National Library of Energy BETA

Sample records for dilute sulfuric acid

  1. Sulfuric acid-sulfur heat storage cycle

    DOE Patents [OSTI]

    Norman, John H.

    1983-12-20

    A method of storing heat is provided utilizing a chemical cycle which interconverts sulfuric acid and sulfur. The method can be used to levelize the energy obtained from intermittent heat sources, such as solar collectors. Dilute sulfuric acid is concentrated by evaporation of water, and the concentrated sulfuric acid is boiled and decomposed using intense heat from the heat source, forming sulfur dioxide and oxygen. The sulfur dioxide is reacted with water in a disproportionation reaction yielding dilute sulfuric acid, which is recycled, and elemental sulfur. The sulfur has substantial potential chemical energy and represents the storage of a significant portion of the energy obtained from the heat source. The sulfur is burned whenever required to release the stored energy. A particularly advantageous use of the heat storage method is in conjunction with a solar-powered facility which uses the Bunsen reaction in a water-splitting process. The energy storage method is used to levelize the availability of solar energy while some of the sulfur dioxide produced in the heat storage reactions is converted to sulfuric acid in the Bunsen reaction.

  2. Corrosion resistance and behavior of construction materials exposed to dilute sulfuric acid at elevated temperatures under static conditions

    SciTech Connect (OSTI)

    Nguyen, D.T.

    1994-10-01

    Laboratory investigation has been undertaken to determine the electrochemical behavior and corrosion resistance of various construction materials in a simulated hydrolysis environment (5 wt % sulfuric acid) at temperatures ranging from 90 to 220C. Tests were performed in an autoclave-type electrochemical cell. The corrosion behavior of the test materials was determined using computer-controlled DC potentiodynamic polarization. Corrosion rates of the test materials were determined using AC impedance techniques. Among the stainless steels tested, only alloy N08026 (Carpenter 20Mo-6) performed satisfactory up to a temperature of 100C. The alloy passivated spontaneously in the environment and corroded at a rate of less than 2 mpy. None of the stainless steels tested could be used at 120{degrees}C or above. A number of nickel-based alloys tested had good corrosion resistance up to 100C, but their corrosion rate exceeded 2 mpy at higher temperatures. Zirconium alloys were satisfactory up to 180C. Only tantalum and a tantalum-niobium alloy were satisfactory up to 220C.

  3. Process for forming sulfuric acid

    DOE Patents [OSTI]

    Lu, Wen-Tong P.

    1981-01-01

    An improved electrode is disclosed for the anode in a sulfur cycle hydrogen generation process where sulfur dioxie is oxidized to form sulfuric acid at the anode. The active compound in the electrode is palladium, palladium oxide, an alloy of palladium, or a mixture thereof. The active compound may be deposited on a porous, stable, conductive substrate.

  4. Martinez Sulfuric Acid Regeneration Plt Biomass Facility | Open...

    Open Energy Info (EERE)

    Martinez Sulfuric Acid Regeneration Plt Biomass Facility Jump to: navigation, search Name Martinez Sulfuric Acid Regeneration Plt Biomass Facility Facility Martinez Sulfuric Acid...

  5. Dilute acid/metal salt hydrolysis of lignocellulosics

    DOE Patents [OSTI]

    Nguyen, Quang A.; Tucker, Melvin P.

    2002-01-01

    A modified dilute acid method of hydrolyzing the cellulose and hemicellulose in lignocellulosic material under conditions to obtain higher overall fermentable sugar yields than is obtainable using dilute acid alone, comprising: impregnating a lignocellulosic feedstock with a mixture of an amount of aqueous solution of a dilute acid catalyst and a metal salt catalyst sufficient to provide higher overall fermentable sugar yields than is obtainable when hydrolyzing with dilute acid alone; loading the impregnated lignocellulosic feedstock into a reactor and heating for a sufficient period of time to hydrolyze substantially all of the hemicellulose and greater than 45% of the cellulose to water soluble sugars; and recovering the water soluble sugars.

  6. Two-stage dilute acid prehydrolysis of biomass

    DOE Patents [OSTI]

    Grohmann, Karel; Torget, Robert W.

    1992-01-01

    A two-stage dilute acid prehydrolysis process on xylan containing hemicellulose in biomass is effected by: treating feedstock of hemicellulosic material comprising xylan that is slow hydrolyzable and xylan that is fast hydrolyzable under predetermined low temperature conditions with a dilute acid for a residence time sufficient to hydrolyze the fast hydrolyzable xylan to xylose; removing said xylose from said fast hydrolyzable xylan and leaving a residue; and treating said residue having a slow hydrolyzable xylan with a dilute acid under predetermined high temperature conditions for a residence time required to hydrolyze said slow hydrolyzable xylan to xylose.

  7. Sulfuric acid thermoelectrochemical system and method

    DOE Patents [OSTI]

    Ludwig, Frank A.

    1989-01-01

    A thermoelectrochemical system in which an electrical current is generated between a cathode immersed in a concentrated sulfuric acid solution and an anode immersed in an aqueous buffer solution of sodium bisulfate and sodium sulfate. Reactants consumed at the electrodes during the electrochemical reaction are thermochemically regenerated and recycled to the electrodes to provide continuous operation of the system.

  8. Ethanol production with dilute acid hydrolysis using partially dried lignocellulosics

    DOE Patents [OSTI]

    Nguyen, Quang A.; Keller, Fred A.; Tucker, Melvin P.

    2003-12-09

    A process of converting lignocellulosic biomass to ethanol, comprising hydrolyzing lignocellulosic materials by subjecting dried lignocellulosic material in a reactor to a catalyst comprised of a dilute solution of a strong acid and a metal salt to lower the activation energy (i.e., the temperature) of cellulose hydrolysis and ultimately obtain higher sugar yields.

  9. Characterization of Lignin Derived from Water-only and Dilute Acid Flowthrough Pretreatment of Poplar Wood at Elevated Temperatures

    SciTech Connect (OSTI)

    Zhang, Libing; Yan, Lishi; Wang, Zheming; Laskar, Dhrubojyoti D.; Swita, Marie S.; Cort, John R.; Yang, Bin

    2015-12-01

    Background: Flowthrough pretreatment of biomass has high potential to valorize lignin derivatives to high-value products, which is vital to enhance the economy of biorefinery plants. Comprehensive understanding of lignin behaviors and solubilization chemistry in aqueous pretreatment such as water-only and dilute acid flowthrough pretreatment is of fundamental importance to achieve the goal of providing flexible platform for lignin utilization. Results: In this study, the effects of flowthrough pretreatment conditions on lignin separation from poplar wood were reported as well as the characteristics of three sub-sets of lignin produced from the pretreatment, including residual lignin in pretreated solid residues (ReL), recovered insoluble lignin in pretreated liquid (RISL), and recovered soluble lignin in pretreatment liquid (RSL). Both the water-only and 0.05% (w/w) sulfuric acid pretreatments were performed at temperatures from 160 to 270°C on poplar wood in a flowthrough reactor system for 2-10 min. Results showed that water-only flowthrough pretreatment primarily removed syringyl (S units). Increased temperature and/or the addition of sulfuric acid enhanced the removal of guaiacyl (G units) compared to water-only pretreatments at lower temperatures, resulting in nearly complete removal of lignin from the biomass. Results also suggested that more RISL was recovered than ReL and RSL in both dilute acid and water-only flowthrough pretreatment at elevated temperatures. NMR spectra of the RISL revealed significant β-O-4 cleavage, α-β deoxygenation to form cinnamyl-like end groups, and slight β-5 repolymerization in both water-only and dilute acid flowthrough pretreatments. Conclusions: Elevated temperature and/or dilute acid greatly enhanced lignin removal to almost 100% by improving G unit removal besides S unit removal in flowthrough system. A new lignin chemistry transformation pathway was proposed and revealed the complexity of lignin structural change

  10. Characterization of lignin derived from water-only and dilute acid flowthrough pretreatment of poplar wood at elevated temperatures

    SciTech Connect (OSTI)

    Zhang, Libing; Yan, Lishi; Wang, Zheming; Laskar, Dhrubojyoti D.; Swita, Marie S.; Cort, John R.; Yang, Bin

    2015-12-01

    In this study, flowthrough pretreatment of biomass has high potential to valorize lignin derivatives to high-value products, which is vital to enhance the economy of biorefinery plants. Comprehensive understanding of lignin behaviors and solubilization chemistry in aqueous pretreatment such as water-only and dilute acid flowthrough pretreatment is of fundamental importance to achieve the goal of providing flexible platform for lignin utilization. In this study, the effects of flowthrough pretreatment conditions on lignin separation from poplar wood were reported as well as the characteristics of three sub-sets of lignin produced from the pretreatment, including residual lignin in pretreated solid residues (ReL), recovered insoluble lignin in pretreated liquid (RISL), and recovered soluble lignin in pretreatment liquid (RSL). Both the water-only and 0.05% (w/w) sulfuric acid pretreatments were performed at temperatures from 160 to 270°C on poplar wood in a flowthrough reactor system for 2-10 min. Results showed that water-only flowthrough pretreatment primarily removed syringyl (S units). Increased temperature and/or the addition of sulfuric acid enhanced the removal of guaiacyl (G units) compared to water-only pretreatments at lower temperatures, resulting in nearly complete removal of lignin from the biomass. Results also suggested that more RISL was recovered than ReL and RSL in both dilute acid and water-only flowthrough pretreatment at elevated temperatures. NMR spectra of the RISL revealed significant β-O-4 cleavage, α-β deoxygenation to form cinnamyl-like end groups, and slight β-5 repolymerization in both water-only and dilute acid flowthrough pretreatments. In conclusion, elevated temperature and/or dilute acid greatly enhanced lignin removal to almost 100% by improving G unit removal besides S unit removal in flowthrough system. A new lignin chemistry transformation pathway was proposed and revealed the complexity of lignin structural change during

  11. Integrated boiler, superheater, and decomposer for sulfuric acid decomposition

    DOE Patents [OSTI]

    Moore, Robert; Pickard, Paul S.; Parma, Jr., Edward J.; Vernon, Milton E.; Gelbard, Fred; Lenard, Roger X.

    2010-01-12

    A method and apparatus, constructed of ceramics and other corrosion resistant materials, for decomposing sulfuric acid into sulfur dioxide, oxygen and water using an integrated boiler, superheater, and decomposer unit comprising a bayonet-type, dual-tube, counter-flow heat exchanger with a catalytic insert and a central baffle to increase recuperation efficiency.

  12. Characterization of lignin derived from water-only and dilute acid flowthrough pretreatment of poplar wood at elevated temperatures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Libing; Yan, Lishi; Wang, Zheming; Laskar, Dhrubojyoti D.; Swita, Marie S.; Cort, John R.; Yang, Bin

    2015-12-01

    In this study, flowthrough pretreatment of biomass has high potential to valorize lignin derivatives to high-value products, which is vital to enhance the economy of biorefinery plants. Comprehensive understanding of lignin behaviors and solubilization chemistry in aqueous pretreatment such as water-only and dilute acid flowthrough pretreatment is of fundamental importance to achieve the goal of providing flexible platform for lignin utilization. In this study, the effects of flowthrough pretreatment conditions on lignin separation from poplar wood were reported as well as the characteristics of three sub-sets of lignin produced from the pretreatment, including residual lignin in pretreated solid residues (ReL),more » recovered insoluble lignin in pretreated liquid (RISL), and recovered soluble lignin in pretreatment liquid (RSL). Both the water-only and 0.05% (w/w) sulfuric acid pretreatments were performed at temperatures from 160 to 270°C on poplar wood in a flowthrough reactor system for 2-10 min. Results showed that water-only flowthrough pretreatment primarily removed syringyl (S units). Increased temperature and/or the addition of sulfuric acid enhanced the removal of guaiacyl (G units) compared to water-only pretreatments at lower temperatures, resulting in nearly complete removal of lignin from the biomass. Results also suggested that more RISL was recovered than ReL and RSL in both dilute acid and water-only flowthrough pretreatment at elevated temperatures. NMR spectra of the RISL revealed significant β-O-4 cleavage, α-β deoxygenation to form cinnamyl-like end groups, and slight β-5 repolymerization in both water-only and dilute acid flowthrough pretreatments. In conclusion, elevated temperature and/or dilute acid greatly enhanced lignin removal to almost 100% by improving G unit removal besides S unit removal in flowthrough system. A new lignin chemistry transformation pathway was proposed and revealed the complexity of lignin structural change

  13. Effects of Fuel Dilution with Biodiesel on Lubricant Acidity...

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

    In-cylinder fuel injection to produce rich exhaust for regeneration of lean NOx trap catalyst and diesel particulate filter results in substantial fuel dilution of lubricating oil ...

  14. Breakdown of hierarchical architecture in cellulose during dilute acid pretreatments

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Yan; Inouye, Hideyo; Yang, Lin; Himmel, Michael E.; Tucker, Melvin; Makowski, Lee

    2015-02-28

    Cellulose is an attractive candidate as a feedstock for sustainable bioenergy because of its global abundance. Pretreatment of biomass has significant influence on the chemical availability of cellulose locked in recalcitrant microfibrils. Optimizing pretreatment depends on an understanding of its impact on the microscale and nanoscale molecular architecture. X-ray scattering experiments have been performed on native and pre-treated maize stover and models of cellulose architecture have been derived from these data. Ultra small-angle, very small-angle and small-angle X-ray scattering (USAXS, VSAXS and SAXS) probe three different levels of architectural scale. USAXS and SAXS have been used to study cellulose atmore » two distinct length scales, modeling the fibrils as ~30 Å diameter rods packed into ~0.14 μm diameter bundles. VSAXS is sensitive to structural features at length scales between these two extremes. Detailed analysis of diffraction patterns from untreated and pretreated maize using cylindrical Guinier plots and the derivatives of these plots reveals the presence of substructures within the ~0.14 μm diameter bundles that correspond to grouping of cellulose approximately 30 nm in diameter. These sub-structures are resilient to dilute acid pretreatments but are sensitive to pretreatment when iron sulfate is added. Lastly, these results provide evidence of the hierarchical arrangement of cellulose at three length scales and the evolution of these arrangements during pre-treatments.« less

  15. Breakdown of hierarchical architecture in cellulose during dilute acid pretreatments

    SciTech Connect (OSTI)

    Zhang, Yan; Inouye, Hideyo; Yang, Lin; Himmel, Michael E.; Tucker, Melvin; Makowski, Lee

    2015-02-28

    Cellulose is an attractive candidate as a feedstock for sustainable bioenergy because of its global abundance. Pretreatment of biomass has significant influence on the chemical availability of cellulose locked in recalcitrant microfibrils. Optimizing pretreatment depends on an understanding of its impact on the microscale and nanoscale molecular architecture. X-ray scattering experiments have been performed on native and pre-treated maize stover and models of cellulose architecture have been derived from these data. Ultra small-angle, very small-angle and small-angle X-ray scattering (USAXS, VSAXS and SAXS) probe three different levels of architectural scale. USAXS and SAXS have been used to study cellulose at two distinct length scales, modeling the fibrils as ~30 Å diameter rods packed into ~0.14 μm diameter bundles. VSAXS is sensitive to structural features at length scales between these two extremes. Detailed analysis of diffraction patterns from untreated and pretreated maize using cylindrical Guinier plots and the derivatives of these plots reveals the presence of substructures within the ~0.14 μm diameter bundles that correspond to grouping of cellulose approximately 30 nm in diameter. These sub-structures are resilient to dilute acid pretreatments but are sensitive to pretreatment when iron sulfate is added. Lastly, these results provide evidence of the hierarchical arrangement of cellulose at three length scales and the evolution of these arrangements during pre-treatments.

  16. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID CONTROL

    SciTech Connect (OSTI)

    Gary M. Blythe

    2001-11-06

    This document summarizes progress on Cooperative Agreement DE-FC26-99FT40718, Furnace Injection of Alkaline Sorbents for Sulfuric Acid Control, during the time period April 1, 2001 through September 30, 2001. The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The coincident removal of hydrochloric acid and hydrofluoric acid is also being determined, as is the removal of arsenic, a known poison for NO{sub x} selective catalytic reduction (SCR) catalysts. EPRI, the Tennessee Valley Authority (TVA), FirstEnergy Corporation, and the Dravo Lime Company are project co-funders. URS Corporation is the prime contractor. During the current period, American Electric Power (AEP) joined the project as an additional co-funder and as a provider of a host site for testing. This is the fourth reporting period for the subject Cooperative Agreement. During this period, two long-term sorbent injection tests were conducted, one on Unit 3 at FirstEnergy's Bruce Mansfield Plant (BMP) and one on Unit 1 at AEP's Gavin Station. These tests determined the effectiveness of injecting alkaline slurries into the upper furnace of the boiler as a means of controlling sulfuric acid emissions from these units. The alkaline slurries tested included commercially available magnesium hydroxide slurry (Gavin Station), and a byproduct magnesium hydroxide slurry (both Gavin Station and BMP). The tests showed that injecting either the commercial or the byproduct magnesium hydroxide slurry could achieve up to 70 to 75% sulfuric acid removal. At BMP, the overall removal was limited by the need to maintain acceptable electrostatic precipitator (ESP) particulate control performance. At Gavin Station, the overall sulfuric acid removal was limited because the furnace injected sorbent was less effective at removing SO{sub 3} formed across the SCR system installed on the unit for NO{sub x

  17. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID CONTROL

    SciTech Connect (OSTI)

    Gary M. Blythe

    2002-04-29

    This document summarizes progress on Cooperative Agreement DE-FC26-99FT40718, Furnace Injection of Alkaline Sorbents for Sulfuric Acid Control, during the time period October 1, 2001 through March 31, 2002. The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The coincident removal of hydrochloric acid and hydrofluoric acid is also being determined, as is the removal of arsenic, a known poison for NO{sub X} selective catalytic reduction (SCR) catalysts. EPRI, the Tennessee Valley Authority (TVA), FirstEnergy Corporation, American Electric Power (AEP) and the Dravo Lime Company are project co-funders. URS Corporation is the prime contractor. This is the fifth reporting period for the subject Cooperative Agreement. During the previous (fourth) period, two long-term sorbent injection tests were conducted, one on Unit 3 at FirstEnergy's Bruce Mansfield Plant (BMP) and one on Unit 1 at AEP's Gavin Plant. Those tests determined the effectiveness of injecting alkaline slurries into the upper furnace of the boiler as a means of controlling sulfuric acid emissions from these units. The alkaline slurries tested included commercially available magnesium hydroxide slurry (Gavin Plant) and a byproduct magnesium hydroxide slurry (at both Gavin and BMP). The tests showed that injecting either the commercial or the byproduct magnesium hydroxide slurry could achieve up to 70-75% overall sulfuric acid removal. At BMP, the overall removal was limited by the need to maintain acceptable electrostatic precipitator (ESP) particulate control performance. At Gavin Plant, the overall sulfuric acid removal was limited because the furnace injected sorbent was less effective at removing SO{sub 3} formed across the SCR system installed on the unit for NO{sub X} control than at removing SO{sub 3} formed in the furnace. The SO{sub 3} removal results were presented in the

  18. Effect of lignin content on changes occurring in poplar cellulose ultrastructure during dilute acid pretreatment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sun, Qining; Foston, Marcus; Meng, Xianzhi; Sawada, Daisuke; Pingali, Sai Venkatesh; O’Neill, Hugh M.; Li, Hongjia; Wyman, Charles E.; Langan, Paul; Ragauskas, Art J.; et al

    2014-10-14

    Obtaining a better understanding of the complex mechanisms occurring during lignocellulosic deconstruction is critical to the continued growth of renewable biofuel production. A key step in bioethanol production is thermochemical pretreatment to reduce plant cell wall recalcitrance for downstream processes. Previous studies of dilute acid pretreatment (DAP) have shown significant changes in cellulose ultrastructure that occur during pretreatment, but there is still a substantial knowledge gap with respect to the influence of lignin on these cellulose ultrastructural changes. This study was designed to assess how the presence of lignin influences DAP-induced changes in cellulose ultrastructure, which might ultimately have largemore » implications with respect to enzymatic deconstruction efforts. Native, untreated hybrid poplar (Populus trichocarpa x Populus deltoids) samples and a partially delignified poplar sample (facilitated by acidic sodium chlorite pulping) were separately pretreated with dilute sulfuric acid (0.10 M) at 160°C for 15 minutes and 35 minutes, respectively . Following extensive characterization, the partially delignified biomass displayed more significant changes in cellulose ultrastructure following DAP than the native untreated biomass. With respect to the native untreated poplar, delignified poplar after DAP (in which approximately 40% lignin removal occurred) experienced: increased cellulose accessibility indicated by increased Simons’ stain (orange dye) adsorption from 21.8 to 72.5 mg/g, decreased cellulose weight-average degree of polymerization (DPw) from 3087 to 294 units, and increased cellulose crystallite size from 2.9 to 4.2 nm. These changes following DAP ultimately increased enzymatic sugar yield from 10 to 80%. We conclude that, overall, the results indicate a strong influence of lignin content on cellulose ultrastructural changes occurring during DAP. With the reduction of lignin content during DAP, the enlargement of

  19. Adsorption of organic acids from dilute aqueous solution onto activated carbon

    SciTech Connect (OSTI)

    Wang, S.W.

    1980-06-01

    The radioisotope technique was used to study the removal of organic acid contaminants from dilute aqueous solutions onto activated carbon. Acetic acid, propionic acid, n-butyric acid, n-hexanoic acid and n-heptanoic acid were studied at 278, 298, and 313/sup 0/K. Three bi-solute acid mixtures (acetic and propionic acids, acetic and butanoic acids, and propionic and butanoic acids) were studied at 278 and 298/sup 0/K. Isotherms of the single-solute systems were obtained at three different temperatures in the very dilute concentration region (less than 1% by weight). These data are very important in the prediction of bi-solute equilibrium data. A Polanyi-based competitive adsorption potential theory was used to predict the bi-solute equilibrium uptakes. Average errors between calculated and experimental data ranges from 4% to 14%. It was found that the competitive adsorption potential theory gives slightly better results than the ideal adsorbed solution theory.

  20. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID CONTROL

    SciTech Connect (OSTI)

    Gary M. Blythe

    2003-10-01

    This document summarizes progress on Cooperative Agreement DE-FC26-99FT40718, Furnace Injection of Alkaline Sorbents for Sulfuric Acid Control, during the time period April 1, 2003 through September, 2003. The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The coincident removal of hydrochloric acid and hydrofluoric acid is also being determined, as is the removal of arsenic, a known poison for NO{sub x} selective catalytic reduction (SCR) catalysts. EPRI, the Tennessee Valley Authority (TVA), FirstEnergy Corporation, American Electric Power (AEP) and the Dravo Lime Company are project co-funders. URS Group is the prime contractor. This is the eighth reporting period for the subject Cooperative Agreement. During previous reporting periods, two long-term sorbent injection tests were conducted, one on Unit 3 at FirstEnergy's Bruce Mansfield Plant (BMP) and one on Unit 1 at AEP's Gavin Plant. Those tests determined the effectiveness of injecting alkaline slurries into the upper furnace of the boiler as a means of controlling sulfuric acid emissions from these units. The alkaline slurries tested included commercially available magnesium hydroxide slurry (Gavin Plant), and a byproduct magnesium hydroxide slurry (both Gavin Plant and BMP). The tests showed that injecting either the commercial or the byproduct magnesium hydroxide slurry could achieve up to 70-75% overall sulfuric acid removal. At BMP, the overall removal was limited by the need to maintain acceptable electrostatic precipitator (ESP) particulate control performance. At Gavin Plant, the overall sulfuric acid removal was limited because the furnace injected sorbent was less effective at removing SO{sub 3} formed across the SCR system installed on the unit for NO{sub x} control than at removing SO{sub 3} formed in the furnace. The SO{sub 3} removal results were presented in the semi

  1. SULFURIC ACID REMOVAL PROCESS EVALUATION: LONG-TERM RESULTS

    SciTech Connect (OSTI)

    Gary M. Blythe; Richard McMillan

    2002-07-03

    The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The project is being co-funded by the U.S. DOE National Energy Technology Laboratory, under Cooperative Agreement DE-FC26-99FT40718, along with EPRI, the American Electric Power Company (AEP), FirstEnergy Corp., the Tennessee Valley Authority, and Dravo Lime, Inc. Sulfuric acid controls are becoming of increasing interest to power generators with coal-fired units for a number of reasons. Sulfuric acid is a Toxic Release Inventory species and can cause a variety of plant operation problems such as air heater plugging and fouling, back-end corrosion, and plume opacity. These issues will likely be exacerbated with the retrofit of selective catalytic reduction (SCR) for NO{sub x} control on many coal-fired plants, as SCR catalysts are known to further oxidize a portion of the flue gas SO{sub 2} to SO{sub 3}. The project previously tested the effectiveness of furnace injection of four different calcium-and/or magnesium-based alkaline sorbents on full-scale utility boilers. These reagents were tested during four one- to two-week tests conducted on two FirstEnergy Bruce Mansfield Plant (BMP) units. One of the sorbents tested was a magnesium hydroxide byproduct slurry produced from a modified Thiosorbic{reg_sign} Lime wet flue gas desulfurization system. The other three sorbents are available commercially and include dolomite, pressure-hydrated dolomitic lime, and commercial magnesium hydroxide. The dolomite reagent was injected as a dry powder through out-of-service burners, while the other three reagents were injected as slurries through air-atomizing nozzles inserted through the front wall of the upper furnace, either across from the nose of the furnace or across from the pendant superheater tubes. After completing the four one- to two-week tests, the most promising sorbents were selected for

  2. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID CONTROL

    SciTech Connect (OSTI)

    Gary M. Blythe

    2003-06-01

    This document summarizes progress on Cooperative Agreement DE-FC26-99FT40718, Furnace Injection of Alkaline Sorbents for Sulfuric Acid Control, during the time period October 1, 2002 through March 31, 2003. The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The coincident removal of hydrochloric acid and hydrofluoric acid is also being determined, as is the removal of arsenic, a known poison for NO{sub x} selective catalytic reduction (SCR) catalysts. EPRI, the Tennessee Valley Authority (TVA), FirstEnergy Corporation, American Electric Power (AEP) and the Dravo Lime Company are project co-funders. URS Group is the prime contractor. This is the seventh reporting period for the subject Cooperative Agreement. During previous reporting periods, two long-term sorbent injection tests were conducted, one on Unit 3 at FirstEnergy's Bruce Mansfield Plant (BMP) and one on Unit 1 at AEP's Gavin Plant. Those tests determined the effectiveness of injecting alkaline slurries into the upper furnace of the boiler as a means of controlling sulfuric acid emissions from these units. The alkaline slurries tested included commercially available magnesium hydroxide slurry (Gavin Plant), and a byproduct magnesium hydroxide slurry (both Gavin Plant and BMP). The tests showed that injecting either the commercial or the byproduct magnesium hydroxide slurry could achieve up to 70-75% overall sulfuric acid removal. At BMP, the overall removal was limited by the need to maintain acceptable electrostatic precipitator (ESP) particulate control performance. At Gavin Plant, the overall sulfuric acid removal was limited because the furnace injected sorbent was less effective at removing SO{sub 3} formed across the SCR system installed on the unit for NO{sub x} control than at removing SO{sub 3} formed in the furnace. The SO3 removal results were presented in the semi

  3. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID REMOVAL

    SciTech Connect (OSTI)

    Gary M. Blythe

    2004-01-01

    The objective of this project has been to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The project was co-funded by the U.S. DOE National Energy Technology Laboratory under Cooperative Agreement DE-FC26-99FT40718, along with EPRI, the American Electric Power Company (AEP), FirstEnergy Corporation, the Tennessee Valley Authority, and Carmeuse North America. Sulfuric acid controls are becoming of increased interest for coal-fired power generating units for a number of reasons. In particular, sulfuric acid can cause plant operation problems such as air heater plugging and fouling, back-end corrosion, and plume opacity. These issues will likely be exacerbated with the retrofit of selective catalytic reduction (SCR) for NOX control, as SCR catalysts are known to further oxidize a portion of the flue gas SO{sub 2} to SO{sub 3}. The project tested the effectiveness of furnace injection of four different magnesium-based or dolomitic alkaline sorbents on full-scale utility boilers. These reagents were tested during one- to two-week tests conducted on two FirstEnergy Bruce Mansfield Plant (BMP) units. One of the sorbents tested was a magnesium hydroxide slurry byproduct from a modified Thiosorbic{reg_sign} Lime wet flue gas desulfurization process. The other three sorbents are available commercially and include dolomite, pressure-hydrated dolomitic lime, and commercially available magnesium hydroxide. The dolomite reagent was injected as a dry powder through out-of-service burners. The other three reagents were injected as slurries through air-atomizing nozzles inserted through the front wall of the upper furnace. After completing the four one- to two-week tests, the most promising sorbents were selected for longer-term (approximately 25-day) full-scale tests on two different units. The longer-term tests were conducted to confirm sorbent effectiveness over extended operation on two

  4. Elucidating the Role of Ferrous Ion Cocatalyst in Enhancing Dilute Acid Pretreatment of Lignocellulosic Biomass

    SciTech Connect (OSTI)

    Wei, H.; Donohoe, B. S.; Vinzant, T. B.; Ciesielski, P. N.; Wang, W.; Gedvilas, L. M.; Zeng, Y.; Johnson, D. K.; Ding, S. Y.; Himmel, M. E.; Tucker, M. P.

