in, for example, catalytic converters, fuel cells, sensors, and the like.

Ceyer, Sylvia T. (Cambridge, MA); Lahr, David L. (Cambridge, MA)

2010-11-09T23:59:59.000Z

193

Catalytic reforming process using noble metal alkaline zeolites  

Science Conference Proceedings (OSTI)

This patent describes improvement in a process wherein a gasoline boiling range hydrocarbonaceous feedstock is catalytically reformed in the presence of hydrogen in a reforming process unit comprised of serially connected reactors wherein each of the reactors contains a supported noble metal-containing catalyst. The improvement comprises the noble-metal catalyst of at least one reactor being selected from the group consisting of alkaline faujasite zeolite, L zeolite and zeolites isostructural thereto, which catalysts are prepared by a: contacting an alkaline faujasite zeolite, L zeolite, or zeolite isostructural thereto, with a noble metal composition selected from Pt(acetylacetonate){sub 2} or Pd(acetylacetonate){sub 2} for an effective amount of time to form a substantially homogeneous mixture and to incorporate the platinum and/or palladium into the near surface regions of the zeolite, but not to disperse the platinum and/or palladium throughout the entire zeolite; and calcining the so treated zeolite at a temperature from about 250 {degrees} C to about 600 {degrees} C for an effective amount of time.

Schweizer, A.E.

1991-02-12T23:59:59.000Z

194

Catalysts for carbon and coal gasification  

DOE Patents (OSTI)

Catalyst for the production of methane from carbon and/or coal by means of catalytic gasification. The catalyst compostion containing at least two alkali metal salts. A particulate carbonaceous substrate or carrier is used.

McKee, Douglas W. (Burnt Hills, NY); Spiro, Clifford L. (Scotia, NY); Kosky, Philip G. (Schenectady, NY)

1985-01-01T23:59:59.000Z

195

Crystalline titanate catalyst supports  

DOE Patents (OSTI)

A series of new crystalline titanates (CT) are shown to have considerable potential as catalyst supports. For Pd supported catalyst, the catalytic activity for pyrene hydrogenation was substantially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide supports.

Anthony, Rayford G. (Bryan, TX); Dosch, Robert G. (Albuquerque, NM)

1993-01-01T23:59:59.000Z

196

Crystalline titanate catalyst supports  

DOE Patents (OSTI)

A series of new crystalline titanates (CT) are shown to have considerable potential as catalyst supports. For Pd supported catalyst, the catalytic activity for pyrene hydrogenation was substantially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide supports.

Anthony, R.G.; Dosch, R.G.

1991-12-31T23:59:59.000Z

197

Crystalline titanate catalyst supports  

DOE Patents (OSTI)

A series of new crystalline titanates (CT) are shown to have considerable potential as catalyst supports. For Pd supported catalyst, the catalytic activity for pyrene hydrogenation was substantially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide supports.

Anthony, R.G.; Dosch, R.G.

1993-01-05T23:59:59.000Z

198

MANGANESE OXIDE AS A NEW CATHODE CATALYST IN MICROBIAL FUEL CELLS (MFCs).  

E-Print Network (OSTI)

??This study focused on manganese oxides with a cryptomelane-type octahedral molecular sieve (OMS-2) structure to replace platinum as a cathode catalyst in microbial fuel cells… (more)

Li, Xiang

2011-01-01T23:59:59.000Z

199

Selectivity, activity, and metal-support interactions of Rh bimetallic catalysts. Progress report, 15 November 1981-15 August 1982  

DOE Green Energy (OSTI)

We report on a detailed investigation of the effect of TiO/sub 2/ support on Rh-Ag interaction as exhibited in catalytic activity. The temporal evolution of activity over Rh-Ag/TiO/sub 2/ for ethane hydrogenolysis and hydrogen chemisorption as a function of temperature, Ag to Rh ratio, the Rh particle size, Rh loading, and ambient gas were studied. Preliminary extended x-ray absorption fine structure (EXAFS) analysis of Rh/TiO/sub 2/ catalysts indicate that 100% exposed (dispersed) catalyst prepared by ion exchange may be atomically dispersed after low temperature reduction. 7 figures, 1 table.

Haller, G L

1982-08-01T23:59:59.000Z

200

Hydrocarbon synthesis catalyst and method of preparation and use thereof. [DOE patent application  

DOE Patents (OSTI)

A catalyst for the synthesis of hydrocarbons from carbon monoxide and hydrogen composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants. The catalyst is preferably used in dilute slurry form, which is desirable from a heat transfer standpoint.

Sapienza, R.S.; Sansone, M.J.; Slegeir, W.A.R.

1981-08-14T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Adsorption of propane, isopropyl, and hydrogen on cluster models of the M1 phase of Mo-V-Te-Nb-O mixed metal oxide catalyst  

Science Conference Proceedings (OSTI)

The Mo-V-Te-Nb-O mixed metal oxide catalyst possessing the M1 phase structure is uniquely capable of directly converting propane into acrylonitrile. However, the mechanism of this complex eight-electron transformation, which includes a series of oxidative H-abstraction and N-insertion steps, remains poorly understood. We have conducted a density functional theory study of cluster models of the proposed active and selective site for propane ammoxidation, including the adsorption of propane, isopropyl (CH{sub 3}CHCH{sub 3}), and H which are involved in the first step of this transformation, that is, the methylene C-H bond scission in propane, on these active site models. Among the surface oxygen species, the telluryl oxo (Te=O) is found to be the most nucleophilic. Whereas the adsorption of propane is weak regardless of the MO{sub x} species involved, isopropyl and H adsorption exhibits strong preference in the order of Te=O > V=O > bridging oxygens > empty Mo apical site, suggesting the importance of TeO{sub x} species for H abstraction. The adsorption energies of isopropyl and H and consequently the reaction energy of the initial dehydrogenation of propane are strongly dependent on the number of ab planes included in the cluster, which points to the need to employ multilayer cluster models to correctly capture the energetics of surface chemistry on this mixed metal oxide catalyst.

Govindasamy, Agalya [University of Cincinnati; Muthukumar, Kaliappan [University of Cincinnati; Yu, Junjun [University of Cincinnati; Xu, Ye [ORNL; Guliants, Vadim V. [University of Cincinnati

2010-01-01T23:59:59.000Z

202

Support shape effect in metal oxide catalysis: ceria nanoshapes supported vanadia catalysts for oxidative dehydrogenation of iso-butane  

SciTech Connect

The activation energy of VOx/CeO2 catalysts in oxidative dehydrogenation of iso-butane was found dependent on the shape of ceria support: rods < octahedra, closely related to the surface oxygen vacancy formation energy and defects amount of the two ceria supports with different crystallographic surface planes.

Wu, Zili [ORNL; Schwartz, Viviane [ORNL; Li, Meijun [ORNL; Rondinone, Adam Justin [ORNL; Overbury, Steven {Steve} H [ORNL

2012-01-01T23:59:59.000Z

203

Platinum- and Platinum Alloy-Coated Palladium and Palladium ...  

... “Core-Protected Platinum Monolayer Shell High-Stability Electrocatalysts for Fuel-Cell Cathodes,” Angewandte Chemie Intl. Ed. 49, 8602 (2010) ...

204

Chemistry of Cobalt-Platinum Nanocatalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Chemistry of Cobalt-Platinum Nanocatalysts Chemistry of Cobalt-Platinum Nanocatalysts Print Monday, 25 February 2013 15:59 Bimetallic cobalt-platinum (CoPt) nanoparticles are...

205

Catalyst for selective conversion of synthesis gas and method of making the catalyst  

DOE Patents (OSTI)

A Fischer-Tropsch (F-T) catalyst, a method of making the catalyst and an F-T process utilizing the catalyst by which synthesis gas, particularly carbon-monoxide rich synthesis gas is selectively converted to higher hydrocarbons of relatively narrow carbon number range. In general, the selective and notably stable catalyst, consists of an inert carrier first treated with a Group IV B metal compound (such as zirconium or titanium), preferably an alkoxide compound, and subsequently treated with an organic compound of an F-T metal catalyst, such as cobalt, iron or ruthenium carbonyl. Reactions with air and water and calcination are specifically avoided in the catalyst preparation procedure.

Dyer, Paul N. (Allentown, PA); Pierantozzi, Ronald (Macungie, PA)

1986-01-01T23:59:59.000Z

206

Supported fischer-tropsch catalyst and method of making the catalyst  

DOE Patents (OSTI)

A Fischer-Tropsch catalyst and a method of making the catalyst for a Fischer-Tropsch process utilizing the catalyst by which synthesis gas, particularly carbon-monoxide rich synthesis gas, is selectively converted to higher hydrocarbons of relatively narrow carbon number range is disclosed. In general, the selective and notably stable catalyst, consist of an inert carrier first treated with a Group IV B metal compound (such as zirconium or titanium), preferably an alkoxide compound, and subsequently treated with an organic compound of a Fischer-Tropsch metal catalyst, such as cobalt, iron or ruthenium carbonyl. Reactions with air and water and calcination are specifically avoided in the catalyst preparation procedure.

Dyer, Paul N. (Allentown, PA); Pierantozzi, Ronald (Orefield, PA); Withers, Howard P. (Douglassville, PA)

1987-01-01T23:59:59.000Z

207

Catalysts and method  

DOE Patents (OSTI)

An improved catlayst and method for the oxyhydrochlorination of methane is disclosed. The catalyst includes a pyrogenic porous support on which is layered as active material, cobalt chloride in major proportion, and minor proportions of an alkali metal chloride and of a rare earth chloride. On contact of the catalyst with a gas flow of methane, HC1 and oxygen, more than 60% of the methane is converted and of that converted more than 40% occurs as monochloromethane. Advantageously, the monochloromethane can be used to produce gasoline boiling range hydrocarbons with the recycle of HCl for further reaction. This catalyst is also of value for the production of formic acid as are analogous catalysts with lead, silver or nickel chlorides substituted for the cobalt chloride.

Taylor, Charles E. (Pittsburgh, PA); Noceti, Richard P. (Pittsburgh, PA)

1991-01-01T23:59:59.000Z

208

Transition-metal chromophore as a new, sensitive spectroscopic tag for proteins. Selective covalent labeling of histidine residues in cytochromes c with chloro(2,2':6',2''-terpyridine)platinum(II) chloride  

SciTech Connect

Reactivity and selectivity of Pt(trpy)Cl/sup +/ toward proteins are studied with cytochromes c from horse and tuna as examples. The new transition-metal reagent is specific for histidine residues at pH 5. The reaction, facile one-step displacement of the Cl/sup -/ ligand by imidazole, produces good yield. The binding sites, His 26 and His 33 in the horse protein and His 26 in the tuna protein, are identified by UV-vis spectrophotometry and by peptide-mapping experiments. Model complexes with imidazole, histidine, histidine derivatives, and histidine-containing peptides are prepared and characterized. The covalently attached Pt(trpy)/sup 2 +/ labels allow easy separation of the protein derivatives by cation-exchange chromatography. The labels do not perturb the conformation and reduction potential of cytochrome c, as shown by UV-vis spectrophotometry, cyclic voltammetry, differential-pulse voltammetry, EPR spectroscopy, and /sup 1/H NMR spectroscopy. The selectivity of Pt(trpy)Cl/sup +/ is entirely opposite from that of PtCl/sub 4//sup 2 -/ although both of them are platinum(II)-chloro complexes. Owing to an interplay between the steric and electronic effects of the terpyridyl ligand, the new reagent is unreactive toward methionine (a thio ether) and cystine (a disulfide), which are otherwise highly nucleophilic ligands, but very reactive toward imidazole, which is otherwise a relatively weak ligand. Unusual and useful selectivity of preformed transition-metal complexes toward proteins evidently can be achieved by a judicious choice of ancillary ligands.

Ratilla, E.M.A.; Brothers, H.M. II; Kostic, N.M.

1987-07-22T23:59:59.000Z

209

Chemistry of Cobalt-Platinum Nanocatalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Chemistry of Cobalt-Platinum Nanocatalysts Print Bimetallic cobalt-platinum (CoPt) nanoparticles are drawing attention in many areas of catalysis as scientists attempt to reduce...

210

Porous Metals for Jewelry - Lawrence Livermore National Laboratory  

Jewelry is typically made of alloys of precious metals (gold, platinum, silver, etc). These metals are typically dense and can weigh a significant amount.

211

Investigations on the use of main group metal complexes of salen ligands as catalysts for the copolymerization of CO2 and epoxides  

E-Print Network (OSTI)

Current industrial processes for the production of polycarbonates, a thermoplastic valued for commercial applications, leave much to be desired from an environmental viewpoint. Research into alternative methods for production of polycarbonates has focused on the copolymerization of carbon dioxide and epoxides for the benefits of eliminating phosgene as a reagent, and for the economic impact of incorporating CO2 as a low cost C1 feedstock. Early work in this field focused on the use of zinc-derived catalysts, but recent studies indicate that chromium complexes of the salen (N,N-bis-(salicylidene)-1,2-ethylene diimine) family of ligands are far superior to the zinc complexes in terms of reactivity and diminishing the formation of unwanted byproducts. Concomitant to the studies of chromium salen complexes, investigations of main-group salen metal complexes were carried out. Aluminum complexes were able to produce polycarbonate in the presence of tetrabutyl ammonium salts and neutral Lewis bases. Gallium complexes were essentially inactive for generating any product. Tin(IV) complexes were active for the production of polyether, the result of homopolymerization of epoxide without CO2 insertion. Tin(II) complexes generated the monomeric cyclic carbonate product but no copolymer. An additional aspect of research relative to this field of study is the development of polymeric materials from several different epoxide monomers. The complex [hydrotris(3-phenyl-pyrazol-1-yl)borate]Cd(II) acetate was used to study the thermodynamics of the binding of a series of potential epoxide monomers to a metal center via 113Cd NMR. Activation of the epoxide by a metal center was found to not play a significant role in the ability of the complex to be subsequently ring-opened for polymerization. A final relevant area of study involved the synthesis of cadmium analogues of Fe/Zn double metal cyanide (DMC) complexes. Heterogeneous DMCs are well known in patent literature as excellent catalysts for the production of polycarbonates and cyclic carbonates from CO2 and epoxides. Previous studies on homogeneous Fe/Zn DMCs have only provided cyclic carbonate. Cd analogues of these species provide a convenient NMR handle for studies on the activity of the metal centers in presence of an epoxide and by changes to the DMC structure.

Billodeaux, Damon Ray

2005-05-01T23:59:59.000Z

212

Transition metal complexes of oxazolinylboranes and cyclopentadienyl-bis(oxazolinyl)borates: Catalysts for asymmetric olefin hydroamination and acceptorless alcohol decarbonylation  

Science Conference Proceedings (OSTI)

The research presented and discussed in this dissertation involves the synthesis of transition metal complexes of oxazolinylboranes and cyclopentadienyl-bis(oxazolinyl)borates, and their application in catalytic enantioselective olefin hydroamination and acceptorless alcohol decarbonylation. Neutral oxazolinylboranes are excellent synthetic intermediates for preparing new borate ligands and also developing organometallic complexes. Achiral and optically active bis(oxazolinyl)phenylboranes are synthesized by reaction of 2-lithio-2-oxazolide and 0.50 equiv of dichlorophenylborane. These bis(oxazolinyl)phenylboranes are oligomeric species in solid state resulting from the coordination of an oxazoline to the boron center of another borane monomer. The treatment of chiral bis(oxazolinyl)phenylboranes with sodium cyclopentadienide provide optically active cyclopentadienyl-bis(oxazolinyl)borates H[PhB(C{sub 5}H{sub 5})(Ox{sup R}){sub 2}] [Ox{sup R} = Ox{sup 4S-iPr,Me2}, Ox{sup 4R-iPr,Me2}, Ox{sup 4S-tBu]}. These optically active proligands react with an equivalent of M(NMe{sub 2}){sub 4} (M = Ti, Zr, Hf) to afford corresponding cyclopentadienyl-bis(oxazolinyl)borato group 4 complexes {PhB(C{sub 5}H{sub 4})(Ox{sup R}){sub 2}}M(NMe{sub 2}){sub 2} in high yields. These group 4 compounds catalyze cyclization of aminoalkenes at room temperature or below, providing pyrrolidine, piperidine, and azepane with enantiomeric excesses up to 99%. Our mechanistic investigations suggest a non-insertive mechanism involving concerted C?N/C?H bond formation in the turnover limiting step of the catalytic cycle. Among cyclopentadienyl-bis(oxazolinyl)borato group 4 catalysts, the zirconium complex {PhB(C{sub 5}H{sub 4})(Ox{sup 4S-iPr,Me2}){sub 2}}Zr(NMe{sub 2}){sub 2} ({S-2}Zr(NMe{sub 2}){sub 2}) displays highest activity and enantioselectivity. Interestingly, {S-2}Zr(NMe{sub 2}){sub 2} also desymmetrizes olefin moieties of achiral non-conjugated aminodienes and aminodiynes during cyclization. The cyclization of aminodienes catalyzed by {S-2}Zr(NMe{sub 2}){sub 2} affords diastereomeric mixture of cis and trans cylic amines with high diasteromeric ratios and excellent enantiomeric excesses. Similarly, the desymmetrization of alkyne moieties in {S-2}Zr(NMe{sub 2}){sub 2}-catalyzed cyclization of aminodiynes provides corresponding cyclic imines bearing quaternary stereocenters with enantiomeric excesses up to 93%. These stereoselective desymmetrization reactions are significantly affected by concentration of the substrate, temperature, and the presence of a noncyclizable primary amine. In addition, both the diastereomeric ratios and enantiomeric excesses of the products are markedly enhanced by N-deuteration of the substrates. Notably, the cationic zirconium-monoamide complex [{S-2}Zr(NMe{sub 2})][B(C{sub 6}F{sub 5}){sub 4}] obtained from neutral {S-2}Zr(NMe{sub 2}){sub 2} cyclizes primary aminopentenes providing pyrrolidines with S-configuration; whereas {S-2}Zr(NMe{sub 2}){sub 2} provides R-configured pyrrolidines. The yttrium complex {S-2}YCH{sub 2}SiMe{sub 3} also affords S-configured pyrrolidines by cyclization of aminopentenes, however the enantiomeric excesses of products are low. An alternative optically active yttrium complex {PhB(C{sub 5}H{sub 4})(Ox{sup 4S-tBu}){sub 2}}YCH{sub 2}SiMe{sub 3} ({S-3}YCH{sub 2}SiMe{sub 3}) is synthesized, which displays highly enantioselective in the cyclization of aminoalkenes at room temperature affording S-configured cyclic amines with enantiomeric excesses up to 96%. A noninsertive mechanism involving a six-membered transition state by a concerted C?N bond formation and N?H bond cleavage is proposed for {S-3}YCH{sub 2}SiMe{sub 3} system based on the kinetic, spectroscopic, and stereochemical features. In the end, a series of bis- and tris(oxazolinyl)borato iridium and rhodium complexes are synthesized with bis(oxazolinyl)phenylborane [PhB(Ox{sup Me2}){sub 2}]{sub n}, tris(oxazolinyl)borane [B(Ox{sup Me2}){sub 3}]n, and tris(4,4-dimethyl-2-oxazolinyl)phenylborate [To{sup M}]{sup ?}. All these new an

Manna, Kuntal [Ames Laboratory

2012-12-17T23:59:59.000Z

213

Deactivation Mechanisms of Pt/Pd-based Diesel Oxidation Catalysts  

Science Conference Proceedings (OSTI)

Currently precious metal-based diesel oxidation catalysts (DOC) containing platinum (Pt) and palladium (Pd) are most commonly used for the oxidation of hydrocarbon and NO in diesel exhaust hydrocarbon oxidation. The present work has been carried out to investigate the deactivation mechanisms of the DOC from its real-world vehicle operation by coupling its catalytic activity measurements with surface characterization including x-ray diffraction, transmission electron microscopy, and x-ray photoelectron spectroscopy. A production Pt-Pd DOC was obtained after being aged on a vehicle driven for 135,000 miles in order to study its deactivation behavior. The performance of the vehicle-aged part was correlated with that of the simulated hydrothermal lab aged sample assuming that Pt-Pd sintering plays a major role in irreversible catalyst deactivation. In addition to the hydrothermal sintering, the deterioration of hydrocarbon and NO oxidation performance was caused by surface poisoning. The role of the various aging factors in determining long-term performance in mobile applications will be discussed.

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

2012-04-30T23:59:59.000Z

214

Catalyst and method for aqueous phase reactions  

DOE Patents (OSTI)

The present invention is a catalyst in the form of a plurality of porous particles wherein each particle is a support having nickel metal catalytic phase or reduced nickel deposited thereon in a first dispersed phase and an additional metal deposited onto the support in a second dispersed phase. The additional metal is effective in retarding or reducing agglomeration or sintering of the nickel metal catalytic phase without substantially affecting the catalytic activity, thereby increasing the life time of the catalyst.

Elliott, Douglas C. (Richland, WA); Hart, Todd R. (Kennewick, WA)

1999-01-01T23:59:59.000Z

215

Membrane catalyst layer for fuel cells  

DOE Patents (OSTI)

A gas reaction fuel cell incorporates a thin catalyst layer between a solid polymer electrolyte (SPE) membrane and a porous electrode backing. The catalyst layer is preferably less than about 10 .mu.m in thickness with a carbon supported platinum catalyst loading less than about 0.35 mgPt/cm.sup.2. The film is formed as an ink that is spread and cured on a film release blank. The cured film is then transferred to the SPE membrane and hot pressed into the surface to form a catalyst layer having a controlled thickness and catalyst distribution. Alternatively, the catalyst layer is formed by applying a Na.sup.+ form of a perfluorosulfonate ionomer directly to the membrane, drying the film at a high temperature, and then converting the film back to the protonated form of the ionomer. The layer has adequate gas permeability so that cell performance is not affected and has a density and particle distribution effective to optimize proton access to the catalyst and electronic continuity for electron flow from the half-cell reaction occurring at the catalyst.

Wilson, Mahlon S. (Los Alamos, NM)

1993-01-01T23:59:59.000Z

216

Laser Catalyst  

INL’s Laser Catalyst is a method for removing contaminant matter from a porous material. A polymer material is applied to a contaminated surface and ...

217

THE COORDINATION CHEMISTRY OF METAL SURFACES  

E-Print Network (OSTI)

48 and the cluster chemistry by the The nickel and platinumL. Muetterties Department of Chemistry, Lawrence Berkeleyphenomenon in metal surface chemistry. Ultra high vacuw:n

Muetterties, Earl L.

2013-01-01T23:59:59.000Z

218

COAL LIQUEFACTION USING ZINC CHLORIDE CATALYST IN AN EXTRACTING SOLVENT MEDIUM  

E-Print Network (OSTI)

Rate Data o a o u a a Catalyst Loading • . Reaction Time . •and Pressure Effect of CO-catalysts and Additives .Co-catalysts • • a. Zinc Metal • b. Nickel and Nickel

Gandhi, Shamim Ahmed

2013-01-01T23:59:59.000Z

219

Investigation of the Effect of In-Situ Catalyst on the Steam Hydrogasification of Biomass  

E-Print Network (OSTI)

Promotion of iron-group catalysts by a calcium salt inet al. , Effects of metal catalysts on CO 2 gasificationbiomass tars with iron oxide catalysts, Fuel, 2008, 87, 451-

FAN, XIN

2012-01-01T23:59:59.000Z

220

An exploration of automotive platinum demand and its impacts on the platinum market  

E-Print Network (OSTI)

The platinum market is a material market of increasing interest, as platinum demand has grown faster than supply in recent years. As a result, the price of platinum has increased, causing end-user firms to experience ...

Whitfield, Christopher George

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

In situ Characterization of Pt Catalysts Supported on Ceria Modified TiO(2) for the WGS reaction: Influence of Ceria Loading  

Science Conference Proceedings (OSTI)

This work analyzes the influence of cerium content (6-15 wt%) on a TiO{sub 2} support over the structure and water gas shift (WGS) activity of Pt catalysts. The structural properties of these Pt/Ce-TiO{sub 2} catalysts were characterized by XRD, TEM and XANES. Physicochemical characterization of the catalysts showed differences in the structure and dispersion of Ce entities on the support with Ce loading. For the samples with low ceria content (6 wt%), cerium is deposited on the support in the form of CeO{sub x} clusters in a highly dispersed state in close interaction with the Ti atoms. The formation of CeO{sub x} clusters at low Ce-loading on the support facilitates the dispersion of small particles of Pt and improves the reducibility of ceria component at low temperatures. The changes in platinum dispersion and support reducibility with Ce-loading on the TiO{sub 2} support lead to significant differences in the WGS activity. Pt supported on the sample with lower Ce content (6 wt%) shows better activity than those corresponding to catalysts with higher Ce content (15 wt%). Activity measurements coupled with catalysts characterization suggest that the improvement in the reducibility of the support with lower Ce content was associated with the presence of CeO{sub x} clusters of high reducibility that improve the chemical activity of the oxide-metal interfaces at which the WGS reaction takes place.

Rodriguez J. A.; Barrio, L.; Zhou, G.; Gonzalez, I.D.; Estrella, M.; Hanson, J.; Navarro, R.M.; Fierro, J.L.G.

