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Development of Kinetic Models for the Liquid Phase Methanol (LPMEOH tm) Process

Description: This report covers our recent work on the kinetics of the LPMEOH{trademark} process. The major part of the report concerns the development of more robust kinetic models for the LPMEOH{trademark} reaction system. The development was needed to meet the requirements for more accurate process simulations over a wide range of conditions. To this end, kinetic experiments were designed based on commercial needs and a D-Optimal design package. A database covering 53 different conditions was built. Two … more
Date: June 1, 2002
Creator: Peng, Xiang-Dong
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Production of Succinic Acid for Lignocellulosic Hydrolysates

Description: The purpose of this Cooperative Research and Development Agreement (CRADA) is to add and test new metabolic activities to existing microbial catalysts for the production of succinic acid from renewables. In particular, they seek to add to the existing organism the ability to utilize xylose efficiently and simultaneously with glucose in mixtures of sugars or to add succinic acid production to another strain and to test the value of this new capability for production of succinic acid from industr… more
Date: June 1, 2002
Creator: Davison, B.H. & Nghiem, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electrochemical and XRD characterization of platinum-ruthenium blacks for DMFC anodes.

Description: It is generally accepted that Pt-Ru alloy catalysts with an atomic Pt-to-Ru ratio of 1:1 generate the best anode perform'ance in the direct methanol fuel cell (DMFG). However, at near-ambient cell operating temperatures, Gasteiger et al. reported that a catalyst with significantly lower Ru content, {approx} 10 at %, offers the highest activity towards methanol. Recently, Dinh et al. demonstrated that the activity of different Pt-Ru catalysts with the same Pt-to-Ru atomic ratio in the bulk might… more
Date: January 1, 2002
Creator: Eickes, C. (Christian); Brosha, E. L. (Eric L.); Garzon, F. H. (Fernando H.); Purdy, G. M. (Geraldine M.); Zelenay, P. (Piotr); Morita, T. (Takanari) et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Porosimetric study of catalyst layer of polymer electrolyte fuel cell (PEFC)

Description: The cathode in a polymer electrolyte fuel cell (PEFC) contributes the largest energy loss due to the slow kinetics of the oxygen reduction reaction (ORR). This issue can be addressed by either developing new noble catalysts for the ORR or increasing catalyst utilization. One effective way to increase catalyst utilization is to increase the pore volume and porosity of the catalyst layer so that the catalyst clusters are maximally exposed to gas reactants. Here, we report our study on the porosim… more
Date: January 1, 2002
Creator: Xie, J. (Jian); Wilson, K. V. (Kennard V.) & Zawodzinski, T. A. (Thomas A.), Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Optimization of carbon-supported platinum cathode catalysts for DMFC operation.

Description: In this paper, we describe performance and optimization of carbon-supported cathode catalysts at low platinum loading. We find that at a loading below 0.6 mg cm-2 carbon-supported platinum outperforms platinum black as a DMFC cathode catalyst. A catalyst with a 1:1 volume ratio of the dry NafionTM to the electronically conducting phase (platinum plus carbon support) provides the best performance in oxygen reduction reaction. Thanks to improved catalyst utilization, carbon-supported catalysts wi… more
Date: January 1, 2002
Creator: Zhu, Y. (Yimin); Brosha, E. L. (Eric L.) & Zelenay, P. (Piotr)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Porosimetric study of catalyst layer of polymer electrolyte fuel cells.

Description: The porosimetry of the catalyst layer made by the 'decal process' was studied using mercury porosirnetry. The comparison of the porosimetric profiles between the carbon powder and the catalyst supported on carbon suggests that the loading of the catalyst onto the Vulcan XC-72 carbon changes the porosimetry of the catalyst/carbon. The porosimetry of the catalyst layer depends on the catalyst used and the Nafion content. Boiling the catalyst layer effectively increases the pore area and the poros… more
Date: January 1, 2002
Creator: Xie, J. (Jian); Wilson, K. V. (Kennard V.) & Zawodzinski, T. A. (Thomas A.), Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Transient control of carbon monoxide with staged PrOx reactors

Description: Fuel Processor systems generate hydrogen for fuel cell systems from hydrocarbon fuels such as gasoline for automotive fuel cell systems and natural gas for stationary fuel cell systems. These fuel processor systems must remove any contaminants to levels that won't poison the fuel cell before the outlet hydrogen-rich gas stream can be used by the fuel cell to generate electricity. Carbon monoxide is a contaminant that must be removed to levels of < 100 ppm or < 10 ppm depending on the CO t… more
Date: January 1, 2002
Creator: Inbody, M. A. (Michael A.); Borup, R. L. (Rodney L.) & Tafoya, J. (Jose I.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reformate fuel cell system durability

Description: The goal of this research is to identify the factors limiting the durability of fuel cells and fuel processors. This includes identifying PEM fuel cell durability issues for operating on pure hydrogen, and those that arise from the fuel processing of liquid hydrocarbons (e.g., gasoline) as a function of fuel composition and impurity content. Benchmark comparisons with the durability of fuel cells operating on pure hydrogen are used to identify limiting factors unique to fuel processing. We desc… more
Date: January 1, 2002
Creator: Borup, Rodney L.; Inbody, Michael A.; Uribe, Francisco A. & Tafoya, Jose I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fuels for fuel cells: Fuel and catalyst effects on carbon formation