    2011-01-01

    Recently developed iron cocatalyst enhancement of dilute acid pretreatment of biomass is a promising approach for enhancing sugar release from recalcitrant lignocellulosic biomass. However, very little is known about the underlying mechanisms of this enhancement. In the current study, our aim was to identify several essential factors that contribute to ferrous ion-enhanced efficiency during dilute acid pretreatment of biomass and to initiate the investigation of the mechanisms that result in this enhancement. During dilute acid and ferrous ion cocatalyst pretreatments, we observed concomitant increases in solubilized sugars in the hydrolysate and reducing sugars in the (insoluble) biomass residues. We also observed enhancements in sugar release during subsequent enzymatic saccharification of iron cocatalyst-pretreated biomass. Fourier transform Raman spectroscopy showed that major peaks representing the C-O-C and C-H bonds in cellulose are significantly attenuated by iron cocatalyst pretreatment. Imaging using Prussian blue staining indicated that Fe{sup 2+} ions associate with both cellulose/xylan and lignin in untreated as well as dilute acid/Fe{sup 2+} ion-pretreated corn stover samples. Analyses by scanning electron microscopy and transmission electron microscopy revealed structural details of biomass after dilute acid/Fe{sup 2+} ion pretreatment, in which delamination and fibrillation of the cell wall were observed. By using this multimodal approach, we have revealed that (1) acid-ferrous ion-assisted pretreatment increases solubilization and enzymatic digestion of both cellulose and xylan to monomers and (2) this pretreatment likely targets multiple chemistries in plant cell wall polymer networks, including those represented by the C-O-C and C-H bonds in cellulose.

  5. CE IGCC Repowering plant sulfuric acid plant. Topical report, June 1993

    SciTech Connect (OSTI)

    Chester, A.M.

    1993-12-01

    A goal of the CE IGCC Repowering project is to demonstrate a hot gas clean-up system (HGCU), for the removal of sulfur from the product gas stream exiting the gasifier island. Combustion Engineering, Inc. (ABB CE) intends to use a HGCU developed by General Electric Environmental Services (GEESI). The original design of this system called for the installation of the HGCU, with a conventional cold gas clean-up system included as a full-load operational back-up. Each of these systems removes sulfur compounds and converts them into an acid off-gas. This report deals with the investigation of equipment to treat this off-gas, recovering these sulfur compounds as elemental sulfur, sulfuric acid or some other form. ABB CE contracted ABB Lummus Crest Inc. (ABB LCI) to perform an engineering evaluation to compare several such process options. This study concluded that the installation of a sulfuric acid plant represented the best option from both a technical and economic point of view. Based on this evaluation, ABB CE specified that a sulfuric acid plant be installed to remove sulfur from off-gas exiling the gas clean-up system. ABB LCI prepared a request for quotation (RFQ) for the construction of a sulfuric acid production plant. Monsanto Enviro-Chem Inc. presented the only proposal, and was eventually selected as the EPC contractor for this system.

  6. Laboratory studies of 2H evaporator scale dissolution in dilute nitric acid

    SciTech Connect (OSTI)

    Oji, L.

    2014-09-23

    The rate of 2H evaporator scale solids dissolution in dilute nitric acid has been experimentally evaluated under laboratory conditions in the SRNL shielded cells. The 2H scale sample used for the dissolution study came from the bottom of the evaporator cone section and the wall section of the evaporator cone. The accumulation rate of aluminum and silicon, assumed to be the two principal elemental constituents of the 2H evaporator scale aluminosilicate mineral, were monitored in solution. Aluminum and silicon concentration changes, with heating time at a constant oven temperature of 90 deg C, were used to ascertain the extent of dissolution of the 2H evaporator scale mineral. The 2H evaporator scale solids, assumed to be composed of mostly aluminosilicate mineral, readily dissolves in 1.5 and 1.25 M dilute nitric acid solutions yielding principal elemental components of aluminum and silicon in solution. The 2H scale dissolution rate constant, based on aluminum accumulation in 1.5 and 1.25 M dilute nitric acid solution are, respectively, 9.21E-04 ± 6.39E-04 min{sup -1} and 1.07E-03 ± 7.51E-05 min{sup -1}. Silicon accumulation rate in solution does track the aluminum accumulation profile during the first few minutes of scale dissolution. It however diverges towards the end of the scale dissolution. This divergence therefore means the aluminum-to-silicon ratio in the first phase of the scale dissolution (non-steady state conditions) is different from the ratio towards the end of the scale dissolution. Possible causes of this change in silicon accumulation in solution as the scale dissolution progresses may include silicon precipitation from solution or the 2H evaporator scale is a heterogeneous mixture of aluminosilicate minerals with several impurities. The average half-life for the decomposition of the 2H evaporator scale mineral in 1.5 M nitric acid is 12.5 hours, while the half-life for the decomposition of the 2H evaporator scale in 1.25 M nitric acid is 10

  7. Unusual refinery boiler tube failures due to corrosion by sulfuric acid induced by steam leaks

    SciTech Connect (OSTI)

    Lopez-Lopez, D.; Wong-Moreno, A.

    1998-12-31

    Corrosion by sulfuric acid in boilers is a low probability event because gas temperature and metal temperature of boiler tubes are high enough to avoid the condensation of sulfuric acid from flue gases. This degradation mechanism is frequently considered as an important cause of air preheaters materials degradation, where flue gases are cooled by heat transfer to the combustion air. Corrosion is associated to the presence of sulfuric acid, which condensates if metal temperature (or gas temperature) is below of the acid dew point. In economizer tubes, sulfuric acid corrosion is an unlikely event because flue gas and tube temperatures are normally over the acid dewpoint. In this paper, the failure analysis of generator tubes (similar to the economizer of bigger boilers) of two small oil-fired subcritical boilers is reported. It is concluded that sulfuric acid corrosion was the cause of the failure. The sulfuric acid condensation was due to the contact of flue gases containing SO{sub 3} with water-steam spray coming from leaks at the interface of rolled tube to the drum. Considering the information gathered from these two cases studied, an analysis of this failure mechanism is presented including a description of the thermodynamics condition of water leaking from the drum, and an analysis of the factors favoring it.

  8. Optimization of wastewater microalgae saccharification using dilute acid hydrolysis for acetone, butanol, and ethanol fermentation

    SciTech Connect (OSTI)

    Castro, Yessica; Ellis, Joshua T.; Miller, Charles D.; Sims, Ronald C.

    2015-02-01

    Exploring and developing sustainable and efficient technologies for biofuel production are crucial for averting global consequences associated with fuel shortages and climate change. Optimization of sugar liberation from wastewater algae through acid hydrolysis was determined for subsequent fermentation to acetone, butanol, and ethanol (ABE) by Clostridium saccharoperbutylacetonicum N1-4. Acid concentration, retention time, and temperature were evaluated to determine optimal hydrolysis conditions by assessing the sugar and ABE yield as well as the associated costs. Sulfuric acid concentrations ranging from 0-1.5 M, retention times of 40-120 min, and temperatures from 23°C- 90°C were combined to form a full factorial experiment. Acid hydrolysis pretreatment of 10% dried wastewater microalgae using 1.0 M sulfuric acid for 120 min at 80-90°C was found to be the optimal parameters, with a sugar yield of 166.1 g for kg of dry algae, concentrations of 5.23 g/L of total ABE, and 3.74 g/L of butanol at a rate of USD $12.83 per kg of butanol.

  9. ENERGY EFFICIENCY LIMITS FOR A RECUPERATIVE BAYONET SULFURIC ACID DECOMPOSITION REACTOR FOR SULFUR CYCLE THERMOCHEMICAL HYDROGEN PRODUCTION

    SciTech Connect (OSTI)

    Gorensek, M.; Edwards, T.

    2009-06-11

    A recuperative bayonet reactor design for the high-temperature sulfuric acid decomposition step in sulfur-based thermochemical hydrogen cycles was evaluated using pinch analysis in conjunction with statistical methods. The objective was to establish the minimum energy requirement. Taking hydrogen production via alkaline electrolysis with nuclear power as the benchmark, the acid decomposition step can consume no more than 450 kJ/mol SO{sub 2} for sulfur cycles to be competitive. The lowest value of the minimum heating target, 320.9 kJ/mol SO{sub 2}, was found at the highest pressure (90 bar) and peak process temperature (900 C) considered, and at a feed concentration of 42.5 mol% H{sub 2}SO{sub 4}. This should be low enough for a practical water-splitting process, even including the additional energy required to concentrate the acid feed. Lower temperatures consistently gave higher minimum heating targets. The lowest peak process temperature that could meet the 450-kJ/mol SO{sub 2} benchmark was 750 C. If the decomposition reactor were to be heated indirectly by an advanced gas-cooled reactor heat source (50 C temperature difference between primary and secondary coolants, 25 C minimum temperature difference between the secondary coolant and the process), then sulfur cycles using this concept could be competitive with alkaline electrolysis provided the primary heat source temperature is at least 825 C. The bayonet design will not be practical if the (primary heat source) reactor outlet temperature is below 825 C.

  10. Fermentation of dilute acid pretreated Populus by Clostridium thermocellum, Caldicellulosiruptor bescii, and Caldicellulosiruptor obsidiansis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yee, Kelsey L.; Rodriguez, Jr., Miguel; Hamilton, Choo Yieng; Hamilton-Brehm, Scott D.; Thompson, Olivia A.; Elkins, James G.; Davison, Brian H.; Mielenz, Jonathan R.

    2015-07-25

    Consolidated bioprocessing (CBP), which merges enzyme production, biomass hydrolysis, and fermentation into a single step, has the potential to become an efficient and economic strategy for the bioconversion of lignocellulosic feedstocks to transportation fuels or chemicals. In this study, we evaluated Clostridium thermocellum, Caldicellulosiruptor bescii, and Caldicellulosiruptor obsidiansis, three , thermophilic,cellulolytic, mixed-acid fermenting candidate CBP microorganisms, for their fermentation capabilities using dilute acid pretreated Populus as a model biomass feedstock. Under pH controlled, anaerobic fermentation conditions, each candidate successfully digested a minimum of 75% of the cellulose from dilute acid pretreated Populus, as indicated by an increase in planktonic cellsmore » and end-product metabolites and a concurrent decrease in glucan content. C. thermocellum, which employs a cellulosomal approach to biomass degradation, required 120 hours to achieve 75% cellulose utilization. In contrast, the non-cellulosomal, secreted hydrolytic enzyme system of the Caldicellulosiruptor sp. required 300 hours to achieve similar results. End-point fermentation conversions for C. thermocellum, C. bescii, and C. obsidiansis were determined to be 0.29, 0.34, and 0.38 grams of total metabolites per gram of loaded glucan, respectively. This data provide a starting point for future strain engineering efforts that can serve to improve the biomass fermentation capabilities of these three promising candidate CBP platforms.« less

  11. Airborne measurements of sulfur dioxide, dimethyl sulfide, carbon disulfide, and carbonyl sulfide by isotope dilution gas chromatography/mass spectrometry

    SciTech Connect (OSTI)

    Bandy, A.R.; Thornton, D.C.; Driedger, A.R. III [Drexel Univ., Philadelphia, PA (United States)

    1993-12-01

    A gas chromatograph/mass spectrometer is described for determining atmospheric sulfur dioxide, carbon disulfide, dimethyl sulfide, and carbonyl sulfide from aircraft and ship platforms. Isotopically labelled variants of each analyte were used as internal standards to achieve high precision. The lower limit of detection for each species for an integration time of 3 min was 1 pptv for sulfur dioxide and dimethyl sulfide and 0.2 pptv for carbon disulfide and carbonyl sulfide. All four species were simultaneously determined with a sample frequency of one sample per 6 min or greater. When only one or two species were determined, a frequency of one sample per 4 min was achieved. Because a calibration is included in each sample, no separate calibration sequence was needed. Instrument warmup was only a few minutes. The instrument was very robust in field deployments, requiring little maintenance.

  12. Structural Transformation of Isolated Poplar and Switchgrass Lignins from Dilute Acid Pretreatment

    SciTech Connect (OSTI)

    Sun, Qining; Pu, Yunqiao; Meng, Xianzhi; Wells, Tyrone; Ragauskas, Arthur J.

    2015-08-27

    A key step in conversion of cellulosic biomass into sustainable fuels and chemicals is thermochemical pretreatment to reduce plant cell wall recalcitrance. Obtaining an improved understanding of the fundamental chemistry of lignin, the most recalcitrant component of biomass, during pretreatment is critical to the continued development of renewable biofuel production. To examine the intrinsic chemistry of lignin during dilute acid pretreatment (DAP), lignin was isolated from poplar and switchgrass using a cellulolytic enzyme system and then treated under DAP conditions. These results highlight that lignin is subjected to depolymerization reactions within the first 2 min of dilute acid pretreatment and these changes are accompanied by increased generation of aliphatic and phenolic hydroxyl groups of lignin. This is followed by a competing set of depolymerization and repolymerization reactions that lead to a decrease in the content of guaiacyl lignin units and an increase in condensed lignin units as the reaction residence time is extended beyond 5 min. Finally, we showed that a detailed comparison of changes in functional groups and molecular weights of cellulolytic enzyme lignins with different structural parameters, related to the recalcitrant properties of lignin, could be successfully altered during DAP conditions.

  13. Structural Transformation of Isolated Poplar and Switchgrass Lignins from Dilute Acid Pretreatment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sun, Qining; Pu, Yunqiao; Meng, Xianzhi; Wells, Tyrone; Ragauskas, Arthur J.

    2015-08-27

    A key step in conversion of cellulosic biomass into sustainable fuels and chemicals is thermochemical pretreatment to reduce plant cell wall recalcitrance. Obtaining an improved understanding of the fundamental chemistry of lignin, the most recalcitrant component of biomass, during pretreatment is critical to the continued development of renewable biofuel production. To examine the intrinsic chemistry of lignin during dilute acid pretreatment (DAP), lignin was isolated from poplar and switchgrass using a cellulolytic enzyme system and then treated under DAP conditions. These results highlight that lignin is subjected to depolymerization reactions within the first 2 min of dilute acid pretreatment andmore » these changes are accompanied by increased generation of aliphatic and phenolic hydroxyl groups of lignin. This is followed by a competing set of depolymerization and repolymerization reactions that lead to a decrease in the content of guaiacyl lignin units and an increase in condensed lignin units as the reaction residence time is extended beyond 5 min. Finally, we showed that a detailed comparison of changes in functional groups and molecular weights of cellulolytic enzyme lignins with different structural parameters, related to the recalcitrant properties of lignin, could be successfully altered during DAP conditions.« less

  14. Improved Multivariate Calibration Models for Corn Stover Feedstock and Dilute-Acid Pretreated Corn Stover

    SciTech Connect (OSTI)

    Wolfrum, E. J.; Sluiter, A. D.

    2009-01-01

    We have studied rapid calibration models to predict the composition of a variety of biomass feedstocks by correlating near-infrared (NIR) spectroscopic data to compositional data produced using traditional wet chemical analysis techniques. The rapid calibration models are developed using multivariate statistical analysis of the spectroscopic and wet chemical data. This work discusses the latest versions of the NIR calibration models for corn stover feedstock and dilute-acid pretreated corn stover. Measures of the calibration precision and uncertainty are presented. No statistically significant differences (p = 0.05) are seen between NIR calibration models built using different mathematical pretreatments. Finally, two common algorithms for building NIR calibration models are compared; no statistically significant differences (p = 0.05) are seen for the major constituents glucan, xylan, and lignin, but the algorithms did produce different predictions for total extractives. A single calibration model combining the corn stover feedstock and dilute-acid pretreated corn stover samples gave less satisfactory predictions than the separate models.

  15. Redistribution of Xylan in Maize Cell Walls During Dilute Acid Pretreatment

    SciTech Connect (OSTI)

    Brunecky, R.; Vinzant, T. B.; Porter, S. E.; Donohoe, B. S.; Johnson, D. K.; Himmel, M. E.

    2009-04-15

    Developing processes for the conversion of biomass for use in transportation fuels production is becoming a critically important economic and engineering challenge. Dilute acid pretreatment is a promising technology for increasing the enzymatic digestibility of lignocellulosic biomass. However, a deeper understanding of the pretreatability of biomass is needed so that the rate of formation and yields of sugars can be increased. Xylan is an important hemicellulosic component of the plant cell wall and acts as a barrier to cellulose, essentially blocking cellulase action. To better understand xylan hydrolysis in corn stover, we have studied changes in the distribution of xylan caused by dilute acid pretreatment using correlative microscopy. A dramatic loss of xylan antibody signal from the center of the cell wall and an increase or retention of xylan at the plasma membrane interface and middle lamella of the cell were observed by confocal laser scanning microscopy (CLSM). We also observed a reduction in xylan fluorescence signal by CLSM that is generally consistent with the decrease in xylan content measured experimentally in the bulk sample, however, the compartmentalization of this xylan retention was not anticipated.

  16. Separation of glycols from dilute aqueous solutions via complexation with boronic acids

    SciTech Connect (OSTI)

    Randel, L.A.; King, C.J.

    1991-07-01

    This work examines methods of separating low molecular weight glycols from dilute aqueous solution. Extraction into conventional solvents is generally not economical, since, in the literature reviewed, distribution ratios for the two- to four-carbon glycols are all less than one. Distribution ratios can be increased, however, by incorporating into the organic phase an extracting agent that will complex with the solute of interest. The extracting agent investigated in this work is 3-nitrophenylboronic acid (NPBA). NPBA, a boric acid derivative, reversibly complexes with many glycols. The literature on complexation of borate and related compounds with glycols, including mechanistic data, measurement techniques, and applications to separation processes, provides information valuable for designing experiments with NPBA and is reviewed herein. 88 refs., 15 figs., 24 tabs.

  17. Process for recovery of sulfur from acid gases

    DOE Patents [OSTI]

    Towler, Gavin P.; Lynn, Scott

    1995-01-01

    Elemental sulfur is recovered from the H.sub.2 S present in gases derived from fossil fuels by heating the H.sub.2 S with CO.sub.2 in a high-temperature reactor in the presence of a catalyst selected as one which enhances the thermal dissociation of H.sub.2 S to H.sub.2 and S.sub.2. The equilibrium of the thermal decomposition of H.sub.2 S is shifted by the equilibration of the water-gas-shift reaction so as to favor elemental sulfur formation. The primary products of the overall reaction are S.sub.2, CO, H.sub.2 and H.sub.2 O. Small amounts of COS, SO.sub.2 and CS.sub.2 may also form. Rapid quenching of the reaction mixture results in a substantial increase in the efficiency of the conversion of H.sub.2 S to elemental sulfur. Plant economy is further advanced by treating the product gases to remove byproduct carbonyl sulfide by hydrolysis, which converts the COS back to CO.sub.2 and H.sub.2 S. Unreacted CO.sub.2 and H.sub.2 S are removed from the product gas and recycled to the reactor, leaving a gas consisting chiefly of H.sub.2 and CO, which has value either as a fuel or as a chemical feedstock and recovers the hydrogen value from the H.sub.2 S.

  18. Impact of Recycling Stillage on Conversion of Dilute Sulfuric Acid Pretreated Corn Stover to Ethanol (Poster)

    SciTech Connect (OSTI)

    Mohagheghi, A.; Schell, D. J.

    2009-11-01

    A description of methods and results from an experiment designed to assess the impact of process water recycle on corn stover-to-ethanol conversion process performance.

  19. Effects of Dilute Acid Pretreatment on Cellulose DP and the Relationship Between DP Reduction and Cellulose Digestibility

    SciTech Connect (OSTI)

    Wang, W.; Chen, X.; Tucker, M.; Himmel, M. E.; Johnson, D. K.

    2012-01-01

    The degree of polymerization(DP) of cellulose is considered to be one of the most important properties affecting the enzymatic hydrolysis of cellulose. Various pure cellulosic and biomass materials have been used in a study of the effect of dilute acid treatment on cellulose DP. A substantial reduction in DP was found for all pure cellulosic materials studied even at conditions that would be considered relatively mild for pretreatment. The effect of dilute acid pretreatment on cellulose DP in biomass samples was also investigated. Corn stover pretreated with dilute acid under the most optimal conditions contained cellulose with a DPw in the range of 1600{approx}3500, which is much higher than the level-off DP(DPw 150{approx}300) obtained with pure celluloses. The effect of DP reduction on the saccharification of celluloses was also studied. From this study it does not appear that cellulose DP is a main factor affecting cellulose saccharification.

  20. Effects of Fuel Dilution with Biodiesel on Lubricant Acidity, Oxidation and Corrosion

    Broader source: Energy.gov [DOE]

    In-cylinder fuel injection to produce rich exhaust for regeneration of lean NOx trap catalyst and diesel particulate filter results in substantial fuel dilution of lubricating oil cause changes of lubricating oil properties and scuffing of engine components.

  1. Combined Dilute Acid and Solvent Based Pretreatment of Agricultural Wastes for Efficient Lignocellulosic Fractionation and Biofuels Production

    SciTech Connect (OSTI)

    Brodeur, G.; Ramakrishnan, S.; Wilson, C.; Telotte, J.; Collier, J.; Stickel, J.

    2013-01-01

    A true biorefinery for processing lignocellulosic biomass should achieve maximum utilization of all major constituents (cellulose, hemicellulose, & lignin) within the feedstock. In this work a combined pretreatment process of dilute acid (DA) and N-methyl morpholine N-oxide (NMMO) is described that allows for both fractionation and subsequent complete hydrolysis of the feedstocks (corn stover and sugarcane bagasse). During this multi-step processing, the dilute acid pretreatment solubilizes the majority (>90%) of the hemicellulosic fraction, while the NMMO treatment yields a cellulosic fraction that is completely digestible within 48 hours at low enzyme loadings. With both the cellulosic and hemicellulosic fractions being converted into separate, dissolved sugar fractions, the remaining portion is nearly pure lignin. When used independently, DA and NMMO pretreatments are only able to achieve ~80% and ~45% cellulosic conversion, respectively. Mass balance calculations along with experimental results are used to illustrate the feasibility of separation and recycling of NMMO.

  2. Advances in Acid Concentration Membrane Technology for the Sulfur-Iodine Thermochemical Cycle

    SciTech Connect (OSTI)

    Frederick F. Stewart; Christopher J. Orme

    2006-11-01

    One of the most promising cycles for the thermochemical generation of hydrogen is the Sulfur-Iodine (S-I) process, where aqueous HI is thermochemically decomposed into H2 and I2 at approximately 350 degrees Celsius. Regeneration of HI is accomplished by the Bunsen reaction (reaction of SO2, water, and iodine to generate H2SO4 and HI). Furthermore, SO2 is regenerated from the decomposition of H2SO4 at 850 degrees Celsius yielding the SO2 as well as O2. Thus, the cycle actually consists of two concurrent oxidation-reduction loops. As HI is regenerated, co-produced H2SO4 must be separated so that each may be decomposed. Current flowsheets employ a large amount (~83 mol% of the entire mixture) of elemental I2 to cause the HI and the H2SO4 to separate into two phases. To aid in the isolation of HI, which is directly decomposed into hydrogen, water and iodine must be removed. Separation of iodine is facilitated by removal of water. Sulfuric acid concentration is also required to facilitate feed recycling to the sulfuric acid decomposer. Decomposition of the sulfuric acid is an equilibrium limited process that leaves a substantial portion of the acid requiring recycle. Distillation of water from sulfuric acid involves significant corrosion issues at the liquid-vapor interface. Thus, it is desirable to concentrate the acid without boiling. Recent efforts at the INL have concentrated on applying pervaporation through Nafion-117, Nafion-112, and sulfonated poly(etheretherketone) (S-PEEK) membranes for the removal of water from HI/water and HI/Iodine/water feedstreams. In pervaporation, a feed is circulated at low pressure across the upstream side of the membrane, while a vacuum is applied downstream. Selected permeants sorb into the membrane, transport through it, and are vaporized from the backside. Thus, a concentration gradient is established, which provides the driving force for transport. In this work, membrane separations have been performed at temperatures as high as

  3. Ice Nucleation of Bare and Sulfuric Acid-coated Mineral Dust Particles and Implication for Cloud Properties

    SciTech Connect (OSTI)

    Kulkarni, Gourihar R.; Sanders, Cassandra N.; Zhang, Kai; Liu, Xiaohong; Zhao, Chun

    2014-08-27

    Ice nucleation properties of different dust species coated with soluble material are not well understood. We determined the ice nucleation ability of bare and sulfuric acid coated mineral dust particles as a function of temperature (-25 to -35 deg C) and relative humidity with respect to water (RHw). Five different mineral dust species: Arizona test dust (ATD), illite, montmorillonite, quartz and kaolinite were dry dispersed and size-selected at 150 nm and exposed to sulfuric acid vapors in the coating apparatus. The condensed sulfuric acid soluble mass fraction per particle was estimated from the cloud condensation nuclei activated fraction measurements. The fraction of dust particles nucleating ice at various temperatures and RHw was determined using a compact ice chamber. In water-subsaturated conditions, compared to bare dust particles, we found that only coated ATD particles showed suppression of ice nucleation ability while other four dust species did not showed the effect of coating on the fraction of particles nucleating ice. The results suggest that interactions between the dust surface and sulfuric acid vapor are important, such that interactions may or may not modify the surface via chemical reactions with sulfuric acid. At water-supersaturated conditions we did not observed the effect of coating, i.e. the bare and coated dust particles had similar ice nucleation behavior.

  4. Sulfuric acid and hydrogen peroxide surface passivation effects on AlGaN/GaN high electron mobility transistors

    SciTech Connect (OSTI)

    Zaidi, Z. H. Lee, K. B.; Qian, H.; Jiang, S.; Houston, P. A.; Guiney, I.; Wallis, D. J.; Humphreys, C. J.

    2014-12-28

    In this work, we have compared SiN{sub x} passivation, hydrogen peroxide, and sulfuric acid treatment on AlGaN/GaN HEMTs surface after full device fabrication on Si substrate. Both the chemical treatments resulted in the suppression of device pinch-off gate leakage current below 1??A/mm, which is much lower than that for SiN{sub x} passivation. The greatest suppression over the range of devices is observed with the sulfuric acid treatment. The device on/off current ratio is improved (from 10{sup 4}10{sup 5} to 10{sup 7}) and a reduction in the device sub-threshold (S.S.) slope (from ?215 to 90?mV/decade) is achieved. The sulfuric acid is believed to work by oxidizing the surface which has a strong passivating effect on the gate leakage current. The interface trap charge density (D{sub it}) is reduced (from 4.86 to 0.90??10{sup 12?}cm{sup ?2} eV{sup ?1}), calculated from the change in the device S.S. The gate surface leakage current mechanism is explained by combined Mott hopping conduction and Poole Frenkel models for both untreated and sulfuric acid treated devices. Combining the sulfuric acid treatment underneath the gate with the SiN{sub x} passivation after full device fabrication results in the reduction of D{sub it} and improves the surface related current collapse.

  5. Extraction equilibria of acetic and propionic acids from dilute aqueous solution by several solvents

    SciTech Connect (OSTI)

    Fahim, M.A. )

    1992-10-01

    Extraction equilibria of acetic acid and propionic acid with hexane solutions of trioctyl amine, trioctyl phosphine oxide, and tributyl phosphate were studied. The species formed in the systems were estimated, and the distribution coefficients and the equilibrium constants for these species were evaluated.s

  6. Hydrolysis of dilute acid pretreated mixed hardwood and purified microcrystalline cellulose by cell-free broth from Clostridium thermocellum

    SciTech Connect (OSTI)

    Lynd, L.R.; Grethlein, H.E.

    1987-01-01

    The cellulase activity in cell-free broths from Clostridium thermocellum is examined on both dilute-acid-pretreated mixed hardwood (90% maple, 10% birch) and Avicel. Experiments were conducted in vitro in order to distinguish properties of the cellulase from properties of the organism and to evaluate the effectiveness of C. thermocellum cellulase in the hydrolysis of a naturally occurring, lignin-containing substrate. The results obtained establish that essentially quantitative hydrolysis of cellulose from pretreated mixed hardwood is possible using this enzyme system. Pretreatment with 1% H/sub 2/SO/sub 4/ and a 9-s residence time at 220, 210, 200, and 180/sup 0/C allowed yields after enzymatic hydrolysis (percentage of glucan solubilized/glucan potentially solubilized) of 97.8, 86.1, 82.0, and 34.6%, respectively. Enzymatic hydrolysis of mixed hardwood with no pretreatment resulted in a yield of 10.1%. Hydrolysis yields of greater than 95% were obtained from 0.6 g/l mixed hardwood pretreated at 220/sup 0/C in 7 hours at broth strengths of 60 and 80% (v/v) and in approximately 48 hours with 33% broth. Hydrolysis of pretreated mixed hardwood is compared to hydrolysis of Avicel. The initial rate of Avicel hydrolysis saturates with respect to enzyme, whereas the initial rate of hydrolysis of pretreated wood is proportional to the amount of enzyme present. Initial hydrolysis rates for pretreated wood and Avicel at 0.6 g/l are greater for wood at low broth dilutions (1.25:1 to 5:1) by up to 2.7-fold and greater for Avicel at high broth dilutions (5:1 to 50:1) by up to 4.3-fold. Maximum rates of hydrolysis are achieved at less than 2 g substrate/liter for both pretreated wood and Avicel).