2012-01-01T23:59:59.000Z

222

Catalyst and process development for hydrogen preparation from future fuel cell feedstocks. Quarterly progress report, January 1, 1980-March 31, 1980. [Pt/Rh, Pd, Pt, Rh, Ni/Rh, Rh/Re, Ni  

DOE Green Energy (OSTI)

Catalysts are being screened to steam reform hydrocarbons in an autothermal reformer (STR). Twenty-one samples have been screened in a 1-in.-diam (ATR) reactor using No. 2 oil as the hydrocarbon feed. A series of platinum-rhodium catalysts were evaluated to study the effect of varying compositions. A sample containing 1.7% Pt/0.3% Rh was most active but the difference among the samples was within the range of test variability. Development of a more realistic test has been started. The effect of O/sub 2//C level on the gas composition leaving the catalytic partial oxidation section has been determined. The amount of unreacted oil increases as O/sub 2//C level decreases. The unreacted oil is more aromatic than the feedstock. The gas composition contains considerably more olefins as the O/sub 2//C level decreases. Post-run catalyst characterization indicates that the catalyst carrier does not deteriorate in the ATR test. A drastic decrease in CO chemisorption is noted on the Pt/Rh samples. This decline in CO chemisorption could either be due to metal sintering or to carbon deposition on the metal. Other analysis are required to determine which is causing the decline in CO chemisorption. Very low coke levels were found on Pt, Rh, and Pt/Rh samples. Addition of Rh to nickel reduces the coke level over that observed for nickel catalysts.

Yarrington, R M; Feins, I R; Hwang, H S

1980-04-01T23:59:59.000Z

223

Partial oxidation catalyst  

DOE Patents (OSTI)

A two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion. The dehydrogenation portion is a group VIII metal and the oxide-ion conducting portion is selected from a ceramic oxide crystallizing in the fluorite or perovskite structure. There is also disclosed a method of forming a hydrogen rich gas from a source of hydrocarbon fuel in which the hydrocarbon fuel contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion at a temperature not less than about 400.degree. C. for a time sufficient to generate the hydrogen rich gas while maintaining CO content less than about 5 volume percent. There is also disclosed a method of forming partially oxidized hydrocarbons from ethanes in which ethane gas contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion for a time and at a temperature sufficient to form an oxide.

Krumpelt, Michael (Naperville, IL); Ahmed, Shabbir (Bolingbrook, IL); Kumar, Romesh (Naperville, IL); Doshi, Rajiv (Downers Grove, IL)

2000-01-01T23:59:59.000Z

224

Catalysts for Oxidation of Mercury in Flue Gas  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalysts for Oxidation of Mercury in Flue Gas Catalysts for Oxidation of Mercury in Flue Gas Opportunity The Department of Energy's National Energy Technology Laboratory (NETL) is seeking licensing partners interested in implementing United States Patent Number 7,776,780 entitled "Catalysts for Oxidation of Mercury in Flue Gas." Disclosed in this patent are catalysts for the oxidation of elemental mercury in flue gas. These novel catalysts include iridium (Ir), platinum/iridium (Pt/Ir), and Thief carbons. The catalyst materials will adsorb the oxidizing agents HCl, Cl 2 , and other halogen species in the flue gas stream that are produced when fuel is combusted. These adsorbed oxidizing agents can then react with elemental mercury in the stream, which is difficult to capture, and oxidize it to form Hg (II) species,

225

Process for coal liquefaction using electrodeposited catalyst  

DOE Patents (OSTI)

A process for the liquefaction of solid hydrocarbonaceous materials is disclosed. Particles of such materials are electroplated with a metal catalyst and are then suspended in a hydrocarbon oil and subjected to hydrogenolysis to liquefy the solid hydrocarbonaceous material. A liquid product oil is separated from residue solid material containing char and the catalyst metal. The catalyst is recovered from the solid material by electrolysis for reuse. A portion of the product oil can be employed as the hydrocarbon oil for suspending additional particles of catalyst coated solid carbonaceous material for hydrogenolysis.

Moore, Raymond H. (Richland, WA)

1978-01-01T23:59:59.000Z

226

Integrated current collector and catalyst support  

DOE Patents (OSTI)

An integrated current collecting electrode for a molten carbonate fuel cell includes a corrugated metal conductive strip positioned in contact with a catalyst layer. The corrugations of the metal strip form a plurality of gas channels immediately adjacent the surface of the catalyst through which a reactant gas flows. Each channel is filled with a particulate material to maintain separation between the metal strip and the catalyst in ensuring gas channel integrity. The catalyst may be in the form of a compacted, particulate material provided the particle size of the material within the gas channels is larger than that of the catalyst particles to prevent catalyst migration to the metal conductor and provide reactant gas access to the catalyst layer. The gas channels formed by the corrugations of the metal strip are arranged in an offset pattern along the direction of gas flow for improved reactant gas distribution to the catalyst layer. The particulate material positioned within the gas flow channels may be a ceramic conductor such as a perovskite or a spinel for enhanced current collection.

Bregoli, Lawrence J. (Southwick, MA)

1985-10-22T23:59:59.000Z

227

Carbon Monoxide Tolerant Electrocatalyst with Low Platinum ...  

Carbon Monoxide Tolerant Electrocatalyst with Low Platinum Loading and a Process for its Preparation Brookhaven National Laboratory. Contact BNL About ...

228

Bioinspired Molecular Co-Catalysts Bonded to a Silicon Photocathode for Solar Hydrogen Evolution  

DOE Green Energy (OSTI)

The production of fuels from sunlight represents one of the main challenges in the development of a sustainable energy system. Hydrogen is the simplest fuel to produce and although platinum and other noble metals are efficient catalysts for photoelectrochemical hydrogen evolution earth-abundant alternatives are needed for large-scale use. We show that bioinspired molecular clusters based on molybdenum and sulphur evolve hydrogen at rates comparable to that of platinum. The incomplete cubane-like clusters (Mo{sub 3}S{sub 4}) efficiently catalyse the evolution of hydrogen when coupled to a p-type Si semiconductor that harvests red photons in the solar spectrum. The current densities at the reversible potential match the requirement of a photoelectrochemical hydrogen production system with a solar-to-hydrogen efficiency in excess of 10% (ref. 16). The experimental observations are supported by density functional theory calculations of the Mo{sub 3}S{sub 4} clusters adsorbed on the hydrogen-terminated Si(100) surface, providing insights into the nature of the active site.

Hou, Yidong

2011-11-08T23:59:59.000Z

229

Cr-free Fe-based metal oxide catalysts for high temperature water gas shift reaction of fuel processor using LPG  

Science Conference Proceedings (OSTI)

The goal of this study was to identify the most suitable chromium-free iron-based catalysts for the HTS (high temperature shift) reaction of a fuel processor using LPG. Hexavalent chromium (Cr6+) in the commercial HTS catalyst has been regarded as hazardous material. We selected Ni and Co as the substitution for chromium in the Fe-based HTS catalyst and investigated the HTS activities of these Crfree catalysts at LPG reformate condition. Cr-free Fe-based catalysts which contain Ni, Zn, or Co instead of Cr were prepared by coprecipitation method and the performance of the catalysts in HTS was evaluated under gas mixture conditions (42% H2, 10% CO, 37% H2O, 8% CO2, and 3% CH4; R (reduction factor): about 1.2) similar to the gases from steam reforming of LPG (100% conversion at steam/carbon ratio = 3), which is higher than R (under 1) of typically studied LNG reformate condition. Among the prepared Cr-free Febased catalysts, the 5 wt%-Co/Fe/20 wt%-Ni and 5 wt%-Zn/Fe/20 wt%-Ni catalysts showed good catalytic activity under this reaction condition simulating LPG reformate gas.

lee, Joon Y.; Lee, Dae-Won; Lee, Kwan Young; Wang, Yong

2009-08-15T23:59:59.000Z

230

Formation of alcohol conversion catalysts  

DOE Patents (OSTI)

The method of the present invention involves a composition containing an intimate mixture of (a) metal oxide support particles and (b) a catalytically active metal oxide from Groups VA, VIA, or VIIA, its method of manufacture, and its method of use for converting alcohols to aldehydes. During the conversion process, catalytically active metal oxide from the discrete catalytic metal oxide particles migrates to the oxide support particles and forms a monolayer of catalytically active metal oxide on the oxide support particle to form a catalyst composition having a higher specific activity than the admixed particle composition.

Wachs, Israel E. (Bridgewater, NJ); Cai, Yeping (Louisville, KY)

2001-01-01T23:59:59.000Z

231

TEMPERATURE-PROGRAMMED DESORPTION AND REACTION OF CO AND H2 ON ALUMINA-SUPPORTED RUTHENIUM CATALYST  

E-Print Network (OSTI)

over Group VIII Metal Catalysts" J.T. Kummer and P.H.and Fischer- Iron Catalyst", to be published. P.R. Wentrek,on Alumina-supported Ruthenium Catalyst" to be published. M.

Low, Gordon Gongngai

2011-01-01T23:59:59.000Z

232

Sub-10 nm Platinum Nanocrystals with Size and Shape Control: Catalytic Study for Ethylene and Pyrrole Hydrogenation  

SciTech Connect

Platinum nanocubes and nanopolyhedra with tunable size from 5 to 9 nm were synthesized by controlling the reducing rate of metal precursor ions in a one-pot polyol synthesis. A two-stage process is proposed for the simultaneous control of size and shape. In the first stage, the oxidation state of the metal ion precursors determined the nucleation rate and consequently the number of nuclei. The reaction temperature controlled the shape in the second stage by regulation of the growth kinetics. These well-defined nanocrystals were loaded into MCF-17 mesoporous silica for examination of catalytic properties. Pt loadings and dispersions of the supported catalysts were determined by elemental analysis (ICP-MS) and H2 chemisorption isotherms, respectively. Ethylene hydrogenation rates over the Pt nanocrystals were independent of both size and shape and comparable to Pt single crystals. For pyrrole hydrogenation, the nanocubes enhanced ring-opening ability and thus showed a higher selectivity to n-butylamine as compared to nanopolyhedra.

Tsung, Chia-Kuang; Kuhn, John N.; Huang, Wenyu; Aliaga, Cesar; Hung, Ling-I; Somorjai, Gabor A.; Yang, Peidong

2009-03-02T23:59:59.000Z

233

Improved catalysts for carbon and coal gasification  

DOE Patents (OSTI)

This invention relates to improved catalysts for carbon and coal gasification and improved processes for catalytic coal gasification for the production of methane. The catalyst is composed of at least two alkali metal salts and a particulate carbonaceous substrate or carrier is used. 10 figures, 2 tables.

McKee, D.W.; Spiro, C.L.; Kosky, P.G.

1984-05-25T23:59:59.000Z

234

Biomass-derived Hydrogen-evolution catalyst and electrode  

combination of biomass and earth-abundant metals has resulted in a durable catalyst for splitting water into oxygen and hydrogen, which can be used as ...

235

CATALYST EVALUATION FOR A SULFUR DIOXIDE-DEPOLARIZED ELECTROLYZER  

DOE Green Energy (OSTI)

Thermochemical processes are being developed to provide global-scale quantities of hydrogen. A variant on sulfur-based thermochemical cycles is the Hybrid Sulfur (HyS) Process which uses a sulfur dioxide depolarized electrolyzer (SDE) to produce the hydrogen. Testing examined the activity and stability of platinum and palladium as the electrocatalyst for the SDE in sulfuric acid solutions. Cyclic and linear sweep voltammetry revealed that platinum provided better catalytic activity with much lower potentials and higher currents than palladium. Testing also showed that the catalyst activity is strongly influenced by the concentration of the sulfuric acid electrolyte.

Hobbs, D; Hector Colon-Mercado, H

2007-01-31T23:59:59.000Z

236

Brookhaven National Laboratory Technology Marketing Summaries ...  

Wind Energy; Partners (27) Visual ... platinum-metal oxide composites can ... This ternary catalyst consisting of platinum and rhodium on carbon-supported tin dioxide ...

237

Processes and catalysts for conducting Fischer-Tropsch synthesis in a slurry bubble column reactor  

DOE Patents (OSTI)

Processes and catalysts are disclosed for conducting Fischer-Tropsch synthesis in a slurry bubble column reactor (SBCR). One aspect of the invention involves the use of cobalt catalysts without noble metal promotion in an SBCR. Another aspect involves using palladium promoted cobalt catalysts in an SBCR. Methods for preparing noble metal promoted catalysts via totally aqueous impregnation and procedures for producing attrition resistant catalysts are also provided. 1 fig.

Singleton, A.H.; Oukaci, R.; Goodwin, J.G.

1999-08-17T23:59:59.000Z

238

Processes and catalysts for conducting fischer-tropsch synthesis in a slurry bubble column reactor  

DOE Patents (OSTI)

Processes and catalysts for conducting Fischer-Tropsch synthesis in a slurry bubble column reactor (SBCR). One aspect of the invention involves the use of cobalt catalysts without noble metal promotion in an SBCR. Another aspect involves using palladium promoted cobalt catalysts in an SBCR. Methods for preparing noble metal promoted catalysts via totally aqueous impregnation and procedures for producing attrition resistant catalysts are also provided.

Singleton, Alan H. (Marshall Township, Allegheny County, PA); Oukaci, Rachid (Allison Park, PA); Goodwin, James G. (Cranberry Township, PA)

1999-01-01T23:59:59.000Z

239

Catalyst for hydrotreating carbonaceous liquids  

DOE Patents (OSTI)

A catalyst for denitrogenating and desulfurating carbonaceous liquid such as solvent refined coal includes catalytic metal oxides impregnated within a porous base of mostly alumina with relatively large pore diameters, surface area and pore volume. The base material includes pore volumes of 0.7-0.85 ml/g, surface areas of 200-350 m.sup.2 /g and pore diameters of 85-200 Angstroms. The catalytic metals impregnated into these base materials include the oxides of Group VI metals, molybdenum and tungsten, and the oxides of Group VIII metals, nickel and cobalt, in various combinations. These catalysts and bases in combination have effectively promoted the removal of chemically combined sulfur and nitrogen within a continuous flowing mixture of carbonaceous liquid and hydrogen gas.

Berg, Lloyd (Bozeman, MT); McCandless, Frank P. (Bozeman, MT); Ramer, Ronald J. (Idaho Falls, ID)

1982-01-01T23:59:59.000Z

240

Catalysts for coal liquefaction processes  

SciTech Connect

Improved catalysts for catalytic solvent refining or hydroliquefaction of non-anthracitic coal at elevated temperatures under hydrogen pressure in a hydrogen donor solvent comprise a combination of zinc or copper, or a compound thereof, and a Group VI or non-ferrous Group VIII metal, or a compound thereof.

Garg, Diwakar (Macungie, PA)

1986-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Perovskite catalysts for oxidative coupling  

DOE Patents (OSTI)

Perovskites of the structure A[sub 2]B[sub 2]C[sub 3]O[sub 10] are useful as catalysts for the oxidative coupling of lower alkane to heavier hydrocarbons. A is alkali metal; B is lanthanide or lanthanum, cerium, neodymium, samarium, praseodymium, gadolinium or dysprosium; and C is titanium.

Campbell, K.D.

1991-06-25T23:59:59.000Z

242

Catalysts for coal liquefaction processes  

DOE Patents (OSTI)

Improved catalysts for catalytic solvent refining or hydroliquefaction of non-anthracitic coal at elevated temperatures under hydrogen pressure in a hydrogen donor solvent comprise a combination of zinc or copper, or a compound thereof, and a Group VI or non-ferrous Group VIII metal, or a compound thereof.

Garg, D.

1986-10-14T23:59:59.000Z

243

Thief Carbon Catalyst for Oxidation of Mercury in Effluent Stream  

NLE Websites -- All DOE Office Websites (Extended Search)

Carbon Catalyst for Oxidation of Mercury in Effluent Carbon Catalyst for Oxidation of Mercury in Effluent Stream Contact NETL Technology Transfer Group techtransfer@netl.doe.gov January 2012 Significance * Oxidizes heavy metal contaminants, especially mercury, in gas streams * Uses partially combusted coal ("Thief" carbon) * Yields an inexpensive catalyst * Cheap enough to be a disposable catalyst * Cuts long-term costs * Simultaneously addresses oxidation and adsorption issues Applications * Any process requiring removal of heavy

244

Catalyst structure and method of fischer-tropsch synthesis  

Science Conference Proceedings (OSTI)

The present invention includes Fischer-Tropsch catalysts, reactions using Fischer-Tropsch catalysts, methods of making Fischer-Tropsch catalysts, processes of hydrogenating carbon monoxide, and fuels made using these processes. The invention provides the ability to hydrogenate carbon monoxide with low contact times, good conversion rates and low methane selectivities. In a preferred method, the catalyst is made using a metal foam support.

Wang, Yong [Richland, WA; Vanderwiel, David P [Richland, WA; Tonkovich, Anna Lee Y [Pasco, WA; Gao, Yufei [Kennewick, WA; Baker, Eddie G [Pasco, WA

2002-12-10T23:59:59.000Z

245

Catalyst for converting synthesis gas to liquid motor fuels  

DOE Patents (OSTI)

The addition of an inert metal component, such as gold, silver or copper, to a Fischer-Tropsch catalyst comprising cobalt enables said catalyst to convert synthesis gas to liquid motor fuels at about 240.degree.-370.degree. C. with advantageously reduced selectivity of said cobalt for methane in said conversion. The catalyst composition can advantageously include a support component, such as a molecular sieve, co-catalyst/support component or a combination of such support components.

Coughlin, Peter K. (Yorktown Heights, NY)

1986-01-01T23:59:59.000Z

246

Thief carbon catalyst for oxidation of mercury in effluent stream  

DOE Patents (OSTI)

A catalyst for the oxidation of heavy metal contaminants, especially mercury (Hg), in an effluent stream is presented. The catalyst facilitates removal of mercury through the oxidation of elemental Hg into mercury (II) moieties. The active component of the catalyst is partially combusted coal, or "Thief" carbon, which can be pre-treated with a halogen. An untreated Thief carbon catalyst can be self-promoting in the presence of an effluent gas streams entrained with a halogen.

Granite, Evan J. (Wexford, PA); Pennline, Henry W. (Bethel Park, PA)

2011-12-06T23:59:59.000Z

247

Catalysts for Lean Engine Emission Control - Emissions & Emission Controls  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalysts for Lean Engine Emission Control Catalysts for Lean Engine Emission Control Catalysts for controlling NOx from lean engines are studied in great detail at FEERC. Lean NOx Traps (LNTs) and Selective Catalytic Reduction (SCR) are two catalyst technologies of interest. Catalysts are studied from the nanoscale to full scale. On the nanoscale, catalyst powders are analyzed with chemisorptions techniques to determine the active metal surface area where catalysis occurs. Diffuse Reflectance Infrared Fourier Transform (DRIFT) spectroscopy is used to observe the chemical reactions occurring on the catalyst surface during catalyst operation. Both powder and coated catalyst samples are analyzed on bench flow reactors in controlled simulated exhaust environments to better characterize the chemical

248

Catalyst for coal liquefaction process  

SciTech Connect

An improved catalyst for a coal liquefaction process; e.g., the H-Coal Process, for converting coal into liquid fuels, and where the conversion is carried out in an ebullated-catalyst-bed reactor wherein the coal contacts catalyst particles and is converted, in addition to liquid fuels, to gas and residual oil which includes preasphaltenes and asphaltenes. The improvement comprises a catalyst selected from the group consisting of the oxides of nickel molybdenum, cobalt molybdenum, cobalt tungsten, and nickel tungsten on a carrier of alumina, silica, or a combination of alumina and silica. The catalyst has a total pore volume of about 0.500 to about 0.900 cc/g and the pore volume comprises micropores, intermediate pores and macropores, the surface of the intermediate pores being sufficiently large to convert the preasphaltenes to asphaltenes and lighter molecules. The conversion of the asphaltenes takes place on the surface of micropores. The macropores are for metal deposition and to prevent catalyst agglomeration. The micropores have diameters between about 50 and about 200 angstroms (.ANG.) and comprise from about 50 to about 80% of the pore volume, whereas the intermediate pores have diameters between about 200 and 2000 angstroms (.ANG.) and comprise from about 10 to about 25% of the pore volume, and the macropores have diameters between about 2000 and about 10,000 angstroms (.ANG.) and comprise from about 10 to about 25% of the pore volume. The catalysts are further improved where they contain promoters. Such promoters include the oxides of vanadium, tungsten, copper, iron and barium, tin chloride, tin fluoride and rare earth metals.

Huibers, Derk T. A. (Pennington, NJ); Kang, Chia-Chen C. (Princeton, NJ)

1984-01-01T23:59:59.000Z

249

Extraction of nanosized cobalt sulfide from spent hydrocracking catalyst  

Science Conference Proceedings (OSTI)

The processes used for the extraction of metals (Co, Mo, and Al) from spent hydrotreating catalysts were investigated in this study. A detailed mechanism of the metal extraction process is described. Additionally, a simulation study was performed to ...

Samia A. Kosa, Eman Z. Hegazy

2013-01-01T23:59:59.000Z

250

Model Catalysts: Simulating the Complexities of Heterogeneous Catalysts  

Science Conference Proceedings (OSTI)

Surface-science investigations have contributed significantly to heterogeneous catalysis in the past several decades. Fundamental studies of reactive systems on metal single crystals have aided researchers in understanding the effect of surface structure on catalyst reactivity and selectivity for a number of important reactions. Recently, model systems, consisting of metal clusters deposited on planar oxide surfaces, have facilitated the study of metal particle-size and support effects. These model systems not only are useful for carrying out kinetic investigations, but are also amenable to surface spectroscopic techniques, thus enabling investigations under realistic pressures and at working temperatures. By combining surface-science characterization methods with kinetic measurements under realistic working conditions, researchers are continuing to advance the molecular-level understanding of heterogeneous catalysis and are narrowing he pressure and material gap between model and real-world catalysts.

Gao, Feng; Goodman, D. W.

2012-05-01T23:59:59.000Z

251

Catalysis using hydrous metal oxide ion exchangers  

DOE Patents (OSTI)

In a process which is catalyzed by a catalyst comprising an active metal on a carrier, said metal being active as a catalyst for the process, an improvement is provided wherein the catalyst is a hydrous, alkali metal or alkaline earth metal titanate, zirconate, niobate or tantalate wherein alkali or alkaline earth metal cations have been exchanged with a catalytically effective amount of cations of said metal.

Dosch, R.G.; Stephens, H.P.; Stohl, F.V.

1983-07-21T23:59:59.000Z

252

Catalysis using hydrous metal oxide ion exchanges  

DOE Patents (OSTI)

In a process which is catalyzed by a catalyst comprising an active metal on a carrier, said metal being active as a catalyst for the process, an improvement is provided wherein the catalyst is a hydrous, alkali metal or alkaline earth metal titanate, zirconate, niobate or tantalate wherein alkali or alkaline earth metal cations have been exchanged with a catalytically effective amount of cations of said metal.

Dosch, Robert G. (Albuquerque, NM); Stephens, Howard P. (Albuquerque, NM); Stohl, Frances V. (Albuquerque, NM)

1985-01-01T23:59:59.000Z

253

Method of treating intermetallic alloy hydrogenation/oxidation catalysts for improved impurity poisoning resistance, regeneration and increased activity  

DOE Patents (OSTI)

The present invention is directed to a method of treating intermetallic alloy hydrogenation/oxidation catalysts with successive oxidation catalysts with successive oxidation and hydrogenation steps at increased temperature to make the intermetallic alloy hydrogenation or oxidation catalysts less susceptible to deactivation by gas impurities, such as hydrogen sulfide; to increase the ability of the hydrogenation and oxidation catalysts to regenerate after sulfur poisoning; and to increase the activity of the hydrogenation and oxidation catalysts to a point close to their original activities after gas impurity poisoning and regeneration. The treatment processes of the present invention are particularly useful for nickel-containing intermetallic alloy hydrogenation catalysts and platinum-containing intermetallic alloy hydrogenation catalysts and best results are obtained for the zirconium/nickel intermetallic alloy hydrogenation catalysts. 23 figs.

Wright, R.B.

1990-02-12T23:59:59.000Z

254

Nickel/ruthenium catalyst and method for aqueous phase reactions  

DOE Patents (OSTI)

A method of hydrogenation using a catalyst in the form of a plurality of porous particles wherein each particle is a support having nickel metal catalytic phase or reduced nickel deposited thereon in a first dispersed phase and an additional ruthenium metal deposited onto the support in a second dispersed phase. The additional ruthenium metal is effective in retarding or reducing agglomeration or sintering of the nickel metal catalytic phase thereby increasing the life time of the catalyst during hydrogenation reactions.

Elliott, Douglas C. (Richland, WA); Sealock, John L. (West Richland, WA)

1998-01-01T23:59:59.000Z

255

Electrocatalyst Having Gold Monolayers on Platinum ...  

Platinum is the most efficient electrocatalyst for accelerating chemical reactions in fuel cells for electric vehicles. During stop-and-go driving, ...

256

NIST: Spectrum of Platinum - Photographic Observations  

Science Conference Proceedings (OSTI)

... by GHRS. It has a platinum hollow cathode with neon carrier gas and is sealed with a magnesium fluoride window. The ...