  7. Effect of pelleting on the recalcitrance and bioconversion of dilute-acid pretreated corn stover

    SciTech Connect (OSTI)

    Allison E Ray; Amber Hoover; Gary Gresham

    2012-07-01

    Background: Knowledge regarding the performance of densified biomass in biochemical processes is limited. The effects of densification on biochemical conversion are explored here. Methods: Pelleted corn stover samples were generated from bales that were milled to 6.35 mm. Low-solids acid pretreatment and simultaneous saccharification and fermentation were performed to evaluate pretreatment efficacy and ethanol yields achieved for pelleted and ground stover (6.35 mm and 2 mm) samples. Both pelleted and 6.35-mm ground stover were evaluated using a ZipperClave® reactor under high-solids, process-relevant conditions for multiple pretreatment severities (Ro), followed by enzymatic hydrolysis of the washed, pretreated solids. Results: Monomeric xylose yields were significantly higher for pellets (approximately 60%) than for ground formats (approximately 38%). Pellets achieved approximately 84% of theoretical ethanol yield (TEY); ground stover formats had similar profiles, reaching approximately 68% TEY. Pelleting corn stover was not detrimental to pretreatment efficacy for both low- and high-solids conditions, and even enhanced ethanol yields.

  8. Effect of roasting with ammonium sulfate and sulfuric acid on the extraction of copper and cobalt from copper converter slag

    SciTech Connect (OSTI)

    Hamamci, C.; Ziyadanogullari, B. )

    1991-08-01

    Copper converter slag, provided by Ergani Copper Co. of Etibank and containing 2.56% copper and 0.22% cobalt, was roasted with ammonium sulfate. The effects of such parameters as temperature (200-600C), duration of roasting (15-120 min), and amount of ammonium sulfate (0.5-2.5 times stoichiometric) have been studied. Under optimum conditions (slag size, {minus}100 mesh; stoichiometric requirement of ammonium sulfate; roasting temperature of 400 C for 60 min), the authors obtained 88% Cu and 67% Co by extraction. Similar studies were carried out with concentrated sulfuric acid. The influence of experimental variables such as roasting temperature (25-300C), roasting period (30-120 min), and amount of sulfuric acid (0.5-2 times stoichiometric) has been studied. Under atmospheric conditions, i.e., at 200C and a roasting period of 60 min with 1.5 times the stoichiometric amount of sulfuric acid, recoveries of copper and cobalt were 82 and 96% respectively.

  9. Epidemiological-environemental study of lead acid battery workers. III. Chronic effects of sulfuric acid on the respiratory system and teeth

    SciTech Connect (OSTI)

    Gamble, J.; Jones, W.; Hancock, J.; Meckstroth, R.L.

    1984-10-01

    The effects of long-term exposure to sulfuric acid mist on the teeth and respiratory system were studied in 248 workers in five plants manufacturing lead acid batteries. The prevalence of cough, phlegm, dyspnea, and wheezing as determined by questionnaire were not associated with estimates of cumulative acid exposure. There was only one case of irregular opacities seen on the chest radiographs. There was no statistically significant association of reduced FEV/sub 1/ peak flow, FEF/sub 50/, and FEF/sub 75/ with acid exposure although the higher exposed group had lower mean values. FVC in the high exposure group showed a statistically significant reductioon compared to the low exposure group but there was no significant association when exposure was analyzed as a continuous variable. The ratio of observed to expected prevalence of teeth etching and erosion was about four times greater in the high acid-exposure group. The earliest case of etching occured after 4 months exposure to an estimated average exposure of 0.23 mg/m/sup 3/ sulfuric acid.

  10. Process Design Report for Wood Feedstock: Lignocellulosic Biomass to Ethanol Process Desing and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis Current and Futuristic Scenarios

    SciTech Connect (OSTI)

    Wooley, Robert; Ruth, Mark; Sheehan, John; Ibsen, Kelly; Majdeski, Henry; Galves, Adrian

    1999-07-01

    The National Renewable Energy Laboratory (NREL) has undertaken a complete review and update of the process design and economic model for the biomass-to-ethanol process based on co-current dilute acid prehydrolysis, along with simultaneous saccharification (enzymatic) and co-fermentation. The process design includes the core technologies being researched by the U.S. Department of Energy (DOE): prehydrolysis, simultaneous saccharification and co-fermentation, and cellulase enzyme production.

  11. Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

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

    Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover D. Humbird, R. Davis, L. Tao, C. Kinchin, D. Hsu, and A. Aden National Renewable Energy Laboratory Golden, Colorado P. Schoen, J. Lukas, B. Olthof, M. Worley, D. Sexton, and D. Dudgeon Harris Group Inc. Seattle, Washington and Atlanta, Georgia Technical Report NREL/TP-5100-47764 May 2011 NREL is a national laboratory of the U.S. Department

  12. Corrosion resistance and behavioral characteristics of metals exposed to 70 percent by weight sulfuric acid at elevated temperatures

    SciTech Connect (OSTI)

    Nguyen, D.T.; Farina, G.E.

    1994-10-01

    The development of a concentrated acid hydrolysis process may necessitate the storage, handling, and processing of concentrated solution of sulfuric acid at temperatures in excess of 70{degrees}C. Due to the corrosivity of the sulfuric acid at elevated temperatures, a series of corrosion tests was conducted to determine the corrosion performance and behavior of various construction materials using immersion and electrochemical techniques. Test results showed that among the stainless steels tested, only Carpenter 20Mo-6 performed satisfactorily up to 70{degrees}C. It passivated spontaneously and corroded at a rate less than 40 {mu}m/yr (1.6 mpy). Among numerous nickel-based alloys tested, only Hastelloy B-2 had excellent corrosion resistance up to 100{degrees}C with a corrosion rate less than 50 {mu}/yr (2 mpy), although the alloy did not passivate. Zirconium alloy Zr 702 provided excellent corrosion resistance to 100{degrees}C. The alloy passivated spontaneously, but its passive range decreased, evidently with increase in temperature. Tantalum and KBI-40 provided excellent corrosion protection at all test temperatures. The materials passivated spontaneously with a wide passive range.

  13. ADVANCED SULFUR CONTROL CONCEPTS

    SciTech Connect (OSTI)

    Apostolos A. Nikolopoulos; Santosh K. Gangwal; William J. McMichael; Jeffrey W. Portzer

    2003-01-01

    Conventional sulfur removal in integrated gasification combined cycle (IGCC) power plants involves numerous steps: COS (carbonyl sulfide) hydrolysis, amine scrubbing/regeneration, Claus process, and tail-gas treatment. Advanced sulfur removal in IGCC systems involves typically the use of zinc oxide-based sorbents. The sulfides sorbent is regenerated using dilute air to produce a dilute SO{sub 2} (sulfur dioxide) tail gas. Under previous contracts the highly effective first generation Direct Sulfur Recovery Process (DSRP) for catalytic reduction of this SO{sub 2} tail gas to elemental sulfur was developed. This process is currently undergoing field-testing. In this project, advanced concepts were evaluated to reduce the number of unit operations in sulfur removal and recovery. Substantial effort was directed towards developing sorbents that could be directly regenerated to elemental sulfur in an Advanced Hot Gas Process (AHGP). Development of this process has been described in detail in Appendices A-F. RTI began the development of the Single-step Sulfur Recovery Process (SSRP) to eliminate the use of sorbents and multiple reactors in sulfur removal and recovery. This process showed promising preliminary results and thus further process development of AHGP was abandoned in favor of SSRP. The SSRP is a direct Claus process that consists of injecting SO{sub 2} directly into the quenched coal gas from a coal gasifier, and reacting the H{sub 2}S-SO{sub 2} mixture over a selective catalyst to both remove and recover sulfur in a single step. The process is conducted at gasifier pressure and 125 to 160 C. The proposed commercial embodiment of the SSRP involves a liquid phase of molten sulfur with dispersed catalyst in a slurry bubble-column reactor (SBCR).

  14. PRODUCTION OF TRIFLUOROACETIC ACID COMPOUNDS

    DOE Patents [OSTI]

    Haworth, W.N.; Stacey, M.

    1949-08-30

    A process is described for the preparation of trifluoroacetic acid. Acetone vapor diluted wlth nitrogen and fluorine also diluted with nltrogen are fed separately at a temperature of about 210 deg C into a reaction vessel containing a catalyst mass selected from-the group consisting of silver and gold. The temperature in the reaction vessel is maintained in the range of 200 deg to 250 deg C. The reaction product, trifluoroacetyl fluoride, is absorbed in aqueous alkali solution. Trifluoroacetic acid is recovered from the solution by acidification wlth an acid such as sulfuric followed by steam distillation.

  15. Insights into the effect of dilute acid, hot water and alkaline pretreatment on cellulose accessible surface area and overall porosity of Populus

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Meng, Xianzhi; Wells, Tyrone; Sun, Qining; Huang, Fang; Ragauskas, Arthur J.

    2015-06-19

    Pretreatment is known to render biomass more reactive to cellulase by altering the chemical compositions as well as physical structures of biomass. Simons stain technique along with mercury porosimetry were applied on the acid, neutral, and alkaline pretreated materials to measure the accessible surface area of cellulose and pore size distribution of Populus. Results indicated that acid pretreatment is much more effective than water and alkaline pretreatment in terms of cellulose accessibility increase. Further investigation suggests that lignin does not dictate cellulose accessibility to the extent that hemicellulose does, but it does restrict xylan accessibility which in turn controls themore » access of cellulase to cellulose. The most interesting finding is that severe acid pretreatment significantly decreases the average pore size, i.e., 90% average size decrease could be observed after 60 min dilute acid pretreatment at 160 °C; moreover, the nano-pore space formed between coated microfibrils is increased after pretreatment, especially for the acid pretreatment, suggesting this particular type of biomass porosity is probably the most fundamental barrier to effective enzymatic hydrolysis.« less

  16. Insights into the effect of dilute acid, hot water and alkaline pretreatment on cellulose accessible surface area and overall porosity of Populus

    SciTech Connect (OSTI)

    Meng, Xianzhi; Wells, Tyrone; Sun, Qining; Huang, Fang; Ragauskas, Arthur J.

    2015-06-19

    Pretreatment is known to render biomass more reactive to cellulase by altering the chemical compositions as well as physical structures of biomass. Simons stain technique along with mercury porosimetry were applied on the acid, neutral, and alkaline pretreated materials to measure the accessible surface area of cellulose and pore size distribution of Populus. Results indicated that acid pretreatment is much more effective than water and alkaline pretreatment in terms of cellulose accessibility increase. Further investigation suggests that lignin does not dictate cellulose accessibility to the extent that hemicellulose does, but it does restrict xylan accessibility which in turn controls the access of cellulase to cellulose. The most interesting finding is that severe acid pretreatment significantly decreases the average pore size, i.e., 90% average size decrease could be observed after 60 min dilute acid pretreatment at 160 °C; moreover, the nano-pore space formed between coated microfibrils is increased after pretreatment, especially for the acid pretreatment, suggesting this particular type of biomass porosity is probably the most fundamental barrier to effective enzymatic hydrolysis.

  17. Acid hydrolysis of cellulose to yield glucose

    DOE Patents [OSTI]

    Tsao, George T.; Ladisch, Michael R.; Bose, Arindam

    1979-01-01

    A process to yield glucose from cellulose through acid hydrolysis. Cellulose is recovered from cellulosic materials, preferably by pretreating the cellulosic materials by dissolving the cellulosic materials in Cadoxen or a chelating metal caustic swelling solvent and then precipitating the cellulose therefrom. Hydrolysis is accomplished using an acid, preferably dilute sulfuric acid, and the glucose is yielded substantially without side products. Lignin may be removed either before or after hydrolysis.

  18. Catalyst Activity and Post-operation Analyses of Pt/TiO2 (Rutile) Catalysts Used in the Sulfuric Acid Decomposition Reaction

    SciTech Connect (OSTI)

    Lucia M. Petkovic; Daniel M. Ginosar; Harry W. Rollins; Kyle C. Burch; Patrick J. Pinhero; Helen H. Farrell

    2007-06-01

    Production of hydrogen by splitting of water at lower temperatures than by direct thermal decomposition can be achieved by a series of particular chemical reactions that establish a thermochemical cycle [1]. Among the high number of thermochemical water-splitting cycles proposed in the literature [2], the sulfur-based group is of considerable interest. All the sulfur-based cycles employ the catalytic decomposition of sulfuric acid into SO2 and O2. The produced O2 corresponds to the O2 generated from water in the overall cycle. Research performed at the Idaho National Laboratory [3] has found that even one of the most stables catalysts, Pt supported on low surface area titania, deactivates with time on stream (TOS). To develop an understanding of the factors that cause catalyst deactivation, samples of 1% Pt supported on titania (rutile) catalyst were submitted to flowing concentrated sulfuric acid at 1123 K and atmospheric pressure for different TOSs between 0 and 548 h and a number of chemical and spectroscopic analyses applied to the spent samples.

  19. Improving a recombinant Zymomonas mobilis strain 8b through continuous adaptation on dilute acid pretreated corn stover hydrolysate

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mohagheghi, Ali; Linger, Jeffrey G.; Yang, Shihui; Smith, Holly; Dowe, Nancy; Zhang, Min; Pienkos, Philip T.

    2015-03-31

    Complete conversion of the major sugars of biomass including both the C5 and C6 sugars is critical for biofuel production processes. Several inhibitory compounds like acetate, hydroxymethylfurfural (HMF), and furfural are produced from the biomass pretreatment process leading to ‘hydrolysate toxicity,’ a major problem for microorganisms to achieve complete sugar utilization. Therefore, development of more robust microorganisms to utilize the sugars released from biomass under toxic environment is critical. In this study, we use continuous culture methodologies to evolve and adapt the ethanologenic bacterium Zymomonas mobilis to improve its ethanol productivity using corn stover hydrolysate. The results are the following:more » A turbidostat was used to adapt the Z. mobilis strain 8b in the pretreated corn stover liquor. The adaptation was initiated using pure sugar (glucose and xylose) followed by feeding neutralized liquor at different dilution rates. Once the turbidostat reached 60% liquor content, the cells began washing out and the adaptation was stopped. Several ‘sub-strains’ were isolated, and one of them, SS3 (sub-strain 3), had 59% higher xylose utilization than the parent strain 8b when evaluated on 55% neutralized PCS (pretreated corn stover) liquor. Using saccharified PCS slurry generated by enzymatic hydrolysis from 25% solids loading, SS3 generated an ethanol yield of 75.5% compared to 64% for parent strain 8b. Furthermore, the total xylose utilization was 57.7% for SS3 versus 27.4% for strain 8b. To determine the underlying genotypes in these new sub-strains, we conducted genomic resequencing and identified numerous single-nucleotide mutations (SNPs) that had arisen in SS3. We further performed quantitative reverse transcription PCR (qRT-PCR) on genes potentially affected by these SNPs and identified significant down-regulation of two genes, ZMO0153 and ZMO0776, in SS3 suggesting potential genetic mechanisms behind SS3’s improved

  20. Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons: Dilute-Acid and Enzymatic Deconstruction of Biomass to Sugars and Biological Conversion of Sugars to Hydrocarbons

    SciTech Connect (OSTI)

    Davis, R.; Tao, L.; Tan, E. C. D.; Biddy, M. J.; Beckham, G. T.; Scarlata, C.; Jacobson, J.; Cafferty, K.; Ross, J.; Lukas, J.; Knorr, D.; Schoen, P.

    2013-10-01

    This report describes one potential conversion process to hydrocarbon products by way of biological conversion of lingnocellulosic-dervied sugars. The process design converts biomass to a hydrocarbon intermediate, a free fatty acid, using dilute-acid pretreatement, enzymatic saccharification, and bioconversion. Ancillary areas--feed handling, hydrolysate conditioning, product recovery and upgrading (hydrotreating) to a final blendstock material, wastewater treatment, lignin combusion, and utilities--are also included in the design.

  1. Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    SciTech Connect (OSTI)

    Humbird, D.; Davis, R.; Tao, L.; Kinchin, C.; Hsu, D.; Aden, A.; Schoen, P.; Lukas, J.; Olthof, B.; Worley, M.; Sexton, D.; Dudgeon, D.

    2011-03-01

    This report describes one potential biochemical ethanol conversion process, conceptually based upon core conversion and process integration research at NREL. The overarching process design converts corn stover to ethanol by dilute-acid pretreatment, enzymatic saccharification, and co-fermentation. Building on design reports published in 2002 and 1999, NREL, together with the subcontractor Harris Group Inc., performed a complete review of the process design and economic model for the biomass-to-ethanol process. This update reflects NREL's current vision of the biochemical ethanol process and includes the latest research in the conversion areas (pretreatment, conditioning, saccharification, and fermentation), optimizations in product recovery, and our latest understanding of the ethanol plant's back end (wastewater and utilities). The conceptual design presented here reports ethanol production economics as determined by 2012 conversion targets and 'nth-plant' project costs and financing. For the biorefinery described here, processing 2,205 dry ton/day at 76% theoretical ethanol yield (79 gal/dry ton), the ethanol selling price is $2.15/gal in 2007$.

  2. Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    Office of Energy Efficiency and Renewable Energy (EERE)

    This report describes one potential biochemical ethanol conversion process, conceptually based upon core conversion and process integration research at NREL. The overarching process design converts corn stover to ethanol by dilute-acid pretreatment, enzymatic saccharification, and co-fermentation. Building on design reports published in 2002 and 1999, NREL, together with the subcontractor Harris Group Inc., performed a complete review of the process design and economic model for the biomass-to-ethanol process. This update reflects NREL's current vision of the biochemical ethanol process and includes the latest research in the conversion areas (pretreatment, conditioning, saccharification, and fermentation), optimizations in product recovery, and our latest understanding of the ethanol plant's back end (wastewater and utilities). The conceptual design presented here reports ethanol production economics as determined by 2012 conversion targets and 'nth-plant' project costs and financing. For the biorefinery described here, processing 2,205 dry ton/day at 76% theoretical ethanol yield (79 gal/dry ton), the ethanol selling price is $2.15/gal in 2007$.

  3. Permanent draft genome sequence of Desulfurococcus mobilis type strain DSM 2161, a thermoacidophilic sulfur-reducing crenarchaeon isolated from acidic hot springs of Hveravellir, Iceland

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Susanti, Dwi; Johnson, Eric F.; Lapidus, Alla; Han, James; Reddy, T. B. K.; Pilay, Manoj; Ivanova, Natalia N.; Markowitz, Victor M.; Woyke, Tanja; Kyrpides, Nikos C.; et al

    2016-01-13

    Our report presents the permanent draft genome sequence of Desulfurococcus mobilis type strain DSM 2161, an obligate anaerobic hyperthermophilic crenarchaeon that was isolated from acidic hot springs in Hveravellir, Iceland. D. mobilis utilizes peptides as carbon and energy sources and reduces elemental sulfur to H2S. A metabolic construction derived from the draft genome identified putative pathways for peptide degradation and sulfur respiration in this archaeon. Existence of several hydrogenase genes in the genome supported previous findings that H2 is produced during the growth of D. mobilis in the absence of sulfur. Interestingly, genes encoding glucose transport and utilization systems alsomore » exist in the D. mobilis genome though this archaeon does not utilize carbohydrate for growth. The draft genome of D. mobilis provides an additional mean for comparative genomic analysis of desulfurococci. In addition, our analysis on the Average Nucleotide Identity between D. mobilis and Desulfurococcus mucosus suggested that these two desulfurococci are two different strains of the same species.« less

  4. Comparative Study of Corn Stover Pretreated by Dilute Acid and Cellulose Solvent-Based Lignocellulose Fractionation: Enzymatic Hydrolysis, Supramolecular Structure, and Substrate Accessibility

    SciTech Connect (OSTI)

    Zhu, Z.; Sathitsuksanoh, N.; Vinzant, T.; Schell, D. J.; McMillian, J. D.; Zhang, Y. H. P.

    2009-07-01

    Liberation of fermentable sugars from recalcitrant biomass is among the most costly steps for emerging cellulosic ethanol production. Here we compared two pretreatment methods (dilute acid, DA, and cellulose solvent and organic solvent lignocellulose fractionation, COSLIF) for corn stover. At a high cellulase loading [15 filter paper units (FPUs) or 12.3 mg cellulase per gram of glucan], glucan digestibilities of the corn stover pretreated by DA and COSLIF were 84% at hour 72 and 97% at hour 24, respectively. At a low cellulase loading (5 FPUs per gram of glucan), digestibility remained as high as 93% at hour 24 for the COSLIF-pretreated corn stover but reached only {approx}60% for the DA-pretreated biomass. Quantitative determinations of total substrate accessibility to cellulase (TSAC), cellulose accessibility to cellulase (CAC), and non-cellulose accessibility to cellulase (NCAC) based on adsorption of a non-hydrolytic recombinant protein TGC were measured for the first time. The COSLIF-pretreated corn stover had a CAC of 11.57 m{sup 2}/g, nearly twice that of the DA-pretreated biomass (5.89 m{sup 2}/g). These results, along with scanning electron microscopy images showing dramatic structural differences between the DA- and COSLIF-pretreated samples, suggest that COSLIF treatment disrupts microfibrillar structures within biomass while DA treatment mainly removes hemicellulose. Under the tested conditions COSLIF treatment breaks down lignocellulose structure more extensively than DA treatment, producing a more enzymatically reactive material with a higher CAC accompanied by faster hydrolysis rates and higher enzymatic digestibility.

  5. Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons: Dilute-Acid and Enzymatic Deconstruction of Biomass to Sugars and Catalytic Conversion of Sugars to Hydrocarbons

    SciTech Connect (OSTI)

    Davis, R.; Tao, L.; Scarlata, C.; Tan, E. C. D.; Ross, J.; Lukas, J.; Sexton, D.

    2015-03-01

    This report describes one potential conversion process to hydrocarbon products by way of catalytic conversion of lignocellulosic-derived hydrolysate. This model leverages expertise established over time in biomass deconstruction and process integration research at NREL, while adding in new technology areas for sugar purification and catalysis. The overarching process design converts biomass to die die diesel- and naphtha-range fuels using dilute-acid pretreatment, enzymatic saccharification, purifications, and catalytic conversion focused on deoxygenating and oligomerizing biomass hydrolysates.

  6. Metal-free g-C{sub 3}N{sub 4} photocatalyst by sulfuric acid activation for selective aerobic oxidation of benzyl alcohol under visible light

    SciTech Connect (OSTI)

    Zhang, Ligang; Liu, Di; Guan, Jing; Chen, Xiufang; Guo, Xingcui; Zhao, Fuhua; Hou, Tonggang; Mu, Xindong

    2014-11-15

    Highlights: A novel visible-light-driven acid-modified g-C{sub 3}N{sub 4} was prepared. The texture, electronic and surface property were tuned by acid modification. Acid-modified g-C{sub 3}N{sub 4} shows much higher activity for photocatalytic activity. Acid sites on the surface of g-C{sub 3}N{sub 4} favor efficient charge separation. - Abstract: In this work, modification of graphitic carbon nitride photocatalyst with acid was accomplished with a facile method through reflux in different acidic substances. The g-C{sub 3}N{sub 4}-based material was found to be a metal-free photocatalyst useful for the selective oxidation of benzyl alcohol with dioxygen as the oxidant under visible light irradiation. Acid modification had a significant influence on the photocatalytic performance of g-C{sub 3}N{sub 4}. Among all acid tested, sulfuric acid-modified g-C{sub 3}N{sub 4} showed the highest catalytic activity and gave benzaldehyde in 23% yield for 4 h under visible light irradiation, which was about 2.5 times higher than that of g-C{sub 3}N{sub 4}. The acid modification effectively improved surface area, reduced structural size, enlarged band gap, enhanced surface chemical state, and facilitated photoinduced charge separation, contributing to the enhanced photocatalytic activity. It is hoped that our work can open promising prospects for the utilization of metal free g-C{sub 3}N{sub 4}-based semiconductor as visible-light photocatalyst for selective organic transformation.

  7. Separation of sulfur isotopes

    DOE Patents [OSTI]

    DeWitt, Robert; Jepson, Bernhart E.; Schwind, Roger A.

    1976-06-22

    Sulfur isotopes are continuously separated and enriched using a closed loop reflux system wherein sulfur dioxide (SO.sub.2) is reacted with sodium hydroxide (NaOH) or the like to form sodium hydrogen sulfite (NaHSO.sub.3). Heavier sulfur isotopes are preferentially attracted to the NaHSO.sub.3, and subsequently reacted with sulfuric acid (H.sub.2 SO.sub.4) forming sodium hydrogen sulfate (NaHSO.sub.4) and SO.sub.2 gas which contains increased concentrations of the heavier sulfur isotopes. This heavy isotope enriched SO.sub.2 gas is subsequently separated and the NaHSO.sub.4 is reacted with NaOH to form sodium sulfate (Na.sub.2 SO.sub.4) which is subsequently decomposed in an electrodialysis unit to form the NaOH and H.sub.2 SO.sub.4 components which are used in the aforesaid reactions thereby effecting sulfur isotope separation and enrichment without objectionable loss of feed materials.

  8. Lignocellulosic Biomass to Ethanol Process Design and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis for Corn Stover

    SciTech Connect (OSTI)

    Aden, A.; Ruth, M.; Ibsen, K.; Jechura, J.; Neeves, K.; Sheehan, J.; Wallace, B.; Montague, L.; Slayton, A.; Lukas, J.

    2002-06-01

    This report is an update of NREL's ongoing process design and economic analyses of processes related to developing ethanol from lignocellulosic feedstocks. The U.S. Department of Energy (DOE) is promoting the development of ethanol from lignocellulosic feedstocks as an alternative to conventional petroleum-based transportation fuels. DOE funds both fundamental and applied research in this area and needs a method for predicting cost benefits of many research proposals. To that end, the National Renewable Energy Laboratory (NREL) has modeled many potential process designs and estimated the economics of each process during the last 20 years. This report is an update of the ongoing process design and economic analyses at NREL. We envision updating this process design report at regular intervals; the purpose being to ensure that the process design incorporates all new data from NREL research, DOE funded research and other sources, and that the equipment costs are reasonable and consistent with good engineering practice for plants of this type. For the non-research areas this means using equipment and process approaches as they are currently used in industrial applications. For the last report, published in 1999, NREL performed a complete review and update of the process design and economic model for the biomass-to-ethanol process utilizing co-current dilute acid prehydrolysis with simultaneous saccharification (enzymatic) and co-fermentation. The process design included the core technologies being researched by the DOE: prehydrolysis, simultaneous saccharification and co-fermentation, and cellulase enzyme production. In addition, all ancillary areas--feed handling, product recovery and purification, wastewater treatment (WWT), lignin combustor and boiler-turbogenerator, and utilities--were included. NREL engaged Delta-T Corporation (Delta-T) to assist in the process design evaluation, the process equipment costing, and overall plant integration. The process design and

  9. Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons: Dilute-Acid and Enzymatic Deconstruction of Biomass to Sugars and Biological Conversion of Sugars to Hydrocarbons

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

    Contract No. DE-AC36-08GO28308 Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons: Dilute-Acid and Enzymatic Deconstruction of Biomass to Sugars and Biological Conversion of Sugars to Hydrocarbons R. Davis, L. Tao, E.C.D. Tan, M.J. Biddy, G.T. Beckham, and C. Scarlata National Renewable Energy Laboratory J. Jacobson and K. Cafferty Idaho National Laboratory J. Ross, J. Lukas, D. Knorr, and P. Schoen Harris Group Inc. Technical Report NREL/TP-5100-60223

  10. Catalytic conversion of sulfur dioxide and trioxide

    SciTech Connect (OSTI)

    Solov'eva, E.L.; Shenfel'd, B.E.; Kuznetsova, S.M.; Khludenev, A.G.

    1987-11-10

    The reclamation and utilization of sulfur-containing wastes from the flue gas of fossil-fuel power plants and the subsequent reduction in sulfur emission is addressed in this paper. The authors approach this problem from the standpoint of the catalytic oxidation of sulfur dioxide on solid poison-resistant catalysts with subsequent sorption of the sulfur trioxide and its incorporation into the manufacture of sulfuric acid. The catalyst they propose is a polymetallic dust-like waste from the copper-smelting industry comprised mainly of iron and copper oxides. Experiments with this catalyst were carried out using multifactorial experiment planning.

  11. Electrochemical and metallurgical aspects of stress corrosion cracking of sensitized Alloy 600 in simulated primary water containing sulfur contamination

    SciTech Connect (OSTI)

    Bandy, R.; Kelly, K.