257

Hydroprocessing of solvent-refined coal: catalyst-screening results  

SciTech Connect

This report presents the results of screening four catalysts for hydroprocessing a 50 wt% mixture of SRC-I in a prehydrogenated creosote oil using a continuous flow unit. All catalysts employed were nickel-molybdates with varying properties. Reaction conditions were 2000 psi, 8 SCFH of hydrogen, volume hourly space velocity of 0.6 to 1.0 cc of SRC-I/hr/cc of catalyst, and 48 hours at 750/sup 0/F followed by 72 hours at 780/sup 0/F. The results indicate that the Shell 324 catalyst is best for hydrogenation of the feedstock but only marginally better than CB 81-44 for denitrogenation. The CB 81-44 catalyst may be slightly better than Shell 324 for the conversion of the +850/sup 0/F fraction of the feedstock. Desulfurization was uniformly high for all catalysts. Catalysts with a bimodal pore size distribution (i.e., SMR7-6137(1)) appear to be better for denitrogenation than unimodal catalysts (i.e., SMR7-6137(4)) containing the same metals loading. Unimodal catalysts (i.e., Shell 324) with higher metals loadings are comparable to bimodal catalysts (i.e., CB 81-44) containing less metals. The results indicate that pore size distribution and metals loading are important parameters for high activity. Catalysts with a unimodal pore volume distribution are capable of being restored to their original state, while bimodal ones experience a loss in surface area and pore volume and an increase in pellet density. This is attributed to the more efficient use of the interior surface area of the catalyst, which results in higher accumulation of coke and metals. Since coke can be removed via controlled oxidation, the irreversible loss is due to the higher concentrations of metals in the catalyst.

Stiegel, G.J.; Tischer, R.E.; Polinski, L.M.

1982-03-01T23:59:59.000Z

258

Fuel Cell Technologies Office: Non-Platinum Electrocatalysts Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

Non-Platinum Non-Platinum Electrocatalysts Workshop to someone by E-mail Share Fuel Cell Technologies Office: Non-Platinum Electrocatalysts Workshop on Facebook Tweet about Fuel Cell Technologies Office: Non-Platinum Electrocatalysts Workshop on Twitter Bookmark Fuel Cell Technologies Office: Non-Platinum Electrocatalysts Workshop on Google Bookmark Fuel Cell Technologies Office: Non-Platinum Electrocatalysts Workshop on Delicious Rank Fuel Cell Technologies Office: Non-Platinum Electrocatalysts Workshop on Digg Find More places to share Fuel Cell Technologies Office: Non-Platinum Electrocatalysts Workshop on AddThis.com... Publications Program Publications Technical Publications Educational Publications Newsletter Program Presentations Multimedia Conferences & Meetings Annual Merit Review Proceedings

259

Designing Hawaii's First LEED Platinum Net Zero Community: Kaupuni...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Designing Hawaii's First LEED Platinum Net Zero Community: Kaupuni Village Designing Hawaii's First LEED Platinum Net Zero Community: Kaupuni Village U.S. Department of Energy...

260

HYDROGENATION AND CRACKING OF COAL RELATED FUSED-RING STRUCTURES USING ZnCl2 AND AlCl3 CATALYSTS  

E-Print Network (OSTI)

of Molten Salt Catalysts, Ph.D. Thesis, Department ofUSING ZnC1 2 AND AlC1 3 CATALYSTS Sadie S. Salim (Ph.D.With Metal Halide Catalysts Coal Structure Literature Review

Salim, Sadie S.

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Process for alkane group dehydrogenation with organometallic catalyst  

DOE Patents (OSTI)

An improved process is described for the catalytic dehydrogenation of organic molecules having a ##STR1## group to produce a ##STR2## group. The organic molecules are: ##STR3## wherein: A.sup.1, A.sup.2, A.sup.3, and A.sup.4 are each independently P, As or N: E.sup.2 is independently C or N; E.sup.3 is independently C, Si or Ge; E.sup.4 is independently C, Si, or Ge; and E.sup.5 is independently C, Si or Ge; M.sup.1, M.sup.2, M.sup.3, and M.sup.4 each is a metal atom independently selected from the group consisting of ruthenium, rhodium, palladium, osmium, iridium and platinum; Q.sup.1, Q.sup.2, Q.sup.3, and Q.sup.4 are each independently a direct bond, --CH.sub.2 --, --CH.sub.2 CH.sub.2 --, or CH.dbd.CH--; in structure I, structure II or structure IV, R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each independently selected from alkyl, alkenyl, cycloalkyl, and aryl, or R.sup.1 and R.sup.2 together and R.sup.3 and R.sup.4 together form a ring structure having from 4 to 10 carbon atoms, or in structure III, R.sup.5, R.sup.6, R.sup.7, and R.sup.8 are each independently selected from alkyl, alkenyl, cycloalkyl, and aryl, or R.sup.5 and R.sup.6 together and R.sup.7 and R.sup.8 together form a ring structure having from 4 to 10 carbon atoms, at a temperature of between about 100.degree. and 250.degree. C. for between about 1 hr and 300 days in the absence of N.sub.2. The surprisingly stable catalyst is a complex of an organic ligand comprising H, C, Si, N, P atoms, and a platinum group metal. The dehydrogenation is performed between about 100 to 200.degree. C., and has increased turnover.

Kaska, William C. (Goleta, CA); Jensen, Craig M. (Kailua, HI)

1998-01-01T23:59:59.000Z

262

Attrition resistant fluidizable reforming catalyst  

DOE Patents (OSTI)

A method of preparing a steam reforming catalyst characterized by improved resistance to attrition loss when used for cracking, reforming, water gas shift and gasification reactions on feedstock in a fluidized bed reactor, comprising: fabricating the ceramic support particle, coating a ceramic support by adding an aqueous solution of a precursor salt of a metal selected from the group consisting of Ni, Pt, Pd, Ru, Rh, Cr, Co, Mn, Mg, K, La and Fe and mixtures thereof to the ceramic support and calcining the coated ceramic in air to convert the metal salts to metal oxides.

Parent, Yves O. (Golden, CO); Magrini, Kim (Golden, CO); Landin, Steven M. (Conifer, CO); Ritland, Marcus A. (Palm Beach Shores, FL)

2011-03-29T23:59:59.000Z

263

Solid Catalyst – Alkylation  

This is a method used to reactivate solid/liquid catalysts used in INL’s super critical process to produce alkylates. The method brings the catalyst ...

264

Nanosegregated Surfaces as Catalysts for Fuel Cells (IN-07-054)  

Fuel cells are an important component in the energy industry, but the high cost of producing the platinum catalyst—an essential part of a fuel cell—has historically kept fuel cells from being commercially viable. Scientists at Argonne National ...

265

Optimization of Rhodium-Based Catalysts for Mixed Alcohol Synthesis -- 2010 Progress Report  

SciTech Connect

Pacific Northwest National Laboratory has been conducting research for the U.S. Department of Energy, Energy Efficiency Renewable Energy, Biomass Program to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas. In recent years this research has primarily involved the further development of a silica-supported catalyst containing rhodium and manganese that was selected from earlier catalyst screening tests. A major effort during 2010 was to examine alternative catalyst supports to determine whether other supports, besides the Davisil 645 silica, would improve performance. Optimization of the Davisil 645 silica-supported catalyst also was continued with respect to candidate promoters iridium, platinum, and gallium, and examination of selected catalyst preparation and activation alternatives for the baseline RhMn/SiO2 catalyst.

Gerber, Mark A.; Gray, Michel J.; Albrecht, Karl O.; White, J. F.; Rummel, Becky L.; Stevens, Don J.

2010-10-01T23:59:59.000Z

266

Method for producing iron-based catalysts  

DOE Patents (OSTI)

A method for preparing an acid catalyst having a long shelf-life is provided comprising doping crystalline iron oxides with lattice-compatible metals and heating the now-doped oxide with halogen compounds at elevated temperatures. The invention also provides for a catalyst comprising an iron oxide particle having a predetermined lattice structure, one or more metal dopants for said iron oxide, said dopants having an ionic radius compatible with said lattice structure; and a halogen bound with the iron and the metal dopants on the surface of the particle.

Farcasiu, Malvina (Pittsburgh, PA); Kaufman, Phillip B. (Library, PA); Diehl, J. Rodney (Pittsburgh, PA); Kathrein, Hendrik (McMurray, PA)

1999-01-01T23:59:59.000Z

267

Prealloyed catalyst for growing silicon carbide whiskers  

DOE Patents (OSTI)

A prealloyed metal catalyst is used to grow silicon carbide whiskers, especially in the .beta. form. Pretreating the metal particles to increase the weight percentages of carbon or silicon or both carbon and silicon allows whisker growth to begin immediately upon reaching growth temperature.

Shalek, Peter D. (Los Alamos, NM); Katz, Joel D. (Niagara Falls, NY); Hurley, George F. (Los Alamos, NM)

1988-01-01T23:59:59.000Z

268

Nitrated metalloporphyrins as catalysts for alkane oxidation  

DOE Patents (OSTI)

Compositions of matter comprising nitro-substituted metal complexes of porphyrins are catalysts for the oxidation of alkanes. The metal is iron, chromium, manganese, ruthenium, copper or cobalt. The porphyrin ring has nitro groups attached thereto in meso and/or [beta]-pyrrolic positions.

Ellis, P.E. Jr.; Lyons, J.E.

1994-01-18T23:59:59.000Z

269

Nitrated metalloporphyrins as catalysts for alkane oxidation  

DOE Patents (OSTI)

Compositions of matter comprising nitro-substituted metal complexes of porphyrins are catalysts for the oxidation of alkanes. The metal is iron, chromium, manganese, ruthenium, copper or cobalt. The porphyrin ring has nitro groups attached thereto in meso and/or .beta.-pyrrolic positions.

Ellis, Jr., Paul E. (Downingtown, PA); Lyons, James E. (Wallingford, PA)

1994-01-01T23:59:59.000Z

270

Influence of support material on Ni catalysts for propane dry reforming to synthesis gas.  

E-Print Network (OSTI)

??Ni/SiO2 and Ni/Mg(Al)O catalysts with difference metal loadings have been prepared. The activity, selectivity and stability of supported Ni catalysts for propane dry reforming to… (more)

Dai, Xin

2008-01-01T23:59:59.000Z

271

Process for magnetic beneficiating petroleum cracking catalyst  

DOE Patents (OSTI)

A process for beneficiating a particulate zeolite petroleum cracking catalyst having metal values in excess of 1000 ppm nickel equivalents. The particulate catalyst is passed through a magnetic field in the range of from about 2 Tesla to about 5 Tesla generated by a superconducting quadrupole open-gradient magnetic system for a time sufficient to effect separation of said catalyst into a plurality of zones having different nickel equivalent concentrations. A first zone has nickel equivalents of about 6,000 ppm and greater, a second zone has nickel equivalents in the range of from about 2000 ppm to about 6000 ppm, and a third zone has nickel equivalents of about 2000 ppm and less. The zones of catalyst are separated and the second zone material is recycled to a fluidized bed of zeolite petroleum cracking catalyst. The low nickel equivalent zone is treated while the high nickel equivalent zone is discarded.

Doctor, Richard D. (Lisle, IL)

1993-01-01T23:59:59.000Z

272

Process for magnetic beneficiating petroleum cracking catalyst  

DOE Patents (OSTI)

A process is described for beneficiating a particulate zeolite petroleum cracking catalyst having metal values in excess of 1000 ppm nickel equivalents. The particulate catalyst is passed through a magnetic field in the range of from about 2 Tesla to about 5 Tesla generated by a superconducting quadrupole open-gradient magnetic system for a time sufficient to effect separation of said catalyst into a plurality of zones having different nickel equivalent concentrations. A first zone has nickel equivalents of about 6,000 ppm and greater, a second zone has nickel equivalents in the range of from about 2000 ppm to about 6000 ppm, and a third zone has nickel equivalents of about 2000 ppm and less. The zones of catalyst are separated and the second zone material is recycled to a fluidized bed of zeolite petroleum cracking catalyst. The low nickel equivalent zone is treated while the high nickel equivalent zone is discarded. 1 figures.

Doctor, R.D.

1993-10-05T23:59:59.000Z

273

Iron catalyst for preparation of polymethylene from synthesis gas and method for producing the catalyst  

DOE Patents (OSTI)

This invention relates to a process for synthesizing hydrocarbons; more particularly, the invention relates to a process for synthesizing long-chain hydrocarbons known as polymethylene from carbon monoxide and hydrogen or from carbon monoxide and water or mixtures thereof in the presence of a catalyst comprising iron and platinum or palladium or mixtures thereof which may be supported on a solid material, preferably an inorganic refractory oxide. This process may be used to convert a carbon monoxide containing gas to a product which could substitute for high density polyethylene.

Sapienza, R.S.; Slegeir, W.A.

1990-05-15T23:59:59.000Z

274

Multi-stage catalyst systems and uses thereof  

DOE Patents (OSTI)

Catalyst systems and methods provide benefits in reducing the content of nitrogen oxides in a gaseous stream containing nitric oxide (NO), hydrocarbons, carbon monoxide (CO), and oxygen (O.sub.2). The catalyst system comprises an oxidation catalyst comprising a first metal supported on a first inorganic oxide for catalyzing the oxidation of NO to nitrogen dioxide (NO.sub.2), and a reduction catalyst comprising a second metal supported on a second inorganic oxide for catalyzing the reduction of NO.sub.2 to nitrogen (N.sub.2).

Ozkan, Umit S. (Worthington, OH); Holmgreen, Erik M. (Columbus, OH); Yung, Matthew M. (Columbus, OH)

2009-02-10T23:59:59.000Z

275

Contiguous Platinum Monolayer Oxygen Reduction Electrocatalysts on High-Stability-Low-Cost Supports  

NLE Websites -- All DOE Office Websites (Extended Search)

Contiguous Platinum Monolayer Oxygen Reduction Contiguous Platinum Monolayer Oxygen Reduction Electrocatalysts on High-Stability-Low-Cost Supports Co-PIs: Jia Wang, Miomir Vukmirovic, Kotaro Sasaki, Brookhaven National Laboratory Yang Shao-Horn Massachusetts Institute of Technology Rachel O'Malley, David Thompsett, Sarah Ball, Graham Hard Johnson Matthey Fuel Cells Radoslav Adzic Brookhaven National Laboratory DOE Projects Kickoff Meeting September 30 , 2009 2 Project Overview Project Overview 1. Objectives: Objectives: Developing high performance fuel cell electrocatalysts for the oxygen reduction reaction (ORR) comprising contiguous Pt monolayer Pt monolayer on stable, inexpensive metal or alloy nanorods, nanowires, nanobars and

276

Novel Platinum/Chromium Alloy for the Manufacture of Improved ...  

Novel Platinum/Chromium Alloy for the Manufacture of Improved Coronary Stents National Energy Technology Laboratory

277

Enhanced electrocatalysis of the oxygen reduction reaction based on patterning of platinum surfaces with cyanide  

SciTech Connect

The slow rate of the oxygen reduction reaction in the phosphoric acid fuel cell is the main factor limiting its wide application. Here, we present an approach that can be used for the rational design of cathode catalysts with potential use in phosphoric acid fuel cells, or in any environments containing strongly adsorbing tetrahedral anions. This approach is based on molecular patterning of platinum surfaces with cyanide adsorbates that can efficiently block the sites for adsorption of spectator anions while the oxygen reduction reaction proceeds unhindered. We also demonstrate that, depending on the supporting electrolyte anions and cations, on the same CN-covered Pt(111) surface, the oxygen reduction reaction activities can range from a 25-fold increase to a 50-fold decrease. This behaviour is discussed in the light of the role of covalent and non-covalent interactions in controlling the ensemble of platinum active sites required for high turn over rates of the oxygen reduction reaction.

Strmcnik, D.; Escudero, M.; Kodama, K.; Stamenkovic, V. R.; Cuesta, A.; Markovic, N. M. (Materials Science Division); (Inst. de Quimica Fisica); (Toyota Central R& D Labs.)

2010-10-01T23:59:59.000Z

278

Enhanced electrocatalysis of the oxygen reduction reaction based on pattering of platinum surfaces with cyanide.  

SciTech Connect

The slow rate of the oxygen reduction reaction in the phosphoric acid fuel cell is the main factor limiting its wide application. Here, we present an approach that can be used for the rational design of cathode catalysts with potential use in phosphoric acid fuel cells, or in any environments containing strongly adsorbing tetrahedral anions. This approach is based on molecular patterning of platinum surfaces with cyanide adsorbates that can efficiently block the sites for adsorption of spectator anions while the oxygen reduction reaction proceeds unhindered. We also demonstrate that, depending on the supporting electrolyte anions and cations, on the same CN-covered Pt(111) surface, the oxygen reduction reaction activities can range from a 25-fold increase to a 50-fold decrease. This behaviour is discussed in the light of the role of covalent and non-covalent interactions in controlling the ensemble of platinum active sites required for high turn over rates of the oxygen reduction reaction.

Strmcnik, D.; Escudero-Escribano, M.; Kodama, K.; Stamenkovic, V. R.; Cuesta, A.; Markovic, N. M.; Materials Science Division; Inst. de Quimica Fisica; Toyota Central R& D Labs., Inc.

2010-08-15T23:59:59.000Z

279

Low temperature catalysts for methanol production  

DOE Patents (OSTI)

A catalyst and process useful at low temperatures (below about 160.degree. C.) and preferably in the range 80.degree.-120.degree. C. used in the production of methanol from carbon monoxide and hydrogen is disclosed. The catalyst is used in slurry form and comprises a complex reducing agent derived from the component structure NaH--RONa--M(OAc).sub.2 where M is selected from the group consisting of Ni, Pd, and Co and R is a lower alkyl group containing 1-6 carbon atoms. This catalyst is preferably used alone but is also effective in combination with a metal carbonyl of a group VI (Mo, Cr, W) metal. The preferred catalyst precursor is Nic (where M=Ni and R=tertiary amyl). Mo(CO).sub.6 is the preferred metal carbonyl if such component is used. The catalyst is subjected to a conditioning or activating step under temperature and pressure, similar to the parameters given above, to afford the active catalyst.

Sapienza, Richard S. (1 Miller Ave., Shoreham, NY 11786); Slegeir, William A. (7 Florence Rd., Hampton Bays, NY 11946); O' Hare, Thomas E. (11 Geiger Pl., Huntington Station, NY 11746); Mahajan, Devinder (14 Locust Ct., Selden, NY 11784)

1986-01-01T23:59:59.000Z

280

Low temperature catalysts for methanol production  

DOE Patents (OSTI)

A catalyst and process useful at low temperatures (below about 160/sup 0/C) and preferably in the range 80 to 120/sup 0/C used in the production of methanol from carbon monoxide and hydrogen is disclosed. The catalyst is used in slurry form and comprises a complex reducing agent derived from the component structure NaH-RONa-M(OAc)/sub 2/ where M is selected from the group consisting of Ni, Pd, and Co and R is a lower alkyl group containing 1 to 6 carbon atoms. This catalyst is preferably used alone but is also effective in combination with a metal carbonyl of a group VI (Mo, Cr, W) metal. The preferred catalyst precursor is Nic (where M = Ni and R = tertiary amyl). Mo(CO)/sub 6/ is the preferred metal carbonyl if such component is used. The catalyst is subjected to a conditioning or activating step under temperature and pressure, similar to the parameters given above, to afford the active catalyst.

Sapienza, R.S.; Slegeir, W.A.; O' Hare, T.E.; Mahajan, D.

1985-03-12T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Platinum/Chromium-Based Stents Approved for Treatment of Peripheral Artery  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Platinum/Chromium-Based Stents Approved for Treatment of Peripheral Platinum/Chromium-Based Stents Approved for Treatment of Peripheral Artery Disease Platinum/Chromium-Based Stents Approved for Treatment of Peripheral Artery Disease November 14, 2012 - 12:00pm Addthis Washington, DC - A new stent that incorporates an innovative metal alloy developed by scientists at Boston Scientific Corporation and the U.S. Department of Energy (DOE) has received European approval for use in the treatment of certain peripheral arterial diseases. Initially developed for use as a coronary stent, the new PROMUS ELEMENT™ PLUS BTK drug-eluting stent system is designed for treatment of critical limb ischemia, a severe obstruction of arteries within the extremities which reduces blood flow and can damage tissues. Restoring and maintaining peripheral blood flow in

282

NREL: Biomass Research - Chemical and Catalyst Science Projects  

NLE Websites -- All DOE Office Websites (Extended Search)

Chemical and Catalyst Science Projects Chemical and Catalyst Science Projects A photo of a large white tank the size of a water heater. Several metal fittings stick out of the sides of the tank. Thin tubes are attached to some of the fittings and lead to flow meters and other metal pipes. Researchers use experimental data from this four-inch fluidized bed reactor to develop and validate gasification process models. NREL uses chemical analysis to study biomass-derived products online during the conversion process. Catalysts are used in the thermochemical conversion process to convert tars (a byproduct of gasification) to syngas and to convert syngas to liquid transportation fuels. Among the chemical and catalyst science projects at NREL are: Catalyst Fundamentals NREL is working to develop and understand the performance of catalyst and

283

J13: Surface Reaction of High Corrosion Resistance Metals in ...  

Science Conference Proceedings (OSTI)

Symposium, J. Materials and Processes for Enhanced Performance ... Separation and Recovery Process of Rare Metals from Oil Desulfurization Spent Catalyst.

284

Processing of Tungsten Carbide Reinforced Ceramic and Metal ...  

Science Conference Proceedings (OSTI)

Symposium, J. Materials and Processes for Enhanced Performance ... Separation and Recovery Process of Rare Metals from Oil Desulfurization Spent Catalyst.

285

Radical Ion States of Platinum Acetylide Oligomers  

NLE Websites -- All DOE Office Websites (Extended Search)

R. Miller, and Kirk S. Schanze J. Phys. Chem. B 111, 10871-10880 (2007). Find paper at ACS Publications Abstract: The ion radicals of two series of platinum acetylide oligomers...

286

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

287

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Nanoscale Chemical Imaging of a Working Catalyst Nanoscale Chemical Imaging of a Working Catalyst Print Wednesday, 28 January 2009 00:00 The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

288

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

289

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

290

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

291

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

292

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

293

Investigation of the Effect of In-Situ Catalyst on the Steam Hydrogasification of Biomass  

E-Print Network (OSTI)

metal catalysts on CO 2 gasification reactivity of biomassfeasibility of biomass gasification for power generation,et al. , Biomass gasification in a circulating fluidized

FAN, XIN

2012-01-01T23:59:59.000Z

294

BSA 12-45: Biomass-derived Hydrogen-evolution catalyst and ...  

A simply made, inexpensive combination of biomass and earth-abundant metals has resulted in a durable catalyst for splitting water into oxygen and hydrogen, which can ...

295

BSA 12-45: Biomass-Derived Hydrogen-Evolution Catalyst and ...  

A simply made, inexpensive combination of biomass and earth-abundant metals has resulted in a durable catalyst for splitting water into oxygen and ...

296

Shape-selective catalysts for Fischer-Tropsch chemistry. Final report : January 1, 2001 - December 31, 2008.  

Science Conference Proceedings (OSTI)

Argonne National Laboratory carried 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 was desirable that the catalysts have high selectivity and stability with respect to both mechanical strength and aging properties. It was desired that selectivity be directed toward producing diesel fraction components and avoiding excess yields of both light hydrocarbons and heavy waxes. The original goal was to produce shape-selective catalysts that had the potential to limit the formation of long-chain products and yet retain the active metal sites in a protected 'cage.' This cage would also restrict their loss by attrition during use in slurry-bed reactors. The first stage of this program was to prepare and evaluate iron-containing particulate catalysts. Such catalysts were prepared with silica-containing fractal cages. The activity and strength was essentially the same as that of catalysts without the cages. Since there was no improvement, the program plan was modified as discussed below. 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. An effective FT catalyst consisting of ALD-deposited Co and Pt on a silica support has been prepared and demonstrated. This catalyst was more effective than a similar catalyst deposited upon a support of ALD-deposited Al{sub 2}O{sub 3} on silica. This result implies that the deposition of Al{sub 2}O{sub 3} to form a support is not as effective as desired. The addition of Pt as a Co-containing catalyst promoter has been demonstrated; it appears to primarily affect the catalyst pre-conditioning step. Co on Al{sub 2}O{sub 3} catalyst prepared by the Center for Applied Energy Research (CAER) is more effective than Argonne-prepared ALD-deposited Co on ALD-deposited Al{sub 2}O{sub 3} catalyst. The FT activity of ALD-coated Co catalyst on Al{sub 2}O{sub 3} is about linear with Co level from about 9 to 25%. A cooperative research effort was undertaken to test the deposition of platinum on Co FT catalysts; this Pt influences the effectiveness of catalyst conditioning and its continuing activity. In summary, the ALD Pt at a low concentration (0.1 wt %) was as effective as that of the wet chemical deposition technique of CAER (specifically incipient deposition on a Co catalyst that had been prepared and calcined before the Pt deposition.) The ALD technique appeared to be nominally better than the incipient wetness technique that involved co-deposition of

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

2011-04-11T23:59:59.000Z

297

Shape-selective catalysts for Fischer-Tropsch chemistry. Final report : January 1, 2001 - December 31, 2008.  