    1985-01-01

    The stress corrosion cracking (SCC) of sensitized Alloy 600 was investigated in aerated solutions of sodium thiosulfate containing 1.3% boric acid. Results indicate that in the borated thiosulfate solution containing 7 ppM sulfur, 5 ppM lithium as lithium hydroxide is sufficient to inhibit SCC in U-bends. The occurrence of inhibition seems to correlate to the rapid increase of pH and conductivity of the solution as a result of the lithium hydroxide addition. In the slow strain rate tests in the borated solution containing 0.7 ppM lithium as lithium hydroxide, significant SCC is observed at a sulfur level of 30 ppB, i.e., a lithium to sulfur ratio of 23. In a parallel test in 30 ppB sulfur level but without any lithium hydroxide, the SCC is more severe than that in the lithiated environment. In the constant load test on a specimen held initially at a nominal stress near the yield strength of the material, cracks continue to grow until fracture during controlled, progressive dilution of the bulk solution, leading to final lithium concentration of 1.5 ppM and sulfur concentration (as thiosulfate) of 9.6 ppB i.e., a lithium to sulfur ratio of about 156, although lithium hydroxide retards the rate of crack propagation to some extent. The crack growth rate is strongly influenced by the electrochemical potential which is primarily governed by the local crack tip chemistry.

  12. Fermentation of dilute acid pretreated Populus by Clostridium thermocellum, Caldicellulosiruptor bescii, and Caldicellulosiruptor obsidiansis

    SciTech Connect (OSTI)

    Yee, Kelsey L.; Rodriguez, Jr., Miguel; Hamilton, Choo Yieng; Hamilton-Brehm, Scott D.; Thompson, Olivia A.; Elkins, James G.; Davison, Brian H.; Mielenz, Jonathan R.

    2015-07-25

    Consolidated bioprocessing (CBP), which merges enzyme production, biomass hydrolysis, and fermentation into a single step, has the potential to become an efficient and economic strategy for the bioconversion of lignocellulosic feedstocks to transportation fuels or chemicals. In this study, we evaluated Clostridium thermocellum, Caldicellulosiruptor bescii, and Caldicellulosiruptor obsidiansis, three , thermophilic,cellulolytic, mixed-acid fermenting candidate CBP microorganisms, for their fermentation capabilities using dilute acid pretreated Populus as a model biomass feedstock. Under pH controlled, anaerobic fermentation conditions, each candidate successfully digested a minimum of 75% of the cellulose from dilute acid pretreated Populus, as indicated by an increase in planktonic cells and end-product metabolites and a concurrent decrease in glucan content. C. thermocellum, which employs a cellulosomal approach to biomass degradation, required 120 hours to achieve 75% cellulose utilization. In contrast, the non-cellulosomal, secreted hydrolytic enzyme system of the Caldicellulosiruptor sp. required 300 hours to achieve similar results. End-point fermentation conversions for C. thermocellum, C. bescii, and C. obsidiansis were determined to be 0.29, 0.34, and 0.38 grams of total metabolites per gram of loaded glucan, respectively. This data provide a starting point for future strain engineering efforts that can serve to improve the biomass fermentation capabilities of these three promising candidate CBP platforms.

  13. Graphene-sulfur nanocomposites for rechargeable lithium-sulfur...

    Office of Scientific and Technical Information (OSTI)

    Title: Graphene-sulfur nanocomposites for rechargeable lithium-sulfur battery electrodes Rechargeable lithium-sulfur batteries having a cathode that includes a graphene-sulfur ...

  14. Chemical repair of base lesions, AP-sites, and strand breaks on plasmid DNA in dilute aqueous solution by ascorbic acid

    SciTech Connect (OSTI)

    Hata, Kuniki; Advanced Science Research Center, Japan Atomic Energy Agency, 2-4 Shirakatashirane, Tokai-mura, Naka-gun, Ibaraki 319-1195 ; Urushibara, Ayumi; Yamashita, Shinichi; Shikazono, Naoya; Yokoya, Akinari; Katsumura, Yosuke; Nuclear Professional School, School of Engineering, The University of Tokyo, 2-22 Shirakatashirane, Tokai-mura, Naka-gun, Ibaraki 319-1188

    2013-05-03

    Highlights: We report a novel mechanism of radiation protection of DNA by chemical activity of ascorbic acid. The chemical repair of DNA damage was revealed using biochemical assay and chemical kinetics analysis. We found that ascorbic acid significantly repairs precursors of nucleobase lesions and abasic sites. However, ascorbic acid seldom repairs precursors of DNA-strand breaks. -- Abstract: We quantified the damage yields produced in plasmid DNA by ?-irradiation in the presence of low concentrations (10100 ?M) of ascorbic acid, which is a major antioxidant in living systems, to clarify whether it chemically repairs radiation damage in DNA. The yield of DNA single strand breaks induced by irradiation was analyzed with agarose gel electrophoresis as conformational changes in closed circular plasmids. Base lesions and abasic sites were also observed as additional conformational changes by treating irradiated samples with glycosylase proteins. By comparing the suppression efficiencies to the induction of each DNA lesion, in addition to scavenging of the OH radicals derived from water radiolysis, it was found that ascorbic acid promotes the chemical repair of precursors of AP-sites and base lesions more effectively than those of single strand breaks. We estimated the efficiency of the chemical repair of each lesion using a kinetic model. Approximately 5060% of base lesions and AP-sites were repaired by 10 ?M ascorbic acid, although strand breaks were largely unrepaired by ascorbic acid at low concentrations. The methods in this study will provide a route to understanding the mechanistic aspects of antioxidant activity in living systems.

  15. Helium dilution refrigeration system

    DOE Patents [OSTI]

    Roach, P.R.; Gray, K.E.

    1988-09-13

    A helium dilution refrigeration system operable over a limited time period, and recyclable for a next period of operation is disclosed. The refrigeration system is compact with a self-contained pumping system and heaters for operation of the system. A mixing chamber contains [sup 3]He and [sup 4]He liquids which are precooled by a coupled container containing [sup 3]He liquid, enabling the phase separation of a [sup 3]He rich liquid phase from a dilute [sup 3]He-[sup 4]He liquid phase which leads to the final stage of a dilution cooling process for obtaining low temperatures. The mixing chamber and a still are coupled by a fluid line and are maintained at substantially the same level with the still cross sectional area being smaller than that of the mixing chamber. This configuration provides maximum cooling power and efficiency by the cooling period ending when the [sup 3]He liquid is depleted from the mixing chamber with the mixing chamber nearly empty of liquid helium, thus avoiding unnecessary and inefficient cooling of a large amount of the dilute [sup 3]He-[sup 4]He liquid phase. 2 figs.

  16. Helium dilution refrigeration system

    DOE Patents [OSTI]

    Roach, Patrick R.; Gray, Kenneth E.

    1988-01-01

    A helium dilution refrigeration system operable over a limited time period, and recyclable for a next period of operation. The refrigeration system is compact with a self-contained pumping system and heaters for operation of the system. A mixing chamber contains .sup.3 He and .sup.4 He liquids which are precooled by a coupled container containing .sup.3 He liquid, enabling the phase separation of a .sup.3 He rich liquid phase from a dilute .sup.3 He-.sup.4 He liquid phase which leads to the final stage of a dilution cooling process for obtaining low temperatures. The mixing chamber and a still are coupled by a fluid line and are maintained at substantially the same level with the still cross sectional area being smaller than that of the mixing chamber. This configuration provides maximum cooling power and efficiency by the cooling period ending when the .sup.3 He liquid is depleted from the mixing chamber with the mixing chamber nearly empty of liquid helium, thus avoiding unnecessary and inefficient cooling of a large amount of the dilute .sup.3 He-.sup.4 He liquid phase.

  17. Biodiesel Impact on Engine Lubricant Dilution During Active Regeneration of Aftertreatment Systems

    SciTech Connect (OSTI)

    He, X.; Williams, A.; Christensen, E.; Burton, J.; McCormick, R.

    2011-12-01

    Experiments were conducted with ultra low sulfur diesel (ULSD) and 20% biodiesel blends (B20) to compare lube oil dilution levels and lubricant properties for systems using late in-cylinder fuel injection for aftertreatment regeneration. Lube oil dilution was measured by gas chromatography (GC) following ASTM method D3524 to measure diesel content, by Fourier transform infrared (FTIR) spectrometry following a modified ASTM method D7371 to measure biodiesel content, and by a newly developed back-flush GC method that simultaneously measures both diesel and biodiesel. Heavy-duty (HD) engine testing was conducted on a 2008 6.7L Cummins ISB equipped with a diesel oxidation catalyst (DOC) and diesel particle filter (DPF). Stage one of engine testing consisted of 10 consecutive repeats of a forced DPF regeneration event. This continuous operation with late in-cylinder fuel injection served as a method to accelerate lube-oil dilution. Stage two consisted of 16 hours of normal engine operation over a transient test cycle, which created an opportunity for any accumulated fuel in the oil sump to evaporate. Light duty (LD) vehicle testing was conducted on a 2010 VW Jetta equipped with DOC, DPF and a NOx storage catalyst (NSC). Vehicle testing comprised approximately 4,000 miles of operation on a mileage-accumulation dynamometer (MAD) using the U.S. Environmental Protection Agency's Highway Fuel Economy Cycle because of the relatively low engine oil and exhaust temperatures, and high DPF regeneration frequency of this cycle relative to other cycles examined. Comparison of the lube oil dilution analysis methods suggests that D3524 does not measure dilution by biodiesel. The new back-flush GC method provided analysis for both diesel and biodiesel, in a shorter time and with lower detection limit. Thus all lube oil dilution results in this paper are based on this method. Analysis of the HD lube-oil samples showed only 1.5% to 1.6% fuel dilution for both fuels during continuous

  18. Uses of lunar sulfur

    SciTech Connect (OSTI)

    Vaniman, D.T.; Pettit, D.R.; Heiken, G.

    1988-01-01

    Sulfur and sulfur compounds have a wide range of applications for their fluid, electrical, chemical and biochemical properties. Although low in abundance on the Moon (/approximately/0.1% in mare soils), sulfur is surface-correlated and relatively extractable. Co-production of sulfur during oxygen extraction from ilmenite-rich soils could yield sulfur in masses up to 10% of the mass of oxygen produced. Sulfur deserves serious consideration as a lunar resource. 29 refs., 3 figs.

  19. Improving a recombinant Zymomonas mobilis strain 8b through continuous adaptation on dilute acid pretreated corn stover hydrolysate

    SciTech Connect (OSTI)

    Mohagheghi, Ali; Linger, Jeffrey G.; Yang, Shihui; Smith, Holly; Dowe, Nancy; Zhang, Min; Pienkos, Philip T.

    2015-03-31

    Complete conversion of the major sugars of biomass including both the C5 and C6 sugars is critical for biofuel production processes. Several inhibitory compounds like acetate, hydroxymethylfurfural (HMF), and furfural are produced from the biomass pretreatment process leading to ‘hydrolysate toxicity,’ a major problem for microorganisms to achieve complete sugar utilization. Therefore, development of more robust microorganisms to utilize the sugars released from biomass under toxic environment is critical. In this study, we use continuous culture methodologies to evolve and adapt the ethanologenic bacterium Zymomonas mobilis to improve its ethanol productivity using corn stover hydrolysate. The results are the following: A turbidostat was used to adapt the Z. mobilis strain 8b in the pretreated corn stover liquor. The adaptation was initiated using pure sugar (glucose and xylose) followed by feeding neutralized liquor at different dilution rates. Once the turbidostat reached 60% liquor content, the cells began washing out and the adaptation was stopped. Several ‘sub-strains’ were isolated, and one of them, SS3 (sub-strain 3), had 59% higher xylose utilization than the parent strain 8b when evaluated on 55% neutralized PCS (pretreated corn stover) liquor. Using saccharified PCS slurry generated by enzymatic hydrolysis from 25% solids loading, SS3 generated an ethanol yield of 75.5% compared to 64% for parent strain 8b. Furthermore, the total xylose utilization was 57.7% for SS3 versus 27.4% for strain 8b. To determine the underlying genotypes in these new sub-strains, we conducted genomic resequencing and identified numerous single-nucleotide mutations (SNPs) that had arisen in SS3. We further performed quantitative reverse transcription PCR (qRT-PCR) on genes potentially affected by these SNPs and identified significant down-regulation of two genes, ZMO0153 and ZMO0776, in SS3 suggesting potential genetic mechanisms behind SS3

  20. CATALYST EVALUATION FOR A SULFUR DIOXIDE-DEPOLARIZED ELECTROLYZER

    SciTech Connect (OSTI)

    Hobbs, D; Hector Colon-Mercado, H

    2007-01-31

    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.

  1. CRADA Final Report For CRADA NO. CR-12-006 [Operation and Testing of an SO{sub 2}-depolarized Electrolyzer (SDE) for the Purpose of Hydrogen and Sulfuric Acid Production

    SciTech Connect (OSTI)

    Summers, W. A.; Colon-Mercado, H. R.; Steimke, J. L.; Zahn, Steffen

    2014-02-24

    Over the past several years, Savannah River National Laboratory (SRNL) has led a team of collaborators under the Department of Energy’s (DOE) nuclear hydrogen production program to develop the Hybrid Sulfur (HyS) Process. HyS is a 2-step water-splitting process consisting of high temperature decomposition of sulfuric acid to generate SO{sub 2}, followed by the electrolysis of aqueous SO{sub 2} to generate hydrogen and sulfuric acid. The latter is fed back into the high temperature reactor. SRNL designed and built an SO{sub 2}-depolarized electrolyzer (SDE) and a test facility. Over 40 SDE’s were tested using different catalysts, membranes and other components. SRNL demonstrated that an SDE could be operated continuously for approximately 200 hours under certain conditions without buildup of sulfur at the SDE’s cathode, thus solving a key technical problem with SDE technology. Air Products and Chemicals, Inc. (APCI) is a major supplier of hydrogen production systems, and they have proprietary technology that could benefit from the SDE developed by SRNS, or some improved version thereof. However, to demonstrate that SRNL’s SDE is a truly viable approach to the electrolyzer design, continuous operation for far greater periods of time than 200 hours must be demonstrated, and the electrolyzer must be scaled up to greater hydrogen production capacities. SRNL and Air Products entered into a Cooperative Research and Development Agreement with the objective of demonstrating the effectiveness of the SDE for hydrogen and sulfuric acid production and to demonstrate long-term continuous operation so as to dramatically increase the confidence in the SDE design for commercial operation. SRNL prepared a detailed technical report documenting previous SDE development, including the current SDE design and operating conditions that led to the 200-hour sulfurfree testing. SRNL refurbished its single cell SDE test facility and qualified the equipment for continuous operation. A

  2. Can Delignification Decrease Cellulose Digestibility in Acid Pretreated Corn Stover?

    SciTech Connect (OSTI)

    Ishizawa, C. I.; Jeoh, T.; Adney, W. S.; Himmel, M. E.; Johnson, D. K.; Davis, M. F.

    2009-01-01

    It has previously been shown that the improved digestibility of dilute acid pretreated corn stover is at least partially due to the removal of xylan and the consequent increase in accessibility of the cellulose to cellobiohydrolase enzymes. We now report on the impact that lignin removal has on the accessibility and digestibility of dilute acid pretreated corn stover. Samples of corn stover were subjected to dilute sulfuric acid pretreatment with and without simultaneous (partial) lignin removal. In addition, some samples were completely delignified after the pretreatment step using acidified sodium chlorite. The accessibility and digestibility of the samples were tested using a fluorescence-labeled cellobiohydrolase (Trichoderma reesei Cel7A) purified from a commercial cellulase preparation. Partial delignification of corn stover during dilute acid pretreatment was shown to improve cellulose digestibility by T. reesei Cel7A; however, decreasing the lignin content below 5% (g g{sup -1}) by treatment with acidified sodium chlorite resulted in a dramatic reduction in cellulose digestibility. Importantly, this effect was found to be enhanced in samples with lower xylan contents suggesting that the near complete removal of xylan and lignin may cause aggregation of the cellulose microfibrils resulting in decreased cellulase accessibility.

  3. In situ Observation of Sulfur in Living Mammalian Cells: Uptake of Taurine

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

    into MDCK Cells In situ Observation of Sulfur in Living Mammalian Cells: Uptake of Taurine into MDCK Cells Sulfur is essential for life. It plays important roles in the amino acids methionine and cysteine, and has a structural function in disulfide bonds. As a component of iron-sulfur clusters it takes part in electron and sulfur transfer reactions.1 Glutathione, a sulfur-containing tripeptide, is an important part of biological antioxidant systems.2 Another example for the biological

  4. Sulfur recovery process

    SciTech Connect (OSTI)

    Hise, R.E.; Cook, W.J.

    1991-06-04

    This paper describes a method for recovering sulfur from a process feed stream mixture of gases comprising sulfur-containing compounds including hydrogen sulfide using the Claus reaction to convert sulfur-containing compounds to elemental sulfur and crystallization to separate sulfur-containing compounds from a tail gas of the Claus reaction for further processing as a recycle stream. It comprises: providing a Claus feed stream containing a stoichiometric excess of hydrogen sulfide, the Claus feed stream including the process feed stream and the recycles stream; introducing the Claus feed stream and an oxidizing agent into a sulfur recovery unit for converting sulfur-containing compounds in the Claus feed stream to elemental sulfur; withdrawing the tail gas from the sulfur recovery unit; separating water from the tail gas to producing a dehydrated tail gas; separating sulfur-containing compounds including carbonyl sulfide from the dehydrated tail gas as an excluded material by crystallization and withdrawing an excluded material-enriched output from the crystallization to produce the recycle stream; and combining the recycle stream with the process feed stream to produce the Claus feed stream.

  5. Membranes for the Sulfur-Iodine Integrated Laboratory Scale Demonstration

    SciTech Connect (OSTI)

    Frederick F. Stewart

    2007-08-01

    INL has developed polymeric membrane-based chemical separations to enable the thermochemical production of hydrogen. Major activities included studies of sulfuric acid concentration membranes, hydriodic acid concentration membranes, SO2/O2 separation membranes, potential applications of a catalyst reactor system for the decomposition of HI, and evaluation of the chemical separation needs for alternate thermochemical cycles. Membranes for the concentration of sulfuric acid were studied using pervaporation. The goal of this task was to offer the sulfur-iodine (S-I) and the hybrid sulfur (HyS) cycles a method to concentrate the sulfuric acid containing effluent from the decomposer without boiling. In this work, sulfuric acid decomposer effluent needs to be concentrated from ~50 % acid to 80 %. This task continued FY 2006 efforts to characterize water selective membranes for use in sulfuric acid concentration. In FY 2007, experiments were conducted to provide specific information, including transmembrane fluxes, separation factors, and membrane durability, necessary for proper decision making on the potential inclusion of this process into the S-I or HyS Integrated Laboratory Scale demonstration.

  6. Future Sulfur Dioxide Emissions

    SciTech Connect (OSTI)

    Smith, Steven J.; Pitcher, Hugh M.; Wigley, Tom M.

    2005-12-01

    The importance of sulfur dioxide emissions for climate change is now established, although substantial uncertainties remain. This paper presents projections for future sulfur dioxide emissions using the MiniCAM integrated assessment model. A new income-based parameterization for future sulfur dioxide emissions controls is developed based on purchasing power parity (PPP) income estimates and historical trends related to the implementation of sulfur emissions limitations. This parameterization is then used to produce sulfur dioxide emissions trajectories for the set of scenarios developed for the Special Report on Emission Scenarios (SRES). We use the SRES methodology to produce harmonized SRES scenarios using the latest version of the MiniCAM model. The implications, and requirements, for IA modeling of sulfur dioxide emissions are discussed. We find that sulfur emissions eventually decline over the next century under a wide set of assumptions. These emission reductions result from a combination of emission controls, the adoption of advanced electric technologies, and a shift away from the direct end use of coal with increasing income levels. Only under a scenario where incomes in developing regions increase slowly do global emission levels remain at close to present levels over the next century. Under a climate policy that limits emissions of carbon dioxide, sulfur dioxide emissions fall in a relatively narrow range. In all cases, the relative climatic effect of sulfur dioxide emissions decreases dramatically to a point where sulfur dioxide is only a minor component of climate forcing by the end of the century. Ecological effects of sulfur dioxide, however, could be significant in some developing regions for many decades to come.

  7. Elemental sulfur recovery process

    DOE Patents [OSTI]

    Flytzani-Stephanopoulos, Maria; Hu, Zhicheng

    1993-01-01

    An improved catalytic reduction process for the direct recovery of elemental sulfur from various SO.sub.2 -containing industrial gas streams. The catalytic process provides combined high activity and selectivity 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 certain catalyst formulations based on cerium oxide. The process is a single-stage, catalytic sulfur recovery process in conjunction with regenerators, such as those used in dry, regenerative flue gas desulfurization or other processes, involving direct reduction of the SO.sub.2 in the regenerator off gas stream to elemental sulfur in the presence of a catalyst.

  8. Elemental sulfur recovery process

    DOE Patents [OSTI]

    Flytzani-Stephanopoulos, M.; Zhicheng Hu.

    1993-09-07

    An improved catalytic reduction process for the direct recovery of elemental sulfur from various SO[sub 2]-containing industrial gas streams. The catalytic process provides combined high activity and selectivity 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 certain catalyst formulations based on cerium oxide. The process is a single-stage, catalytic sulfur recovery process in conjunction with regenerators, such as those used in dry, regenerative flue gas desulfurization or other processes, involving direct reduction of the SO[sub 2] in the regenerator off gas stream to elemental sulfur in the presence of a catalyst. 4 figures.

  9. Synthesis and development of processes for the recovery of sulfur from acid gases. Part 1, Development of a high-temperature process for removal of H{sub 2}S from coal gas using limestone -- thermodynamic and kinetic considerations; Part 2, Development of a zero-emissions process for recovery of sulfur from acid gas streams

    SciTech Connect (OSTI)

    Towler, G.P.; Lynn, S.

    1993-05-01

    Limestone can be used more effectively as a sorbent for H{sub 2}S in high-temperature gas-cleaning applications if it is prevented from undergoing calcination. Sorption of H{sub 2}S by limestone is impeded by sintering of the product CaS layer. Sintering of CaS is catalyzed by CO{sub 2}, but is not affected by N{sub 2} or H{sub 2}. The kinetics of CaS sintering was determined for the temperature range 750--900{degrees}C. When hydrogen sulfide is heated above 600{degrees}C in the presence of carbon dioxide elemental sulfur is formed. The rate-limiting step of elemental sulfur formation is thermal decomposition of H{sub 2}S. Part of the hydrogen thereby produced reacts with CO{sub 2}, forming CO via the water-gas-shift reaction. The equilibrium of H{sub 2}S decomposition is therefore shifted to favor the formation of elemental sulfur. The main byproduct is COS, formed by a reaction between CO{sub 2} and H{sub 2}S that is analogous to the water-gas-shift reaction. Smaller amounts of SO{sub 2} and CS{sub 2} also form. Molybdenum disulfide is a strong catalyst for H{sub 2}S decomposition in the presence of CO{sub 2}. A process for recovery of sulfur from H{sub 2}S using this chemistry is as follows: Hydrogen sulfide is heated in a high-temperature reactor in the presence of CO{sub 2} and a suitable catalyst. The primary products of the overall reaction are S{sub 2}, CO, H{sub 2} and H{sub 2}O. Rapid quenching of the reaction mixture to roughly 600{degrees}C prevents loss Of S{sub 2} during cooling. Carbonyl sulfide is removed from the product gas by hydrolysis back to CO{sub 2} and H{sub 2}S. Unreacted CO{sub 2} and H{sub 2}S are removed from the product gas and recycled to the reactor, leaving a gas consisting chiefly of H{sub 2} and CO, which recovers the hydrogen value from the H{sub 2}S. This process is economically favorable compared to the existing sulfur-recovery technology and allows emissions of sulfur-containing gases to be controlled to very low levels.

  10. Biogenic sulfur source strengths

    SciTech Connect (OSTI)

    Adams, D.F.; Farwell, S.O.; Robinson, E.; Pack, M.R.; Bamesberger, W.L.

    1981-12-01

    Conclusions are presented from a 4-yr field measurement study of biogenic sulfur gas emissions from soils, and some water and vegetated surfaces, at 35 locales in the eastern and southeastern United States. More than one soil order was examined whenever possible to increase the data base obtained from the 11 major soil orders comprising the study area. Data analysis and emission model development were based upon an (80 x 80)-km/sup 2/ grid system. The measured sulfur fluxes, adjusted for the annual mean temperature for each sampling locale, weigted by the percentage of each soil order within each grid, and averaged for each of the east-west grid tiers from 47/sup 0/N to 25/sup 0/N latitude, showed an exponential north-to-south increase in total sulfur gas flux. Our model predits an additional increase of nearly 25-fold in sulfur flux between 25/sup 0/N and the equator.

  11. Bacterial Sulfur Storage Globules

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

    Prominent among these are the sulfide-oxidizing bacteria that oxidize sulfide (S2-) to sulfate (SO42-). Many of these organisms can store elemental sulfur (S0) in "globules" for...

  12. The adsorption of gold, palladium and platinum from acidic chloride solutions on mesoporous carbons.

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zalupski, Peter R.; McDowell, Rocklan; Dutech, Guy

    2014-08-05

    Studies on the adsorption characteristics of gold, palladium and platinum on mesoporous carbon (CMK-3) and sulfur-impregnated mesoporous carbon (CMK-3/S) evaluated the benefits/drawbacks of the presence of a layer of elemental sulfur inside mesoporous carbon structures. Adsorption isotherms collected for Au(III), Pd(II) and Pt(IV) on those materials suggest that sulfur does enhance the adsorption of those metal ions in mildly acidic environment (pH 3). The isotherms collected in 1 M HCl show that the benefit of sulfur disappears due to the competing influence of large concentration of hydrogen ions on the ion-exchanging mechanism of metal ions sorption on mesoporous carbon surfaces.more » The collected acid dependencies illustrate similar adsorption characteristics for CMK-3 and CMK-3/S in 1-5 M HCl concentration range. Sorption of metal ions from diluted aqueous acidic mixtures of actual leached electronic waste demonstrated the feasibility of recovery of gold from such liquors.« less

  13. The adsorption of gold, palladium and platinum from acidic chloride solutions on mesoporous carbons.

    SciTech Connect (OSTI)

    Zalupski, Peter R.; McDowell, Rocklan; Dutech, Guy

    2014-08-05

    Studies on the adsorption characteristics of gold, palladium and platinum on mesoporous carbon (CMK-3) and sulfur-impregnated mesoporous carbon (CMK-3/S) evaluated the benefits/drawbacks of the presence of a layer of elemental sulfur inside mesoporous carbon structures. Adsorption isotherms collected for Au(III), Pd(II) and Pt(IV) on those materials suggest that sulfur does enhance the adsorption of those metal ions in mildly acidic environment (pH 3). The isotherms collected in 1 M HCl show that the benefit of sulfur disappears due to the competing influence of large concentration of hydrogen ions on the ion-exchanging mechanism of metal ions sorption on mesoporous carbon surfaces. The collected acid dependencies illustrate similar adsorption characteristics for CMK-3 and CMK-3/S in 1-5 M HCl concentration range. Sorption of metal ions from diluted aqueous acidic mixtures of actual leached electronic waste demonstrated the feasibility of recovery of gold from such liquors.

  14. The adsorption of gold, palladium and platinum from acidic chloride solutions on mesoporous carbons.

    SciTech Connect (OSTI)

    Peter Zalupski; Rocklan McDowell; Guy Dutech

    2014-10-01

    Studies on the adsorption characteristics of gold, palladium and platinum on mesoporous carbon (CMK-3) and sulfur-impregnated mesoporous carbon (CMK-3/S) evaluated the benefits/drawbacks of the presence of a layer of elemental sulfur inside mesoporous carbon structures. Adsorption isotherms collected for Au(III), Pd(II) and Pt(IV) on those materials suggest that sulfur does enhance the adsorption of those metal ions in mildly acidic environment (pH 3). The isotherms collected in 1 M HCl show that the benefit of sulfur disappears due to the competing influence of large concentration of hydrogen ions on the ion-exchanging mechanism of metal ions sorption on mesoporous carbon surfaces. The collected acid dependencies illustrate similar adsorption characteristics for CMK-3 and CMK-3/S in 1-5 M HCl concentration range. Sorption of metal ions from diluted aqueous acidic mixtures of actual leached electronic waste demonstrated the feasibility of recovery of gold from such liquors.

  15. Acid soluble, pepsin resistant platelet aggregating material

    DOE Patents [OSTI]

    Schneider, Morris D.

    1982-08-31

    Acid soluble, pepsin resistant, platelet aggregating material isolated from equine arterial tissue by extraction with dilute aqueous acid, method of isolation and use to control bleeding.

  16. Sodium-sulfur thermal battery

    SciTech Connect (OSTI)

    Ludwig, F.A.