DOE Green Energy (OSTI)

Argonne National Laboratory carried 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 was desirable that the catalysts have high selectivity and stability with respect to both mechanical strength and aging properties. It was desired that selectivity be directed toward producing diesel fraction components and avoiding excess yields of both light hydrocarbons and heavy waxes. The original goal was to produce shape-selective catalysts that had the potential to limit the formation of long-chain products and yet retain the active metal sites in a protected 'cage.' This cage would also restrict their loss by attrition during use in slurry-bed reactors. The first stage of this program was to prepare and evaluate iron-containing particulate catalysts. Such catalysts were prepared with silica-containing fractal cages. The activity and strength was essentially the same as that of catalysts without the cages. Since there was no improvement, the program plan was modified as discussed below. 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. An effective FT catalyst consisting of ALD-deposited Co and Pt on a silica support has been prepared and demonstrated. This catalyst was more effective than a similar catalyst deposited upon a support of ALD-deposited Al{sub 2}O{sub 3} on silica. This result implies that the deposition of Al{sub 2}O{sub 3} to form a support is not as effective as desired. The addition of Pt as a Co-containing catalyst promoter has been demonstrated; it appears to primarily affect the catalyst pre-conditioning step. Co on Al{sub 2}O{sub 3} catalyst prepared by the Center for Applied Energy Research (CAER) is more effective than Argonne-prepared ALD-deposited Co on ALD-deposited Al{sub 2}O{sub 3} catalyst. The FT activity of ALD-coated Co catalyst on Al{sub 2}O{sub 3} is about linear with Co level from about 9 to 25%. A cooperative research effort was undertaken to test the deposition of platinum on Co FT catalysts; this Pt influences the effectiveness of catalyst conditioning and its continuing activity. In summary, the ALD Pt at a low concentration (0.1 wt %) was as effective as that of the wet chemical deposition technique of CAER (specifically incipient deposition on a Co catalyst that had been prepared and calcined before the Pt deposition.) The ALD technique appeared to be nominally better than the incipient wetness technique that involved co-deposition of

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

2011-04-11T23:59:59.000Z

298

Tungsten Cathode Catalyst for PEMFC  

DOE Green Energy (OSTI)

Final report for project to evaluate tungsten-based catalyst as a cathode catalyst for PEM cell applications.

Joel B. Christian; Sean P. E. Smith

2006-09-22T23:59:59.000Z

299

Glossary Term - Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Bohr Radius Previous Term (Bohr Radius) Glossary Main Index Next Term (Ceres) Ceres Catalyst A catalyst is a substance that increases the speed of a chemical reaction without being...

300

Vanadium catalysts break down biomass for fuels  

NLE Websites -- All DOE Office Websites (Extended Search)

Vanadium catalysts break down biomass for fuels Vanadium catalysts break down biomass for fuels Vanadium catalysts break down biomass into useful components Breaking down biomass could help in converting biomass to fuels. March 26, 2012 Biomass Due to diminishing petroleum reserves, non-food biomass (lignocellulose) is an attractive alternative as a feedstock for the production of renewable chemicals and fuels. Get Expertise Researcher Susan Hanson Inorganic Isotope & Actinide Chem Email Researcher Ruilian Wu Bioenergy & Environmental Science Email Researcher Louis "Pete" Silks Bioenergy & Environmental Science Email Vanadium is an inexpensive, earth-abundant metal that is well suited for promoting oxidations in air. Vanadium catalysts break down biomass into useful components Due to diminishing petroleum reserves, non-food biomass (lignocellulose) is

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Catalyst Management Planning  

Science Conference Proceedings (OSTI)

Catalyst used in selective catalytic reduction (SCR) systems for NOx control in coal-fired power plants is susceptible to deactivation over time due to exposure to trace elements contained in the coal. In order to sustain the levels of NOx reduction needed to comply with regulatory requirements, periodic replacement of the catalyst modules with new or regenerated catalyst is an essential element in operating an SCR system. Catalyst management planning is a process whereby decisions are made about when ca...

2010-12-21T23:59:59.000Z

302

Method of distributing liquefaction catalysts in solid carbonaceous material  

DOE Patents (OSTI)

A method of dispersing a liquefaction catalyst within coal or other carbonaceous solids involves providing a suspension in oil of microcapsules containing the catalyst. An aqueous solution of a catalytic metal salt is emulsified in the water-immiscible oil and the resulting minute droplets microencapsulated in polymeric shells by interfacial polycondensation. The catalyst is subsequently blended and dispersed throughout the powdered carbonaceous material to be liquefied. At liquefaction temperatures the polymeric microcapsules are destroyed and the catalyst converted to minute crystallites in intimate contact with the carbonaceous material. 2 tables.

Weller, S.W.

1984-05-23T23:59:59.000Z

303

Catalysts and process for hydrogenolysis of sugar alcohols to polyols  

DOE Patents (OSTI)

The present invention provides a process for preparation of low molecular weight polyols from high molecular weight polyols in a hydrogenolysis reaction under elevated temperature and hydrogen pressure. The process comprises providing in a reaction mixture the polyols, a base, and a metal catalyst prepared by depositing a transition metal salt on an inert support, reducing the metal salt to the metal with hydrogen, and passivating the metal with oxygen, and wherein the catalyst is reduced with hydrogen prior to the reaction. In particular, the process provides for the preparation of glycerol, propylene glycol, and ethylene glycol from sugar alcohols such as sorbitol or xylitol. In a preferred process, the metal catalyst comprises ruthenium which is deposited on an alumina, titania, or carbon support, and the dispersion of the ruthenium on the support increases during the hydrogenolysis reaction.

Chopade, Shubham P. (East Lansing, MI); Miller, Dennis J. (Okemos, MI); Jackson, James E. (Haslett, MI); Werpy, Todd A. (West Richland, WA); Frye, Jr., John G. (Richland, WA); Zacher, Alan H. (Richland, WA)

2001-01-01T23:59:59.000Z

304

System for reactivating catalysts  

DOE Patents (OSTI)

A method of reactivating a catalyst, such as a solid catalyst or a liquid catalyst is provided. The method comprises providing a catalyst that is at least partially deactivated by fouling agents. The catalyst is contacted with a fluid reactivating agent that is at or above a critical point of the fluid reactivating agent and is of sufficient density to dissolve impurities. The fluid reactivating agent reacts with at least one fouling agent, releasing the at least one fouling agent from the catalyst. The at least one fouling agent becomes dissolved in the fluid reactivating agent and is subsequently separated or removed from the fluid reactivating agent so that the fluid reactivating agent may be reused. A system for reactivating a catalyst is also disclosed.

Ginosar, Daniel M. (Idaho Falls, ID); Thompson, David N. (Idaho Falls, ID); Anderson, Raymond P. (Idaho Falls, ID)

2010-03-02T23:59:59.000Z

305

Catalyst and process for converting synthesis gas to liquid motor fuels  

DOE Patents (OSTI)

The addition of an inert metal component, such as gold, silver or copper, to a Fischer-Tropsch catalyst comprising cobalt enables said catalyst to convert synthesis gas to liquid motor fuels at about 240.degree.-370.degree. C. with advantageously reduced selectivity of said cobalt for methane in said conversion. The catalyst composition can advantageously include a support component, such as a molecular sieve, co-catalyst/support component or a combination of such support components.

Coughlin, Peter K. (Yorktown Heights, NY)

1987-01-01T23:59:59.000Z

306

Los Alamos catalyst could jumpstart e-cars, green energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalyst could jumpstart e-cars, green energy Catalyst could jumpstart e-cars, green energy Los Alamos catalyst could jumpstart e-cars, green energy The new material has the highest oxygen reduction reaction (ORR) activity in alkaline media of any non-precious metal catalyst developed to date. June 4, 2013 A high-resolution microscopic image of a new type of nanostructured-carbon-based catalyst developed at Los Alamos National Laboratory that could pave the way for reliable, economical next-generation batteries and alkaline fuel cells. (Photo credit: Los Alamos National Laboratory) A high-resolution microscopic image of a new type of nanostructured-carbon-based catalyst developed at Los Alamos National Laboratory that could pave the way for reliable, economical next-generation batteries and alkaline fuel cells. (Photo credit: Los Alamos National

307

Los Alamos catalyst could jumpstart e-cars, green energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalyst could jumpstart e-cars, green energy Catalyst could jumpstart e-cars, green energy Los Alamos catalyst could jumpstart e-cars, green energy The new material has the highest oxygen reduction reaction (ORR) activity in alkaline media of any non-precious metal catalyst developed to date. June 4, 2013 A high-resolution microscopic image of a new type of nanostructured-carbon-based catalyst developed at Los Alamos National Laboratory that could pave the way for reliable, economical next-generation batteries and alkaline fuel cells. (Photo credit: Los Alamos National Laboratory) A high-resolution microscopic image of a new type of nanostructured-carbon-based catalyst developed at Los Alamos National Laboratory that could pave the way for reliable, economical next-generation batteries and alkaline fuel cells. (Photo credit: Los Alamos National

308

New iron catalyst for preparation of polymethylene from synthesis gas  

DOE Patents (OSTI)

This invention relates to a process for synthesizing hydrocarbons; more particularly, the invention relates to a process for synthesizing long-chain hydrocarbons known as polymethylene from carbon monoxide and hydrogen or from carbon monoxide and water or mixtures thereof in the presence of a catalyst comprising iron and platinum or palladium or mixtures thereof which may be supported on a solid material, preferably an inorganic refractory oxide. This process may be used to convert a carbon monoxide containing gas to a product which could substitute for high density polyethylene.

Sapienza, R.S.; Slegeir, W.A.

1988-03-31T23:59:59.000Z

309

Process and catalyst for carbonylating olefins  

DOE Patents (OSTI)

Disclosed is an improved catalyst system and process for preparing aliphatic carbonyl compounds such as aliphatic carboxylic acids, alkyl esters of aliphatic carboxylic acids and anhydrides of aliphatic carboxylic acids by carbonylating olefins in the presence of a catalyst system comprising (1) a first component selected from at least one Group 6 metal, i.e., chromium, molybdenum, and/or tungsten and (2) a second component selected from at least one of certain halides and tertiary and quaternary compounds of a Group 15 element, i.e., nitrogen, phosphorus and/or arsenic, and (3) as a third component, a polar, aprotic solvent. The process employing the improved catalyst system is carried out under carbonylating conditions of pressure and temperature discussed herein. The process constitutes and improvement over known processes since it can be carried out at moderate carbonylation conditions without the necessity of using an expensive noble metal catalyst, volatile, toxic materials such as nickel tetracarbonyl, formic acid or a formate ester. Further, the addition of a polar, aprotic solvent to the catalyst system significantly increases, or accelerates, the rate at which the carbonylation takes place.

Zoeller, Joseph Robert (Kingsport, TN)

1998-06-02T23:59:59.000Z

310

Activity and Evolution of Vapor Deposited Pt-Pd Oxygen Reduction Catalysts for Solid Acid Fuel Cells  

SciTech Connect

The performance of hydrogen fuel cells based on the crystalline solid proton conductor CsH2PO4 is circumscribed by the mass activity of platinum oxygen reduction catalysts in the cathode. Here we report on the first application of an alloy catalyst in a solid acid fuel cell, and demonstrate an activity 4.5 times greater than Pt at 0.8 V. These activity enhancements were obtained with platinum-palladium alloys that were vapor-deposited directly on CsH2PO4 at 210 C. Catalyst mass activity peaks at a composition of 84 at% Pd, though smaller activity enhancements are observed for catalyst compositions exceeding 50 at% Pd. Prior to fuel cell testing, Pd-rich catalysts display lattice parameter expansions of up to 2% due to the presence of interstitial carbon. After fuel cell testing, a Pt-Pd solid solution absent of lattice dilatation and depleted in carbon is recovered. The structural evolution of the catalysts is correlated with catalyst de-activation.

Papandrew, Alexander B [ORNL; Chisholm, Calum R [ORNL; Zecevic, strahinja [LiOx, Inc., Pasadena, California 91106, United States; Veith, Gabriel M [ORNL; Zawodzinski, Thomas A [ORNL

2013-01-01T23:59:59.000Z

311

Catalysts for lean burn engine exhaust abatement  

DOE Patents (OSTI)

The present invention provides a process for catalytically reducing nitrogen oxides in an exhaust gas stream containing nitrogen oxides and a reductant material by contacting the gas stream under conditions effective to catalytically reduce the nitrogen oxides with a catalyst comprising a aluminum-silicate type material and a minor amount of a metal, the catalyst characterized as having sufficient catalytic activity so as to reduce the nitrogen oxides by at least 60 percent under temperatures within the range of from about 200.degree. C. to about 400.degree. C.

Ott, Kevin C. (Los Alamos, NM); Clark, Noline C. (Jemez Springs, NM); Paffett, Mark T. (Los Alamos, NM)

2003-01-01T23:59:59.000Z

312

Catalysts For Lean Burn Engine Exhaust Abatement  

DOE Patents (OSTI)

The present invention provides a process for catalytically reducing nitrogen oxides in an exhaust gas stream containing nitrogen oxides and a reductant material by contacting the gas stream under conditions effective to catalytically reduce the nitrogen oxides with a catalyst comprising a aluminum-silicate type material and a minor amount of a metal, the catalyst characterized as having sufficient catalytic activity so as to reduce the nitrogen oxides by at least 60 percent under temperatures within the range of from about 200.degree. C. to about 400.degree. C.

Ott, Kevin C. (Los Alamos, NM); Clark, Noline C. (Jemez Springs, NM); Paffett, Mark T. (Los Alamos, NM)

2004-04-06T23:59:59.000Z

313

Novel catalysts for hydrogen fuel cell applications:Final report (FY03-FY05).  

DOE Green Energy (OSTI)

The goal of this project was to develop novel hydrogen-oxidation electrocatalyst materials that contain reduced platinum content compared to traditional catalysts by developing flexible synthesis techniques to fabricate supported catalyst structures, and by verifying electrochemical performance in half cells and ultimately laboratory fuel cells. Synthesis methods were developed for making small, well-defined platinum clusters using zeolite hosts, ion exchange, and controlled calcination/reduction processes. Several factors influence cluster size, and clusters below 1 nm with narrow size distribution have been prepared. To enable electrochemical application, the zeolite pores were filled with electrically-conductive carbon via infiltration with carbon precursors, polymerization/cross-linking, and pyrolysis under inert conditions. The zeolite host was then removed by acid washing, to leave a Pt/C electrocatalyst possessing quasi-zeolitic porosity and Pt clusters of well-controlled size. Plotting electrochemical activity versus pyrolysis temperature typically produces a Gaussian curve, with a peak at ca. 800 C. The poorer relative performances at low and high temperature are due to low electrical conductivity of the carbon matrix, and loss of zeolitic structure combined with Pt sintering, respectively. Cluster sizes measured via adsorption-based methods were consistently larger than those observed by TEM and EXAFS, suggesting , that a fraction of the clusters were inaccessible to the fluid phase. Detailed EXAFS analysis has been performed on selected catalysts and catalyst precursors to monitor trends in cluster size evolution, as well as oxidation states of Pt. Experiments were conducted to probe the electroactive surface area of the Pt clusters. These Pt/C materials had as much as 110 m{sup 2}/g{sub pt} electroactive surface area, an almost 30% improvement over what is commercially (mfg. by ETEK) available (86 m{sup 2}/g{sub pt}). These Pt/C materials also perform qualitatively as well as the ETEK material for the ORR, a non-trivial achievement. A fuel cell test showed that Pt/C outperformed the ETEK material by an average of 50% for a 300 hour test. Increasing surface area decreases the amount of Pt needed in a fuel cell, which translates into cost savings. Furthermore, the increased performance realized in the fuel cell test might ultimately mean less Pt is needed in a fuel cell; this again translates into cost savings. Finally, enhanced long-term stability is a key driver within the fuel cell community as improvements in this area must be realized before fuel cells find their way into the marketplace; these Pt/C materials hold great promise of enhanced stability over time. An external laser desorption ion source was successfully installed on the existing Fourier transform ion-cyclotron resonance (FT-ICR) mass spectrometer. However, operation of this laser ablation source has only generated metal atom ions, no clusters have been found to date. It is believed that this is due to the design of the pulsed-nozzle/laser vaporization chamber. The final experimental configuration and design of the two source housings are described.

Thornberg, Steven Michael; Coker, Eric Nicholas; Jarek, Russell L.; Steen, William Arthur

2005-12-01T23:59:59.000Z

314

Development of a stable cobalt-ruthenium Fisher-Tropsch catalyst. Final report  

DOE Green Energy (OSTI)

The reverse micelle catalyst preparation method has been used to prepare catalysts on four supports: magnesium oxide, carbon, alumina- titania and steamed Y zeolite. These catalysts were not as active as a reference catalyst prepared during previous contracts to Union Carbide Corp. This catalyst was supported on steamed Y zerolite support and was impregnated by a pore-filling method using a nonaqueous solvent. Additional catalysts were prepared via pore- filling impregnation of steamed Y zeolites. These catalysts had levels of cobalt two to three and a half times as high as the original Union Carbide catalyst. On a catalyst volume basis they were much more active than the previous catalyst; on an atom by atom basis the cobalt was about of the same activity, i.e., the high cobalt catalysts` cobalt atoms were not extensively covered over and deactivated by other cobalt atoms. The new, high activity, Y zerolite catalysts were not as stable as the earlier Union Carbide catalyst. However, stability enhancement of these catalysts should be possible, for instance, through adjustment of the quantity and/or type of trace metals present. A primary objective of this work was determination whether small amounts of ruthenium could enhance the activity of the cobalt F-T catalyst. The reverse micelle catalysts were not activated by ruthenium, indeed scanning transmission electronic microscopy (STEM) analysis provided some evidence that ruthenium was not present in the cobalt crystallites. Ruthenium did not seem to activate the high cobalt Y zeolite catalyst either, but additional experiments with Y zeolite-supported catalysts are required. Should ruthenium prove not to be an effective promoter under the simple catalyst activation procedure used in this work, more complex activation procedures have been reported which are claimed to enhance the cobalt/ruthenium interaction and result in activity promotion by ruthenium.

Frame, R.R.; Gala, H.B.

1995-02-01T23:59:59.000Z

315

Fuel Cell Technologies Office: Non-Platinum Electrocatalysts Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

Non-Platinum Electrocatalysts Workshop Non-Platinum Electrocatalysts Workshop The U.S. Department of Energy sponsored the Non-Platinum Electrocatalysts Workshop in New Orleans, Louisiana, March 21-22, 2003. Attendees included researchers, government officials, and industry members. The purpose of the workshop was to review the current status of electrocatalysts for PEM fuel cells, review the impact of platinum cost and availability on PEM fuel cell commercialization, identify potential non-platinum electrocatalysts, develop a strategy to explore the potential development of new, non-platinum electrocatalysts for PEM fuel cell applications. The presentations from the Non-Platinum Electrocatalysts Workshop are available as Adobe Acrobat PDFs. Download Adobe Reader. Overview (PDF 349 KB), Nancy Garland, DOE Fuel Cell Technologies Office

316

De-alloyed platinum nanoparticles  

DOE Patents (OSTI)

A method of producing de-alloyed nanoparticles. In an embodiment, the method comprises admixing metal precursors, freeze-drying, annealing, and de-alloying the nanoparticles in situ. Further, in an embodiment de-alloyed nanoparticle formed by the method, wherein the nanoparticle further comprises a core-shell arrangement. The nanoparticle is suitable for electrocatalytic processes and devices.

Strasser, Peter (Houston, TX); Koh, Shirlaine (Houston, TX); Mani, Prasanna (Houston, TX); Ratndeep, Srivastava (Houston, TX)

2011-08-09T23:59:59.000Z

317

Novel Fischer-Tropsch catalysts  

DOE Patents (OSTI)

Novel polymer-supported metal complexes of the formula: PS --R Me(CO).sub.n H.sub.m where: PS represents a divinylbenzene crosslinked polystyrene in which the divinylbenzene crosslinking is greater than 1% and less than about 18%; R represents a cycloalkadienyl radical of 4 through 6 carbon atoms; Me represents a Group VIII metal; CO represents a carbonyl radical; H represents hydrogen; n represents an integer varying from 0 through 3; m represents an integer varying from 0 through 2 inclusively with the further provision that 2n+m must total 18 when added to the electrons in R and Me, or n+m must total 0; are prepared by: brominating PS --H by treating same with bromine in the presence of a thallium salt in a partially or fully halogenated solvent to form PS --Br; treating said PS --Br so produced with a lithium alkyl of 1 through 12 carbon atoms in an aromatic solvent to produce PS --Li; substituting said PS-- Li so produced by reaction with a 2-cycloalkenone of 4 to 6 carbon atoms in the presence of an ether solvent and using a water work-up to form a cycloalkenylalcohol-substituted PS ; dehydrating said alcohol so produced by heating under a vacuum to produce a cycloalkadienyl-substituted PS ; reacting the cycloalkadienyl-substituted PS with metal carbonyl in the presence of a partially or fully halogenated hydrocarbon, aromatic hydrocarbon of 6 through 8 carbon atoms, ethers, or esters of 4 through 10 carbon atoms as a solvent to produce a polystyrene-supported cycloalkadienyl metal carbonyl. The novel compounds are used as improved Fischer-Tropsch catalysts particularly for the conversion of CO+H.sub.2 to gaseous and liquid hydrocarbons at milder conditions than with prior catalysts.

Vollhardt, Kurt P. C. (Kensington, CA); Perkins, Patrick (Berkeley, CA)

1981-01-01T23:59:59.000Z

318

Novel Fischer-Tropsch catalysts  

DOE Patents (OSTI)

Novel polymer-supported metal complexes of the formula: PS --R Me(CO).sub.n H.sub.m where: PS represents a divinylbenzene crosslinked polystyrene in which the divinylbenzene crosslinking is greater than 1% and less than about 18%; R represents a cycloalkadienyl radical of 4 through 6 carbon atoms; Me represents a Group VIII metal; CO represents a carbonyl radical; H represents hydrogen; n represents an integer varying from 0 through 3; m represents an integer varying from 0 through 2 inclusively with the further provision that 2n+m must total 18 when added to the electrons in R and Me, or n+m must total 0; are prepared by: brominating PS --H by treating same with bromine in the presence of a thallium salt in a partially or fully halogenated solvent to form PS --Br; treating said PS --Br so produced with a lithium alkyl of 1 through 12 carbon atoms in an aromatic solvent to produce PS --Li; substituting said PS-- Li so produced by reaction with a 2-cycloalkenone of 4 to 6 carbon atoms in the presence of an ether solvent and using a water work-up to form a cycloalkenylalcohol-substituted PS ; dehydrating said alcohol so produced by heating under a vacuum to produce a cycloalkadienyl-substituted PS ; reacting the cycloalkadienyl-substituted PS with metal carbonyl in the presence of a partially or fully halogenated hydrocarbon, aromatic hydrocarbon of 6 through 8 carbon atoms, ethers, or esters of 4 through 10 carbon atoms as a solvent to produce a polystyrene-supported cycloalkadienyl metal carbonyl. The novel compounds are used as improved Fischer-Tropsch catalysts particularly for the conversion of CO+H.sub.2 to gaseous and liquid hydrocarbons at milder conditions than with prior catalysts.

Vollhardt, Kurt P. C. (Kensington, CA); Perkins, Patrick (Berkeley, CA)

1980-01-01T23:59:59.000Z

319

Novel Fischer-Tropsch catalysts  

DOE Patents (OSTI)

Novel polymer-supported metal complexes of the formula PS -R Me(CO).sub.n H.sub.m where: PS represents a divinylbenzene crosslinked polystyrene in which the divinylbenzene crosslinking is greater than 1% and less than about 18%; R represents a cycloalkadienyl radical of 4 through 6 carbon atoms; Me represents a Group VIII metal; CO represents a carbonyl radical; H represents hydrogen; n represents an integer varying from 0 through 3; m represents an integer varying from 0 through 2 inclusively with the further provision that 2n+m must total 18 when added to the electrons in R and Me, or n+m must total 0; are prepared by: brominating PS -H by treating same with bromine in the presence of a thallium salt in a partially or fully halogenated solvent to form PS -Br; treating said PS -Br so produced with a lithium alkyl of 1 through 12 carbon atoms in an aromatic solvent to produce PS -Li; substituting said PS - Li so produced by reaction with a 2-cycloalkenone of 4 to 6 carbon atoms in the presence of an ether solvent and using a water work-up to form a cycloalkenylalcohol-substituted PS ; dehydrating said alcohol so produced by heating under a vacuum to produce a cycloalkadienyl-substituted PS ; reacting the cycloalkadienyl-substituted PS with metal carbonyl in the presence of a partially or fully halogenated hydrocarbon, aromatic hydrocarbon of 6 through 8 carbon atoms, ethers, or esters of 4 through 10 carbon atoms as a solvent to produce a polystyrene-supported cycloalkadienyl metal carbonyl. The novel compounds are used as improved Fischer-Tropsch catalysts particularly for the conversion of CO+H.sub.2 to gaseous and liquid hydrocarbons at milder conditions than with prior catalysts.