    1990-12-11

    This paper discusses a sodium-sulfur thermal battery for generating electrical energy at temperatures above the melting point of sodium metal and sulfur. It comprises a sodium electrode comprising sodium metal; a sulfur electrode comprising sulfur; and a separator located between the sodium and sulfur electrodes. The separator having sufficient porosity to allow preliminary migration of fluid sodium metal and fluid sulfur and fluid sodium polysulfides therethrough during operation of the thermal battery to form a mixed polysulfides electrolyte gradient within the separator.

  17. Sodium sulfur battery seal

    DOE Patents [OSTI]

    Mikkor, Mati

    1981-01-01

    This disclosure is directed to an improvement in a sodium sulfur battery construction in which a seal between various battery compartments is made by a structure in which a soft metal seal member is held in a sealing position by holding structure. A pressure applying structure is used to apply pressure on the soft metal seal member when it is being held in sealing relationship to a surface of a container member of the sodium sulfur battery by the holding structure. The improvement comprises including a thin, well-adhered, soft metal layer on the surface of the container member of the sodium sulfur battery to which the soft metal seal member is to be bonded.

  18. Catalyst for the reduction of sulfur dioxide to elemental sulfur

    DOE Patents [OSTI]

    Jin, Yun; Yu, Qiquan; Chang, Shih-Ger

    1996-01-01

    The inventive catalysts allow for the reduction of sulfur dioxide to elemental sulfur in smokestack scrubber environments. The catalysts have a very high sulfur yield of over 90% and space velocity of 10,000 h.sup.-1. They also have the capacity to convert waste gases generated during the initial conversion into elemental sulfur. The catalysts have inexpensive components, and are inexpensive to produce. The net impact of the invention is to make this technology practically available to industrial applications.

  19. Sulfur Based Thermochemical Heat Storage for Baseload Concentrated Solar Power Generation

    SciTech Connect (OSTI)

    wong, bunsen

    2014-11-20

    This project investigates the engineering and economic feasibility of supplying baseload power using a concentrating solar power (CSP) plant integrated with sulfur based thermochemical heat storage. The technology stores high temperature solar heat in the chemical bonds of elemental sulfur. Energy is recovered as high temperature heat upon sulfur combustion. Extensive developmental and design work associated with sulfur dioxide (SO2) disproportionation and sulfuric acid (H2SO4) decomposition chemical reactions used in this technology had been carried out in the two completed phases of this project. The feasibility and economics of the proposed concept was demonstrated and determined.

  20. Sodium sulfur battery seal

    DOE Patents [OSTI]

    Topouzian, Armenag

    1980-01-01

    This invention is directed to a seal for a sodium sulfur battery in which a flexible diaphragm sealing elements respectively engage opposite sides of a ceramic component of the battery which separates an anode compartment from a cathode compartment of the battery.

  1. SULFUR POLYMER ENCAPSULATION.

    SciTech Connect (OSTI)

    KALB, P.

    2001-08-22

    Sulfur polymer cement (SPC) is a thermoplastic polymer consisting of 95 wt% elemental sulfur and 5 wt% organic modifiers to enhance long-term durability. SPC was originally developed by the U.S. Bureau of Mines as an alternative to hydraulic cement for construction applications. Previous attempts to use elemental sulfur as a construction material in the chemical industry failed due to premature degradation. These failures were caused by the internal stresses that result from changes in crystalline structure upon cooling of the material. By reacting elemental sulfur with organic polymers, the Bureau of Mines developed a product that successfully suppresses the solid phase transition and significantly improves the stability of the product. SPC, originally named modified sulfur cement, is produced from readily available, inexpensive waste sulfur derived from desulfurization of both flue gases and petroleum. The commercial production of SPC is licensed in the United States by Martin Resources (Odessa, Texas) and is marketed under the trade name Chement 2000. It is sold in granular form and is relatively inexpensive ({approx}$0.10 to 0.12/lb). Application of SPC for the treatment of radioactive, hazardous, and mixed wastes was initially developed and patented by Brookhaven National Laboratory (BNL) in the mid-1980s (Kalb and Colombo, 1985; Colombo et al., 1997). The process was subsequently investigated by the Commission of the European Communities (Van Dalen and Rijpkema, 1989), Idaho National Engineering Laboratory (Darnell, 1991), and Oak Ridge National Laboratory (Mattus and Mattus, 1994). SPC has been used primarily in microencapsulation applications but can also be used for macroencapsulation of waste. SPC microencapsulation has been demonstrated to be an effective treatment for a wide variety of wastes, including incinerator hearth and fly ash; aqueous concentrates such as sulfates, borates, and chlorides; blowdown solutions; soils; and sludges. It is not

  2. RECENT ADVANCES IN THE DEVELOPMENT OF THE HYBRID SULFUR PROCESS FOR HYDROGEN PRODUCTION

    SciTech Connect (OSTI)

    Hobbs, D.

    2010-07-22

    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. In the HyS Process, sulfur dioxide is oxidized in the presence of water at the electrolyzer anode to produce sulfuric acid and protons. The protons are transported through a cation-exchange membrane electrolyte to the cathode and are reduced to form hydrogen. In the second stage of the process, the sulfuric acid by-product from the electrolyzer is thermally decomposed at high temperature to produce sulfur dioxide and oxygen. The two gases are separated and the sulfur dioxide recycled to the electrolyzer for oxidation. The Savannah River National Laboratory (SRNL) has been exploring a fuel-cell design concept for the SDE using an anolyte feed comprised of concentrated sulfuric acid saturated with sulfur dioxide. The advantages of this design concept include high electrochemical efficiency and small footprint compared to a parallel-plate electrolyzer design. This paper will provide a summary of recent advances in the development of the SDE for the HyS process.

  3. Band anticrossing in dilute nitrides

    SciTech Connect (OSTI)

    Shan, W.; Yu, K.M.; Walukiewicz, W.; Wu, J.; Ager III, J.W.; Haller, E.E.

    2003-12-23

    Alloying III-V compounds with small amounts of nitrogen leads to dramatic reduction of the fundamental band-gap energy in the resulting dilute nitride alloys. The effect originates from an anti-crossing interaction between the extended conduction-band states and localized N states. The interaction splits the conduction band into two nonparabolic subbands. The downward shift of the lower conduction subband edge is responsible for the N-induced reduction of the fundamental band-gap energy. The changes in the conduction band structure result in significant increase in electron effective mass and decrease in the electron mobility, and lead to a large enhance of the maximum doping level in GaInNAs doped with group VI donors. In addition, a striking asymmetry in the electrical activation of group IV and group VI donors can be attributed to mutual passivation process through formation of the nearest neighbor group-IV donor nitrogen pairs.

  4. Biodiesel Impact on Engine Lubricant Oil Dilution

    Broader source: Energy.gov [DOE]

    Heavy-duty engine and light-duty vehicle experiments were conducted to investigate the potential for lubricant dilution by fuel during DPF regeneration events.

  5. METHOD TO PREVENT SULFUR ACCUMULATION INSIDE MEMBRANE ELECTRODE ASSEMBLY

    SciTech Connect (OSTI)

    Steimke, J.; Steeper, T.; Herman, D.; Colon-Mercado, H.; Elvington, M.

    2009-06-22

    HyS is conceptually the simplest of the thermochemical cycles and involves only sulfur chemistry. In the HyS Cycle hydrogen gas (H{sub 2}) is produced at the cathode of the electrochemical cell (or electrolyzer). Sulfur dioxide (SO{sub 2}) is oxidized at the anode to form sulfuric acid (H{sub 2}SO{sub 4}) and protons (H{sup +}) as illustrated below. A separate high temperature reaction decomposes the sulfuric acid to water and sulfur dioxide which are recycled to the electrolyzers, and oxygen which is separated out as a secondary product. The electrolyzer includes a membrane that will allow hydrogen ions to pass through but block the flow of hydrogen gas. The membrane is also intended to prevent other chemical species from migrating between electrodes and undergoing undesired reactions that could poison the cathode or reduce overall process efficiency. In conventional water electrolysis, water is oxidized at the anode to produce protons and oxygen. The standard cell potential for conventional water electrolysis is 1.23 volts at 25 C. However, commercial electrolyzers typically require higher voltages ranging from 1.8 V to 2.6 V [Kirk-Othmer, 1991]. The oxidation of sulfur dioxide instead of water in the HyS electrolyzer occurs at a much lower potential. For example, the standard cell potential for sulfur dioxide oxidation at 25 C in 50 wt % sulfuric acid is 0.29 V [Westinghouse, 1980]. Since power consumption by the electrolyzers is equal to voltage times current, and current is proportional to hydrogen production, a large reduction in voltage results in a large reduction in electrical power cost per unit of hydrogen generated.

  6. Catalyst for the reduction of sulfur dioxide to elemental sulfur

    DOE Patents [OSTI]

    Jin, Y.; Yu, Q.; Chang, S.G.

    1996-02-27

    The inventive catalysts allow for the reduction of sulfur dioxide to elemental sulfur in smokestack scrubber environments. The catalysts have a very high sulfur yield of over 90% and space velocity of 10,000 h{sup {minus}1}. They also have the capacity to convert waste gases generated during the initial conversion into elemental sulfur. The catalysts have inexpensive components, and are inexpensive to produce. The net impact of the invention is to make this technology practically available to industrial applications. 21 figs.

  7. Sulfur@Carbon Cathodes for Lithium Sulfur Batteries > Research...

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

    for Lithium Sulfur Batteries Better Ham & Cheese: Enhanced Anodes and Cathodes for Fuel Cells Epitaxial Single Crystal Nanostructures for Batteries & PVs High Performance ...

  8. Acid soluble platelet aggregating material isolated from human umbilical cord

    DOE Patents [OSTI]

    Schneider, Morris D.

    1983-01-01

    Acid soluble, pepsin sensitive platelet aggregating material isolated from human umbilical cord tissue by extraction with dilute aqueous acid, method of isolation and use to control bleeding.

  9. Evaluation of Sulfur in Syngas

    SciTech Connect (OSTI)

    None

    2006-04-01

    This project will define the options and costs at different scales of technology that can be used to remove sulfur from syngas.

  10. Method of removing and recovering elemental sulfur from highly reducing gas streams containing sulfur gases

    DOE Patents [OSTI]

    Gangwal, Santosh K.; Nikolopoulos, Apostolos A.; Dorchak, Thomas P.; Dorchak, Mary Anne

    2005-11-08

    A method is provided for removal of sulfur gases and recovery of elemental sulfur from sulfur gas containing supply streams, such as syngas or coal gas, by contacting the supply stream with a catalyst, that is either an activated carbon or an oxide based catalyst, and an oxidant, such as sulfur dioxide, in a reaction medium such as molten sulfur, to convert the sulfur gases in the supply stream to elemental sulfur, and recovering the elemental sulfur by separation from the reaction medium.

  11. Process for removing sulfur from sulfur-containing gases

    DOE Patents [OSTI]

    Rochelle, Gary T.; Jozewicz, Wojciech

    1989-01-01

    The present disclosure relates to improved processes for treating hot sulfur-containing flue gas to remove sulfur therefrom. Processes in accorda The government may own certain rights in the present invention pursuant to EPA Cooperative Agreement CR 81-1531.

  12. Volume efficient sodium sulfur battery

    DOE Patents [OSTI]

    Mikkor, Mati

    1980-01-01

    In accordance with the teachings of this specification, a sodium sulfur battery is formed as follows. A plurality of box shaped sulfur electrodes are provided, the outer surfaces of which are defined by an electrolyte material. Each of the electrodes have length and width dimensions substantially greater than the thicknesses thereof as well as upwardly facing surface and a downwardly facing surface. An electrode structure is contained in each of the sulfur electrodes. A holding structure is provided for holding the plurality of sulfur electrodes in a stacked condition with the upwardly facing surface of one sulfur electrode in facing relationship to the downwardly facing surface of another sulfur electrode thereabove. A small thickness dimension separates each of the stacked electrodes thereby defining between each pair of sulfur electrodes a volume which receives the sodium reactant. A reservoir is provided for containing sodium. A manifold structure interconnects the volumes between the sulfur electrodes and the reservoir. A metering structure controls the flow of sodium between the reservoir and the manifold structure.

  13. Sodium-tetravalent sulfur molten chloroaluminate cell

    DOE Patents [OSTI]

    Mamantov, Gleb (Knoxville, TN)

    1985-04-02

    A sodium-tetravalent sulfur molten chloroaluminate cell with a .beta."-alumina sodium ion conductor having a S-Al mole ratio of above about 0.15 in an acidic molten chloroaluminate cathode composition is disclosed. The cathode composition has an AlCl.sub.3 -NaCl mole percent ratio of above about 70-30 at theoretical full charge. The cell provides high energy densities at low temperatures and provides high energy densities and high power densities at moderate temperatures.

  14. An Evolutionary Arms Race for Sulfur

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

    globally distributed sulfur-oxidizing bacteria in the deep sea carry bacterial genes for the oxidation of elemental sulfur. Although such observations are common in...

  15. Design and Synthesis of Novel Diluted Magnetic Semiconductors...

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

    Design and Synthesis of Novel Diluted Magnetic Semiconductors Diluted magnetic semiconductors (DMSs) are semiconductors doped with small amounts of magnetic active transition...

  16. Dilute Clean Diesel Combustion Achieves Low Emissions and High...

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

    Dilute Clean Diesel Combustion Achieves Low Emissions and High Efficiency While Avoiding Control Problems of HCCI Dilute Clean Diesel Combustion Achieves Low Emissions and High ...

  17. Diluted equilibrium sterile neutrino dark matter (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Diluted equilibrium sterile neutrino dark matter Citation Details In-Document Search This content will become publicly available on November 5, 2016 Title: Diluted equilibrium ...

  18. Diluted equilibrium sterile neutrino dark matter (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Diluted equilibrium sterile neutrino dark matter This content will become publicly available on November 5, 2016 Prev Next Title: Diluted equilibrium sterile neutrino dark ...

  19. Recovery of organic acids

    DOE Patents [OSTI]

    Verser, Dan W. (Menlo Park, CA); Eggeman, Timothy J. (Lakewood, CO)

    2011-11-01

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  20. Recovery of organic acids

    DOE Patents [OSTI]

    Verser, Dan W. (Golden, CO); Eggeman, Timothy J. (Lakewood, CO)

    2009-10-13

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  1. Method of preparing graphene-sulfur nanocomposites for rechargeable lithium-sulfur battery electrodes

    SciTech Connect (OSTI)

    Liu, Jun; Lemmon, John P; Yang, Zhenguo; Cao, Yuliang; Li, Xiaolin

    2015-04-07

    A method of preparing a graphene-sulfur nanocomposite for a cathode in a rechargeable lithium-sulfur battery comprising thermally expanding graphite oxide to yield graphene layers, mixing the graphene layers with a first solution comprising sulfur and carbon disulfide, evaporating the carbon disulfide to yield a solid nanocomposite, and grinding the solid nanocomposite to yield the graphene-sulfur nanocomposite. Rechargeable-lithium-sulfur batteries having a cathode that includes a graphene-sulfur nanocomposite can exhibit improved characteristics. The graphene-sulfur nanocomposite can be characterized by graphene sheets with particles of sulfur adsorbed to the graphene sheets. The sulfur particles have an average diameter of less than 50 nm.

  2. Graphene-sulfur nanocomposites for rechargeable lithium-sulfur battery electrodes

    DOE Patents [OSTI]

    Liu, Jun; Lemmon, John P; Yang, Zhenguo; Cao, Yuiliang; Li, Xiaolin

    2014-06-17

    Rechargeable lithium-sulfur batteries having a cathode that includes a graphene-sulfur nanocomposite can exhibit improved characteristics. The graphene-sulfur nanocomposite can be characterized by graphene sheets with particles of sulfur adsorbed to the graphene sheets. The sulfur particles have an average diameter less than 50 nm..

  3. Alkali metal/sulfur battery

    DOE Patents [OSTI]

    Anand, Joginder N.

    1978-01-01

    Alkali metal/sulfur batteries in which the electrolyte-separator is a relatively fragile membrane are improved by providing means for separating the molten sulfur/sulfide catholyte from contact with the membrane prior to cooling the cell to temperatures at which the catholyte will solidify. If the catholyte is permitted to solidify while in contact with the membrane, the latter may be damaged. The improvement permits such batteries to be prefilled with catholyte and shipped, at ordinary temperatures.

  4. HYBRID SULFUR ELECTROLYZER DEVELOPMENT FY09 SECOND QUARTER REPORT

    SciTech Connect (OSTI)

    Herman, D; David Hobbs, D; Hector Colon-Mercado, H; Timothy Steeper, T; John Steimke, J; Mark Elvington, M

    2009-04-15

    The primary objective of the DOE-NE Nuclear Hydrogen Initiative (NHI) is to develop the nuclear hydrogen production technologies necessary to produce hydrogen at a cost competitive with other alternative transportation fuels. The focus of the NHI is on thermochemical cycles and high temperature electrolysis that can be powered by heat from high temperature gas reactors. The Savannah River National Laboratory (SRNL) has been tasked with the primary responsibility to perform research and development in order to characterize, evaluate and develop the Hybrid Sulfur (HyS) thermochemical process. This report documents work during the first quarter of Fiscal Year 2009, for the period between January 1, 2009 and March 31, 2009. The HyS Process is a two-step hybrid thermochemical cycle that is part of the 'Sulfur Family' of cycles. As a sulfur cycle, it uses high temperature thermal decomposition of sulfuric acid to produce oxygen and to regenerate the sulfur dioxide reactant. The second step of the process uses a sulfur dioxide depolarized electrolyzer (SDE) to split water and produce hydrogen by electrochemically reacting sulfur dioxide with H{sub 2}O. The SDE produces sulfuric acid, which is then sent to the acid decomposer to complete the cycle. The DOE NHI program is developing the acid decomposer at Sandia National Laboratory for application to both the HyS Process and the Sulfur Iodine Cycle. The SDE is being developed at SRNL. During FY05 and FY06, SRNL designed and conducted proof-of-concept testing for a SDE using a low temperature, PEM fuel cell-type design concept. The advantages of this design concept include high electrochemical efficiency, small footprint and potential for low capital cost, characteristics that are crucial for successful implementation on a commercial scale. During FY07, SRNL extended the range of testing of the SDE to higher temperature and pressure, conducted a 100-hour longevity test with a 60-cm{sup 2} single cell electrolyzer, and

  5. Redistribution of Lignin Caused by Dilute Acid Pretreatment of Biomass

    SciTech Connect (OSTI)

    Johnson, D. K.; Donohoe, B. S.; Katahira, R.; Tucker, M. P.; Vinzant, T. B.; Himmel, M. E.

    2012-01-01

    Research conducted at NREL has shown that lignin undergoes a phase transition during thermochemical pretreatments conducted above its glass transition temperature. The lignin coalesces within the plant cell wall and appears as microscopic droplets on cell surfaces. It is clear that pretreatment causes significant changes in lignin distribution in pretreatments at all scales from small laboratory reactors to pilot scale reactors. A method for selectively extracting lignin droplets from the surfaces of pretreated cell walls has allowed us to characterize the chemical nature and molecular weight distribution of this fraction. The effect of lignin redistribution on the digestibility of pretreated solids has also been tested. It is clear that removal of the droplets increases the digestibility of pretreated corn stover. The improved digestibility could be due to decreased non-specific binding of enzymes to lignin in the droplets, or because the droplets no longer block access to cellulose.

  6. Diluted magnetic semiconductor nanowires exhibiting magnetoresistance

    DOE Patents [OSTI]

    Yang, Peidong; Choi, Heonjin; Lee, Sangkwon; He, Rongrui; Zhang, Yanfeng; Kuykendal, Tevye; Pauzauskie, Peter

    2011-08-23

    A method for is disclosed for fabricating diluted magnetic semiconductor (DMS) nanowires by providing a catalyst-coated substrate and subjecting at least a portion of the substrate to a semiconductor, and dopant via chloride-based vapor transport to synthesize the nanowires. Using this novel chloride-based chemical vapor transport process, single crystalline diluted magnetic semiconductor nanowires Ga.sub.1-xMn.sub.xN (x=0.07) were synthesized. The nanowires, which have diameters of .about.10 nm to 100 nm and lengths of up to tens of micrometers, show ferromagnetism with Curie temperature above room temperature, and magnetoresistance up to 250 Kelvin.

  7. Investigation of Sulfur Deactivation on Cu/Zeolite SCR Catalysts...

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

    Sulfur Deactivation on CuZeolite SCR Catalysts in Diesel Application Investigation of Sulfur Deactivation on CuZeolite SCR Catalysts in Diesel Application Investigation of Sulfur ...

  8. Identification of Martian Regolith Sulfur Components In Shergottites...

    Office of Scientific and Technical Information (OSTI)

    Sulfur Components In Shergottites Using Sulfur K XANES and FeS Ratios. Citation Details In-Document Search Title: Identification of Martian Regolith Sulfur Components In ...

  9. Simultaneous removal of nitrogen oxides and sulfur oxides from combustion gases

    DOE Patents [OSTI]

    Clay, David T.; Lynn, Scott

    1976-10-19

    A process for the simultaneous removal of sulfur oxides and nitrogen oxides from power plant stack gases comprising contacting the stack gases with a supported iron oxide catalyst/absorbent in the presence of sufficient reducing agent selected from the group consisting of carbon monoxide, hydrogen, and mixtures thereof, to provide a net reducing atmosphere in the SO.sub.x /NO.sub.x removal zone. The sulfur oxides are removed by absorption substantially as iron sulfide, and nitrogen oxides are removed by catalytic reduction to nitrogen and ammonia. The spent iron oxide catalyst/absorbent is regenerated by oxidation and is recycled to the contacting zone. Sulfur dioxide is also produced during regeneration and can be utilized in the production of sulfuric acid and/or sulfur.

  10. FY08 MEMBRANE CHARACTERIZATION REPORT FOR HYBRID SULFUR ELECTROLYZER

    SciTech Connect (OSTI)

    Hobbs, D; Hector Colon-Mercado, H; Mark Elvington, M

    2008-09-01

    This report summarizes results from all of the membrane testing completed to date at the Savannah River National Laboratory (SRNL) for the sulfur dioxide-depolarized electrolyzer (SDE). Several types of commercially-available membranes have been analyzed for ionic resistance and sulfur dioxide transport including perfluorinated sulfonic acid (PFSA), sulfonated polyether-ketone-ketone (SPEKK), and polybenzimidazole membranes (PBI). Of these membrane types, the poly-benzimidazole membrane, Celtec-L, exhibited the best combination of characteristics for use in an SDE. Several experimental membranes have also been analyzed including hydrated sulfonated Diels-Alder polyphenylenes (SDAPP) membranes from Sandia National Laboratory, perfluorosulfonimide (PFSI) and sulfonated perfluorocyclobutyl aromatic ether (S-PFCB) prepared by Clemson University, hydrated platinum-treated PFSA prepared by Giner Electrochemical Systems (GES) and Pt-Nafion{reg_sign} 115 composites prepared at SRNL. The chemical stability, SO{sub 2} transport and ionic conductivity characteristics have been measured for several commercially available and experimental proton-conducting membranes. Commercially available PFSA membranes such as the Nafion{reg_sign} series exhibited excellent chemical stability and ionic conductivity in sulfur dioxide saturated sulfuric acid solutions. Sulfur dioxide transport in the Nafion{reg_sign} membranes varied proportionally with the thickness and equivalent weight of the membrane. Although the SO{sub 2} transport in the Nafion{reg_sign} membranes is higher than desired, the excellent chemical stability and conductivity makes this membrane the best commercially-available membrane at this time. Initial results indicated that a modified Nafion{reg_sign} membrane incorporating Pt nanoparticles exhibited significantly reduced SO{sub 2} transport. Reduced SO{sub 2} transport was also measured with commercially available PBI membrane and several experimental membranes produced

  11. Combining automatic titration of total iron and sulfur in thermal battery materials

    SciTech Connect (OSTI)

    Marley, N.A.

    1986-05-28

    Optimal thermal battery performance requires careful control of the iron disulfide content in the catholyte mixture. Previously, the iron and sulfur content of battery materials was determined separately, each requiring a lengthy sample preparation and clean up procedure. A new method has been developed which allows both determinations to be made on the same sample following a simple dissolution procedure. Sample preparation requires oxidation and dissolution with nitric acid followed by dissolution in hydrochloric acid. Iron and sulfur are then determined on sample aliquots by automatic titration. The implementation of this combined procedure for the determination of iron and sulfur by automatic titration has resulted in a substantial reduction in the analysis time. Since sample aliquots are used for each determination, the need to repeat a sample for analysis is rare, improving both the analytical efficiency and sample throughput. Results obtained for sulfur show an improved precision.

  12. Assessing historical global sulfur emission patterns for the period 1850--1990

    SciTech Connect (OSTI)

    Lefohn, A.S.; Husar, J.D.; Husar, R.B.; Brimblecombe, P.

    1996-07-19

    Anthropogenic sulfur dioxide emissions from energy-producing and metal production activities have become an important factor in better understanding the relationship between humans and the environment. Concerns about (1) acid rain effects on the environment and (2) anthropogenic aerosols affecting possible global change have prompted interest in the transformation and fate of sulfur in the environment. One step in assessing the importance of sulfur emissions is the development of a reliable regional emission inventory of sulfur as a function of time. The objective of this research effort was to create a homogeneous database for historical sulfur emission estimates for the world. The time from 1850--1990 was selected to include the period of industrialization form the time the main production of fuels and minerals began until the most recent year for which complete production data exist. This research effort attempts to correct some of the deficiencies associated with previous global sulfur emission estimates by (1) identifying those production activities that resulted in sulfur emissions by country and (2) calculating historical emission trends by country across years. An important component of this study was the comparison of the sulfur emission results with those of previous studies.

  13. LOW SULFUR HOME HEATING OIL DEMONSTRATION PROJECT SUMMARY REPORT.

    SciTech Connect (OSTI)

    BATEY, J.E.; MCDONALD, R.J.

    2005-06-01

    the potential service costs reduction, it is very significant. It represents an important reduction in air pollutants that contribute directly to acid rain and other adverse impacts in the United States. When all air emissions are included, low sulfur content home heating oil and utility gas are virtually equal in their environmental impacts.

  14. Moment enhancement in dilute magnetic semiconductors: MnxSi1...

    Office of Scientific and Technical Information (OSTI)

    Moment enhancement in dilute magnetic semiconductors: MnxSi1-x with x 0.1% Citation Details In-Document Search Title: Moment enhancement in dilute magnetic semiconductors: ...

  15. Mitigation of Sulfur Poisoning of Ni/Zirconia SOFC Anodes by Antimony and Tin

    SciTech Connect (OSTI)

    Marina, Olga A.; Coyle, Christopher A.; Engelhard, Mark H.; Pederson, Larry R.

    2011-02-28

    Surface Ni/Sb and Ni/Sb alloys were found to efficiently minimize the negative effects of sulfur on the performance of Ni/zirconia anode-supported solid oxide fuel cells (SOFC). Prior to operating on fuel gas containing low concentrations of H2S, the nickel/zirconia anodes were briefly exposed to antimony or tin vapor, which only slightly affected the SOFC performance. During the subsequent exposures to 1 and 5 ppm H2S, increases in anodic polarization losses were minimal compared to those observed for the standard nickel/zirconia anodes. Post-test XPS analyses showed that Sb and Sn tended to segregate to the surface of Ni particles, and further confirmed a significant reduction of adsorbed sulfur on the Ni surface in Ni/Sn and Ni/Sb samples compared to the Ni. The effect may be the result of weaker sulfur adsorption on bimetallic surfaces, adsorption site competition between sulfur and Sb or Sn on Ni, or other factors. The use of dilute binary alloys of Ni-Sb or Ni-Sn in the place of Ni, or brief exposure to Sb or Sn vapor, may be effective means to counteract the effects of sulfur poisoning in SOFC anodes and Ni catalysts. Other advantages, including suppression of coking or tailoring the anode composition for the internal reforming, are also expected.

  16. Seal for sodium sulfur battery

    DOE Patents [OSTI]

    Topouzian, Armenag; Minck, Robert W.; Williams, William J.

    1980-01-01

    This invention is directed to a seal for a sodium sulfur battery in which the sealing is accomplished by a radial compression seal made on a ceramic component of the battery which separates an anode compartment from a cathode compartment of the battery.

  17. Recovery of sulfur from native ores

    SciTech Connect (OSTI)

    Womack, J.T.; Wiewiorowski, T.K.; Astley, V.C.; Perez, J.W.; Headington, T.A.

    1992-03-17

    This patent describes a process for removing elemental sulfur from ores containing elemental sulfur. It comprises crushing a sulfur-containing ore to a coarse particle size wherein ore particles produced during crushing enable substantially all of the sulfur to be liberated during a heating step and to produce an ore gangue that is substantially not susceptible to flotation: forming an aqueous ore slurry containing about 50-80% by weight of solids from the crushed ore and adjusting the pH to at least a pH of about 8.0; heating the aqueous ore slurry formed in step (b) under elevated pressure to a temperature of about 240{degrees} - 315{degrees} F. for sufficient time to melt and liberate elemental sulfur contained in the ore to produce liberated molten sulfur and ore gangue, wherein the slurry is heated while agitating the slurry at sufficient velocity to substantially maintain the ore, ore gangue and liberated molten sulfur in suspension; cooling the heated slurry sufficiently to resolidify the liberated molten sulfur; conditioning the aqueous slurry of step (d) with a flotation aid; separating the condition aqueous slurry of ore gangue and resolidified sulfur in a flotation unit to produce a sulfur-rich flotation concentrate overstream; and recovering the sulfur-rich flotation concentrate and separating the sulfur therefrom.

  18. Two stage sorption of sulfur compounds

    DOE Patents [OSTI]

    Moore, William E.

    1992-01-01

    A two stage method for reducing the sulfur content of exhaust gases is disclosed. Alkali- or alkaline-earth-based sorbent is totally or partially vaporized and introduced into a sulfur-containing gas stream. The activated sorbent can be introduced in the reaction zone or the exhaust gases of a combustor or a gasifier. High efficiencies of sulfur removal can be achieved.

  19. Process for reducing sulfur in coal char

    DOE Patents [OSTI]

    Gasior, Stanley J.; Forney, Albert J.; Haynes, William P.; Kenny, Richard F.

    1976-07-20

    Coal is gasified in the presence of a small but effective amount of alkaline earth oxide, hydroxide or carbonate to yield a char fraction depleted in sulfur. Gases produced during the reaction are enriched in sulfur compounds and the alkaline earth compound remains in the char fraction as an alkaline earth oxide. The char is suitable for fuel use, as in a power plant, and during combustion of the char the alkaline earth oxide reacts with at least a portion of the sulfur oxides produced from the residual sulfur contained in the char to further lower the sulfur content of the combustion gases.

  20. CLOSEOUT REPORT FOR HYBRID SULFUR PRESSURIZED BUTTON CELL TEST FACILITY

    SciTech Connect (OSTI)

    Steeper, T.

    2010-09-15

    This document is the Close-Out Report for design and partial fabrication of the Pressurized Button Cell Test Facility at Savannah River National Laboratory (SRNL). This facility was planned to help develop the sulfur dioxide depolarized electrolyzer (SDE) that is a key component of the Hybrid Sulfur Cycle for generating hydrogen. The purpose of this report is to provide as much information as possible in case the decision is made to resume research. This report satisfies DOE Milestone M3GSR10VH030107.0. The HyS Cycle is a hybrid thermochemical cycle that may be used in conjunction with advanced nuclear reactors or centralized solar receivers to produce hydrogen by watersplitting. The HyS Cycle utilizes the high temperature (>800 C) thermal decomposition of sulfuric acid to produce oxygen and regenerate sulfur dioxide. The unique aspect of HyS is the generation of hydrogen in a water electrolyzer that is operated under conditions where dissolved sulfur dioxide depolarizes the anodic reaction, resulting in substantial voltage reduction. Low cell voltage is essential for both high thermodynamic efficiency and low hydrogen cost. Sulfur dioxide is oxidized at the anode, producing sulfuric acid that is sent to the high temperature acid decomposition portion of the cycle. Sulfur dioxide from the decomposer is cycled back to electrolyzers. The electrolyzer cell uses the membrane electrode assembly (MEA) concept. Anode and cathode are formed by spraying a catalyst, typically platinized carbon, on both sides of a Proton Exchange Membrane (PEM). SRNL has been testing SDEs for several years including an atmospheric pressure Button Cell electrolyzer (2 cm{sup 2} active area) and an elevated temperature/pressure Single Cell electrolyzer (54.8 cm{sup 2} active area). SRNL tested 37 MEAs in the Single Cell electrolyzer facility from June 2005 until June 2009, when funding was discontinued. An important result of the final months of testing was the development of a method that

  1. Motor-mediated microtubule self-organization in dilute and semi-dilute filament solutions.

    SciTech Connect (OSTI)

    Swaminathan, S.; Ziebert, F.; Aranson, I. S.; Karpeev, D.

    2011-01-01

    We study molecular motor-induced microtubule self-organization in dilute and semi-dilute filament solutions. In the dilute case, we use a probabilistic model of microtubule interaction via molecular motors to investigate microtubule bundle dynamics. Microtubules are modeled as polar rods interacting through fully inelastic, binary collisions. Our model indicates that initially disordered systems of interacting rods exhibit an orientational instability resulting in spontaneous ordering. We study the existence and dynamic interaction of microtubule bundles analytically and numerically. Our results reveal a long term attraction and coalescing of bundles indicating a clear coarsening in the system; microtubule bundles concentrate into fewer orientations on a slow logarithmic time scale. In semi-dilute filament solutions, multiple motors can bind a filament to several others and, for a critical motor density, induce a transition to an ordered phase with a nonzero mean orientation. Motors attach to a pair of filaments and walk along the pair bringing them into closer alignment. We develop a spatially homogenous, mean-field theory that explicitly accounts for a force-dependent detachment rate of motors, which in turn affects the mean and the fluctuations of the net force acting on a filament. We show that the transition to the oriented state can be both continuous and discontinuous when the force-dependent detachment of motors is important.

  2. Investigation of the sulfur and lithium to sulfur ratio threshold in stress corrosion cracking of sensitized alloy 600 in borated thiosulfate solution

    SciTech Connect (OSTI)

    Bandy, R.; Kelly, K.

    1984-07-01

    The stress corrosion cracking of sensitized Alloy 600 was investigated in aerated solutions of sodium thiosulfate generally containing 1.3% boric acid. The aim of the investigation, among others, was to determine the existence, if any, of a threshold level of sulfur, and lithium to sulfur ratio governing the SCC. Specimens were first solution annealed at 1135/sup 0/C for 45 minutes, water quenched, and then sensitized at 621/sup 0/C for 18 hours. Reverse U-bends were tested at room temperature, whereas slow strain rate and constant load tests were performed at 80/sup 0/C. All tests were performed in solutions open to the atmosphere. The results indicate that in the borated thiosulfate solution containing 7 ppM sulfur, 5 ppM lithium as lithium hydroxide is sufficient to inhibit SCC in U-bends. The occurrence of inhibition seems to correlate to the rapid increase of pH and conductivity of the solution as a result of the lithium hydroxide addition. In the slow strain rate tests in the borated solution containing 0.7 ppM lithium as lithium hydroxide, significant stress corrosion cracking is observed at a sulfur level of 30 ppb, i.e., a lithium to sulfur ratio of 23. In a parallel test in 30 ppb sulfur level but without any lithium hydroxide, the stress corrosion cracking is more severe than that in the lithiated environment, thus implying that lithium hydroxide plays some role in the stress corrosion cracking inhibition.

  3. Biogenic sulfur emissions in the SURE region

    SciTech Connect (OSTI)

    Adams, D.F.; Farwell, S.O.; Robinson, E.; Pack, M.R.

    1980-09-01

    The objective of this study was to estimate the magnitude of biogenic sulfur emissions from the northeastern United States - defined as the EPRI Sulfate Regional Experiment (SURE) study area. Initial laboratory efforts developed and validated a portable sulfur sampling system and a sensitive, gas chromatographic analytical detection system. Twenty-one separate sites were visited in 1977 to obtain a representative sulfur emission sampling of soil orders, suborders, and wetlands. The procedure determined the quantity of sulfur added to sulfur-free sweep air by the soil flux as the clean air was blown through the dynamic enclosure set over the selected sampling area. This study represents the first systematic sampling for biogenic sulfur over such a wide range of soils and such a large land area. The major impacts upon the measured sulfur flux were found to include soil orders, temperature, sunlight intensity, tidal effects along coastal areas. A mathematical model was developed for biogenic sulfur emissions which related these field variables to the mean seasonal and annual ambient temperatures regimes for each SURE grid and the percentage of each soil order within each grid. This model showed that at least 53,500 metric tons (MT) of biogenic sulfur are emitted from the SURE land surfaces and approximately 10,000 MT are emitted from the oceanic fraction of the SURE grids. This equates to a land sulfur flux of nearly 0.02 gram of sulfur per square meter per yr, or about 0.6% of the reported anthropogenic emissions withn the SURE study area. Based upon these data and the summertime Bermuda high clockwise circulation of maritime air across Florida and the Gulf Coast states northward through the SURE area, the total land biogenic sulfur emission contribution to the SURE area atmospheric sulfur burden might approach 1 to 2.5% of the anthropogenic.

  4. Reduction mechanism of sulfur in lithium-sulfur battery: From elemental sulfur to polysulfide

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zheng, Dong; Yang, Xuran; Zhang, Xiaoqing; Wang, Jiankun; Qu, Deyu; Qu, Deyang

    2015-10-30

    In this study, the polysulfide ions formed during the first reduction wave of sulfur in Li–S battery were determined through both in-situ and ex-situ derivatization of polysulfides. By comparing the cyclic voltammetric results with and without the derivatization reagent (methyl triflate) as well as the in-situ and ex-situ derivatization results under potentiostatic condition, in-situ derivatization was found to be more appropriate than its ex-situ counterpart, since subsequent fast chemical reactions between the polysulfides and sulfur may occur during the timeframe of ex-situ procedures. It was found that the major polysulfide ions formed at the first reduction wave of elemental sulfurmore » were the S42– and S52– species, while the widely accepted reduction products of S82– and S62– for the first reduction wave were in low abundance.« less

  5. Characterization of the Dilute Ising Antiferromagnet

    SciTech Connect (OSTI)

    Wiener, T.

    2000-09-12

    A spin glass is a magnetic ground state in which ferromagnetic and antiferromagnetic exchange interactions compete, thereby creating frustration and a multidegenerate state with no long range order. An Ising system is a system where the spins are constrained to lie parallel or antiparallel to a primary axis. There has been much theoretical interest in the past ten years in the effects of applying a magnetic field transverse to the primary axis in an Ising spin glass at low temperatures and thus study phase transitions at the T=0 limit. The focus of this study is to search for and characterize a new Ising spin glass system. This is accomplished by site diluting yttrium for terbium in the crystalline material TbNi{sub 2}Ge{sub 2}. The first part of this work gives a brief overview of the physics of rare earth magnetism and an overview of experimental characteristics of spin glasses. This is followed by the methodology used to manufacture the large single crystals used in this study, as well as the measurement techniques used. Next, a summary of the results of magnetic measurements on across the dilution series from pure terbium to pure yttrium is presented. This is followed by detailed measurements on particular dilutions which demonstrate spin glass behavior. Pure TbNi{sub 2}Ge{sub 2} is an Ising antiferromagnet with a several distinct metamagnetic states below 17 K. As the terbium is alloyed with yttrium, these magnetic states are weakened in a consistent manner, as is seen in measurements of the transition temperatures and analysis of Curie-Weiss behavior at high temperature. At low concentrations of terbium, below 35%, long range order is no longer present and a spin-glass-like state emerges. This state is studied through various measurements, dc and ac susceptibility, resistivity, and specific heat. This magnetic behavior was then compared to that of other well characterized spin glasses. It is concluded that there is a region of concentration s for which a spin

  6. Reduction mechanism of sulfur in lithium-sulfur battery: From elemental sulfur to polysulfide

    SciTech Connect (OSTI)

    Zheng, Dong; Yang, Xuran; Zhang, Xiaoqing; Wang, Jiankun; Qu, Deyu; Qu, Deyang

    2015-10-30

    In this study, the polysulfide ions formed during the first reduction wave of sulfur in Li–S battery were determined through both in-situ and ex-situ derivatization of polysulfides. By comparing the cyclic voltammetric results with and without the derivatization reagent (methyl triflate) as well as the in-situ and ex-situ derivatization results under potentiostatic condition, in-situ derivatization was found to be more appropriate than its ex-situ counterpart, since subsequent fast chemical reactions between the polysulfides and sulfur may occur during the timeframe of ex-situ procedures. It was found that the major polysulfide ions formed at the first reduction wave of elemental sulfur were the S42– and S52– species, while the widely accepted reduction products of S82– and S62– for the first reduction wave were in low abundance.

  7. Dilute Oxygen Combustion - Phase 3 Report

    SciTech Connect (OSTI)

    Riley, Michael F.

    2000-05-31

    Dilute Oxygen Combustion (DOC) burners have been successfully installed and operated in the reheat furnace at Auburn Steel Co., Inc., Auburn, NY, under Phase 3 of the Dilute Oxygen Combustion project. Two new preheat zones were created employing a total of eight 6.5 MMBtu/hr capacity burners. The preheat zones provide a 30 percent increase in maximum furnace production rate, from 75 tph to 100 tph. The fuel rate is essentially unchanged, with the fuel savings expected from oxy-fuel combustion being offset by higher flue gas temperatures. When allowance is made for the high nitrogen level and high gas phase temperature in the furnace, measured NOx emissions are in line with laboratory data on DOC burners developed in Phase 1 of the project. Burner performance has been good, and there have been no operating or maintenance problems. The DOC system continues to be used as part of Auburn Steel's standard reheat furnace practice. High gas phase temperature is a result of the high firing density needed to achieve high production rates, and little opportunity exists for improvement in that area. However, fuel and NOx performance can be improved by further conversion on furnace zones to DOC burners, which will lower furnace nitrogen levels. Major obstacles are cost and concern about increased formation of oxide scale on the steel. Oxide scale formation may be enhanced by exposure of the steel to higher concentrations of oxidizing gas components (primarily products of combustion) in the higher temperature zones of the furnace. Phase 4 of the DOC project will examine the rate of oxide scale formation in these higher temperature zones and develop countermeasures that will allow DOC burners to be used successfully in these furnace zones.

  8. Dilute Oxygen Combustion Phase 3 Final Report

    SciTech Connect (OSTI)

    Riley, M.F.; Ryan, H.M.

    2000-05-31

    Dilute Oxygen Combustion (DOC) burners have been successfully installed and operated in the reheat furnace at Auburn Steel Co., Inc., Auburn, NY, under Phase 3 of the Dilute Oxygen Combustion project. Two new preheat zones were created employing a total of eight 6.5 MMBtu/hr capacity burners. The preheat zones provide a 30 percent increase in maximum furnace production rate, from 75 tph to 100 tph. The fuel rate is essentially unchanged, with the fuel savings expected from oxy-fuel combustion being offset by higher flue gas temperatures. When allowance is made for the high nitrogen level and high gas phase temperature in the furnace, measured NOx emissions are in line with laboratory data on DOC burners developed in Phase 1 of the project. Burner performance has been good and there have been no operating or maintenance problems. The DOC system continues to be used as part of Auburn Steel?s standard reheat furnace practice. High gas phase temperature is a result of the high firing density needed to achieve high production rates, and little opportunity exists for improvement in that area. However, fuel and NOx performance can be improved by further conversion of furnace zones to DOC burners, which will lower furnace nitrogen levels. Major obstacles are cost and concern about increased formation of oxide scale on the steel. Oxide scale formation may be enhanced by exposure of the steel to higher concentrations of oxidizing gas components (primarily products of combustion) in the higher temperature zones of the furnace. Phase 4 of the DOC project will examine the rate of oxide scale formation in these higher temperature zones and develop countermeasures that will allow DOC burners to be used successfully in these furnace zones.

  9. HYDROCARBON AND SULFUR SENSORS FOR SOFC SYSTEMS

    SciTech Connect (OSTI)

    A.M. Azad; Chris Holt; Todd Lesousky; Scott Swartz

    2003-11-01

    The following report summarizes work conducted during the Phase I program Hydrocarbon and Sulfur Sensors for SOFC Systems under contract No. DE-FC26-02NT41576. For the SOFC application, sensors are required to monitor hydrocarbons and sulfur in order to increase the operation life of SOFC components. This report discusses the development of two such sensors, one based on thick film approach for sulfur monitoring and the second galvanic based for hydrocarbon monitoring.

  10. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print Wednesday, 29 November 2006 00:00 The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted

  11. Investigation of CTBT OSI Radionuclide Techniques at the DILUTED...

    Office of Scientific and Technical Information (OSTI)

    WATERS Nuclear Test Site Citation Details In-Document Search Title: Investigation of CTBT OSI Radionuclide Techniques at the DILUTED WATERS Nuclear Test Site Under the ...

  12. Dilute Surfactant Methods for Carbonate Formations

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2006-02-01

    There are many fractured carbonate reservoirs in US (and the world) with light oil. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). The process of using dilute anionic surfactants in alkaline solutions has been investigated in this work for oil recovery from fractured oil-wet carbonate reservoirs both experimentally and numerically. This process is a surfactant-aided gravity drainage where surfactant diffuses into the matrix, lowers IFT and contact angle, which decrease capillary pressure and increase oil relative permeability enabling gravity to drain the oil up. Anionic surfactants have been identified which at dilute concentration of 0.05 wt% and optimal salinity can lower the interfacial tension and change the wettability of the calcite surface to intermediate/water-wet condition as well or better than the cationic surfactant DTAB with a West Texas crude oil. The force of adhesion in AFM of oil-wet regions changes after anionic surfactant treatment to values similar to those of water-wet regions. The AFM topography images showed that the oil-wetting material was removed from the surface by the anionic surfactant treatment. Adsorption studies indicate that the extent of adsorption for anionic surfactants on calcite minerals decreases with increase in pH and with decrease in salinity. Surfactant adsorption can be minimized in the presence of Na{sub 2}CO{sub 3}. Laboratory-scale surfactant brine imbibition experiments give high oil recovery (20-42% OOIP in 50 days; up to 60% in 200 days) for initially oil-wet cores through wettability alteration and IFT reduction. Small (<10%) initial gas saturation does not affect significantly the rate of oil recovery in the imbibition process, but larger gas saturation decreases the oil recovery rate. As the core permeability decreases, the rate of oil recovery reduces

  13. Method of removing oxides of sulfur and oxides of nitrogen from exhaust gases

    DOE Patents [OSTI]

    Walker, Richard J.

    1986-01-01

    A continuous method is presented for removing both oxides of sulfur and oxides of nitrogen from combustion or exhaust gases with the regeneration of the absorbent. Exhaust gas is cleaned of particulates and HCl by a water scrub prior to contact with a liquid absorbent that includes an aqueous solution of bisulfite and sulfite ions along with a metal chelate, such as, an iron or zinc aminopolycarboxylic acid. Following contact with the combustion gases the spent absorbent is subjected to electrodialysis to transfer bisulfite ions into a sulfuric acid solution while splitting water with hydroxide and hydrogen ion migration to equalize electrical charge. The electrodialysis stack includes alternate layers of anion selective and bipolar membranes. Oxides of nitrogen are removed from the liquid absorbent by air stripping at an elevated temperature and the regenerated liquid absorbent is returned to contact with exhaust gases for removal of sulfur oxides and nitrogen oxides.

  14. Chitosan sorbents for platinum sorption from dilute solutions

    SciTech Connect (OSTI)

    Guibal, E.; Larkin, A.; Vincent, T.; Tobin, J.M.

    1999-10-01

    Chitosan has proved efficient at removing platinum in dilute effluents. The maximum uptake capacity reaches 300 mg/g (almost 1.5 mmol/g). The optimum pH for sorption is pH 2. A glutaraldehyde cross-linking pretreatment is necessary to stabilize the biopolymer in acidic solutions. Sorption isotherms have been studied as a function of pH, sorbent particle size, and the cross-linking ratio. Surprisingly, the extent of the cross-linking (determined by the concentration of the cross-linking agent in the treatment bath) has no significant influence on uptake capacity. Competitor anions such as chloride or nitrate induce a large decrease in the sorption efficiency. Sorption kinetics show also that uptake rate is not significantly changed by increasing either the cross-linking ratio or the particle size of the sorbent. Mass transfer rates are significantly affected by the initial platinum concentration and by the conditioning of the biopolymer. Gel-bead conditioning appears to reduce the sorption rate. While for molybdate and vanadate ions, mass transfer was governed by intraparticle mass transfer, for platinum, both external and intraparticle diffusion control the uptake rate. In contrast with the former ions, platinum does not form polynuclear hydrolyzed species, which are responsible for steric hindrance of diffusion into the polymer network.

  15. Sulfur-carbon nanocomposites and their application as cathode materials in lithium-sulfur batteries

    SciTech Connect (OSTI)

    Liang, Chengdu; Dudney, Nancy J; Howe, Jane Y

    2015-05-05

    The invention is directed in a first aspect to a sulfur-carbon composite material comprising: (i) a bimodal porous carbon component containing therein a first mode of pores which are mesopores, and a second mode of pores which are micropores; and (ii) elemental sulfur contained in at least a portion of said micropores. The invention is also directed to the aforesaid sulfur-carbon composite as a layer on a current collector material; a lithium ion battery containing the sulfur-carbon composite in a cathode therein; as well as a method for preparing the sulfur-composite material.

  16. Stabilized sulfur binding using activated fillers

    DOE Patents [OSTI]

    Kalb, Paul D.; Vagin, Vyacheslav P.; Vagin, Sergey P.

    2015-07-21

    A method of making a stable, sulfur binding composite comprising impregnating a solid aggregate with an organic modifier comprising unsaturated hydrocarbons with at least one double or triple covalent bond between adjacent carbon atoms to create a modifier-impregnated aggregate; heating and drying the modifier-impregnated aggregate to activate the surface of the modifier-impregnated aggregate for reaction with sulfur.

  17. Sulfur oxide adsorbents and emissions control

    DOE Patents [OSTI]

    Li, Liyu; King, David L.

    2006-12-26

    High capacity sulfur oxide absorbents utilizing manganese-based octahedral molecular sieve (Mn--OMS) materials are disclosed. An emissions reduction system for a combustion exhaust includes a scrubber 24 containing these high capacity sulfur oxide absorbents located upstream from a NOX filter 26 or particulate trap.

  18. Dilute Surfactant Methods for Carbonate Formations

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2004-03-31

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. Anionic surfactants (Alfoterra 35, 38) recover more than 40% of the oil in about 50 days by imbibition driven by wettability alteration in the core-scale. Anionic surfactant, Alfoterra-68, recovers about 28% of the oil by lower tension aided gravity-driven imbibition in the core-scale. Residual oil saturation showed little capillary number dependence between 10{sup -5} and 10{sup -2}. Wettability alteration increases as the number of ethoxy groups increases in ethoxy sulfate surfactants. Plans for the next quarter include conducting mobilization, and imbibition studies.

  19. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2005-07-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. Laboratory imbibition tests show that imbibition rate is not very sensitive to the surfactant concentration (in the range of 0.05-0.2 wt%) and small amounts of trapped gas saturation. It is however very sensitive to oil permeability and water-oil-ratio. Less than 0.5 M Na2CO3 is needed for in situ soap generation and low adsorption; NaCl can be added to reach the necessary total salinity. The simulation result matches the laboratory imbibition experimental data. Small fracture spacing and high permeability would be needed for high rate of recovery.

  20. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2004-01-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. Anionic surfactants (SS-6656, Alfoterra 35, 38, 63,65,68) have been identified which can change the wettability of the calcite surface to intermediate/water-wet condition as well or better than the cationic surfactant DTAB with a West Texas crude oil in the presence of Na{sub 2}CO{sub 3}. All the carbonate surfaces (Lithographic Limestone, Marble, Dolomite and Calcite) show similar behavior with respect to wettability alteration with surfactant 4-22. Anionic surfactants (5-166, Alfoterra-33 and Alfoterra-38 and Alfoterra-68), which lower the interfacial tension with a West Texas crude oil to very low values (<10{sup -2} nM/m), have also been identified. Plans for the next quarter include conducting wettability, mobilization, and imbibition studies.

  1. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2003-01-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. We have acquired field oil and core samples and field brine compositions from Marathon. We have conducted preliminary adsorption and wettability studies. Addition of Na{sub 2}CO{sub 3} decreases anionic surfactant adsorption on calcite surface. Receding contact angles increase with surfactant adsorption. Plans for the next quarter include conducting adsorption, phase behavior and wettability studies.

  2. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2003-10-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. We have conducted adsorption, phase behavior, interfacial tension (IFT) and wettability studies. Alfoterra-38 (0.05 wt%), Alfoterra-35 (0.05 wt%), SS-6656 (0.05 wt%), and DTAB (1 wt%) altered the wettability of the initially oil-wet calcite plate to an intermediate/water-wet state. Low IFT ({approx}10{sup -3} dynes/cm) is obtained with surfactants 5-166, Alfoterra-33 and Alfoterra-38. Plans for the next quarter include conducting wettability and mobilization studies.

  3. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2003-07-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. We have conducted adsorption, phase behavior, interfacial tension (IFT) and wettability studies. Addition of Na{sub 2}CO{sub 3} decreases IFT with a minimum at about 0.2 M. Addition of surfactant decreases IFT further. In the absence of surfactant the minerals are oil-wet after aging with crude oil. Addition of surfactant solution decreases the contact angle to intermediate-wet for many surfactants and water-wet for one surfactant. Addition of Na{sub 2}CO{sub 3} decreases anionic surfactant adsorption on calcite surface. Plans for the next quarter include conducting core adsorption, phase behavior, wettability and mobilization studies.

  4. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2003-07-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. We have conducted adsorption, phase behavior and wettability studies. Addition of Na{sub 2}CO{sub 3} decreases IFT with a minimum at about 0.2 M. Addition of surfactant decreases IFT further. In the absence of surfactant the minerals are oil wet after aging with crude oil. Addition of surfactant solution decreases the contact angle to intermediate wettability. Addition of Na{sub 2}CO{sub 3} decreases anionic surfactant adsorption on calcite surface. Plans for the next quarter include conducting adsorption, phase behavior and wettability studies.

  5. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2005-01-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. Imbibition in an originally oil-wet 2D capillary is the fastest in the case of Alf-38 and slowest in the case of DTAB (among the surfactants studied). Force of adhesion studies and contact angle measurements show that greater wettability alteration is possible with these anionic surfactants than the cationic surfactant studied. The water imbibition rate does not increase monotonically with an increase in the surfactant concentration. A numerical model has been developed that fits the rate of imbibition. Plans for the next quarter include conducting simulation and imbibition studies.

  6. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2004-10-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. Simulation studies indicate that both wettability alteration and gravity-driven flow play significant role in oil recovery from fractured carbonates. Anionic surfactants (Alfoterra 35, 38) recover about 55% of the oil in about 150 days by imbibition driven by wettability alteration and low tension in the core-scale. Anionic surfactant, Alfoterra-68, recovers about 40% of the oil by lower tension aided gravity-driven imbibition in the core-scale. Cationic surfactant, DTAB recovers about 35% of the oil. Plans for the next quarter include conducting simulation and imbibition studies.

  7. Dilute Surfactant Methods for Carbonate Formations

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2005-10-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the best hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. Laboratory-scale surfactant brine imbibition experiments give high oil recovery (35-62% OOIP) for initially oil-wet cores through wettability alteration and IFT reduction. Core-scale simulation results match those of the experiments. Initial capillarity-driven imbibition gives way to a final gravity-driven process. As the matrix block height increases, surfactant alters wettability to a lesser degree, or permeability decreases, oil production rate decreases. The scale-up to field scale will be further studied in the next quarter.

  8. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    SciTech Connect (OSTI)

    Kishore K. Mohanty

    2005-04-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. Laboratory imbibition tests show about 61% oil recovery in the case of Alf-38 and 37% in the case of DTAB. A numerical model has been developed that fits the rate of imbibition of the laboratory experiment. Field-scale fracture block simulation shows that as the fracture spacing increases, so does the time of recovery. Plans for the next quarter include simulation studies.

  9. Method of removal of sulfur from coal and petroleum products

    DOE Patents [OSTI]

    Verkade, John G.; Mohan, Thyagarajan; Angelici, Robert J.

    1995-01-01

    A method for the removal of sulfur from sulfur-bearing materials such as coal and petroleum products using organophosphine and organophosphite compounds is provided.

  10. Baseload CSP Generation Integrated with Sulfur-Based Thermochemical...

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

    Baseload CSP Generation Integrated with Sulfur-Based Thermochemical Heat Storage - FY13 Q1 Baseload CSP Generation Integrated with Sulfur-Based Thermochemical Heat Storage - FY13 ...

  11. Additives and Cathode Materials for High-Energy Lithium Sulfur...

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

    Additives and Cathode Materials for High-Energy Lithium Sulfur Batteries Additives and Cathode Materials for High-Energy Lithium Sulfur Batteries 2013 DOE Hydrogen and Fuel Cells...

  12. Scientists Probe Lithium-Sulfur Batteries in Real Time - Joint...

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

    7, 2012, Videos Scientists Probe Lithium-Sulfur Batteries in Real Time Lithium-sulfur batteries are a promising technology that could some day power electric vehicles. Scientists ...

  13. Understanding Lithium-Sulfur Batteries at the Molecular Level...

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

    June 17, 2015, Accomplishments Understanding Lithium-Sulfur Batteries at the Molecular Level Conceived some 40 years ago, the lithium-sulfur battery can store, in theory, ...

  14. Sulfur Poisoning of Metal Membranes for Hydrogen Separation ...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Sulfur Poisoning of Metal Membranes for Hydrogen Separation Citation Details In-Document Search Title: Sulfur Poisoning of Metal Membranes for Hydrogen Separation ...

  15. The determination of sulfur and chlorine in used oil by X-ray fluorescence, ICP and ion chromatography

    SciTech Connect (OSTI)

    Kendall, D.S.; Siao, M.; Hendricks, S.; Schoenwald, S.D.