Vollhardt, Kurt P. C. (Kensington, CA); Perkins, Patrick (Berkeley, CA)

1981-01-01T23:59:59.000Z

320

Attrition Resistant Fischer-Tropsch Catalysts Based on FCC Supports  

SciTech Connect

Commercial spent fluid catalytic cracking (FCC) catalysts provided by Engelhard and Albemarle were used as supports for Fe-based catalysts with the goal of improving the attrition resistance of typical F-T catalysts. Catalysts with the Ruhrchemie composition (100 Fe/5 Cu/4.2 K/25 spent FCC on mass basis) were prepared by wet impregnation. XRD and XANES analysis showed the presence of Fe{sub 2}O{sub 3} in calcined catalysts. FeC{sub x} and Fe{sub 3}O{sub 4} were present in the activated catalysts. The metal composition of the catalysts was analyzed by ICP-MS. F-T activity of the catalysts activated in situ in CO at the same conditions as used prior to the attrition tests was measured using a fixed bed reactor at T = 573 K, P = 1.38 MPa and H{sub 2}:CO ratio of 0.67. Cu and K promoted Fe supported over Engelhard provided spent FCC catalyst shows relatively good attrition resistance (8.2 wt% fines lost), high CO conversion (81%) and C{sub 5}+ hydrocarbons selectivity (18.3%).

Adeyinka Adeyiga

2010-02-05T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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.


321

The role of catalyst activation on the activity and attrition of precipitated iron Fischer-Tropsch catalysts  

DOE Green Energy (OSTI)

The results of this work indicate that magnetite is not catalytically active for Fischer-Tropsch Synthesis (FTS) in precipitated, unsupported iron catalysts, but the formation of the carbide phase is necessary to obtain FTS activity. The transformation of magnetite to carbide, though essential to obtain FTS activity, also causes the catalyst to break down. This can lead to severe problems during operation in a commercial slurry phase reactor. The results presented here imply that activation and attrition are simultaneous and complementary processes. In another study, we show that the catalyst can also under go attrition on a micron scale which is caused by lack of strength of the forces binding the catalyst primary particles in the agglomerates. Both these processes can make wax separation and product recovery extremely difficult. In this study, we have also shown that H{sub 2} reduction of this catalyst to metallic iron is detrimental to subsequent catalyst activity and causes a loss of surface area due to sintering of the iron crystallites. Reduction to metallic Fe also causes impurities such as S to segregate to the surface causing a complete loss of FTS activity. It has been shown that even submonolayer amounts of S can cause a dramatic decrease in FTS activity, hence reduction to metallic Fe should be avoided during activation of these catalysts. We have shown, however, that a mild H{sub 2} reduction to magnetite does not lead to S segregation to the surface, and is therefore acceptable.

Datye, A.K.; Shroff, M.D. [New Mexico Univ., Albuquerque, NM (United States); Harrington, M.S.; Coulter, K.E.; Sault, A.G.; Jackson, N.B. [Sandia National Labs., Albuquerque, NM (United States)

1995-12-31T23:59:59.000Z

322

Method for dispersing catalyst onto particulate material  

DOE Patents (OSTI)

A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal.

Utz, Bruce R. (Pittsburgh, PA); Cugini, Anthony V. (Pittsburgh, PA)

1992-01-01T23:59:59.000Z

323

Homogeneous catalyst formulations for methanol production  

DOE Patents (OSTI)

There is disclosed synthesis of CH.sub.3 OH from carbon monoxide and hydrogen using an extremely active homogeneous catalyst for methanol synthesis directly from synthesis gas. The catalyst operates preferably between 100.degree.-150.degree. C. and preferably at 100-150 psia synthesis gas to produce methanol. Use can be made of syngas mixtures which contain considerable quantities of other gases, such as nitrogen, methane or excess hydrogen. The catalyst is composed of two components: (a) a transition metal carbonyl complex and (b) an alkoxide component. In the simplest formulation, component (a) is a complex of nickel tetracarbonyl and component (b) is methoxide (CH.sub.3 O.sup.-), both being dissolved in a methanol solvent system. The presence of a co-solvent such as p-dioxane, THF, polyalcohols, ethers, hydrocarbons, and crown ethers accelerates the methanol synthesis reaction.

Mahajan, Devinder (Port Jefferson, NY); Sapienza, Richard S. (Shoreham, NY); Slegeir, William A. (Hampton Bays, NY); O' Hare, Thomas E. (Huntington Station, NY)

1991-02-12T23:59:59.000Z

324

Homogeneous catalyst formulations for methanol production  

DOE Patents (OSTI)

There is disclosed synthesis of CH.sub.3 OH from carbon monoxide and hydrogen using an extremely active homogeneous catalyst for methanol synthesis directly from synthesis gas. The catalyst operates preferably between 100.degree.-150.degree. C. and preferably at 100-150 psia synthesis gas to produce methanol. Use can be made of syngas mixtures which contain considerable quantities of other gases, such as nitrogen, methane or excess hydrogen. The catalyst is composed of two components: (a) a transition metal carbonyl complex and (b) an alkoxide component. In the simplest formulation, component (a) is a complex of nickel tetracarbonyl and component (b) is methoxide (CH.sub.3 O.sup.13 ), both being dissolved in a methanol solvent system. The presence of a co-solvent such as p-dioxane, THF, polyalcohols, ethers, hydrocarbons, and crown ethers accelerates the methanol synthesis reaction.

Mahajan, Devinder (Port Jefferson, NY); Sapienza, Richard S. (Shoreham, NY); Slegeir, William A. (Hampton Bays, NY); O' Hare, Thomas E. (Huntington Station, NY)

1990-01-01T23:59:59.000Z

325

Nanostructured catalyst supports  

DOE Patents (OSTI)

The present invention relates to SiC nanostructures, including SiC nanopowder, SiC nanowires, and composites of SiC nanopowder and nanowires, which can be used as catalyst supports in membrane electrode assemblies and in fuel cells. The present invention also relates to composite catalyst supports comprising nanopowder and one or more inorganic nanowires for a membrane electrode assembly.

Zhu, Yimin; Goldman, Jay L.; Qian, Baixin; Stefan, Ionel C.

2012-10-02T23:59:59.000Z

326

Cyano- and polycyanometallo-porphyrins as catalysts for alkane oxidation  

DOE Patents (OSTI)

New compositions of matter comprising cyano-substituted metal complexes of porphyrins are catalysts for the oxidation of alkanes. The metal is iron, chromium, manganese, ruthenium, copper or cobalt. The porphyrin ring has cyano groups attached thereto in meso and/or .beta.-pyrrolic positions.

Ellis, Jr., Paul E. (Downingtown, PA); Lyons, James E. (Wallingford, PA)

1995-01-01T23:59:59.000Z

327

Cyano- and polycyanometallo-porphyrins as catalysts for alkane oxidation  

DOE Patents (OSTI)

New compositions of matter comprising cyano-substituted metal complexes of porphyrins are catalysts for the oxidation of alkanes. The metal is iron, chromium, manganese, ruthenium, copper or cobalt. The porphyrin ring has cyano groups attached thereto in meso and/or [beta]-pyrrolic positions.

Ellis, P.E. Jr.; Lyons, J.E.

1995-01-17T23:59:59.000Z

328

Cyano- and polycyanometallo-porphyrins as catalysts for alkane oxidation  

DOE Patents (OSTI)

New compositions of matter comprising cyano-substituted metal complexes of porphyrins are catalysts for the oxidation of alkanes. The metal is iron, chromium, manganese, ruthenium, copper or cobalt. The porphyrin ring has cyano groups attached thereto in meso and/or .beta.-pyrrolic positions.

Ellis, Jr., Paul E. (Downingtown, PA); Lyons, James E. (Wallingford, PA)

1993-01-01T23:59:59.000Z

329

Cyano- and polycyanometallo-porphyrins as catalysts for alkane oxidation  

DOE Patents (OSTI)

New compositions of matter comprising cyano-substituted metal complexes of porphyrins are catalysts for the oxidation of alkanes. The metal is iron, chromium, manganese, ruthenium, copper or cobalt. The porphyrin ring has cyano groups attached thereto in meso- and/or [beta]-pyrrolic positions.

Ellis, P.E. Jr.; Lyons, J.E.

1993-05-18T23:59:59.000Z

330

Hydrocracking and hydroisomerization of long-chain alkanes and polyolefins over metal-promoted anion-modified transition metal oxides  

DOE Patents (OSTI)

A method of cracking a feedstock by contacting the feedstock with a metal-promoted anion-modified metal oxide catalyst in the presence of hydrogen gas. The metal oxide of the catalyst is one or more of ZrO.sub.2, HfO.sub.2, TiO.sub.2 and SnO.sub.2, and the feedstock is principally chains of at least 20 carbon atoms. The metal-promoted anion-modified metal oxide catalyst contains one or more of Pt, Ni, Pd, Rh, Ir, Ru, (Mn & Fe) or mixtures of them present between about 0.2% to about 15% by weight of the catalyst. The metal-promoted anion-modified metal oxide catalyst contains one or more of SO.sub.4, WO.sub.3, or mixtures of them present between about 0.5% to about 20% by weight of the catalyst.

Venkatesh, Koppampatti R. (Pittsburgh, PA); Hu, Jianli (Cranbury, NJ); Tierney, John W. (Pittsburgh, PA); Wender, Irving (Pittsburgh, PA)

2001-01-01T23:59:59.000Z

331

Hydrocracking and hydroisomerization of long-chain alkanes and polyolefins over metal-promoted anion-modified transition metal oxides  

DOE Patents (OSTI)

A method is described for cracking a feedstock by contacting the feedstock with a metal-promoted anion-modified metal oxide catalyst in the presence of hydrogen gas. The metal oxide of the catalyst is one or more of ZrO{sub 2}, HfO{sub 2}, TiO{sub 2} and SnO{sub 2}, and the feedstock is principally chains of at least 20 carbon atoms. The metal-promoted anion-modified metal oxide catalyst contains one or more of Pt, Ni, Pd, Rh, Ir, Ru, (Mn and Fe) or mixtures of them present between about 0.2% to about 15% by weight of the catalyst. The metal-promoted anion-modified metal oxide catalyst contains one or more of SO{sub 4}, WO{sub 3}, or mixtures of them present between about 0.5% to about 20% by weight of the catalyst.

Venkatesh, Koppampatti R.; Hu, Jianli; Tierney, John W.; Wender, Irving

1996-12-01T23:59:59.000Z

332

Thermochemical Equilibrium Modeling of Selective Catalytic Reduction (SRC) Catalyst Poisons  

Science Conference Proceedings (OSTI)

A previous EPRI publication (1022073) provided a detailed literature review on the propensity of the alkali and alkaline earth metals sodium (Na), potassium (K), calcium (Ca) and the Group (V) elements phosphorus (P) and arsenic (As) to deactivate selective catalytic reduction (SCR) catalysts in commercial flue gas cleaning systems. It also listed the conditions under which such deactivation has been reported. This report extends this earlier work to predict the transformation of SCR catalyst ...

2012-11-01T23:59:59.000Z

333

Catalyst for selective NO.sub.x reduction using hydrocarbons  

DOE Patents (OSTI)

A two phase catalyst is disclosed with one or more transition metals such as Cu, Co, Fe, Ag and Mo supported on a molecular sieve having a pore size not greater than 8 .ANG. along with a stabilizing oxide of one or more of the oxides of Zr, Mo, V, Nb or the rare earths coating the molecular sieve. A method of preparing the two phase catalyst and using same to remediate NO.sub.x in combustion gases is also described.

Marshall, Christopher L. (Naperville, IL); Neylon, Michael K. (Naperville, IL)

2007-05-22T23:59:59.000Z

334

WEB RESOURCE: Platinum Plating of Gas Turbine Components  

Science Conference Proceedings (OSTI)

Feb 25, 2008 ... This web resource describes the process by which gas turbine components are coated at SIFCO's Carrigtwohill plant and the effects of platinum ...

335

Technology development for cobalt F-T catalysts. Topical report No.2, Comparison of patented F-T cobalt catalysts  

DOE Green Energy (OSTI)

Based on the information provided in patents assigned to Gulf, Shell, Exxon, and Statoil, a series of catalysts has been prepared consisting of 12--20 wt. % cobalt, a second metal promoter (Ru or Re), and an oxide promoter such as lanthana, zirconia, or alkali oxide, the support being alumina, silica, or titania. All catalysts have been extensively characterized by different methods. The catalysts have been evaluated in terms of their activity, selectivity both in a fixed bed reactor and in a slurry bubble column reactor, and the results correlated with their physico-chemical properties.

Oukaci, R.; Marcelin, G.; Goodwin, J.G. Jr. [Pittsburgh Univ., PA (United States). Dept. of Chemical and Petroleum Engineering

1995-01-17T23:59:59.000Z

336

Catalyst for microelectromechanical systems microreactors  

DOE Patents (OSTI)

A microreactor comprising a silicon wafer, a multiplicity of microchannels in the silicon wafer, and a catalyst coating the microchannels. In one embodiment the catalyst coating the microchannels comprises a nanostructured material. In another embodiment the catalyst coating the microchannels comprises an aerogel. In another embodiment the catalyst coating the microchannels comprises a solgel. In another embodiment the catalyst coating the microchannels comprises carbon nanotubes.

Morse, Jeffrey D. (Martinez, CA); Sopchak, David A. (Livermore, CA); Upadhye, Ravindra S. (Pleasanton, CA); Reynolds, John G. (San Ramon, CA); Satcher, Joseph H. (Patterson, CA); Gash, Alex E. (Brentwood, CA)

2011-11-15T23:59:59.000Z

337

Catalyst for microelectromechanical systems microreactors  

DOE Patents (OSTI)

A microreactor comprising a silicon wafer, a multiplicity of microchannels in the silicon wafer, and a catalyst coating the microchannels. In one embodiment the catalyst coating the microchannels comprises a nanostructured material. In another embodiment the catalyst coating the microchannels comprises an aerogel. In another embodiment the catalyst coating the microchannels comprises a solgel. In another embodiment the catalyst coating the microchannels comprises carbon nanotubes.

Morse, Jeffrey D. (Martinez, CA); Sopchak, David A. (Livermore, CA); Upadhye, Ravindra S. (Pleasanton, CA); Reynolds, John G. (San Ramon, CA); Satcher, Joseph H. (Patterson, CA); Gash, Alex E. (Brentwood, CA)

2010-06-29T23:59:59.000Z

338

Multizone naphtha reforming process  

Science Conference Proceedings (OSTI)

This patent describes a catalytic reforming process for conversion of a naphtha hydrocarbon at reforming conditions having at least two segregated catalyst zones. The improvement comprises contacting the hydrocarbon in a first zone with a first catalyst comprising tin and at least one platinum group metal deposited on a solid catalyst support followed by contacting in a second zone with a second catalyst comprising at least one metal selected from the group consisting of platinum group metals deposited on a solid catalyst support.

Fleming, B.

1987-05-05T23:59:59.000Z

339

Uranium-Based Catalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Uranium-Based Catalysts S. H. Overbury, Cyrus Riahi-Nezhad, Zongtao Zhang, Sheng Dai, and Jonathan Haire Oak Ridge National Laboratory* P.O. Box 2008 Oak Ridge, Tennessee...

340

Epoxidation catalyst and process  

DOE Patents (OSTI)

Disclosed herein is a catalytic method of converting alkenes to epoxides. This method generally includes reacting alkenes with oxygen in the presence of a specific silver catalyst under conditions suitable to produce a yield of the epoxides. The specific silver catalyst is a silver nanocrystal having a plurality of surface planes, a substantial portion of which is defined by Miller indices of (100). The reaction is performed by charging a suitable reactor with this silver catalyst and then feeding the reactants to the reactor under conditions to carry out the reaction. The reaction may be performed in batch, or as a continuous process that employs a recycle of any unreacted alkenes. The specific silver catalyst has unexpectedly high selectivity for epoxide products. Consequently, this general method (and its various embodiments) will result in extraordinarily high epoxide yields heretofore unattainable.

Linic, Suljo (Ann Arbor, MI); Christopher, Phillip (Ann Arbor, MI)

2010-10-26T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Platinum-Loading Reduction in PEM Fuel Cells - Available ...  

TEM bright-field and dark-field images of a commercial Pt/C catalyst and a nanoscale Pt-embedded tantalum oxide catalyst. ... Energy & Utilities; ...

342

Plasmatron-catalyst system  

DOE Patents (OSTI)

A plasmatron-catalyst system. The system generates hydrogen-rich gas and comprises a plasmatron and at least one catalyst for receiving an output from the plasmatron to produce hydrogen-rich gas. In a preferred embodiment, the plasmatron receives as an input air, fuel and water/steam for use in the reforming process. The system increases the hydrogen yield and decreases the amount of carbon monoxide.

Bromberg, Leslie (Sharon, MA); Cohn, Daniel R. (Chestnut Hill, MA); Rabinovich, Alexander (Swampscott, MA); Alexeev, Nikolai (Moscow, RU)

2007-10-09T23:59:59.000Z

343

Catalytic studies of supported Pd-Au catalysts  

E-Print Network (OSTI)

Although Pd-Au high-surface area catalysts are used in industry to improve activity and selectivity, a thorough understanding of the nature of these enhancements is lacking. A molecular-level understanding of catalytic reactions under actual reaction conditions is the ultimate goal. This thesis is mainly focused on the application of Pd-Au supported catalysts for vinyl acetate synthesis and CO oxidation reactions using highsurface area catalysts. We have attempted to improve the conventional Pd-Au based catalyst by synthesizing novel acetate-based and polymer-based catalysts. The corresponding catalytic reactivity and selectivity were measured and compared to conventional Pd-Au based catalyst systems. Subsequent characterization was performed using characterization techniques, such as, X-ray diffraction (XRD) and transmission electron microscopy (TEM). From our bimetallic catalytic studies, it was evident that the addition of Au to Pd leads to increased reactivity and selectivity. This surface modification is an important factor in the altered reaction kinetics for vinyl acetate (VA) synthesis and CO oxidation reactions. Promoted and unpromoted Pd-Au/SiO2/K+ catalyst were used for VA synthesis and the effect of pre-adsorbed O2, acetic acid and the role of oxygen were explored. The VA reaction rate of novel acetate-based Pd-Au/SiO2 catalyst was 3.5 times higher than conventional Pd-Au catalysts. Also, 100% selectivity was obtained for acetate-based Pd-Au/SiO2 at 130 oC and the VA formation rate was comparable to that of conventional Pd-Au catalysts. Therefore, the acetate-based Pd-Au/SiO2 catalyst seems very promising and can be explored further. Also, Pd(1):Au(4)/SiO2 catalysts demonstrate 100% CO conversion at much lower temperatures (90 oC) compared with other Pd-Au based catalysts. Furthermore, we were successful in obtaining sufficient CO oxidation activity with increased metal loading (5 wt%) and these catalysts did not deactivate under above-ambient reaction temperature conditions, which make 1:4 Pd- Au/SiO2 catalyst a good candidate for further exploration in CO oxidation reactions.

Boopalachandran, Praveenkumar

344

THE OXIDIZING BEHAVIOR OF SOME PLATINUM METAL FLUORIDES  

E-Print Network (OSTI)

iii- IV. The Interaction of Chlorine with the Third-SeriesIV. THE INTERACTION OF CHLORINE WITH THE THIRD-SERIESobserved for solutions of chlorine fluorides in SbF 5 , HS0

Graham, Lionell

2011-01-01T23:59:59.000Z

345

New Process for Separation and Recovery of Platinum Group Metals  

Science Conference Proceedings (OSTI)

2010 Vittorio de Nora Award Winner: Designing Crushing and Grinding Circuits for ... Materialization of Manganese by Selective Precipitation from Used Battery.

346

Platinum Group Metal Oxide Absorption Properties of Perovskite ...  

Science Conference Proceedings (OSTI)

In this study, the absorption properties of various perovskite-type oxide is .... Influence of Different Cooling Structure on Surface Crack of HSLA Steel Plate by

347

Catalyst Modeling and CLEERS - Emissions & Emission Controls...  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalyst Modeling and CLEERS A large part of ORNL's efforts in catalyst research are geared toward model development of catalyst devices and engine systems. Experimental data...

348

Pyrochlore-type catalysts for the reforming of hydrocarbon fuels  

DOE Patents (OSTI)

A method of catalytically reforming a reactant gas mixture using a pyrochlore catalyst material comprised of one or more pyrochlores having the composition A.sub.2-w-xA'.sub.wA''.sub.xB.sub.2-y-zB'.sub.yB''.sub.zO.sub.7-.DELTA.. Distribution of catalytically active metals throughout the structure at the B site creates an active and well dispersed metal locked into place in the crystal structure. This greatly reduces the metal sintering that typically occurs on supported catalysts used in reforming reactions, and reduces deactivation by sulfur and carbon. Further, oxygen mobility may also be enhanced by elemental exchange of promoters at sites in the pyrochlore. The pyrochlore catalyst material may be utilized in catalytic reforming reactions for the conversion of hydrocarbon fuels into synthesis gas (H.sub.2+CO) for fuel cells, among other uses.

Berry, David A. (Morgantown, WV); Shekhawat, Dushyant (Morgantown, WV); Haynes, Daniel (Morgantown, WV); Smith, Mark (Morgantown, WV); Spivey, James J. (Baton Rouge, LA)

2012-03-13T23:59:59.000Z

349

Pyrochlore-type catalysts for the reforming of hydrocarbon fuels  

Science Conference Proceedings (OSTI)

A method of catalytically reforming a reactant gas mixture using a pyrochlore catalyst material comprised of one or more pyrochlores having the composition A.sub.2-w-xA'.sub.wA''.sub.xB.sub.2-y-zB'.sub.yB''.sub.zO.sub.7-.DELTA.. Distribution of catalytically active metals throughout the structure at the B site creates an active and well dispersed metal locked into place in the crystal structure. This greatly reduces the metal sintering that typically occurs on supported catalysts used in reforming reactions, and reduces deactivation by sulfur and carbon. Further, oxygen mobility may also be enhanced by elemental exchange of promoters at sites in the pyrochlore. The pyrochlore catalyst material may be utilized in catalytic reforming reactions for the conversion of hydrocarbon fuels into synthesis gas (H.sub.2+CO) for fuel cells, among other uses.

Berry, David A. (Morgantown, WV); Shekhawat, Dushyant (Morgantown, WV); Haynes, Daniel (Morgantown, WV); Smith, Mark (Morgantown, WV); Spivey, James J. (Baton Rouge, LA)

2012-03-13T23:59:59.000Z

350

Haloporphyrins and their preparation and use as catalysts  

DOE Patents (OSTI)

The invention provides novel catalyst compositions, useful in the oxidation of hydrocarbons with air or oxygen to form hydroxy-group containing compounds and in the decomposition of hydroperoxides to form hydroxy-group containing compounds. The catalysts comprise transition metal complexes of a porphyrin ring having 1 to 12 halogen substituents on the porphyrin ring, at least one of said halogens being in a meso position and/or the catalyst containing no aryl group in a meso position. The compositions are prepared by halogenating a transition metal complex of a porphyrin. In one embodiment, a complex of a porphyrin with a metal whose porphyrin complexes are not active for oxidation of hydrocarbons is halogenated, thereby to obtain a haloporphyrin complex of that metal, the metal is removed from the haloporphyrin complex to obtain the free base form of the haloporphyrin, and a metal such as iron whose porphyrin complexes are active for oxidation of hydrocarbons and for the decomposition of alkyl hydroperoxides is complexed with the free base to obtain an active catalyst for oxidation of hydrocarbons and decomposition of alkyl hydroperoxides.

Ellis, P.E. Jr.; Lyons, J.E.

1997-09-02T23:59:59.000Z

351

Energy Department's New Laboratory at NREL Earns LEED Platinum |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Energy Department's New Laboratory at NREL Earns LEED Platinum Energy Department's New Laboratory at NREL Earns LEED Platinum Energy Department's New Laboratory at NREL Earns LEED Platinum November 1, 2013 - 2:52pm Addthis The Energy Systems Integrations Facility at the Energy Department’s National Renewable Energy Laboratory in Golden, Colorado has received a LEED® (Leadership in Energy and Environmental Design) Platinum designation for new construction by the U.S. Green Building Council. | Photo by Dennis Schroeder, National Renewable Energy Laboratory The Energy Systems Integrations Facility at the Energy Department's National Renewable Energy Laboratory in Golden, Colorado has received a LEED® (Leadership in Energy and Environmental Design) Platinum designation for new construction by the U.S. Green Building Council. | Photo by Dennis

352

Energy Department's New Laboratory at NREL Earns LEED Platinum |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Department's New Laboratory at NREL Earns LEED Platinum Department's New Laboratory at NREL Earns LEED Platinum Energy Department's New Laboratory at NREL Earns LEED Platinum November 1, 2013 - 2:52pm Addthis The Energy Systems Integrations Facility at the Energy Department’s National Renewable Energy Laboratory in Golden, Colorado has received a LEED® (Leadership in Energy and Environmental Design) Platinum designation for new construction by the U.S. Green Building Council. | Photo by Dennis Schroeder, National Renewable Energy Laboratory The Energy Systems Integrations Facility at the Energy Department's National Renewable Energy Laboratory in Golden, Colorado has received a LEED® (Leadership in Energy and Environmental Design) Platinum designation for new construction by the U.S. Green Building Council. | Photo by Dennis

353

Alternative Catalyst Supports Based on Metal Carbides  

Science Conference Proceedings (OSTI)

Addressing Materials Processing Issues for USC Steam Turbines: Cast Versions of ... Co-Production of Pure Hydrogen and Electricity from Coal Syngas via the ...