    1995-12-31

    Methods for the determination of total sulfur and chlorine in used oil were evaluated and compared using actual waste oil samples. Oxygen bomb combustion was followed by either ion chromatographic determination of sulfate and chloride or determination of sulfur by inductively coupled plasma (ICP) optical emission spectroscopy. Total sulfur and chlorine were determined by X-ray fluorescence (XRF) spectroscopy in samples prepared by fivefold dilution in mineral spirits. Oxygen bomb combustion and XRF gave results with good precision, and, by comparison with each other, very little bias. Problems with the settling of particulates in the XRF analyses were largely overcome by using a thin layer method for sample presentation to the spectrometer. Due to the presence of particulates and emulsified water, the determination of sulfur and chlorine in used oil is more difficult than in pristine oil. Bomb combustion, when followed by IC or ICP, and XRF have been shown to be satisfactory analytical methods for determining total sulfur and chlorine in used or waste oil. 12 refs., 1 fig., 3 tabs.

  16. Dilute Oxygen Combustion Phase I Final Report

    SciTech Connect (OSTI)

    Ryan, H.M.; Riley, M.F.; Kobayashi, H.

    1997-10-31

    A novel burner, in which fuel (natural gas) and oxidant (oxygen or air) are separately injected into a furnace, shows promise for achieving very low nitrogen oxide(s) (NOx) emissions for commercial furnace applications. The dilute oxygen combustion (DOC) burner achieves very low NOx through in-furnace dilution of the oxidant stream prior to combustion, resulting in low flame temperatures, thus inhibiting thermal NOx production. The results of a fundamental and applied research effort on the development of the DOC burner are presented. In addition, the results of a market survey detailing the potential commercial impact of the DOC system are disclosed. The fundamental aspects of the burner development project involved examining the flame characteristics of a natural gas turbulent jet in a high-temperature (~1366 K) oxidant (7-27% O2 vol. wet). Specifically, the mass entrainment rate, the flame lift-off height, the velocity field and major species field of the jet were evaluated as a function of surrounding-gas temperature and composition. The measured entrainment rate of the fuel jet decreased with increasing oxygen content in the surrounding high-temperature oxidant, and was well represented by the d+ scaling correlation found in the literature. The measured flame lift-off height decreased with increasing oxygen content and increasing temperature of the surrounding gas. An increase in surrounding-gas oxygen content and/or temperature inhibited the velocity decay within the jet periphery as a function of axial distance as compared to isothermal turbulent jets. However, the velocity measurements were only broadly represented by the d+ scaling correlation. Several DOC burner configurations were tested in a laboratory-scale furnace at a nominal firing rate of 185 kW (~0.63 MMBtu/h). The flue gas composition was recorded as a function of furnace nitrogen content, furnace temperature, burner geometric arrangement, firing rate, and fuel injection velocity. NOx emissions

  17. Dilute Oxygen Combustion Phase 2 Final Report

    SciTech Connect (OSTI)

    Ryan, H.M.; Riley, M.F.; Kobayashi, H.

    2005-09-30

    A novel burner, in which fuel (natural gas) and oxidant (oxygen or air) are separately injected into a furnace, shows promise for achieving very low nitrogen oxide(s) (NOx) emissions for commercial furnace applications. The dilute oxygen combustion (DOC) burner achieves very low NOx through in-furnace dilution of the oxidant stream prior to combustion, resulting in low flame temperatures, thus inhibiting thermal NOx production. The results of a fundamental and applied research effort on the development of the DOC burner are presented. In addition, the results of a market survey detailing the potential commercial impact of the DOC system are disclosed. The fundamental aspects of the burner development project involved examining the flame characteristics of a natural gas turbulent jet in a high-temperature (~1366 K) oxidant (7-27% O2 vol. wet). Specifically, the mass entrainment rate, the flame lift-off height, the velocity field and major species field of the jet were evaluated as a function of surrounding-gas temperature and composition. The measured entrainment rate of the fuel jet decreased with increasing oxygen content in the surrounding high-temperature oxidant, and was well represented by the d+ scaling correlation found in the literature. The measured flame lift-off height decreased with increasing oxygen content and increasing temperature of the surrounding gas. An increase in surrounding-gas oxygen content and/or temperature inhibited the velocity decay within the jet periphery as a function of axial distance as compared to isothermal turbulent jets. However, the velocity measurements were only broadly represented by the d+ scaling correlation. Several DOC burner configurations were tested in a laboratory-scale furnace at a nominal firing rate of 185 kW (~0.63 MMBtu/h). The flue gas composition was recorded as a function of furnace nitrogen content, furnace temperature, burner geometric arrangement, firing rate, and fuel injection velocity. NOx emissions

  18. Catalyst for elemental sulfur recovery process

    DOE Patents [OSTI]

    Flytzani-Stephanopoulos, M.; Liu, W.

    1995-01-24

    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

  19. Evaluation of a dilute chemical decontaminant for pressurized heavy water reactors

    SciTech Connect (OSTI)

    Velmurugan, S.; Narasimhan, S.V.; Mathur, P.K.; Venkateswarlu, K.S. )

    1991-12-01

    In this paper a dilute chemical decontamination formulation based on ethylene diamine tetraacetic acid, oxalic acid, and citric acid is evaluated for its efficacy in removing oxide layers in a pressurized heavy water reactor (PHWR). An ion exchange system that is specifically suited for fission product-dominated contamination in a PHWR is suggested for the reagent regeneration stage of the decontamination process. An attempt has been made to understand the redeposition behavior of various isotopes during the decontamination process. The polarographic method of identifying the species formed in the dissolution process is explained. Electrochemical measurements are employed to follow the course of oxide removal during the dissolution process. Scanning electron micrographs of metal coupons before and after the dissolution process exemplify the involvement of base metal in the formation of a ferrous oxalate layer. Material compatibility tests between the decontaminant and carbon steel, Monel-400, and Zircaloy-2 are reported.

  20. Dilute Oxygen Combustion Phase IV Final Report

    SciTech Connect (OSTI)

    Riley, M.F.

    2003-04-30

    Novel furnace designs based on Dilute Oxygen Combustion (DOC) technology were developed under subcontract by Techint Technologies, Coraopolis, PA, to fully exploit the energy and environmental capabilities of DOC technology and to provide a competitive offering for new furnace construction opportunities. Capital cost, fuel, oxygen and utility costs, NOx emissions, oxide scaling performance, and maintenance requirements were compared for five DOC-based designs and three conventional air5-fired designs using a 10-year net present value calculation. A furnace direct completely with DOC burners offers low capital cost, low fuel rate, and minimal NOx emissions. However, these benefits do not offset the cost of oxygen and a full DOC-fired furnace is projected to cost $1.30 per ton more to operate than a conventional air-fired furnace. The incremental cost of the improved NOx performance is roughly $6/lb NOx, compared with an estimated $3/lb. NOx for equ8pping a conventional furnace with selective catalytic reduction (SCCR) technology. A furnace fired with DOC burners in the heating zone and ambient temperature (cold) air-fired burners in the soak zone offers low capital cost with less oxygen consumption. However, the improvement in fuel rate is not as great as the full DOC-fired design, and the DOC-cold soak design is also projected to cost $1.30 per ton more to operate than a conventional air-fired furnace. The NOx improvement with the DOC-cold soak design is also not as great as the full DOC fired design, and the incremental cost of the improved NOx performance is nearly $9/lb NOx. These results indicate that a DOC-based furnace design will not be generally competitive with conventional technology for new furnace construction under current market conditions. Fuel prices of $7/MMBtu or oxygen prices of $23/ton are needed to make the DOC furnace economics favorable. Niche applications may exist, particularly where access to capital is limited or floor space limitations

  1. Separation processes using expulsion from dilute supercritical solutions

    DOE Patents [OSTI]

    Cochran, H.D. Jr.

    1993-04-20

    A process is described for separating isotopes as well as other mixtures by utilizing the behavior of dilute repulsive or weakly attractive elements of the mixtures as the critical point of the solvent is approached.

  2. Separation processes using expulsion from dilute supercritical solutions

    DOE Patents [OSTI]

    Cochran, Jr., Henry D.

    1993-01-01

    A process for separating isotopes as well as other mixtures by utilizing the behavior of dilute repulsive or weakly attractive elements of the mixtures as the critical point of the solvent is approached.

  3. A new, safer method of sulfur degassing

    SciTech Connect (OSTI)

    Schico, C.M.; Clem, K.R.; Hartley, D.; Watson, E.A.

    1985-10-01

    The Exxon system for degassing liquid sulfur is presented, and it can reduce total H2S in liquid sulfur to levels as low as 10-15 wppm under the commercial conditions tested. Because Exxon found commercially available mechanical degassing systems to be inadequate, the Claus plant initiated an RandD program to develop the new degassing process. Hydrogen sulfide and hydrogen polysulfide are inherent to the Claus process. The major concerns associated with this H2S in the Claus liquid sulfur include: toxic levels of H2S are possible while loading/unloading liquid sulfur; the H2S lower explosive limit in air can be exceeded in unvented pit/tank vapor space; nuisance odors/environmental concerns; and potential government regulations/ customer restrictions. Results are presented in this article of successful commercial tests using the process at five sites.

  4. Definition of Non-Conventional Sulfur Utilization in Western Kazakhstan for Sulfur Concrete (Phase 1)

    SciTech Connect (OSTI)

    Kalb, Paul

    2007-05-31

    Battelle received a contract from Agip-KCO, on behalf a consortium of international oil and gas companies with exploration rights in the North Caspian Sea, Kazakhstan. The objective of the work was to identify and help develop new techniques for sulfur concrete products from waste, by-product sulfur that will be generated in large quantitites as drilling operations begin in the near future. BNL has significant expertise in the development and use of sulfur concrete products and has direct experience collaborating with the Russian and Kazakh partners that participated. Feasibility testing was successfully conducted for a new process to produce cost-effective sulfur polymer cement that has broad commerical applications.

  5. Method for reducing the sulfur content of a sulfur-containing hydrocarbon stream

    DOE Patents [OSTI]

    Mahajan, Devinder

    2004-12-28

    The sulfur content of a liquid hydrocarbon stream is reduced under mild conditions by contracting a sulfur-containing liquid hydrocarbon stream with transition metal particles containing the transition metal in a zero oxidation state under conditions sufficient to provide a hydrocarbon product having a reduced sulfur content and metal sulfide particles. The transition metal particles can be produced in situ by adding a transition metal precursor, e.g., a transition metal carbonyl compound, to the sulfur-containing liquid feed stream and sonicating the feed steam/transition metal precursor combination under conditions sufficient to produce the transition metal particles.

  6. Dilute Clean Diesel Combustion Achieves Low Emissions and High Efficiency

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

    While Avoiding Control Problems of HCCI | Department of Energy Dilute Clean Diesel Combustion Achieves Low Emissions and High Efficiency While Avoiding Control Problems of HCCI Dilute Clean Diesel Combustion Achieves Low Emissions and High Efficiency While Avoiding Control Problems of HCCI 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters 2005_deer_mueller.pdf (572.11 KB) More Documents & Publications Multicylinder Diesel Engine Design for HCCI Operation

  7. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host

  8. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host

  9. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host

  10. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host

  11. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host

  12. Particulate Matter Characteristics for Highly Dilute Stoichiometric GDI

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

    Engine Operations | Department of Energy Matter Characteristics for Highly Dilute Stoichiometric GDI Engine Operations Particulate Matter Characteristics for Highly Dilute Stoichiometric GDI Engine Operations The overall goal of this study is to help identify which conditions and potential mechanisms impede soot formation in GDI operations. p-24_storey.pdf (602.58 KB) More Documents & Publications Ethanol Effects on Lean-Burn and Stoichiometric GDI Emissions Effects of Advanced

  13. Copper mercaptides as sulfur dioxide indicators

    DOE Patents [OSTI]

    Eller, Phillip G.; Kubas, Gregory J.

    1979-01-01

    Organophosphine copper(I) mercaptide complexes are useful as convenient and semiquantitative visual sulfur dioxide gas indicators. The air-stable complexes form 1:1 adducts in the presence of low concentrations of sulfur dioxide gas, with an associated color change from nearly colorless to yellow-orange. The mercaptides are made by mixing stoichiometric amounts of the appropriate copper(I) mercaptide and phosphine in an inert organic solvent.

  14. Process for removing sulfur from coal

    DOE Patents [OSTI]

    Aida, T.; Squires, T.G.; Venier, C.G.

    1983-08-11

    A process is disclosed for the removal of divalent organic and inorganic sulfur compounds from coal and other carbonaceous material. A slurry of pulverized carbonaceous material is contacted with an electrophilic oxidant which selectively oxidizes the divalent organic and inorganic compounds to trivalent and tetravalent compounds. The carbonaceous material is then contacted with a molten caustic which dissolves the oxidized sulfur compounds away from the hydrocarbon matrix.

  15. Process for removing sulfur from coal

    DOE Patents [OSTI]

    Aida, Tetsuo; Squires, Thomas G.; Venier, Clifford G.

    1985-02-05

    A process for the removal of divalent organic and inorganic sulfur compounds from coal and other carbonaceous material. A slurry of pulverized carbonaceous material is contacted with an electrophilic oxidant which selectively oxidizes the divalent organic and inorganic compounds to trivalent and tetravalent compounds. The carbonaceous material is then contacted with a molten caustic which dissolves the oxidized sulfur compounds away from the hydrocarbon matrix.

  16. Spray drying for high-sulfur coal

    SciTech Connect (OSTI)

    Rhudy, R.

    1988-09-01

    Recent pilot plant tests indicate that spray drying, now used to control SO/sub 2/ emissions from low-sulfur coal, can also be effective for high-sulfur coal. Spray drying coupled with baghouse particulate removal is the most effective configuration tested to date, removing over 90% of SO/sub 2/ while easily meeting New Source Performance Standards for particulate emissions. 2 figures, 1 table.

  17. World copper smelter sulfur balance-1988

    SciTech Connect (OSTI)

    Towle, S.W. )

    1993-01-01

    In 1989, the US Bureau of Mines initiated a contract to gather engineering, operating, and environmental cost data for 1988 for 30 major foreign primary copper smelters in market economy countries. Data were collected for 29 of the designated smelters together with information on applicable environmental regulations. Materials balance data obtained were used with available data for the eight US smelters to determine the approximate extent of copper smelter sulfur emission control in 1988. A broad characterization of the status of sulfur emission control regulation was made. The 37 US and foreign smelters represented roughly 73.2% of world and 89.3% of market economy primary copper production in 1988. The 29 non-US smelters attained 55.3% control of their input sulfur in 1988. Combined with the 90.4% control of US smelters, an aggregate 63.4% sulfur control existed. Roughly 1,951,100 mt of sulfur was emitted from the 37 market economy smelters in 1988. Identifiable SO[sub 2] control regulations covered 72.4% of the 29 foreign smelters, representing 65.5% of smelting capacity. Including US smelters, 78.4% of the major market economy smelters were regulated, representing 73.1% of smelting capacity. Significant changes since 1988 that may increase sulfur emission control are noted.

  18. Development and testing of a PEM SO2-depolarized electrolyzer and an operating method that prevents sulfur accumulation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Steimke, John L.; Steeper, Timothy J.; Colon-Mercado, Hector R.; Gorensek, Maximilian B.

    2015-09-02

    The hybrid sulfur (HyS) cycle is being developed as a technology to generate hydrogen by splitting water, using heat and electrical power from a nuclear or solar power plant. A key component is the SO2-depolarized electrolysis (SDE) cell, which reacts SO2 and water to form hydrogen and sulfuric acid. SDE could also be used in once-through operation to consume SO2 and generate hydrogen and sulfuric acid for sale. A proton exchange membrane (PEM) SDE cell based on a PEM fuel cell design was fabricated and tested. Measured cell potential as a function of anolyte pressure and flow rate, sulfuric acidmore » concentration, and cell temperature are presented for this cell. Sulfur accumulation was observed inside the cell, which could have been a serious impediment to further development. A method to prevent sulfur formation was subsequently developed. As a result, this was made possible by a testing facility that allowed unattended operation for extended periods.« less

  19. Low Quality Natural Gas Sulfur Removal and Recovery CNG Claus Sulfur Recovery Process

    SciTech Connect (OSTI)

    Klint, V.W.; Dale, P.R.; Stephenson, C.

    1997-10-01

    Increased use of natural gas (methane) in the domestic energy market will force the development of large non-producing gas reserves now considered to be low quality. Large reserves of low quality natural gas (LQNG) contaminated with hydrogen sulfide (H{sub 2}S), carbon dioxide (CO{sub 2}) and nitrogen (N) are available but not suitable for treatment using current conventional gas treating methods due to economic and environmental constraints. A group of three technologies have been integrated to allow for processing of these LQNG reserves; the Controlled Freeze Zone (CFZ) process for hydrocarbon / acid gas separation; the Triple Point Crystallizer (TPC) process for H{sub 2}S / C0{sub 2} separation and the CNG Claus process for recovery of elemental sulfur from H{sub 2}S. The combined CFZ/TPC/CNG Claus group of processes is one program aimed at developing an alternative gas treating technology which is both economically and environmentally suitable for developing these low quality natural gas reserves. The CFZ/TPC/CNG Claus process is capable of treating low quality natural gas containing >10% C0{sub 2} and measurable levels of H{sub 2}S and N{sub 2} to pipeline specifications. The integrated CFZ / CNG Claus Process or the stand-alone CNG Claus Process has a number of attractive features for treating LQNG. The processes are capable of treating raw gas with a variety of trace contaminant components. The processes can also accommodate large changes in raw gas composition and flow rates. The combined processes are capable of achieving virtually undetectable levels of H{sub 2}S and significantly less than 2% CO in the product methane. The separation processes operate at pressure and deliver a high pressure (ca. 100 psia) acid gas (H{sub 2}S) stream for processing in the CNG Claus unit. This allows for substantial reductions in plant vessel size as compared to conventional Claus / Tail gas treating technologies. A close integration of the components of the CNG Claus

  20. Speciation of technetium peroxo complexes in sulfuric acid revisited

    SciTech Connect (OSTI)

    Poineau, Frederic; German, Konstantin E.; Burton-Pye, Benjamin P.; Weck, Philippe F.; Kim, Eunja; Kriyzhovets, Olga; Safonov, Aleksey; Ilin, Viktor; Francesconi, Lynn C.; Sattelberger, Alfred P.; Czerwinski, Kenneth R.

    2014-08-24

    We found that the reaction of Tc(+7) with H2O2 has been studied in H2SO4 and the speciation of technetium performed by UV–visible and 99-Tc NMR spectroscopy. UV–visible measurements show that for H2SO4 ≥ 9 M and H2O2 = 0.17 M, TcO3(OH)(H2O)2 reacts immediately and blue solutions are obtained, while no reaction occurs for H2SO42SO44 - begins to react for H2O2 = 2.12 M and red solutions are obtained. The UV–visible spectra of the red species are identical to the one obtained from the reaction of TcO4 - with H2O2 in HNO3 and consistent with the presence of TcO(O2)2(H2O)(OH). The 99-Tc NMR spectrum of the red solution exhibits a broad signal centered at +5.5 ppm vs TcO4 - and is consistent with the presence of a low symmetry Tc(+7) molecule.

  1. Speciation of technetium peroxo complexes in sulfuric acid revisited

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Poineau, Frederic; German, Konstantin E.; Burton-Pye, Benjamin P.; Weck, Philippe F.; Kim, Eunja; Kriyzhovets, Olga; Safonov, Aleksey; Ilin, Viktor; Francesconi, Lynn C.; Sattelberger, Alfred P.; et al

    2014-08-24

    We found that the reaction of Tc(+7) with H2O2 has been studied in H2SO4 and the speciation of technetium performed by UV–visible and 99-Tc NMR spectroscopy. UV–visible measurements show that for H2SO4 ≥ 9 M and H2O2 = 0.17 M, TcO3(OH)(H2O)2 reacts immediately and blue solutions are obtained, while no reaction occurs for H2SO42SO44 - begins to react for H2O2 = 2.12 M and red solutions are obtained. The UV–visible spectra of the red species are identical to the one obtained from the reaction of TcO4 - with H2O2 in HNO3 and consistent with the presence of TcO(O2)2(H2O)(OH). The 99-Tcmore » NMR spectrum of the red solution exhibits a broad signal centered at +5.5 ppm vs TcO4 - and is consistent with the presence of a low symmetry Tc(+7) molecule.« less

  2. Direct Observation of Sulfur Radicals as Reaction Media in Lithium Sulfur Batteries

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Qiang; Zheng, Jianming; Walter, Eric; Pan, Huilin; Lv, Dongping; Zuo, Pengjian; Chen, Honghao; Deng, Z. D.; Liaw, Bor Y.; Yu, Xiqian; et al

    2015-01-09

    Lithium sulfur (Li-S) battery has been regaining tremendous interest in recent years because of its attractive attributes such as high gravimetric energy, low cost and environmental benignity. However, it is still not conclusively known how polysulfide ring/chain participates in the whole cycling and whether the discharge and charge processes follow the same pathway. Herein, we demonstrate the direct observation of sulfur radicals by using in situ electron paramagnetic resonance (EPR) technique. Based on the concentration changes of sulfur radicals at different potentials and the electrochemical characteristics of the cell, it is revealed that the chemical and electrochemical reactions in Li-Smore » cell are driving each other to proceed through sulfur radicals, leading to two completely different reaction pathways during discharge and charge. The proposed radical mechanism may provide new perspectives to investigate the interactions between sulfur species and the electrolyte, inspiring novel strategies to develop Li-S battery technology.« less

  3. Direct Observation of Sulfur Radicals as Reaction Media in Lithium Sulfur Batteries

    SciTech Connect (OSTI)

    Wang, Qiang; Zheng, Jianming; Walter, Eric; Pan, Huilin; Lv, Dongping; Zuo, Pengjian; Chen, Honghao; Deng, Z. D.; Liaw, Bor Y.; Yu, Xiqian; Yang, Xiao-Qing; Zhang, Ji-Guang; Liu, Jun; Xiao, Jie

    2015-01-09

    Lithium sulfur (Li-S) battery has been regaining tremendous interest in recent years because of its attractive attributes such as high gravimetric energy, low cost and environmental benignity. However, it is still not conclusively known how polysulfide ring/chain participates in the whole cycling and whether the discharge and charge processes follow the same pathway. Herein, we demonstrate the direct observation of sulfur radicals by using in situ electron paramagnetic resonance (EPR) technique. Based on the concentration changes of sulfur radicals at different potentials and the electrochemical characteristics of the cell, it is revealed that the chemical and electrochemical reactions in Li-S cell are driving each other to proceed through sulfur radicals, leading to two completely different reaction pathways during discharge and charge. The proposed radical mechanism may provide new perspectives to investigate the interactions between sulfur species and the electrolyte, inspiring novel strategies to develop Li-S battery technology.

  4. Electrostatic self-assembly of graphene oxide wrapped sulfur particles for lithium–sulfur batteries

    SciTech Connect (OSTI)

    Wu, Haiwei; Huang, Ying Zong, Meng; Ding, Xiao; Ding, Juan; Sun, Xu

    2015-04-15

    Highlights: • Researched graphene oxide wrapped sulfur particles for lithium–sulfur batteries. • New approach for core–shell GO/S composites by electrostatic self-assembly method. • Both core–shell structure and the GO support help to retard the diffusion of polysulfides during the electrochemical cycling process of GO/S cathode. - Abstract: A novel graphene oxide (GO)/sulfur (S) composite is developed by electrostatic self-assembly method. Remarkably, the core–shell structure of the composite and the GO support helps to retard the diffusion of polysulfides during the electrochemical cycling process. The GO/sulfur cathode presents enhanced cycling ability. Specific discharge capacities up to 494.7 mAh g{sup −1} over 200 cycles at 0.1 C is achieved with enhanced columbic efficiency around 95%, representing a good cathode material for lithium–sulfur batteries.

  5. Direct Observation of Sulfur Radicals as Reaction Media in lithium Sulfur Batteries

    SciTech Connect (OSTI)

    Wang, Qiang; Zheng, Jianming; Walter, Eric D.; Pan, Huilin; Lu, Dongping; Zuo, Pengjian; Chen, Honghao; Deng, Zhiqun; Liaw, Bor Yann; Yu, Xiqian; Yang, Xiaoning; Zhang, Jiguang; Liu, Jun; Xiao, Jie

    2014-12-09

    Lithium sulfur (Li-S) battery has been regaining tremendous interest in recent years because of its attractive attributes such as high gravimetric energy, low cost and environmental benignity. However, it is still not conclusively known how polysulfide ring/chain participates in the whole cycling and whether the discharge and charge process follow the same pathway. Herein, we demonstrate the direct observation of sulfur radicals by using in situ electron paramagnetic resonance (EPR) technique. Based on the concentration changes of sulfur radicals at different potentials, it is revealed that the chemical and electrochemical reactions in Li-S cell are driven each other to proceed through sulfur radicals, leading to two completely different reaction pathways during discharge and charge. The proposed radical mechanism may provide new insights to investigate the interactions between sulfur species and the electrolyte, inspiring novel strategies to develop Li-S battery technology.

  6. Effect of sulfur content in a sulfur-activated carbon composite on the electrochemical properties of a lithium/sulfur battery

    SciTech Connect (OSTI)

    Park, Jin-Woo; Kim, Changhyeon; Ryu, Ho-Suk; Cho, Gyu-Bong; Cho, Kwon-Koo; Kim, Ki-Won; Ahn, Jou-Hyeon; Wang, Guoxiu; Ahn, Jae-Pyeung; Ahn, Hyo-Jun

    2015-09-15

    Highlights: • The content of sulfur in activated carbon was controlled by solution process. • The sulfur electrode with low sulfur content shows the best performance. • The Li/S battery has capacity of 1360 mAh/g at 1 C and 702 mAh/g at 10 C. - Abstract: The content of sulfur in sulfur/activated carbon composite is controlled from 32.37 wt.% to 55.33 wt.% by a one-step solution-based process. When the sulfur content is limited to 41.21 wt.%, it can be loaded into the pores of an activated carbon matrix in a highly dispersed state. On the contrary, when the sulfur content is 55.33 wt.%, crystalline sulfur can be detected on the surface of the activated carbon matrix. The best electrochemical performance can be obtained for a sulfur electrode with the lowest sulfur content. The sulfur/activated carbon composite with 32.37 wt.% sulfur afforded the highest first discharge capacity of 1360 mAh g{sup −1} at 1 C rate and a large reversible capacity of 702 mAh g{sup −1} at 10 C (16.75 A/g)

  7. Carbon/Sulfur Nanocomposites and Additives for High-Energy Lithium...

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

    Additives and Cathode Materials for High-Energy Lithium Sulfur Batteries CarbonSulfur Nanocomposites and Additives for High-Energy Lithium Sulfur Batteries Vehicle Technologies ...

  8. Carbon/Sulfur Nanocomposites and Additives for High-Energy Lithium...

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

    CarbonSulfur Nanocomposites and Additives for High-Energy Lithium Sulfur Batteries Additives and Cathode Materials for High-Energy Lithium Sulfur Batteries Protection of Li Anodes ...

  9. Dilution cycle control for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C.

    1984-01-01

    A dilution cycle control system for an absorption refrigeration system is disclosed. The control system includes a time delay relay for sensing shutdown of the absorption refrigeration system and for generating a control signal only after expiration of a preselected time period measured from the sensed shutdown of the absorption refrigeration system, during which the absorption refrigeration system is not restarted. A dilution cycle for the absorption refrigeration system is initiated in response to generation of a control signal by the time delay relay. This control system is particularly suitable for use with an absorption refrigeration system which is frequently cycled on and off since the time delay provided by the control system prevents needless dilution of the absorption refrigeration system when the system is turned off for only a short period of time and then is turned back on.

  10. Process of concentrating ethanol from dilute aqueous solutions thereof

    DOE Patents [OSTI]

    Oulman, Charles S. [Ames, IA; Chriswell, Colin D. [Slater, IA

    1981-07-07

    Relatively dilute aqueous solutions of ethanol are concentrated by passage through a bed of a crystalline silica polymorph, such as silicalite, to adsorb the ethanol with residual dilute feed in contact with the bed, which is displaced by passing concentrated aqueous ethanol through the bed without displacing the adsorbed ethanol. A product concentrate is then obtained by removing the adsorbed ethanol from the bed together with at least a portion of the concentrated aqueous ethanol used as the displacer liquid. This process permits ethanol to be concentrated from dilute fermentation beers, which may contain from 6 to 10% ethanol, to obtain a concentrate product at very low energy cost having an ethanol concentration in excess of 95%, such as a concentration of from 98 to 99.5%.

  11. Process of concentrating ethanol from dilute aqueous solutions thereof

    DOE Patents [OSTI]

    Oulman, C.S.; Chriswell, C.D.