354

NETL: Gasifipedia  

NLE Websites -- All DOE Office Websites (Extended Search)

like platinum, iron, or nickel, also have catalytic activity. Metal catalysts are used in automobile catalytic converters to reform carbon monoxide (CO) and nitric oxide, for...

355

Metallic Glasses for Electro-Catalytic Applications - Programmaster.org  

Science Conference Proceedings (OSTI)

Motivated by these characteristics, we have explored the use of a number of metallic glasses as electro-catalysts in direct alcohol fuel cells. We demonstrate that ...

356

Water Detritiation: Better SCK-CEN Catalysts for Liquid Phase Catalytic Exchange  

SciTech Connect

A technically and economically sound technology for water detritiation is mandatory for the future of fusion. This technology is expected to be based on water electrolysis and Liquid Phase Catalytic Exchange (LPCE). LPCE requires an efficient hydrophobic catalyst. SCK-CEN invented and developed such a catalyst in the past, which is prepared by depositing platinum on an activated charcoal carrier and mixing it with polytetrafluorethylene as a hydrophobic material. In combination with an appropriate wettable packing, different batches of this catalyst performed very well during years of extensive testing, allowing us to develop the ELEX process for water detritiation at inland reprocessing plants. Recently we succeeded in reproducing this catalyst and preparing a slightly different but clearly ameliorated type. By extrapolation these new results would allow us to obtain, at 40 deg. C and under typical but conservative operating conditions, a decontamination factor of 10000 with a column of less than 3 meters long. Such performances would make this catalyst an excellent candidate for application at JET or ITER. To confirm the performances of our improved catalyst for a longer period of time and in a longer column, we are now starting experiments in a newly built installation and we are collaborating with ICSI, Romania.

Bruggeman, Aime; Braet, Johan; Vanderbiesen, Sven [SCK-CEN (Belgium)

2005-07-15T23:59:59.000Z

357

Supported organoiridium catalysts for alkane dehydrogenation  

DOE Patents (OSTI)

Solid supported organoiridium catalysts, a process for preparing such solid supported organoiridium catalysts, and the use of such solid supported organoiridium catalysts in dehydrogenation reactions of alkanes is provided. The catalysts can be easily recovered and recycled.

Baker, R. Thomas; Sattelberger, Alfred P.; Li, Hongbo

2013-09-03T23:59:59.000Z

358

TECHNOLOGY DEVELOPMENT FOR IRON AND COBALT FISCHER-TROPSCH CATALYSTS  

DOE Green Energy (OSTI)

The impact of activation procedure on the phase composition of precipitated iron Fischer-Tropsch (FT) catalysts has been studied. Catalyst samples taken during activation and FT synthesis have been characterized by Moessbauer spectroscopy. Formation of iron carbide is necessary for high FT activity. Hydrogen activation of precipitated iron catalysts results in reduction to predominantly metallic iron and Fe{sub 3}O{sub 4}. Metallic iron is not stable under FT 3 4 conditions and is rapidly converted to {epsilon}{prime}-Fe{sub 2.2}C. Activation with carbon monoxide or syngas 2.2 with low hydrogen partial pressure reduces catalysts to {chi}-Fe{sub 5}C{sub 2} and a small amount of 5 2 superparamagnetic carbide. Exposure to FT conditions partially oxidizes iron carbide to Fe{sub 3}O{sub 4}; however, catalysts promoted with potassium or potassium and copper maintain a constant carbide content and activity after the initial oxidation. An unpromoted iron catalyst which was activated with carbon monoxide to produce 94% {chi}-Fe{sub 5}C{sub 2}, deactivated rapidly as the carbide was oxidized to Fe{sub 3}O{sub 4}. No difference in activity, stability or deactivation rate was found for {chi}-Fe{sub 5}C{sub 2} and {epsilon}{prime}-Fe{sub 2.2}C.

Burtron H. Davis

1999-04-30T23:59:59.000Z

359

Catalyst, method of making, and reactions using the catalyst  

DOE Patents (OSTI)

The present invention includes a catalyst having a layered structure with, (1) a porous support, (2) a buffer layer, (3) an interfacial layer, and optionally (4) a catalyst layer. The invention also provides a process in which a reactant is converted to a product by passing through a reaction chamber containing the catalyst.

Tonkovich, Anna Lee Y [Pasco, WA; Wang, Yong [Richland, WA; Gao, Yufei [Kennewick, WA

2002-08-27T23:59:59.000Z

360

Catalyst, method of making, and reactions using the catalyst  

DOE Patents (OSTI)

The present invention includes a catalyst having a layered structure with, (1) a porous support, (2) a buffer layer, (3) an interfacial layer, and optionally (4) a catalyst layer. The invention also provides a process in which a reactant is converted to a product by passing through a reaction chamber containing the catalyst.

Tonkovich, Anna Lee Y [Pasco, WA; Wang, Yong [Richland, WA; Gao, Yufei [Kennewick, WA

2009-03-03T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Catalyst, Method Of Making, And Reactions Using The Catalyst  

DOE Patents (OSTI)

The present invention includes a catalyst having a layered structure with, (1) a porous support, (2) a buffer layer, (3) an interfacial layer, and optionally (4) a catalyst layer. The invention also provides a process in which a reactant is converted to a product by passing through a reaction chamber containing the catalyst.

Tonkovich, Anna Lee Y. (Pasco, WA); Wang, Yong (Richland, WA); Gao, Yufei (Kennewick, WA)

2004-07-13T23:59:59.000Z

362

A Theoretical Insight into the Catalytic Effect of a Mixed-Metal Oxide at the Nanometer Level: The Case of the Highly Active metal/CeOx/TiO2 (110) Catalysts  

SciTech Connect

The structural and electronic properties of CeO{sub x} species supported on the rutile TiO{sub 2}(110) surface have been examined by means of periodic density-functional calculations that use a generalized gradient approximation functional including a Hubbard-like type correction. Deposition of Ce atoms leads in a first step to Ce{sup 3+} ions bound to the surface through bridge and in-plane oxygen atoms, the released electrons occupying the Ti 3d empty orbitals. Further addition of Ce and molecular oxygen gives place to Ce{sub 2}O{sub 3} dimers diagonally arranged on the surface, in agreement with the spots observed in the scanning tunnel microscope images. The formation process of CeO{sub x} nanoparticles (NPs) on the TiO{sub 2} surface is highly exothermic and our calculations show that the redox properties of the Ce(III)-Ce(IV) couple are significantly altered when it is supported on TiO{sub 2}. In particular the reactivity against CO/O{sub 2} indicates that on the surface the presence of Ce(III) is favored over Ce(IV) species. Our results also indicate that the CeO{sub x}/TiO{sub 2} interface should be seen like a real mixed-metal oxide rather than a supported NP of ceria. Finally, in the context of the high catalytic activity of the M/CeO{sub x}/TiO{sub 2} (M = Au,Cu,Pt) systems in the water-gas shift reaction, we have examined the dissociation of water on the CeO{sub x}/TiO{sub 2} surface and estimated a barrier as small as 0.04 eV, i.e. {approx}8 times smaller than that computed for a TiO{sub 2} oxygen vacancy. This result agrees with the experimental superior catalytic activity of the M/CeO{sub x}/TiO{sub 2} systems over M/TiO{sub 2}.

Rodriguez, J.A.; Graciani, J.; Plata, J.J.; Sanz, J.F.; Liu, P.

2010-03-14T23:59:59.000Z

363

Core-Protected Platinum Monolayer Shell High-Stability Electrocatalysts for Fuel-Cell Cathodes  

Science Conference Proceedings (OSTI)

Platinum monolayers can act as shells for palladium nanoparticles to lead to electrocatalysts with high activities and an ultralow platinum content, but high platinum utilization. The stability derives from the core protecting the shell from dissolution. In fuel-cell tests, no loss of platinum was observed in 200,000 potential cycles, whereas loss of palladium was significant.

K Sasaki; H Naohara; Y Cai; Y Choi; P Liu; M Vukmirovic; J Wang; R Adzic

2011-12-31T23:59:59.000Z

364

Long-Term Testing of Rhodium-Based Catalysts for Mixed Alcohol Synthesis – 2013 Progress Report  

SciTech Connect

The U.S. Department of Energy’s Pacific Northwest National Laboratory has been conducting research since 2005 to develop a catalyst for the conversion of synthesis gas (carbon monoxide and hydrogen) into mixed alcohols for use in liquid transportation fuels. Initially, research involved screening possible catalysts based on a review of the literature, because at that time, there were no commercial catalysts available. The screening effort resulted in a decision to focus on catalysts containing rhodium and manganese. Subsequent research identified iridium as a key promoter for this catalyst system. Since then, research has continued to improve rhodium/manganese/iridium-based catalysts, optimizing the relative and total concentrations of the three metals, examining baseline catalysts on alternative supports, and examining effects of additional promoters. Testing was continued in FY 2013 to evaluate the performance and long-term stability of the best catalysts tested to date. Three tests were conducted. A long-term test of over 2300 hr duration at a single set of operating conditions was conducted with the best carbon-supported catalyst. A second test of about 650 hr duration at a single set of operating conditions was performed for comparison using the same catalyst formulation on an alternative carbon support. A third test of about 680 hr duration at a single set of operating conditions was performed using the best silica-supported catalyst tested to date.

Gerber, Mark A.; Gray, Michel J.; Thompson, Becky L.

2013-09-23T23:59:59.000Z

365

Intermittency on catalysts  

E-Print Network (OSTI)

The present paper provides an overview of results obtained in four recent papers by the authors. These papers address the problem of intermittency for the Parabolic Anderson Model in a \\emph{time-dependent random medium}, describing the evolution of a ``reactant'' in the presence of a ``catalyst''. Three examples of catalysts are considered: (1) independent simple random walks; (2) symmetric exclusion process; (3) symmetric voter model. The focus is on the annealed Lyapunov exponents, i.e., the exponential growth rates of the successive moments of the reactant. It turns out that these exponents exhibit an interesting dependence on the dimension and on the diffusion constant.

J. Gaertner; F. den Hollander; G. Maillard

2007-06-08T23:59:59.000Z

366

Intermittency on catalysts  

E-Print Network (OSTI)

The present paper provides an overview of results obtained in four recent papers by the authors. These papers address the problem of intermittency for the Parabolic Anderson Model in a \\emph{time-dependent random medium}, describing the evolution of a 'reactant'' in the presence of a ``catalyst''. Three examples of catalysts are considered: (1) independent simple random walks; (2) symmetric exclusion process; (3) symmetric voter model. The focus is on the annealed Lyapunov exponents, i.e., the exponential growth rates of the successive moments of the reactant. It turns out that these exponents exhibit an interesting dependence on the dimension and on the diffusion constant.

Gärtner, J; Maillard, G

2007-01-01T23:59:59.000Z

367

Catalysis Without Precious Metals  

Science Conference Proceedings (OSTI)

Written for chemists in industry and academia, this ready reference and handbook summarizes recent progress in the development of new catalysts that do not require precious metals. The research thus presented points the way to how new catalysts may ultimately supplant the use of precious metals in some types of reactions, while highlighting the remaining challenges. This material is based upon work supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Office of Basic Energy Sciences.

Bullock, R. Morris

2010-11-01T23:59:59.000Z

368

Electrocatalytic Measurement Methodology of Oxide Catalysts Using a Thin-Film Rotating Disk Electrode  

E-Print Network (OSTI)

Transition-metal oxides can exhibit high electrocatalytic activity for reactions such as the oxygen reduction reaction (ORR) in alkaline media. It is often difficult to measure and compare the activities of oxide catalysts ...

Suntivich, Jin

369

Nano Catalysts for Diesel Engine Emission Remediation  

DOE Green Energy (OSTI)

The objective of this project was to develop durable zeolite nanocatalysts with broader operating temperature windows to treat diesel engine emissions to enable diesel engine based equipment and vehicles to meet future regulatory requirements. A second objective was to improve hydrothermal durability of zeolite catalysts to at least 675 C. The results presented in this report show that we have successfully achieved both objectives. Since it is accepted that the first step in NO{sub x} conversion under SCR (selective catalytic reduction) conditions involves NO oxidation to NO{sub 2}, we reasoned that catalyst modification that can enhance NO oxidation at low-temperatures should facilitate NO{sub x} reduction at low temperatures. Considering that Cu-ZSM-5 is a more efficient catalyst than Fe-ZSM-5 at low-temperature, we chose to modify Cu-ZSM-5. It is important to point out that the poor low-temperature efficiency of Fe-ZSM-5 has been shown to be due to selective absorption of NH{sub 3} at low-temperatures rather than poor NO oxidation activity. In view of this, we also reasoned that an increased electron density on copper in Cu-ZSM-5 would inhibit any bonding with NH{sub 3} at low-temperatures. In addition to modified Cu-ZSM-5, we synthesized a series of new heterobimetallic zeolites, by incorporating a secondary metal cation M (Sc{sup 3+}, Fe{sup 3+}, In{sup 3+}, and La{sup 3+}) in Cu exchanged ZSM-5, zeolite-beta, and SSZ-13 zeolites under carefully controlled experimental conditions. Characterization by diffuse-reflectance ultra-violet-visible spectroscopy (UV-Vis), X-ray powder diffraction (XRD), extended X-ray absorption fine structure spectroscopy (EXAFS) and electron paramagnetic resonance spectroscopy (EPR) does not permit conclusive structural determination but supports the proposal that M{sup 3+} has been incorporated in the vicinity of Cu(II). The protocols for degreening catalysts, testing under various operating conditions, and accelerated aging conditions were provided by our collaborators at John Deere Power Systems. Among various zeolites reported here, CuFe-SSZ-13 offers the best NO{sub x} conversion activity in 150-650 C range and is hydrothermally stable when tested under accelerated aging conditions. It is important to note that Cu-SSZ-13 is now a commercial catalyst for NO{sub x} treatment on diesel passenger vehicles. Thus, our catalyst performs better than the commercial catalyst under fast SCR conditions. We initially focused on fast SCR tests to enable us to screen catalysts rapidly. Only the catalysts that exhibit high NO{sub x} conversion at low temperatures are selected for screening under varying NO{sub 2}:NO{sub x} ratio. The detailed tests of CuFe-SSZ-13 show that CuFe-SSZ-13 is more effective than commercial Cu-SSZ-13 even at NO{sub 2}:NO{sub x} ratio of 0.1. The mechanistic studies, employing stop-flow diffuse reflectance FTIR spectroscopy (DRIFTS), suggest that high concentration of NO{sup +}, generated by heterobimetallic zeolites, is probably responsible for their superior low temperature NO{sub x} activity. The results described in this report clearly show that we have successfully completed the first step in a new emission treatment catalyst which is synthesis and laboratory testing employing simulated exhaust. The next step in the catalyst development is engine testing. Efforts are in progress to obtain follow-on funding to carry out scale-up and engine testing to facilitate commercialization of this technology.

Narula, Chaitanya Kumar [ORNL; Yang, Xiaofan [ORNL; Debusk, Melanie Moses [ORNL; Mullins, David R [ORNL; Mahurin, Shannon Mark [ORNL; Wu, Zili [ORNL

2012-06-01T23:59:59.000Z

370

Modeling of on-line catalyst addition effects in a short contact time reactor  

Science Conference Proceedings (OSTI)

Recently developed short-contact-time reactors (SCTR), consisting of porous alumina monoliths coated with platinum, have been shown to produce ethylene from rich ethane/oxygen(hydrogen) mixtures with yields and selectivities comparable to conventional steam cracking, using a reactor of much smaller size. Although the overall mechanism is clearly autothermal and catalytic, the details, in particular the relative contributions of heterogeneous and homogeneous chemistry, are a matter of considerable debate. Recent experiments show that reactor performance can be further enhanced by dripping a dilute platinum solution onto the SCTR front face during reaction, resulting in catalyst deposition within only a short (several millimeter) zone of the reactor. The authors have undertaken a computational study of this system, using two-dimensional computational fluid dynamics simulations with full heat and mass transport and detailed heterogeneous and homogeneous kinetic mechanisms. The results indicate that front-face catalyst loading enhances reactor performance by limiting the opportunity for heterogeneous ethane reactions that produce methane. As a result, ethylene selectivity increases and CH{sub 4} selectivity decreases. The results strongly support a mechanism recently proposed by the authors, in which rapid, heterogeneous oxidation of adsorbed hydrogen consumes most of the oxygen. The resulting heat is then released to the gas phase, causing homogeneous pyrolysis of ethane to occur in an environment containing much less oxygen. This mechanism explains not only the effects of on-line catalyst addition, but also the increase in ethylene selectivity observed upon addition of hydrogen to the reactant mixture.

D. K. Zerkle; M. d. Allendorf; M. Wolf; O. Deutschmann

2000-07-30T23:59:59.000Z

371

Stabilization of Electrocatalytic Metal Nanoparticles at Metal-Metal Oxide-Graphene Triple Junction Points  

DOE Green Energy (OSTI)

Carbon-supported metal catalysts are widely used in heterogeneous catalysis and electrocatalysis. In this paper, we report a novel method to deposit metal catalysts and metal oxide nanoparticles on two-dimensional graphene sheets to improve the catalytic performance and stability of the catalyst materials. The new synthesis method allows indium tin oxide (ITO) nanocrystals to be directly grown on functionalized graphene sheets forming the ITO-graphene hybrids. Pt nanoparticles are then deposited to form a special triple-junction structure (Pt-ITO-graphene). Both experimental study and periodic density functional theory calculations show that the supported Pt nanoparticles are stable at Pt-ITO-graphene triple junction points. The new catalyst materials were tested for oxygen reduction for potential applications in polymer electrolyte membrane fuel cells, and they exhibited greatly enhanced stability and activity. The reasons for the high stability and activity of Pt-ITO-graphene are analyzed.

Kou, Rong; Shao, Yuyan; Mei, Donghai; Nie, Zimin; Wang, Donghai; Wang, Chong M.; Viswanathan, Vilayanur V.; Park, Seh K.; Aksay, Ilhan A.; Lin, Yuehe; Wang, Yong; Liu, Jun

2011-03-02T23:59:59.000Z

372

Zinc sulfide liquefaction catalyst  

DOE Patents (OSTI)

A process for the liquefaction of carbonaceous material, such as coal, is set forth wherein coal is liquefied in a catalytic solvent refining reaction wherein an activated zinc sulfide catalyst is utilized which is activated by hydrogenation in a coal derived process solvent in the absence of coal.

Garg, Diwakar (Macungie, PA)

1984-01-01T23:59:59.000Z

373

Sulfur condensation in Claus catalyst  

SciTech Connect

The heterogeneous reactions in which catalyst deactivation by pore plugging occur are listed and include: coke formation in petroleum processing, especially hydrocracking and hydrodesulfurization catalysts; steam reforming and methnation catalysts; ammonia synthesis catalyst; and automobile exhause catalysts. The authors explain how the Claus process converts hydrogen sulfide produced by petroleum desulfurization units and gas treatment processes into elemental sulfur and water. More than 15 million tons of sulfur are recovered annually by this process. Commercial Claus plants appear to operate at thermodynamic equilibrium. Depending on the H2S content of the feed and the number of reactors, total H2S conversion to elemental sulfur can exceed 95%.

Schoffs, G.R.

1985-02-01T23:59:59.000Z

374

Molybdenum sulfide/carbide catalysts  

DOE Patents (OSTI)

The present invention provides methods of synthesizing molybdenum disulfide (MoS.sub.2) and carbon-containing molybdenum disulfide (MoS.sub.2-xC.sub.x) catalysts that exhibit improved catalytic activity for hydrotreating reactions involving hydrodesulfurization, hydrodenitrogenation, and hydrogenation. The present invention also concerns the resulting catalysts. Furthermore, the invention concerns the promotion of these catalysts with Co, Ni, Fe, and/or Ru sulfides to create catalysts with greater activity, for hydrotreating reactions, than conventional catalysts such as cobalt molybdate on alumina support.

Alonso, Gabriel (Chihuahua, MX); Chianelli, Russell R. (El Paso, TX); Fuentes, Sergio (Ensenada, MX); Torres, Brenda (El Paso, TX)

2007-05-29T23:59:59.000Z

375

Accelerated deployment of nanostructured hydrotreating catalysts. Final CRADA Report.  

Science Conference Proceedings (OSTI)

Nanomanufacturing offers an opportunity to create domestic jobs and facilitate economic growth. In response to this need, U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy issued a Research Call to develop nanomanufacturing capabilities at the National Laboratories. High performance catalysts represent a unique opportunity to deploy nanomanufacturing technologies. Re-refining of used lube oil offers an opportunity to create manufacturing jobs and decrease dependence on imported petroleum. Improved catalysts are required to produce a better quality product, decrease environmental impact, extend catalyst life, and improve overall economics of lube oil re-refining. Argonne National Laboratory (Argonne) in cooperation with Universal Lubricants, Inc. (ULI) and Chemical Engineering Partners (CEP) have carried out a Cooperative Research and Development Agreement (CRADA) to prepare nanostructured hydrotreating catalysts using atomic layer deposition (ALD) to exhibit superior performance for the re-refining of used lube oil. We investigated the upgrading of recycled lube oil by hydrogenation using commercial, synthetically-modified commercial catalysts, and synthesized catalysts. A down-flow (trickle bed) catalytic unit was used for the hydrogenation experiments. In addition to carrying out elemental analyses of the various feed and product fractions, characterization was undertaken using H{sup 1} and C{sup 13} NMR. Initially commercial were evaluated. Second these commercial catalysts were promoted with precious metals using atomic layer deposition (ALD). Performance improvements were observed that declined with catalyst aging. An alternate approach was undertaken to deeply upgrade ULI product oils. Using a synthesized catalyst, much lower hydrogenation temperatures were required than commercial catalysts. Other performance improvements were also observed. The resulting lube oil fractions were of high purity even at low reaction severity. The products recovered from both the ALD and other processes were water-white (even those from the low temperature, low residence time (high space velocity), low conversion runs). These results indicate that highly upgraded recycle lube oils can be produced using ALD-deposited active metal catalysts. The use of H{sup 1} and C{sup 13} NMR for the characterization of the treated lube oils has been shown to be effective.

Libera, J.A.; Snyder, S.W.; Mane, A.; Elam, J.W.; Cronauer, D.C.; Muntean, J.A.; Wu, T.; Miller, J.T. (Chemical Sciences and Engineering Division); ( ES)

2012-08-27T23:59:59.000Z

376

Review of Novel Catalysts for Biomass Tar Cracking and Methane Reforming  

DOE Green Energy (OSTI)

A review of the literature was conducted to examine the performance of catalysts other than conventional nickel catalysts, and alkaline earth and olivine based catalysts for treating hot raw product gas from a biomass gasifier to convert methane and tars into synthesis gas. Metal catalysts other than Ni included precious metals Rh, Ru, Ir, Pt, and Pd, as well as Cu, Co, and Fe in limited testing. Nickel catalysts promoted with Rh, Zr, Mn, Mo, Ti, Ag, or Sn were also examined, as were Ni catalysts on Ce2O3, TiO2, ZrO2, SiO2, and La2O3. In general, Rh stood out as a consistently superior metal catalyst for methane reforming, tar cracking, and minimizing carbon buildup on the catalyst. Ru and Ir also showed significant improvement over Ni for methane reforming. Ceria stood out as good support material and particularly good promoter material when added in small quantities to another support material such as alumina, zirconia, or olivine. Other promising supports were lanthana, zirconia, and titania.

Gerber, Mark A.

2007-10-10T23:59:59.000Z

377

Project Catalyst | Open Energy Information  

Open Energy Info (EERE)

Project Catalyst Project Catalyst Jump to: navigation, search Name Project Catalyst Agency/Company /Organization ClimateWorks, European Climate Foundation Sector Climate, Energy, Land Focus Area Energy Efficiency, Forestry Website http://www.project-catalyst.in References Project Catalyst[1] Project Catalyst Screenshot Contents 1 About 2 Resources 2.1 Tools 2.2 Programs 3 References About "Project Catalyst is an initiative of the ClimateWorks Foundation. ClimateWorks is a global, nonprofit philanthropic foundation headquartered in San Francisco, California with a network of affiliated foundations in China, India, the US, and the European Union. The ClimateWorks family of organizations focus on enacting policies that reduce greenhouse gas emissions through three general policy areas: energy efficiency standards,

378

Optimization of Rhodium-Based Catalysts for Mixed Alcohol Synthesis -- 2011 Progress Report  

SciTech Connect

Pacific Northwest National Laboratory has been conducting research to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). In recent years, this research has primarily involved the further development of catalysts containing rhodium and manganese based on the results of earlier catalyst screening tests. Research during FY 2011 continued to examine the performance of RhMn catalysts on alternative supports including selected zeolite, silica, and carbon supports. Catalyst optimization continued using both the Davisil 645 and Merck Grade 7734 silica supports. Research also was initiated in FY 2011, using the both Davisil 645 silica and Hyperion CS-02C-063 carbon supports, to evaluate the potential for further improving catalyst performance, through the addition of one or two additional metals as promoters to the catalysts containing Rh, Mn, and Ir.

Gerber, Mark A.; Gray, Michel J.; Albrecht, Karl O.; Rummel, Becky L.

2011-10-01T23:59:59.000Z

379

Fischer-Tropsch activity for non-promoted cobalt-on-alumina catalysts  

DOE Green Energy (OSTI)

Cobalt catalysts, and processes employing these inventive catalysts, for hydrocarbon synthesis. The inventive catalyst comprises cobalt on an alumina support and is not promoted with any noble or near noble metals. In one aspect of the invention, the alumina support preferably includes a dopant in an amount effective for increasing the activity of the inventive catalyst. The dopant is preferably a titanium dopant. In another aspect of the invention, the cobalt catalyst is preferably reduced in the presence of hydrogen at a water vapor partial pressure effective to increase the activity of the cobalt catalyst for hydrocarbon synthesis. The water vapor partial pressure is preferably in the range of from 0 to about 0.1 atmospheres.

Singleton, Alan H. (Baden, PA); Oukaci, Rachid (Gibsonia, PA); Goodwin, James G. (Gibsonia, PA)

2001-01-01T23:59:59.000Z

380

Development of inexpensive metal macrocyclic complexes for use in fuel cells  

DOE Green Energy (OSTI)

Several metal macrocyclic complexes were synthesized for use as catalysts in fuel cells. An initial evaluation of their ability to catalyze the fuel cell reactions were completed. Based on this initial evaluation, one metal macrocyclic catalyst was selected and long-term stability testing in a fuel cell was initiated. The fuel cell employing this catalyst was operated continuously for one year with little signs of catalyst degradation. The effect of synthetic reformates on the performance of the catalyst in the fuel cell environment also demonstrated high tolerance of this catalyst for common contaminants and poisons.

Doddapaneni, N.; Ingersoll, D. [Sandia National Labs., Albuquerque, NM (United States). Lithium Battery Research and Development Dept.; Kosek, J.A.; Cropley, C.C.; Hamdan, M. [Giner, Inc., Waltham, MA (United States)

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Synthesis, Characterization, and Cytotoxicity of Platinum(IV) Carbamate Complexes  

E-Print Network (OSTI)

The synthesis, characterization, and cytotoxicity of eight new platinum(IV) complexes having the general formula cis,cis,trans-[Pt(NH[subscript 3)[subscript 2]Cl[subscript 2](O[subscript 2]CNHR)[subscript 2

Wilson, Justin Jeff

382

Electrodeposition of Technetium on Platinum for Thermal Ionization Mass Spectrometry (TIMS)  

Science Conference Proceedings (OSTI)

A novel device has been fabricated for the electrodeposition of technetium metal onto platinum filaments for thermal ionization mass spectrometric (TIMS) measurements. The ability of the device to focus the deposition to diameters of hundreds of micrometers on pre-mounted TIMS filaments coupled with the ease of use and simplicity of design permit for an extremely sensitive yet economical TIMS filament loading technique. Electrodeposition parameters were varied in order to maximize deposition efficiency. X-ray photoelectron spectroscopy (XPS) was used to confirm and characterize the technetium deposit. The technetium is deposited in the metallic state, although surface oxides in the 4+ and 7+ state form readily. Initial TIMS measurements of the electrodeposited technetium in the presence of a barium sulfate ionization enhancer show potential for excellent sensitivity.

Engelmann, Mark D.; Metz, Lori A.; Delmore, James E.; Engelhard, Mark H.; Ballou, Nathan E.

2008-05-15T23:59:59.000Z

383

Catalyst for elemental sulfur recovery process  

DOE Patents (OSTI)

A catalytic reduction process is described for the direct recovery of elemental sulfur from various SO[sub 2]-containing industrial gas streams. The catalytic process provides high activity and selectivity, as well as stability in the reaction atmosphere, for the reduction of SO[sub 2] to elemental sulfur product with carbon monoxide or other reducing gases. The reaction of sulfur dioxide and reducing gas takes place over a metal oxide composite catalyst having one of the following empirical formulas: [(FO[sub 2])[sub 1[minus]n](RO)[sub n

Flytzani-Stephanopoulos, M.; Liu, W.

1995-01-24T23:59:59.000Z

384

Binary ferrihydrite catalysts  

DOE Patents (OSTI)

A method of preparing a catalyst precursor comprises dissolving an iron salt and a salt of an oxoanion forming agent, in water so that a solution of the iron salt and oxoanion forming agent salt has a ratio of oxoanion/Fe of between 0.0001:1 to 0.5:1. Next is increasing the pH of the solution to 10 by adding a strong base followed by collecting of precipitate having a binary ferrihydrite structure. A binary ferrihydrite catalyst precursor is also prepared by dissolving an iron salt in water. The solution is brought to a pH of substantially 10 to obtain ferrihydrite precipitate. The precipitate is then filtered and washed with distilled water and subsequently admixed with a hydroxy carboxylic acid solution. The admixture is mixed/agitated and the binary ferrihydrite precipitate is then filtered and recovered. 3 figs.

Huffman, G.P.; Zhao, J.; Feng, Z.

1996-12-03T23:59:59.000Z

385

Fluorination process using catalysts  

DOE Patents (OSTI)

A process is given for converting an actinide compound selected from the group consisting of uranium oxides, plutonium oxides, uranium tetrafluorides, plutonium tetrafluorides and mixtures of said oxides and tetrafluorides, to the corresponding volatile actinide hexafluoride by fluorination with a stoichiometric excess of fluorine gas. The improvement involves conducting the fluorination of the plutonium compounds in the presence of a fluoride catalyst selected from the group consisting of CoF/sub 3/, AgF/sub 2/ and NiF/sub 2/, whereby the fluorination is significantly enhanced. The improvement also involves conducting the fluorination of one of the uranium compounds in the presence of a fluoride catalyst selected from the group consisting of CoF/sub 3/ and AgF/sub 2/, whereby the fluorination is significantly enhanced.

Hochel, R.C.; Saturday, K.A.

1983-08-25T23:59:59.000Z

386

Binary ferrihydrite catalysts  

DOE Patents (OSTI)

A method of preparing a catalyst precursor comprises dissolving an iron salt and a salt of an oxoanion forming agent, in water so that a solution of the iron salt and oxoanion forming agent salt has a ratio of oxoanion/Fe of between 0.0001:1 to 0.5:1. Next is increasing the pH of the solution to 10 by adding a strong base followed by collecting of precipitate having a binary ferrihydrite structure. A binary ferrihydrite catalyst precursor is also prepared by dissolving an iron salt in water. The solution is brought to a pH of substantially 10 to obtain ferrihydrite precipitate. The precipitate is then filtered and washed with distilled water and subsequently admixed with a hydroxy carboxylic acid solution. The admixture is mixed/agitated and the binary ferrihydrite precipitate is then filtered and recovered.

Huffman, Gerald P. (Lexington, KY); Zhao, Jianmin (Lexington, KY); Feng, Zhen (Lexington, KY)

1996-01-01T23:59:59.000Z

387

Fluorination process using catalyst  

DOE Patents (OSTI)

A process for converting an actinide compound selected from the group consisting of uranium oxides, plutonium oxides, uranium tetrafluorides, plutonium tetrafluorides and mixtures of said oxides and tetrafluorides, to the corresponding volatile actinide hexafluoride by fluorination with a stoichiometric excess of fluorine gas. The improvement involves conducting the fluorination of the plutonium compounds in the presence of a fluoride catalyst selected from the group consisting of CoF.sub.3, AgF.sub.2 and NiF.sub.2, whereby the fluorination is significantly enhanced. The improvement also involves conducting the fluorination of one of the uranium compounds in the presence of a fluoride catalyst selected from the group consisting of CoF.sub.3 and AgF.sub.2, whereby the fluorination is significantly enhanced.

Hochel, Robert C. (Aiken, SC); Saturday, Kathy A. (Aiken, SC)

1985-01-01T23:59:59.000Z

388

Nanoporous Au: an unsupported pure gold catalyst?  

Science Conference Proceedings (OSTI)

The unique properties of gold especially in low temperature CO oxidation have been ascribed to a combination of various effects. In particular, particle sizes below a few nm and specific particle-support interactions have been shown to play important roles. On the contrary, recent reports revealed that monolithic nanoporous gold (npAu) prepared by leaching a less noble metal, such as Ag, out of the corresponding alloy can also exhibit remarkably high catalytic activity for CO oxidation, even though no support is present. Therefore, it was claimed to be a pure and unsupported gold catalyst. We investigated npAu with respect to its morphology, surface composition and catalytic properties. In particular, we studied the reaction kinetics for low temperature CO oxidation in detail taking mass transport limitation due to the porous structure of the material into account. Our results reveal that Ag, even if removed almost completely from the bulk, segregates to the surface resulting in surface concentrations of up to 10 at%. Our data suggest that this Ag plays a significant role in activation of molecular oxygen. Therefore, npAu should be considered as a bimetallic catalyst rather than a pure Au catalyst.

Wittstock, A; Neumann, B; Schaefer, A; Dumbuya, K; Kuebel, C; Biener, M; Zielasek, V; Steinrueck, H; Gottfried, M; Biener, J; Hamza, A; B?umer, M

2008-09-04T23:59:59.000Z

389

Non-Platinum Bimetallic Cathode Electrocatalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Cost: lowering PGM loading by replacing PGM in electrocatalyst particle core with base metal - C. Electrode performance: modifying surface electronic properties to enhance ORR...

390

Catalyst systems and uses thereof  

DOE Patents (OSTI)

A method of carbon monoxide (CO) removal comprises providing an oxidation catalyst comprising cobalt supported on an inorganic oxide. The method further comprises feeding a gaseous stream comprising CO, and oxygen (O.sub.2) to the catalyst system, and removing CO from the gaseous stream by oxidizing the CO to carbon dioxide (CO.sub.2) in the presence of the oxidation catalyst at a temperature between about 20 to about 200.degree. C.

Ozkan, Umit S. (Worthington, OH); Holmgreen, Erik M. (Columbus, OH); Yung, Matthew M. (Columbus, OH)

2012-07-24T23:59:59.000Z

391

Fuel cell applications for novel metalloporphyrin catalysts  

DOE Green Energy (OSTI)

This project utilized Computer-Aided Molecular Design (CAMD) to develop a new class of metalloporphyrin materials for use as catalysts for two fuel cell reactions. The first reaction is the reduction of oxygen at the fuel cell cathode, and this reaction was the main focus of the research. The second reaction we attempted to catalyze was the oxidation of methanol at the anode. Two classes of novel metalloporphyrins were developed. The first class comprised the dodecaphenylporphyrins whose steric bulk forces them into a non-planar geometry having a pocket where oxygen or methanol is more tightly bound to the porphyrin than it is in the case of planar porphyrins. Significant improvements in the catalytic reduction of oxygen by the dodecaphenyl porphyrins were measured in electrochemical cells. The dodecaphenylporphyrins were further modified by fluorinating the peripheral phenyl groups to varying degrees. The fluorination strongly affected their redox potential, but no effect on their catalytic activity towards oxygen was observed. The second class of porphyrin catalysts was a series of hydrogen-bonding porphyrins whose interaction with oxygen is enhanced. Enhancements in the interaction of oxygen with the porphyrins having hydrogen bonding groups were observed spectroscopically. Computer modeling was performed using Molecular Simulations new CERIUS2 Version 1.6 and a research version of POLYGRAF from Bill Goddard`s research group at the California Institute of Technology. We reoptimized the force field because of an error that was in POLYGRAF and corrected a problem in treatment of the metal in early versions of the program. This improved force field was reported in a J. Am. Chem. Soc. manuscript. Experimental measurements made on the newly developed catalysts included the electrochemical testing in a fuel cell configuration and spectroscopic measurements (UV-Vis, Raman and XPS) to characterize the catalysts.

Ryba, G.; Shelnutt, J.; Doddapaneni, N.; Zavadil, K.

1997-04-01T23:59:59.000Z

392

Catalyst Renewables | Open Energy Information  

Open Energy Info (EERE)

Zip 75204 Product Pursue projects with low technical risk, stable fuel supply and prices, and long-term power purchase agreements References Catalyst Renewables1 LinkedIn...

393

Mixed Alcohol Synthesis Catalyst Screening  

DOE Green Energy (OSTI)

National Renewable Energy Laboratory (NREL) and Pacific Northwest National Laboratory (PNNL) are conducting research to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). PNNL is tasked with obtaining commercially available or preparing promising mixed-alcohol catalysts and screening them in a laboratory-scale reactor system. Commercially available catalysts and the most promising experimental catalysts are provided to NREL for testing using a slipstream from a pilot-scale biomass gasifier. From the standpoint of producing C2+ alcohols as the major product, it appears that the rhodium catalyst is the best choice in terms of both selectivity and space-time yield (STY). However, unless the rhodium catalyst can be improved to provide minimally acceptable STYs for commercial operation, mixed alcohol synthesis will involve significant production of other liquid coproducts. The modified Fischer-Tropsch catalyst shows the most promise for providing both an acceptable selectivity to C2+ alcohols and total liquid STY. However, further optimization of the Fischer-Tropsch catalysts to improve selectivity to higher alcohols is highly desired. Selection of a preferred catalyst will likely entail a decision on the preferred coproduct slate. No other catalysts tested appear amenable to the significant improvements needed for acceptable STYs.

Gerber, Mark A.; White, James F.; Stevens, Don J.

2007-09-03T23:59:59.000Z

394

Final technical report. Bimetallic complexes as methanol oxidation catalysts  

DOE Green Energy (OSTI)

Our work on the electrocatalyzed oxidation of methanol was initially motivated by the interest in methanol as an anodic reactant in fuel cells. The literature on electrochemical oxidation of alcohols can be roughly grouped into two sets: fuel cell studies and inorganic chemistry studies. Work on fuel cells primarily focuses on surface-catalyzed oxidation at bulk metal anodes, usually Pt or Pt/Ru alloys. In the surface science/electrochemistry approach to these studies, single molecule catalysts are generally not considered. In contrast, the inorganic community investigates the electrooxidation of alcohols in homogeneous systems. Ruthenium complexes have been the most common catalysts in these studies. The alcohol substrates are typically either secondary alcohols (e.g., isopropanol) such that the reaction stops after 2 e{sup -} oxidation to the aldehyde and 4 e{sup -} oxidation to the carboxylic acid can be observed. Methanol, which can also undergo 6 e{sup -} oxidation to CO{sub 2}, rarely appears in the homogeneous catalysis studies. Surface studies have shown that two types of metal centers with different functions result in more effective catalysts than a single metal; however, application of this concept to homogeneous systems has not been demonstrated. The major thrust of the work is to apply this insight from the surface studies to homogeneous catalysis. Even though homogeneous systems would not be appropriate models for active sites on Pt/Ru anodes, it is possible that heterobimetallic catalysts could also utilize two metal centers for different roles. Starting from that perspective, this work involves the preparation and investigation of heterobinuclear catalysts for the electrochemical oxidation of methanol.

McElwee-White, Lisa

2002-01-21T23:59:59.000Z

395

Water Uptake in PEMFC Catalyst Layers  

E-Print Network (OSTI)

Water Uptake in PEMFC Catalyst Layers H. P. Gunterman, a A.membrane fuel-cell catalyst layers are characterized in thecurves indicate that the catalyst layers tested are highly

Gunterman, Haluna P.

2013-01-01T23:59:59.000Z

396

Investigating the effects of proton exchange membrane fuel cell conditions on carbon supported platinum electrocatalyst composition and performance  

SciTech Connect

Changes that carbon-supported platinum electrocatalysts undergo in a proton exchange membrane fuel cell environment were simulated by ex situ heat treatment of catalyst powder samples at 150 #2;C and 100% relative humidity. In order to study modifications that are introduced to chemistry, morphology, and performance of electrocatalysts, XPS, HREELS and three-electrode rotating disk electrode experiments were performed. Before heat treatment, graphitic content varied by 20% among samples with different types of carbon supports, with distinct differences between bulk and surface compositions within each sample. Following the aging protocol, the bulk and surface chemistry of the samples were similar, with graphite content increasing or remaining constant and Pt-carbide decreasing for all samples. From the correlation of changes in chemical composition and losses in performance of the electrocatalysts, we conclude that relative distribution of Pt particles on graphitic and amorphous carbon is as important for electrocatalytic activity as the absolute amount of graphitic carbon present

Patel, Anant; Artyushkova, Kateryna; Atanassov, Plamen; Colbow, Vesna; Dutta, Monica; Harvey, Davie; Wessel, Silvia

2012-04-01T23:59:59.000Z

397

Investigating the effects of proton exchange membrane fuel cell conditions on carbon supported platinum electrocatalyst composition and performance  

DOE Green Energy (OSTI)

Changes that carbon-supported platinum electrocatalysts undergo in a proton exchange membrane fuel cell environment were simulated by ex situ heat treatment of catalyst powder samples at 150 C and 100% relative humidity. In order to study modifications that are introduced to chemistry, morphology, and performance of electrocatalysts, XPS, HREELS and three-electrode rotating disk electrode experiments were performed. Before heat treatment, graphitic content varied by 20% among samples with different types of carbon supports, with distinct differences between bulk and surface compositions within each sample. Following the aging protocol, the bulk and surface chemistry of the samples were similar, with graphite content increasing or remaining constant and Pt-carbide decreasing for all samples. From the correlation of changes in chemical composition and losses in performance of the electrocatalysts, we conclude that relative distribution of Pt particles on graphitic and amorphous carbon is as important for electrocatalytic activity as the absolute amount of graphitic carbon present

A. Patel; K. Artyushkova; P. Atanassov; V. Colbow; M. Dutta; D. Harvey; S. Wessel

2012-04-30T23:59:59.000Z

398

Cisco Catalyst 4503-E, Catalyst 4506-E, Catalyst 4507R-E ...  

Science Conference Proceedings (OSTI)

... The following figures illustrate the installation of the opacity shields for each platform. Figure 5: Catalyst 4503-E Opacity Shield Installation Page 23. ...

2013-07-18T23:59:59.000Z

399

Narrow (n,m)-Distribution of Single-Walled Carbon Nanotubes Grown Using a Solid Supported Catalyst  

E-Print Network (OSTI)

and carbon nanotubes occurs on unsupported iron catalyst clusters formed in situ by the gas- phase was centrifuged for 1 h at 72 600g to separate metallic catalyst particles and suspended tube bundles from at the bottom of the centrifuge tube. Finally, the supernatant liquid, enriched in individual surfactant

Resasco, Daniel

400

Novel Reforming Catalysts  

Science Conference Proceedings (OSTI)

Aqueous phase reforming is useful for processing oxygenated hydrocarbons to hydrogen and other more useful products. Current processing is hampered by the fact that oxide based catalysts are not stable under high temperature hydrothermal conditions. Silica in the form of structured MCM-41 is thermally a more stable support for Co and Ni than conventional high surface area amorphous silica but hydrothermal stability is not demonstrated. Carbon nanotube supports, in contrast, are highly stable under hydrothermal reaction conditions. In this project we show that carbon nanotubes are stable high activity/selectivity supports for the conversion of ethylene glycol to hydrogen.

Pfefferle, Lisa D; Haller, Gary L

2012-10-16T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

Molecular water oxidation catalyst  

DOE Patents (OSTI)

A dimeric composition of the formula: ##STR1## wherein L', L", L'", and L"" are each a bidentate ligand having at least one functional substituent, the ligand selected from bipyridine, phenanthroline, 2-phenylpyridine, bipyrimidine, and bipyrazyl and the functional substituent selected from carboxylic acid, ester, amide, halogenide, anhydride, acyl ketone, alkyl ketone, acid chloride, sulfonic acid, phosphonic acid, and nitro and nitroso groups. An electrochemical oxidation process for the production of the above functionally substituted bidentate ligand diaqua oxo-bridged ruthenium dimers and their use as water oxidation catalysts is described.

Gratzel, Michael (St. Sulpice, CH); Munavalli, Shekhar (Bel Air, MD); Pern, Fu-Jann (Lakewood, CO); Frank, Arthur J. (Lakewood, CO)

1993-01-01T23:59:59.000Z

402

Alternative catalyst and exhaust gas sensor work at Argonne National Laboratory  

DOE Green Energy (OSTI)

Research programs at Argonne National Laboratory in the areas of automobile emissions monitoring and control are described. The mandate to improve automobile efficiency while reducing Pollution requires the development of new catalysts for exhaust emissions control that are capable of functioning efficiently under lean-burn engine operating conditions. It is also desirable that the use of expensive noble metal catalysts be avoided. NO{sub x} emissions will not be efficiently controlled by the current three-way, supported noble metal catalysts under lean-burn conditions. New catalysts are being sought that could effect the selective catalytic reduction (SCR) of NO{sub x} by exhaust hydrocarbons in the presence of oxygen. Molecular sieve zeolites of the ZSM-5 and ferrierite types, ion-exchanged with copper ions, are the best of the catalysts known to effect this chemistry, but the mechanism of the SCR is still not understood. In this project the authors will first undertake the investigation of the SCR of NO using model reactions to test postulated mechanistic pathways. Initial experiments have been devised to investigate the possible participation of metal alkyl complexes, metal oxime complexes, N-alkyl-N-nitroso-alkylaminato-metal complexes, and metal nitrile complexes in the zeolites. ANL will also develop microsensors, based on surface acoustic wave (SAW) chemical sensing techniques, and a micro mass-spectrometer (MS) for tailpipe or engine-out emission monitoring. The sensor configurations and sensing techniques of the proposed SAW and micro-MS are described.

Iton, L.E.; Maroni, V.A.; Dieckman, S.L.; Sheen, S.H.; Raptis, A.C.

1994-12-31T23:59:59.000Z

403

Method for dispersing catalyst onto particulate material and product thereof  

DOE Patents (OSTI)

A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal.

Utz, Bruce R. (Pittsburgh, PA); Cugini, Anthony V. (Pittsburgh, PA)

1992-01-01T23:59:59.000Z

404

Focussing the view on Nature's water-splitting catalyst  

DOE Green Energy (OSTI)

About 3 billion years ago Nature invented a catalyst that splits water with highefficiency into molecular oxygen and hydrogen equivalents (protons and electrons). This reaction is energetically driven by sun light and the active centre contains relatively cheap and abundant metals: manganese and calcium. This biological system therefore forms the paradigm for all man made attempts for direct solar fuel production and several studies are underway to determine the electronic and geometric structures of this catalyst. In this report we briefly summarize the problems and the current status of these efforts, and propose a DFT-based strategy for obtaining a reliable high resolution structure of this unique catalyst that includes both the inorganic core and the first ligand sphere.

Messinger, Johannes; Yano, Junko

2008-01-01T23:59:59.000Z

405

Hydrogen Oxidation and Evolution Reaction Kinetics on Platinum: Acid vs Alkaline Electrolytes  

E-Print Network (OSTI)

The kinetics of the hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) on polycrystalline platinum [Pt(pc)] and high surface area carbon-supported platinum nanoparticles (Pt/C) were studied in 0.1 M ...

Sheng, Wenchao

406

Comparison of platinum deposit methods on carbon aerogels used in Proton Exchange Membrane Fuel Cells (PEMFC)  

E-Print Network (OSTI)

Comparison of platinum deposit methods on carbon aerogels used in Proton Exchange Membrane Fuel: carbon aerogel, platinum, Strong Electrostatic Adsorption, chemical reduction, UV With the rarefaction the diffusive phenomena limiting electrochemical performances. By contrast, carbon aerogels present

Paris-Sud XI, Université de

407

Water Uptake in PEMFC Catalyst Layers  

NLE Websites -- All DOE Office Websites (Extended Search)

Water Uptake in PEMFC Catalyst Layers Title Water Uptake in PEMFC Catalyst Layers Publication Type Journal Article LBNL Report Number LBNL-5322E Year of Publication 2011 Authors...

408

Electrocatalyst for Oxygen Reduction with Reduced Platinum Oxidation and Dissolution Rates  

Platinum is the most efficient electrocatalyst for accelerating the oxygen reduction reaction in fuel cells. Under operating conditions, though, ...

409

PLATINUM HEXAFLUORIDE AND METHOD OF FLUORINATING PLUTONIUM CONTAINING MIXTURES THERE-WITH  

DOE Patents (OSTI)

The preparation of platinum hexafluoride and its use as a fluorinating agent in a process for separating plutonium from fission products is presented. According to the invention, platinum is reacted with fluorine gas at from 900 to 1100 deg C to form platinum hexafluoride. The platinum hexafluoride is then contacted with the plutonium containing mixture at room temperature to form plutonium hexafluoride which is more volatile than the fission products fluorides and therefore can be isolated by distillation.

Malm, J.G.; Weinstock, B.; Claassen, H.H.