    1981-07-07

    Relatively dilute aqueous solutions of ethanol are concentrated by passage through a bed of a crystalline silica polymorph, such as silicalite, to adsorb the ethanol with residual dilute feed in contact with the bed, which is displaced by passing concentrated aqueous ethanol through the bed without displacing the adsorbed ethanol. A product concentrate is then obtained by removing the adsorbed ethanol from the bed together with at least a portion of the concentrated aqueous ethanol used as the displacer liquid. This process permits ethanol to be concentrated from dilute fermentation beers, which may contain from 6 to 10% ethanol, to obtain a concentrate product at very low energy cost having an ethanol concentration in excess of 95%, such as a concentration of from 98 to 99.5%. 5 figs.

  12. Rapid separation and purification of uranium and plutonium from dilute-matrix samples

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Armstrong, Christopher R.; Ticknor, Brian W.; Hall, Gregory; Cadieux, James R.

    2014-03-11

    This work presents a streamlined separation and purification approach for trace uranium and plutonium from dilute (carrier-free) matrices. The method, effective for nanogram quantities of U and femtogram to picogram quantities of Pu, is ideally suited for environmental swipe samples that contain a small amount of collected bulk material. As such, it may be applicable for processing swipe samples such as those collected in IAEA inspection activities as well as swipes that are loaded with unknown analytes, such as those implemented in interlaboratory round-robin or proficiency tests. Additionally, the simplified actinide separation could find use in internal laboratory monitoring ofmore » clean room conditions prior to or following more extensive chemical processing. We describe key modifications to conventional techniques that result in a relatively rapid, cost-effective, and efficient U and Pu separation process. We demonstrate the efficacy of implementing anion exchange chromatography in a single column approach. We also show that hydrobromic acid is an effective substitute in lieu of hydroiodoic acid for eluting Pu. Lastly, we show that nitric acid is an effective digestion agent in lieu of perchloric acid and/or hydrofluoric acid. A step by step procedure of this process is detailed.« less

  13. Rapid separation and purification of uranium and plutonium from dilute-matrix samples

    SciTech Connect (OSTI)

    Armstrong, Christopher R.; Ticknor, Brian W.; Hall, Gregory; Cadieux, James R.

    2014-03-11

    This work presents a streamlined separation and purification approach for trace uranium and plutonium from dilute (carrier-free) matrices. The method, effective for nanogram quantities of U and femtogram to picogram quantities of Pu, is ideally suited for environmental swipe samples that contain a small amount of collected bulk material. As such, it may be applicable for processing swipe samples such as those collected in IAEA inspection activities as well as swipes that are loaded with unknown analytes, such as those implemented in interlaboratory round-robin or proficiency tests. Additionally, the simplified actinide separation could find use in internal laboratory monitoring of clean room conditions prior to or following more extensive chemical processing. We describe key modifications to conventional techniques that result in a relatively rapid, cost-effective, and efficient U and Pu separation process. We demonstrate the efficacy of implementing anion exchange chromatography in a single column approach. We also show that hydrobromic acid is an effective substitute in lieu of hydroiodoic acid for eluting Pu. Lastly, we show that nitric acid is an effective digestion agent in lieu of perchloric acid and/or hydrofluoric acid. A step by step procedure of this process is detailed.

  14. Method of making a sodium sulfur battery

    DOE Patents [OSTI]

    Elkins, P. E.

    1981-09-22

    A method of making a portion of a sodium sulfur battery is disclosed. The battery portion made is a portion of the container which defines the volume for the cathodic reactant materials which are sulfur and sodium polysulfide materials. The container portion is defined by an outer metal casing with a graphite liner contained therein, the graphite liner having a coating on its internal diameter for sealing off the porosity thereof. The steel outer container and graphite pipe are united by a method which insures that at the operating temperature of the battery, relatively low electrical resistance exists between the two materials because they are in intimate contact with one another. 3 figs.

  15. Method of making a sodium sulfur battery

    DOE Patents [OSTI]

    Elkins, Perry E.

    1981-01-01

    A method of making a portion of a sodium sulfur battery is disclosed. The battery portion made is a portion of the container which defines the volume for the cathodic reactant materials which are sulfur and sodium polysulfide materials. The container portion is defined by an outer metal casing with a graphite liner contained therein, the graphite liner having a coating on its internal diameter for sealing off the porosity thereof. The steel outer container and graphite pipe are united by a method which insures that at the operating temperature of the battery, relatively low electrical resistance exists between the two materials because they are in intimate contact with one another.

  16. Effect of Sulfur on Solid Oxide Fuel Cell (SOFC) Performance...

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

    Effect of Sulfur on SOFC Performance Using Diesel Reformate R. Kerr March 6-7, 2014 Workshop on Gas Cleanup for Fuel Cell Applications, ANL, March 6-7, 2014 Sulfur Poisoning Effect ...

  17. EPA Diesel Rule and the Sulfur Effects (DECSE) Project

    SciTech Connect (OSTI)

    2009-05-08

    The VT program collaborated with industry stakeholders and the EPA (in an effort initiated in 1998 called Diesel Emission Control – Sulfur Effects study, otherwise known as DECSE) to quantify the effects of fuel sulfur on emission control technologies.

  18. Development of a new FGD process that converts sulfur dioxide to salable ammonium phosphate fertilizer

    SciTech Connect (OSTI)

    Ji-lu Chen

    1993-12-31

    Rich mineral resources have enabled Chinese coal output and energy consumption to rank second and third in the world, respectively. In 1992, up to 70 percent of the country`s electric power was generated by the combustion of some 300 million tons of coal. Although the average sulfur content level in Chinese coals is only about 0.8 percent, the share of high- sulfur coals with 2 percent or more sulfur content is as high as 18 percent. As a result, air pollution accompanied by acid rain now occurs over most of the country, especially in southwestern China. Currently, the area comprising Guangdong, Guangxi, the Sichuan Basin, and the greater part of Gueizhou, where the sulfur content in coal is between 2 and 7 percent and the average pH values of rain water are between 4 and 5 per annum, has become one of the three biggest acid rain-affected areas in the world. In 1992, the national installed coal-fired electricity generation capacity exceeded 100,000 MWe. By the year 2000, it is expected to reach as much as 200,000 MWe, according to a new scheduled program. Environmental pollution caused by large-scale coal combustion is a very important issue that needs to be considered in the implementation of the program. To ensure that the effects of coal-fired power generation on the environment can be properly controlled in the near future, TPRI (Thermal Power Research Institute), the sole thermal power engineering research institution within the Ministry of Electric Power Industry (MOEPI), has conducted a long-term research program to develop sulfur emission control technologies suitable to the special conditions prevalent in China since the early 1970s. The details are summarized. The objective of this chapter is to describe the fundamental concept and major pilot test results and present an economic evaluation of a new process combining flue gas desulfurization (FGD) and ammonium phosphate fertilizer production.

  19. Anodes for Rechargeable Lithium-Sulfur Batteries

    SciTech Connect (OSTI)

    Cao, Ruiguo; Xu, Wu; Lu, Dongping; Xiao, Jie; Zhang, Jiguang

    2015-04-10

    In this work, we will review the recent developments on the protection of Li metal anode in Li-S batteries. Various strategies used to minimize the corrosion of Li anode and reducing its impedance increase will be analyzed. Other potential anodes used in sulfur based rechargeable batteries will also be discussed.

  20. Process for removing sulfur from sulfur-containing gases: high calcium fly-ash

    DOE Patents [OSTI]

    Rochelle, Gary T.; Chang, John C. S.

    1991-01-01

    The present disclosure relates to improved processes for treating hot sulfur-containing flue gas to remove sulfur therefrom. Processes in accordance with the present invention include preparing an aqueous slurry composed of a calcium alkali source and a source of reactive silica and/or alumina, heating the slurry to above-ambient temperatures for a period of time in order to facilitate the formation of sulfur-absorbing calcium silicates or aluminates, and treating the gas with the heat-treated slurry components. Examples disclosed herein demonstrate the utility of these processes in achieving improved sulfur-absorbing capabilities. Additionally, disclosure is provided which illustrates preferred configurations for employing the present processes both as a dry sorbent injection and for use in conjunction with a spray dryer and/or bagfilter. Retrofit application to existing systems is also addressed.

  1. Development and testing of a PEM SO2-depolarized electrolyzer and an operating method that prevents sulfur accumulation

    SciTech Connect (OSTI)

    Steimke, John L.; Steeper, Timothy J.; Colon-Mercado, Hector R.; Gorensek, Maximilian B.

    2015-09-02

    The hybrid sulfur (HyS) cycle is being developed as a technology to generate hydrogen by splitting water, using heat and electrical power from a nuclear or solar power plant. A key component is the SO2-depolarized electrolysis (SDE) cell, which reacts SO2 and water to form hydrogen and sulfuric acid. SDE could also be used in once-through operation to consume SO2 and generate hydrogen and sulfuric acid for sale. A proton exchange membrane (PEM) SDE cell based on a PEM fuel cell design was fabricated and tested. Measured cell potential as a function of anolyte pressure and flow rate, sulfuric acid concentration, and cell temperature are presented for this cell. Sulfur accumulation was observed inside the cell, which could have been a serious impediment to further development. A method to prevent sulfur formation was subsequently developed. As a result, this was made possible by a testing facility that allowed unattended operation for extended periods.

  2. System for agitating the acid in a lead-acid battery

    DOE Patents [OSTI]

    Weintraub, Alvin; MacCormack, Robert S.

    1987-01-01

    A system and method for agitating the acid in a large lead-sulfuric acid storage battery of the calcium type. An air-lift is utilized to provide the agitation. The air fed to the air-lift is humidified prior to being delivered to the air-lift.

  3. Tailoring Pore Size of Nitrogen-Doped Hollow Carbon Nanospheres for Confi ning Sulfur in LithiumSulfur Batteries

    SciTech Connect (OSTI)

    Zhou, Weidong; Wang, Chong M.; Zhang, Quiglin; Abruna, Hector D.; He, Yang; Wang, Jiangwei; Mao, Scott X.; Xiao, Xingcheng

    2015-08-19

    Three types of nitrogen-doped hollow carbon spheres with different pore sized porous shells are prepared to investigate the performance of sulfur confinement. The reason that why no sulfur is observed in previous research is determined and it is successfully demonstrated that the sulfur/polysulfide will overflow the porous carbon during the lithiation process.

  4. Method to prevent sulfur accumulation in membrane electrode assembly

    DOE Patents [OSTI]

    Steimke, John L; Steeper, Timothy J; Herman, David T

    2014-04-29

    A method of operating a hybrid sulfur electrolyzer to generate hydrogen is provided that includes the steps of providing an anolyte with a concentration of sulfur dioxide, and applying a current. During steady state generation of hydrogen a plot of applied current density versus concentration of sulfur dioxide is below a boundary line. The boundary line may be linear and extend through the origin of the graph with a slope of 0.001 in which the current density is measured in mA/cm2 and the concentration of sulfur dioxide is measured in moles of sulfur dioxide per liter of anolyte.

  5. Fuel-rich sulfur capture in a combustion environment

    SciTech Connect (OSTI)

    Lindgren, E.R.; Pershing, D.W.; Kirchgessner, D.A.; Drehmel, D.C.

    1992-01-01

    The paper discusses the use of a refactory-lined, natural gas furnace to study the fuel-rich sulfur capture reactions of calcium sorbents under typical combustion conditions. The fuel-rich sulfur species hydrogen sulfide and carbonyl sulfide were monitored in a nearly continuous fashion using a gas chromatograph equiped with a flame photometric detector and an automatic system that sampled every 30 seconds. Below the fuel-rich zone, 25% excess air was added, and the ultimate fuel-lean capture was simultaneously measured using a continuous sulfur dioxide monitor. Under fuel-rich conditions, high levels of sulfur capture were obtained, and calcium utilization increased with sulfur concentration. The ultimate lean capture was found to be weakly dependent on sulfur concentration and independent of the sulfur capture level obtained in the fuel-rich zone.

  6. Critical dynamics of cluster algorithms in the dilute Ising model

    SciTech Connect (OSTI)

    Hennecke, M. Universitaet Karlsruhe ); Heyken, U. )

    1993-08-01

    Autocorrelation times for thermodynamic quantities at [Tc] are calculated from Monte Carlo simulations of the site-diluted simple cubic Ising model, using the Swendsen-Wand and Wolff cluster algorithms. The results show that for these algorithms the autocorrelation times decrease when reducing the concentration of magnetic sites from 100% down to 40%. This is of crucial importance when estimating static properties of the model, since the variances of these estimators increase with autocorrelation time. The dynamical critical exponents are calculated for both algorithms, observing pronounced finite-size effects in the energy autocorrelation data for the algorithm of Wolff. It is concluded that, when applied to the dilute Ising model, cluster algorithms become even more effective than local algorithms, for which increasing autocorrelation times are expected. 33 refs., 5 figs., 2 tabs.

  7. Separation and concentration of lower alcohols from dilute aqueous solutions

    DOE Patents [OSTI]

    Moore, Raymond H.; Eakin, David E.; Baker, Eddie G.; Hallen, Richard T.

    1991-01-01

    A process for producing, from a dilute aqueous solution of a lower (C.sub.1 -C.sub.5) alcohol, a concentrated liquid solution of the alcohol in an aromatic organic solvent is disclosed. Most of the water is removed from the dilute aqueous solution of alcohol by chilling sufficiently to form ice crystals. Simultaneously, the remaining liquid is extracted at substantially the same low temperature with a liquid organic solvent that is substantially immiscible in aqueous liquids and has an affinity for the alcohol at that temperature, causing the alcohol to transfer to the organic phase. After separating the organic liquid from the ice crystals, the organic liquid can be distilled to enrich the concentration of alcohol therein. Ethanol so separated from water and concentrated in an organic solvent such as toluene is useful as an anti-knock additive for gasoline.

  8. Dilution calculations for determining laboratory exhaust stack heights

    SciTech Connect (OSTI)

    Ratcliff, M.A.; Sandru, E.

    1999-07-01

    Laboratory exhaust stacks should be designed with sufficient height and exit momentum to avoid re-entry of exhaust and possible air quality problems, and the design should be evaluated before construction. One evaluation method is presented in this paper that combines dilution prediction equations from the 1997 ASHRAE Handbook--Fundamentals (1997) and a dilution criteria of Halitsky (1988). This method is less conservative than a geometric method in the ASHRAE Handbook and is less costly than wind-tunnel modeling. The method should only be applied to relatively simple building geometries with no larger buildings adjacent to them. A planned change to the ASHRAE equations, which would result in larger stacks being necessary, is discussed. Further investigation of this change is recommended using comparisons to wind tunnel data.

  9. The effects of dilution on turbulence and transport in C-Mod...

    Office of Scientific and Technical Information (OSTI)

    The effects of dilution on turbulence and transport in C-Mod ohmic plasmas and comparisons ... Title: The effects of dilution on turbulence and transport in C-Mod ohmic plasmas and ...

  10. Simultaneously Low-Engine-Out NOx and PM with Highly Diluted...

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

    Simultaneously Low-Engine-Out NOx and PM with Highly Diluted Diesel Combustuion Simultaneously Low-Engine-Out NOx and PM with Highly Diluted Diesel Combustuion 2002 DEER Conference ...

  11. Catalyst for elemental sulfur recovery process

    DOE Patents [OSTI]

    Flytzani-Stephanopoulos, Maria; Liu, Wei

    1995-01-01

    A catalytic reduction process 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: [(OF.sub.2).sub.1-n (RO.sub.1)n].sub.1-k M.sub.k, [(FO.sub.2).sub.1-n (RO.sub.1.5).sub.n ].sub.1-k M.sub.k, or [Ln.sub.x Zr.sub.1-x O.sub.2-0.5x ].sub.1-k M.sub.k wherein FO.sub.2 is a fluorite-type oxide; RO represents an alkaline earth oxide; RO.sub.1.5 is a Group IIIB or rare earth oxide; Ln is a rare earth element having an atomic number from 57 to 65 or mixtures thereof; M is a transition metal or a mixture of transition metals; n is a number having a value from 0.0 to 0.35; k is a number having a value from 0.0 to about 0.5; and x is a number having a value from about 0.45 to about 0.55.

  12. HYBRID SULFUR FLOWSHEETS USING PEM ELECTROLYSIS AND A BAYONET DECOMPOSITION REACTOR

    SciTech Connect (OSTI)

    Gorensek, M; William Summers, W

    2008-05-30

    A conceptual design is presented for a Hybrid Sulfur process for the production of hydrogen using a high-temperature nuclear heat source to split water. The process combines proton exchange membrane-based SO{sub 2}-depolarized electrolyzer technology being developed at Savannah River National Laboratory with silicon carbide bayonet decomposition reactor technology being developed at Sandia National Laboratories. Both are part of the US DOE Nuclear Hydrogen Initiative. The flowsheet otherwise uses only proven chemical process components. Electrolyzer product is concentrated from 50 wt% sulfuric acid to 75 wt% via recuperative vacuum distillation. Pinch analysis is used to predict the high-temperature heat requirement for sulfuric acid decomposition. An Aspen Plus{trademark} model of the flowsheet indicates 340.3 kJ high-temperature heat, 75.5 kJ low-temperature heat, 1.31 kJ low-pressure steam, and 120.9 kJ electric power are consumed per mole of H{sub 2} product, giving an LHV efficiency of 35.3% (41.7% HHV efficiency) if electric power is available at a conversion efficiency of 45%.

  13. Comparison of environmental and isolate Sulfobacillus genomes reveals diverse carbon, sulfur, nitrogen, and hydrogen metabolisms

    SciTech Connect (OSTI)

    Justice, Nicholas B.; Norman, Anders; Brown, Christopher T.; Singh, Andrea; Thomas, Brian C.; Banfield, Jillian F.

    2014-12-15

    Bacteria of the genus Sulfobacillus are found worldwide as members of microbial communities that accelerate sulfide mineral dissolution in acid mine drainage environments (AMD), acid-rock drainage environments (ARD), as well as in industrial bioleaching operations. Despite their frequent identification in these environments, their role in biogeochemical cycling is poorly understood. Here we report draft genomes of five species of the Sulfobacillus genus (AMDSBA1-5) reconstructed by cultivation-independent sequencing of biofilms sampled from the Richmond Mine (Iron Mountain, CA). Three of these species (AMDSBA2, AMDSBA3, and AMDSBA4) have no cultured representatives while AMDSBA1 is a strain of S. benefaciens, and AMDSBA5 a strain of S. thermosulfidooxidans. We analyzed the diversity of energy conservation and central carbon metabolisms for these genomes and previously published Sulfobacillus genomes. Pathways of sulfur oxidation vary considerably across the genus, including the number and type of subunits of putative heterodisulfide reductase complexes likely involved in sulfur oxidation. The number and type of nickel-iron hydrogenase proteins varied across the genus, as does the presence of different central carbon pathways. Only the AMDSBA3 genome encodes a dissimilatory nitrate reducatase and only the AMDSBA5 and S. thermosulfidooxidans genomes encode assimilatory nitrate reductases. Lastly, within the genus, AMDSBA4 is unusual in that its electron transport chain includes a cytochrome bc type complex, a unique cytochrome c oxidase, and two distinct succinate dehydrogenase complexes. Overall, the results significantly expand our understanding of carbon, sulfur, nitrogen, and hydrogen metabolism within the Sulfobacillus genus.

  14. Nitrogen and Sulfur Requirements for Clostridium thermocellum and Caldicellulosiruptor bescii on Cellulosic Substrates in Minimal Nutrient Media

    SciTech Connect (OSTI)

    Kridelbaugh, Donna M; Nelson, Josh C; Engle, Nancy L; Tschaplinski, Timothy J; Graham, David E

    2013-01-01

    Growth media for cellulolytic Clostridium thermocellum and Caldicellulosiruptor bescii bacteria usually contain excess nutrients that would increase costs for consolidated bioprocessing for biofuel production and create a waste stream with nitrogen, sulfur and phosphate. C. thermocellum was grown on crystalline cellulose with varying concentrations of nitrogen and sulfur compounds, and growth rate and alcohol production response curves were determined. Both bacteria assimilated sulfate in the presence of ascorbate reductant, increasing the ratio of oxidized to reduced fermentation products. From these results, a low ionic strength, defined minimal nutrient medium with decreased nitrogen, sulfur, phosphate and vitamin supplements was developed for the fermentation of cellobiose, cellulose and acid-pretreated Populus. Carbon and electron balance calculations indicate the unidentified residual fermentation products must include highly reduced molecules. Both bacterial populations were maintained in co-cultures with substrates containing xylan or hemicellulose in defined medium with sulfate and basal vitamin supplements.

  15. Sodium/sulfur battery engineering for stationary energy storage. Final report

    SciTech Connect (OSTI)

    Koenig, A.; Rasmussen, J.

    1996-04-01

    The use of modular systems to distribute power using batteries to store off-peak energy and a state of the art power inverter is envisioned to offer important national benefits. A 4-year, cost- shared contract was performed to design and develop a modular, 300kVA/300-kWh system for utility and customer applications. Called Nas-P{sub AC}, this system uses advanced sodium/sulfur batteries and requires only about 20% of the space of a lead-acid-based system with a smaller energy content. Ten, 300-VDC, 40-kWh sodium/sulfur battery packs are accommodated behind a power conversion system envelope with integrated digital control. The resulting design facilities transportation, site selection, and deployment because the system is quiet and non-polluting, and can be located in proximity to the load. This report contains a detailed description of the design and supporting hardware development performed under this contract.

  16. Process for production of synthesis gas with reduced sulfur content

    DOE Patents [OSTI]

    Najjar, Mitri S.; Corbeels, Roger J.; Kokturk, Uygur

    1989-01-01

    A process for the partial oxidation of a sulfur- and silicate-containing carbonaceous fuel to produce a synthesis gas with reduced sulfur content which comprises partially oxidizing said fuel at a temperature in the range of 1800.degree.-2200.degree. F. in the presence of a temperature moderator, an oxygen-containing gas and a sulfur capture additive which comprises an iron-containing compound portion and a sodium-containing compound portion to produce a synthesis gas comprising H.sub.2 and CO with a reduced sulfur content and a molten slag which comprises (i) a sulfur-containing sodium-iron silicate phase and (ii) a sodium-iron sulfide phase. The sulfur capture additive may optionally comprise a copper-containing compound portion.

  17. Sulfur control in ion-conducting membrane systems

    DOE Patents [OSTI]

    Stein, VanEric Edward; Richards, Robin Edward; Brengel, David Douglas; Carolan, Michael Francis

    2003-08-05

    A method for controlling the sulfur dioxide partial pressure in a pressurized, heated, oxygen-containing gas mixture which is contacted with an ion-conducting metallic oxide membrane which permeates oxygen ions. The sulfur dioxide partial pressure in the oxygen-depleted non-permeate gas from the membrane module is maintained below a critical sulfur dioxide partial pressure, p.sub.SO2 *, to protect the membrane material from reacting with sulfur dioxide and reducing the oxygen flux of the membrane. Each ion-conducting metallic oxide material has a characteristic critical sulfur dioxide partial pressure which is useful in determining the required level of sulfur removal from the feed gas and/or from the fuel gas used in a direct-fired feed gas heater.

  18. Sulfur-impurity Induced Amorphization of Nickel | Argonne Leadership

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

    Computing Facility Sulfur-impurity Induced Amorphization of Nickel Authors: Yuan, Z., Chen, H.P, Wang, W., Nomura, K., Kalia, R.K., Nakano, A., Vashishta, P. Recent experimental and theoretical studies have shown an essential role of sulfur segregation-induced amorphization of crystalline nickel leading to its embrittlement at a critical sulfur concentration of ∼14%, but the atomistic mechanism of the amorphization remains unexplained. Here, molecular dynamics simulations reveal that the

  19. Removal of sulfur compounds from combustion product exhaust

    DOE Patents [OSTI]

    Cheng, Dah Y.

    1982-01-01

    A method and device are disclosed for removing sulfur containing contaminents from a combustion product exhaust. The removal process is carried out in two stages wherein the combustion product exhaust is dissolved in water, the water being then heated to drive off the sulfur containing contaminents. The sulfur containing gases are then resolublized in a cold water trap to form a concentrated solution which can then be used as a commercial product.

  20. Sparingly Solvating Electrolytes for High Energy Density Lithium-Sulfur

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

    Batteries - Joint Center for Energy Storage Research August 24, 2016, Videos Sparingly Solvating Electrolytes for High Energy Density Lithium-Sulfur Batteries As JCESR scientists work to develop lighter and less expensive chemistries than those used in current lithium-ion batteries, lithium-sulfur shows tremendous promise. However, current lithium-sulfur batteries require an excessive amount of electrolyte to achieve moderate cycle life. This perspective presents an alternate approach of

  1. Sulfide catalysts for reducing SO2 to elemental sulfur

    DOE Patents [OSTI]

    Jin, Yun; Yu, Qiquan; Chang, Shih-Ger

    2001-01-01

    A highly efficient sulfide catalyst for reducing sulfur dioxide to elemental sulfur, which maximizes the selectivity of elemental sulfur over byproducts and has a high conversion efficiency. Various feed stream contaminants, such as water vapor are well tolerated. Additionally, hydrogen, carbon monoxide, or hydrogen sulfides can be employed as the reducing gases while maintaining high conversion efficiency. This allows a much wider range of uses and higher level of feed stream contaminants than prior art catalysts.

  2. Project Profile: Baseload CSP Generation Integrated with Sulfur-Based

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

    Thermochemical Heat Storage | Department of Energy Baseload CSP Generation Integrated with Sulfur-Based Thermochemical Heat Storage Project Profile: Baseload CSP Generation Integrated with Sulfur-Based Thermochemical Heat Storage General Atomics logo General Atomics, under the Baseload CSP FOA, demonstrated the engineering feasibility of using a sulfur-based thermochemical cycle to store heat from a CSP plant and support baseload power generation. Approach Graphic of a diagram of squares and

  3. Synergistic Inhibitors for Dilute High-Level Radioactive Waste

    SciTech Connect (OSTI)

    Wiersma, B.J.; Zapp, P.E.

    1995-11-01

    Cyclic potentiodynamic polarization scans were conducted to determine the effectiveness of various combinations of anodic inhibitors in the prevention of pitting in carbon steel exposed to dilute radioactive waste. Chromate, molybdate, and phosphate were investigated as replacements for nitrite, whose effective concentrations are incompatible with the waste vitrification process. The polarization scans were performed in non-radioactive waste simulants. Their results showed that acceptable combinations of phosphate with chromate and phosphate with molybdate effectively prevented pitting corrosion. Chromate with molybdate could not replace nitrite.

  4. Extraction of Sulfur Mustard Metabolites from Urine Samples and...

    Office of Scientific and Technical Information (OSTI)

    Title: Extraction of Sulfur Mustard Metabolites from Urine Samples and Analysis by Liquid Chromatography-High-Resolution Mass Spectrometry (LC-HRMS) Authors: Mayer, B P ; Williams, ...

  5. Microsoft Word - Updated Air Dispersion Modeling Table _sulfur...

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

    DIVINE STRAKE AIR DISPERSION MODELING RESULTS for SULFUR DIOXIDE The attached table is ... within the Nevada Ambient Air Quality Standards at the boundary of the Nevada Test Site. ...

  6. Lithium/Sulfur Batteries Based on Doped Mesoporous Carbon - Energy...

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

    of doped mesoporous carbon and elemental sulfur at a temperature inside a stainless steel vessel, which was used in lithiumsulfur batteries that were tested in ...

  7. Project Profile: Baseload CSP Generation Integrated with Sulfur...

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

    Concentrating Solar Power Project Profile: Baseload CSP Generation Integrated with Sulfur-Based ... General Atomics is seeking a better thermal energy storage approach using ...

  8. Following the Transient Reactions in Lithium-Sulfur Batteries...

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

    Following the Transient Reactions in Lithium-Sulfur Batteries Using an In Situ Nuclear ... cell electrochemical reactions in Li-S batteries using a microbattery design Interphase ...

  9. Sulfur removal and comminution of carbonaceous material

    DOE Patents [OSTI]

    Narain, Nand K.; Ruether, John A.; Smith, Dennis N.

    1988-01-01

    Finely divided, clean coal or other carbonaceous material is provided by forming a slurry of coarse coal in aqueous alkali solution and heating the slurry under pressure to above the critical conditions of steam. The supercritical fluid penetrates and is trapped in the porosity of the coal as it swells in a thermoplastic condition at elevated temperature. By a sudden, explosive release of pressure the coal is fractured into finely divided particles with release of sulfur-containing gases and minerals. The finely divided coal is recovered from the minerals for use as a clean coal product.

  10. Sulfur removal and comminution of carbonaceous material

    DOE Patents [OSTI]

    Narain, N.K.; Ruether, J.A.; Smith, D.N.

    1987-10-07

    Finely divided, clean coal or other carbonaceous material is provided by forming a slurry of coarse coal in aqueous alkali solution and heating the slurry under pressure to above the critical conditions of steam. The supercritical fluid penetrates and is trapped in the porosity of the coal as it swells in a thermoplastic condition at elevated temperature. By a sudden, explosive release of pressure the coal is fractured into finely divided particles with release of sulfur-containing gases and minerals. The finely divided coal is recovered from the minerals for use as a clean coal product. 2 figs.