1959-07-01T23:59:59.000Z

410

Materials - Catalysts for Diesel Engines  

NLE Websites -- All DOE Office Websites (Extended Search)

Argonne's deNOx Catalyst Begins Extensive Diesel Engine Exhaust Testing Argonne's deNOx Catalyst Begins Extensive Diesel Engine Exhaust Testing denox monolith Argonne's deNOx catalyst can be prepared as a powder or a monolith. chris marshall Principal investigator Chris Marshall shows the monolith form of the Argonne deNOx catalyst with a sensor inserted for testing. doug longman Mechanical engineer Doug Longman inserts the instrumented deNOx catalyst monolith into the aftertreatment chamber of Argonne's heavy-duty Caterpillar diesel test engine. Background Diesel engines, while efficient, produce many undesirable combustion byproducts in their exhaust. While we tend to think of the sooty exhaust products we see as the bad stuff, it is the less-visible exhaust products such as nitrogen oxides (NOx) that create bigger problems.

411

Microemulsion impregnated catalyst composite and use thereof in a synthesis gas conversion process  

DOE Patents (OSTI)

A catalyst composition for synthesis gas conversion comprising a ruthenium metal component deposited on a support carrier wherein the average metal particle size is less than about 100 A. The method of manufacture of the composition via a reverse micelle impregnation technique and the use of the composition in a Fischer-Tropsch conversion process is also disclosed.

Abrevaya, Hayim (Chicago, IL); Targos, William M. (Palatine, IL)

1987-01-01T23:59:59.000Z

412

Microemulsion impregnated catalyst composite and use thereof in a synthesis gas conversion process  

DOE Patents (OSTI)

A catalyst composition is described for synthesis gas conversion comprising a ruthenium metal component deposited on a support carrier wherein the average metal particle size is less than about 100 A. The method of manufacture of the composition via a reverse micelle impregnation technique and the use of the composition in a Fischer-Tropsch conversion process is also disclosed.

Abrevaya, H.; Targos, W.M.

1987-12-22T23:59:59.000Z

413

Amphiphilic Phase-transforming Catalysts for Transesterification of Triglycerides  

E-Print Network (OSTI)

Heterogeneous catalytic reactions that involve immiscible liquid-phase reactants are challenging to conduct due to limitations associated with mass transport. Nevertheless, there are numerous reactions such as esterification, transesterification, etherification, and hydrolysis where two immiscible liquid reactants (such as polar and non-polar liquids) need to be brought into contact with a catalyst. With the intention of alleviating mass transport issues associated with such systems but affording the ability to separate the catalyst once the reaction is complete, the overall goal of this study is geared toward developing a catalyst that has emulsification properties as well as the ability to phase-transfer (from liquid-phase to solid-phase) while the reaction is ongoing and evaluating the effectiveness of such a catalytic process in a practical reaction. To elucidate this concept, the transesterification reaction was selected. Metal-alkoxides that possess acidic and basic properties (to catalyze the reaction), amphiphilic properties (to stabilize the alcohol/oil emulsion) and that can undergo condensation polymerization when heated (to separate as a solid subsequent to the completion of the reaction) were used to test the concept. Studies included elucidating the effect of metal sites and alkoxide sites and their concentration effects on transesterification reaction, effect of various metal alkoxide groups on the phase stability of the reactant system, and kinetic effects of the reaction system. The studies revealed that several transition-metal alkoxides, especially, titanium and yttrium based, responded positively to this reaction system. These alkoxides were able to be added to the reaction medium in liquid phase and were able to stabilize the alcohol/oil system. The alkoxides were selective to the transesterification reaction giving a range of ester yields (depending on the catalyst used). It was also observed that transition-metal alkoxides were able to be recovered in the form of their polymerized counterparts as a result of condensation polymerization subsequent to completion of the transesterification reaction.

Nawaratna, Gayan I

2013-05-01T23:59:59.000Z

414

Fernald Preserve Visitors Center Grand Opening and LEED Platinum  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Fernald Preserve Visitors Center Grand Opening and LEED Platinum Fernald Preserve Visitors Center Grand Opening and LEED Platinum Certification Fernald Preserve Visitors Center Grand Opening and LEED Platinum Certification October 16, 2008 - 4:14pm Addthis Remarks as Prepared for Acting Deputy Secretary Kupfer Thank you, Mike, for that introduction and to both you and Jane for hosting this event. You both have been instrumental in the dramatic transformation of this site. We made a commitment more than a decade ago to do three things here at Fernald: to close it, to clean it up and to give it back to the community. I'm proud to say we have fulfilled that commitment safely and ahead of schedule. Less than two years ago, I was here with Secretary Bodman as he announced the completion of a $4.4 billion clean up operation. Since then, we have

415

Fernald Preserve Visitors Center Grand Opening and LEED Platinum  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Fernald Preserve Visitors Center Grand Opening and LEED Platinum Fernald Preserve Visitors Center Grand Opening and LEED Platinum Certification Fernald Preserve Visitors Center Grand Opening and LEED Platinum Certification October 16, 2008 - 4:14pm Addthis Remarks as Prepared for Acting Deputy Secretary Kupfer Thank you, Mike, for that introduction and to both you and Jane for hosting this event. You both have been instrumental in the dramatic transformation of this site. We made a commitment more than a decade ago to do three things here at Fernald: to close it, to clean it up and to give it back to the community. I'm proud to say we have fulfilled that commitment safely and ahead of schedule. Less than two years ago, I was here with Secretary Bodman as he announced the completion of a $4.4 billion clean up operation. Since then, we have

416

Appendix: Platinum Availability and Economics for PEMFC Commercialization  

NLE Websites -- All DOE Office Websites (Extended Search)

D0034.2004-01-06 PGM Final Report.ppt D0034.2004-01-06 PGM Final Report.ppt Table of Contents Project Overview 3 4 5 Econometric Modeling 2 Platinum Market Overview 6 6 1 Executive Summary Future Demand Scenarios 2005-2050 Appendix Appendix 1 D0034.2004-01-06 PGM Final Report.ppt Appendix Appendix Summary of Previous Studies Econometric Analyses Vehicle Forecasts Stationary Fuel Cell Markets Platinum Mining 2 D0034.2004-01-06 PGM Final Report.ppt Appendix Previous Studies Introduction Several studies have modeled fuel cell vehicle market penetration and its effect on platinum availability. 19 g Pt 22 g Pt Low - 5 g Pt Study g Pt per FCV FCV Market Penetration 100% penetration in 2100 (global) 400 million FCV annual production Best case: 100% in 2070 (US fleet growth = 25.3 million FCV/year in 2050) RÃ¥de Doctoral Thesis

417

EFFECT OF PRETREATMENT ON PT-CO/C CATHODE CATALYSTS FOR THE OXYGEN-REDUCTION REACTION  

DOE Green Energy (OSTI)

Carbon supported Pt and Pt-Co electrocatalysts for the oxygen reduction reaction in low temperature fuel cells were prepared by the reduction of the metal salts with sodium borohydride and sodium formate. The effect of surface treatment with nitric acid on the carbon surface and Co on the surface of carbon prior to the deposition of Pt was studied. The catalysts where Pt was deposited on treated carbon the ORR reaction preceded more through the two electron pathway and favored peroxide production, while the fresh carbon catalysts proceeded more through the four electron pathway to complete the oxygen reduction reaction. NaCOOH reduced Pt/C catalysts showed higher activity that NaBH{sub 4} reduced Pt/C catalysts. It was determined that the Co addition has a higher impact on catalyst activity and active surface area when used with NaBH{sub 4} as reducing agent as compared to NaCOOH.

Fox, E.; Colon-Mercado, H.

2010-01-19T23:59:59.000Z

418

Investigation of sulfur-tolerant catalysts for selective synthesis of hydrocarbon liquids from coal-derived gases. Quarterly technical progress report, March 19-June 18, 1980  

DOE Green Energy (OSTI)

A 15% Fe-3% K/sub 2/O on SiO/sub 2/ catalyst, a 15% Co-3% K/sub 2/O on SiO catalyst and a 15% CoB/SiO/sub 2/ catalyst were prepared. H/sub 2/ and CO chemisorption uptakes were measured for the catalysts prepared to date. It was noted that calcining the iron catalysts in air before reduction in flowing H/sub 2/ aided in increasing metal dispersion. Liquid and wax traps for use in the reactor system were completed as were plans for chromatographic product analysis.

Bartholomew, C H

1980-07-10T23:59:59.000Z

419

Poster CATALYST SULPHUR ADDITIVES IN THE GROWTH OF CARBON NANOTUBES  

E-Print Network (OSTI)

Scientific community have recently focused especial attention on carbon nanomaterials, specially on carbon nanotubes (CNTs), because of their fascinating physical properties and potential applications [1]. Some of these applications, such as gas and energy storage, require high yields of well-defined qualities, what makes Chemical Vapor Deposition (CVD) one of the most appropriate methods for the synthesis of carbon nanotubes as it is easily scalable and makes the synthesis economically available. CVD is a versatile and promising method for CNTs synthesis as it offers the possibility of controlling a high yield synthesis of carbon nanotubes (CNTs) with specific properties by only controlling the different parameters taking place in the furnace during the hydrocarbon feedstock decomposition over a metal catalyst [2]. This communication explores the growth of CNTs by chemical vapor deposition (CVD) from methane decomposition over different catalysts prepared by the sol-gel technique, using MgO as support [3, 4] and varying the transition metal (active element in the catalyst). The aim of this work is to study the influence of additives, especially sulphur in different forms, on the activity of this kind of supported catalysts and how do the yield, morphology and physical

C. Vallés; M. Pérez-mendoza; G. Legac; W. K. Maser; M. T. Martínez; A. M. Benito

2005-01-01T23:59:59.000Z

420

Approach to recover strategic metals from brines  

DOE Green Energy (OSTI)

The objective of the proposed research is to evaluate hypersaline brines from geothermal sources and salt domes as possible sources for some strategic metals. This research is suggested because several previous analyses of brine from geothermal wells in the Imperial Valley, California, and from Gulf Coast salt domes, indicate near commercial values for platinum as well as other metals (i.e., gold, silver). Extraction of the platinum should be technically feasible. A research program should include more complete systematic sampling and analysis for resource delineation, followed by bench-scale investigation of several potential extraction processes. This could be followed by engineering feasibility and design studies, for extraction of the metals either as a by-product of other operations or in a stand-alone process.

Raber, E.; Harrar, J.; Gregg, D.

1981-09-16T23:59:59.000Z

Note: This page contains sample records for the topic "metal catalysts platinum" 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

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

SciTech Connect

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

422

Chemical interactions in multimetal/zeolite catalysts  

SciTech Connect

This report treats four subject areas: PtCu/NaY and Pd/Cu/NaY catalysts; reducibility of Ni in PdNi/NaY catalysts; CO hydrogenation over PdNi/NaY catalysts; and PdFe/NaY, Ga/H-ZSM5 and PtGa/H-ZSM5 catalysts.

Sachtler, W.M.H.

1992-02-07T23:59:59.000Z

423

Structural sensitivity studies of ethylene hydrogenation on platinum and rhodium surfaces  

DOE Green Energy (OSTI)

The catalytic hydrogenation of ethylene and hydrogen on the well characterized surfaces of the noble metals platinum and rhodium has been studied for the purposes of determining the relative activity of these two substrates as well as the degree of structure sensitivity. The Pt(111) and the Rh(755) single crystal surfaces,as well as Pt and Rh foils, were employed as substrates to study the effect of surface step structure on reactivity. In addition, vibrational spectroscopy studies were performed for ethylene adsorption on the stepped Rh(755) surface. The catalytic reaction were obtained using a combined ultrahigh vacuum chamber coupled with an atmospheric pressure reaction chamber that functioned as a batch reactor. Samples could be prepared using standard surface science techniques and characterized for surface composition and geometry using Auger Electron Spectroscopy and Low Energy Electron Diffraction. A comparison of the reactivity of Rh(111) with the results from this study on Rh(755) allows a direct determination of the effect of step structure on ethylene hydrogenation activity. Structure sensitivity is expected to exhibit orders of magnitude differences in rate as surface orientation is varied. In this case, no significant differences were found, confirming the structure insensitivity of this reaction over this metal. The turnover frequency of the Rh(111) surface, 5 {times} 10{sup 1} s{sup {minus}1}, is in relatively good agreement with the turnover frequency of 9 {times} 10{sup 1} s{sup {minus}1} measured for the Rh(755) surface. Rate measurements made on the Pt(111) surface and the Pt foil are in excellent agreement, both measuring 3 {times} 10{sup 2} s{sup minus}1. Likewise, it is concluded that no strong structure sensitivity for the platinum surfaces exists. High Resolution Electron Energy Loss Spectroscopy studies of adsorbed ethylene on the Rh(755) surface compare favorably with the ethylidyne spectra obtained on the Rh(111) and Rh(100) surfaces.

Quinlan, M.A. [California Univ., Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley National Lab., CA (United States)

1996-01-01T23:59:59.000Z

424

Heterogeneous catalyst for the production of ethylidene diacetate from acetic anhydride  

DOE Patents (OSTI)

This invention relates to a process for producing ethylidene diacetate by the reaction of acetic anhydride, acetic acid, hydrogen and carbon monoxide at elevated temperatures and pressures in the presence of an alkyl halide and a heterogeneous, bifunctional catalyst that is stable to hydrogenation and comprises an insoluble polymer having pendant quaternized heteroatoms, some of which heteroatoms are ionically bonded to anionic Group VIII metal complexes, the remainder of the heteroatoms being bonded to iodide. In contrast to prior art processes, no accelerator (promoter) is necessary to achieve the catalytic reaction and the products are easily separated from the catalyst by filtration. The catalyst can be recycled without loss in activity.

Ramprasad, D.; Waller, F.J.

1998-06-16T23:59:59.000Z

425

Heterogeneous catalyst for the production of ethylidene diacetate from acetic anhydride  

DOE Patents (OSTI)

This invention relates to a process for producing ethylidene diacetate by the reaction of acetic anhydride, acetic acid, hydrogen and carbon monoxide at elevated temperatures and pressures in the presence of an alkyl halide and a heterogeneous, bifunctional catalyst that is stable to hydrogenation and comprises an insoluble polymer having pendant quaternized heteroatoms, some of which heteroatoms are ionically bonded to anionic Group VIII metal complexes, the remainder of the heteroatoms being bonded to iodide. In contrast to prior art processes, no accelerator (promoter) is necessary to achieve the catalytic reaction and the products are easily separated from the catalyst by filtration. The catalyst can be recycled without loss in activity.

Ramprasad, Dorai (Allentown, PA); Waller, Francis Joseph (Allentown, PA)

1998-01-01T23:59:59.000Z

426

Method for generating a highly reactive plasma for exhaust gas aftertreatment and enhanced catalyst reactivity  

DOE Patents (OSTI)

A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime, high frequency, high power bursts of low-duty factor microwaves sufficient to generate a plasma discharge and passing a gas to be treated through the discharge so as to cause dissociative reduction of the exhaust gases and enhanced catalyst reactivity through application of the pulsed microwave fields directly to the catalyst material sufficient to cause a polarizability catastrophe and enhanced heating of the metal crystallite particles of the catalyst, and in the presence or absence of the plasma. The invention also includes a reactor for aftertreatment of exhaust gases.

Whealton, John H. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Storey, John M. (Oak Ridge, TN); Raridon, Richard J. (Oak Ridge, TN); Armfield, Jeffrey S. (Ypsilanti, MI); Bigelow, Timothy S. (Knoxville, TN); Graves, Ronald L. (Knoxville, TN)

2002-01-01T23:59:59.000Z

427

COMPARISON OF PLASMA-CATALYST AND ACTIVE LEAN NOx CATALYST  

DOE Green Energy (OSTI)

A number of NO{sub x} control systems are being discussed for potential application to diesel engines. Unfortunately, it can be difficult to compare systems on an equal basis because data are run under different conditions, or reported against different test cycles, or not shown over a range of operating conditions. In addition, the fuel consumption penalty associated with the NO{sub x} control technologies is not always reported. In this paper, we compare two diesel NO{sub x} aftertreatment systems: (1) Plasma-Catalyst (PC): a nonthermal plasma followed by a catalyst; and (2) Active Lean NO{sub x} Catalyst (ALNC): a NO{sub x} catalyst designed to selectively reduce NO{sub x} using hydrocarbon (HC) in the form of diesel fuel. Fuel is added to the exhaust to increase HC above normal diesel levels. These systems will be described in more detail in this report.

Hoard, John

2000-08-20T23:59:59.000Z

428

High Temperature Membrane & Advanced Cathode Catalyst Development  

DOE Green Energy (OSTI)

Current project consisted of three main phases and eighteen milestones. Short description of each phase is given below. Table 1 lists program milestones. Phase 1--High Temperature Membrane and Advanced Catalyst Development. New polymers and advanced cathode catalysts were synthesized. The membranes and the catalysts were characterized and compared against specifications that are based on DOE program requirements. The best-in-class membranes and catalysts were downselected for phase 2. Phase 2--Catalyst Coated Membrane (CCM) Fabrication and Testing. Laboratory scale catalyst coated membranes (CCMs) were fabricated and tested using the down-selected membranes and catalysts. The catalysts and high temperature membrane CCMs were tested and optimized. Phase 3--Multi-cell stack fabrication. Full-size CCMs with the down-selected and optimized high temperature membrane and catalyst were fabricated. The catalyst membrane assemblies were tested in full size cells and multi-cell stack.

Protsailo, Lesia

2006-04-20T23:59:59.000Z

429

Shape-selective catalysts for Fischer-Tropsch chemistry : iron-containing particulate catalysts. Activity report : January 1, 2001 - December 31, 2004.  

DOE Green Energy (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. It is desired that selectivity be directed toward producing diesel fraction components and avoiding excess yields of both light hydrocarbons and heavy waxes. The goal is to produce shape-selective catalysts that have the potential to limit the formation of longchain products and yet retain the active metal sites in a protected 'cage'. This cage also restricts their loss by attrition during use in slurry-bed reactors. The first stage of this program was to prepare and evaluate iron-containing particulate catalysts. This activity report centers upon this first stage of experimentation with particulate FT catalysts. (For reference, a second experimental stage is under way to prepare and evaluate active FT catalysts formed by atomic-layer deposition [ALD] of active components on supported membranes.) To date, experimentation has centered upon the evaluation of a sample of iron-based, spray-dried catalyst prepared by B.H. Davis of the Center of Applied Energy Research (CAER) and samples of his catalyst onto which inorganic 'shells' were deposited. The reference CAER catalyst contained a high level of dispersed fine particles, a portion of which was removed by differential settling. Reaction conditions have been established using a FT laboratory unit such that reasonable levels of CO conversion can be achieved, where therefore a valid catalyst comparison can be made. A wide range of catalytic activities was observed with SiO{sub 2}-coated FT catalysts. Two techniques were used for SiO{sub 2}coating. The first involved a caustic precipitation of SiO{sub 2} from an organo-silicate onto the CAER catalyst. The second was the acidic precipitation of an organo-silicate with aging to form fractal particles that were then deposited onto the CAER catalyst. Several resulting FT catalysts were as active as the coarse catalyst on which they were prepared. The most active ones were those with the least amount of coating, namely about 2.2 wt% SiO{sub 2}. In the case of the latter acid technique, the use of HCl and HNO{sub 3} was much more effective than that of H{sub 2}SO{sub 4}. Scanning electron microscopy (SEM) was used to observe and analyze as-received and treated FT catalysts. It was observed that (1) spherical particles of CAER FT catalyst were made up of agglomerates of particles that were, in turn, also agglomerates; (2) the spray drying process of CAER apparently concentrated the Si precursor at the surface during drying; (3) while SEM pointed out broad differences in the appearance of the prepared catalyst particles, there was little indication that the catalysts were being uniformly coated with a cage-like protective surface, with perhaps the exception of HNO{sub 3}-precipitated catalyst; and (4) there was only a limited penetration of carbon (i.e., CO) into the FT catalyst during the conditioning and FT reaction steps.

Cronauer, D.; Chemical Engineering

2006-05-12T23:59:59.000Z

430

Technology development for iron F-T catalysts. Final report  

DOE Green Energy (OSTI)

The objectives of this work were twofold. The first objective was to design and construct a pilot plant for preparing precipitated iron oxide F-T precursors and demonstrate that the rate of production from this plant is equivalent to 100 lbs/day of dried metal oxide. Secondly, these precipitates were to be used to prepare catalysts capable of achieving 88% CO + H{sub 2} conversion with {le} 5 mole percent selectivity to methane + ethane.

Frame, R.R.; Gala, H.B.

1994-08-01T23:59:59.000Z

431

Mercury and platinum abundances in mercury-manganese stars  

E-Print Network (OSTI)

We report new results for the elemental and isotopic abundances of the normally rare elements mercury and platinum in HgMn stars. Typical overabundances can be 4 dex or more. The isotopic patterns do not follow the fractionation model of White et al (1976).

C. M. Jomaron; M. M. Dworetsky; D. A. Bohlender

1998-05-06T23:59:59.000Z

432

Necessary conditions on entanglement catalysts  

E-Print Network (OSTI)

Given a pure state transformation $\\psi\\mapsto\\phi$ restricted to entanglement-assisted local operations with classical communication, we determine a lower bound for the dimension of a catalyst allowing that transformation. Our bound is stated in terms of the generalised concurrence monotones (the usual concurrence of two qubits is one such monotone). We further provide tools for deriving further conditions upon catalysts of pure state transformations.

Sanders, Yuval

2009-01-01T23:59:59.000Z

433

Necessary conditions on entanglement catalysts  

E-Print Network (OSTI)

Given a pure state transformation $\\psi\\mapsto\\phi$ restricted to entanglement-assisted local operations with classical communication, we determine a lower bound for the dimension of a catalyst allowing that transformation. Our bound is stated in terms of the generalised concurrence monotones (the usual concurrence of two qubits is one such monotone). We further provide tools for deriving further conditions upon catalysts of pure state transformations.

Yuval Sanders; Gilad Gour

2009-04-14T23:59:59.000Z

434

Hydrothermal alkali metal recovery process  

DOE Patents (OSTI)

In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered from the particles by treating them with a calcium or magnesium-containing compound in the presence of water at a temperature between about 250.degree. F. and about 700.degree. F. and in the presence of an added base to establish a pH during the treatment step that is higher than would otherwise be possible without the addition of the base. During the treating process the relatively high pH facilitates the conversion of water-insoluble alkali metal compounds in the alkali metal residues into water-soluble alkali metal constituents. The resultant aqueous solution containing water-soluble alkali metal constituents is then separated from the residue solids, which consist of the treated particles and any insoluble materials formed during the treatment step, and recycled to the gasification process where the alkali metal constituents serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst. Preferably, the base that is added during the treatment step is an alkali metal hydroxide obtained by water washing the residue solids produced during the treatment step.

Wolfs, Denise Y. (Houston, TX); Clavenna, Le Roy R. (Baytown, TX); Eakman, James M. (Houston, TX); Kalina, Theodore (Morris Plains, NJ)

1980-01-01T23:59:59.000Z

435

Hydrothermal alkali metal recovery process  

SciTech Connect

In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered from the particles by treating them with a calcium or magnesium-containing compound in the presence of water at a temperature between about 250/sup 0/F and about 700/sup 0/F and in the presence of an added base to establish a pH during the treatment step that is higher than would otherwise be possible without the addition of the base. During the treating process the relatively high pH facilitates the conversion of water-insoluble alkali metal compounds in the alkali metal residues into water-soluble alkali metal constituents. The resultant aqueous solution containing watersoluble alkali metal constituents is then separated from the residue solids, which consist of the treated particles and any insoluble materials formed during the treatment step, and recycled to the gasification process where the alkali metal constituents serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst. Preferably, the base that is added during the treatment step is an alkali metal hydroxide obtained by water washing the residue solids produced during the treatment step.

Clavenna, L.R.; Eakman, J.M.; Kalina, T.; Wolfs, D.Y.

1980-08-26T23:59:59.000Z

436

Creating a culture of assessment: A catalyst for organizational change  

E-Print Network (OSTI)

Culture of Assessment: A Catalyst for Organizational ChangeCulture of Assessment: A Catalyst for Organizational ChangeCulture of Assessment: A Catalyst for Organizational Change

Lakos, Amos; Phipps, Shelley

2004-01-01T23:59:59.000Z

437

Catalyst-infiltrated supporting cathode for thin-film SOFCs  

E-Print Network (OSTI)

LBNL-55226 Catalyst-Infiltrated Supporting Cathode for Thin-demonstrate that cobalt catalyst-infiltrated LSM can beinfiltrating nano- sized catalyst particles into its pores

Yamahara, Keiji; Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

2004-01-01T23:59:59.000Z

438

Studies of Various Hydrocarbon Conversion Reactions on Pt Catalysts  

E-Print Network (OSTI)

observed after reduction on tetrahedral and cubic catalysts.Prepared catalysts………..…….……………………. ………………..……..35reactions on shape controlled catalysts………………………………22 3.1.

Kaneko, Shinji

2011-01-01T23:59:59.000Z

439

Business Case Slide 22: High-Value: Catalysts - Description  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalysts - Description Graduate student examining candidate DU-bearing catalyst Graduate student examining candidate DU-bearing catalyst Description Use DUO2 to catalyze chemical...

440

Business Case Slide 24: High-Value: Catalysts - Program Focus  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalysts - Program Focus Program Focus Off-gas cleanup catalysts (ORNL) Best form and substrate, effect of impurities Desulfurization catalyst (Rutgers) Proof-of-principle...

Note: This page contains sample records for the topic "metal catalysts platinum" from the National Library of EnergyBeta (NLEBeta).
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