Description: The goal of this research is to explore the effects of fuels, fuel constituents, additives and impurities on the performance of on-board hydrogen generation devices and consequently on the overall performance of fuel cell systems using reformed hydrocarbon fuels. Different fuels and components have been tested in automotive scale, adiabatic autothermal reactors to observe their relative reforming characteristics with various operating conditions. Carbon formation has been modeled and was experi… more
Date: January 1, 2002
Creator: Borup, R. L. (Rodney L.); Inbody, M. A. (Michael A.); Perry, W. L. (William Lee) & Parkinson, W. J. (William Jerry),
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling of Syngas Reactions and Hydrogen Generation Over Sulfides

Description: The objective of the research is to analyze pathways of reactions of hydrogen with oxides of carbon over sulfides, and to predict which characteristics of the sulfide catalyst (nature of metal, defect structure) give rise to the lowest barriers toward oxygenated hydrocarbon product. Reversal of these pathways entails the generation of hydrogen, which is also proposed for study. In this first year of study, adsorption reactions of H atoms and H{sub 2} molecules with MoS{sub 2}, both in molecular… more
Date: September 17, 2002
Creator: Klier, Kamil; Spirko, Jeffery A. & Neiman, Michael L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flow Characteristics of Pulse Cleaning System in Ceramic Filter

Description: The rigid ceramic filters have been recognized to be a most promising kind of equipment for the gas-solid separation and the cleaning of hot gases due to their unique properties and higher separation efficiency for larger than 5 {micro}m particles, which will well meet downstream system component protection and environmental standards. They have potential for increased efficiency in advanced coal-fired power generation systems like pressurized fluidized bed combustion (PFBC) and integrated gasi… more
Date: September 19, 2002
Creator: Zhongli, J.; Peng, S.; Chen, H. & Shi, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of Novel Electrocatalysts for Proton Exchange Membrane Fuel Cells Annual Report

Description: The Proton Exchange Membrane Fuel Cell (PEMFC) is one of the most promising power sources for stand-alone utility and electric vehicle applications. Platinum (Pt) Catalyst is used for both fuel and air electrodes in PEMFCs. However, carbon monoxide (CO) contamination of H{sub 2} greatly affects electro catalysts used at the anode of PEMFCs and decreases cell performance. The irreversible poisoning of the anode can occur even in CO concentrations as low as few parts per million (ppm). In this wo… more
Date: June 11, 2002
Creator: Ilias, Shamsuddin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Further studies on hydration of alkynes by the PtCl4-CO catalyst

Description: Under CO atmosphere, between 80 and 120 C, a glyme solution of PtCl{sub 4} forms a carbonyl compound that promotes hydration of internal as well as terminal alkynes to give aldehyde-free ketones. The catalytic process depends strongly on the electronic and steric nature of the substrates. Part of the carbonyl functions of the catalyst can be replaced by phosphine ligands. Chiral DIOP reacts with the PtCl{sub 4}-CO compound to give a catalyst that promotes partial kinetic resolution of a racemic… more
Date: January 18, 2002
Creator: Israelsohn, Osnat; Vollhardt, K. Peter C. & Blum, Jochanan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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MAGNETO-CHEMICAL CHARACTER STUDIES OF NOVEL Fe CATALYSTS FOR COAL LIQUEFACTION

Description: The objectives of the present study are: (1) To synthesize iron catalysts: Fe/MoO{sub 3}, and Fe/Co/MoO{sub 3} employing two distinct techniques: Pyrolysis with organic precursors and Co-precipitation of metal nitrates; (2) To investigate the magnetic character of the catalysts before and after exposure to CO and CO+H{sub 2} by (a) Mossbauer study of Iron (b) Zerofield Nuclear Magnetic Resonance study of Cobalt, and (c) Magnetic character of the catalyst composite; (3) To study the IR active su… more
Date: April 1, 2002
Creator: Akundi, Murty A.; Zhang, Jian H.; Murty, A.N. & Naidu, S.V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of N{sub 2}0 adsorption and decomposition on Fe-ZSM-5

Description: The interactions of N2O with H-ZSM-5 and Fe-ZSM-5 have been investigated using infrared spectroscopy and temperature-programmed reaction. Fe-ZSM-5 samples with Fe/Al ratios of 0.17 and 0.33 were prepared by solid-state exchange. It was determined that most of the iron in the samples of Fe-ZSM-5 is in the form of isolated cations, which have exchanged with Bronsted acid H+ in H-ZSM-5. The infrared spectrum of N2O adsorbed on H-ZSM-5 at 298 K exhibits bands at 2226 and 1308 cm-1 associated with v… more
Date: March 8, 2002
Creator: Wood, Benjamin R.; Reimer, Jeffrey A. & Bell, Alexis T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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LOW COST MULTI-LAYER FABRICATION METHOD FOR SOLID OXIDE FUEL CELLS

Description: Technology Management, Inc has evaluated the practical fabrication advantages and potential economic impact of a multi-pass screen printing process on the costs of fabricating planar solid oxide fuel cell stacks. During this program, multiple catalyzed binder systems were considered. Preliminary screening experiments resulted in four systems being selected for further evaluation. Inks were formulated using these binders in combination with at least three fuel cell materials (anode, cathode, and… more
Date: June 1, 2002
Creator: Milliken, Christopher; Ruhl, Robert & Hillman, Jennifer
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Redox Reactions of Metalloporphyrins and their Role in Catalyzed Reduction of Carbon Dioxide

Description: Pulse radiolysis and laser photolysis are used to study redox processes of metalloporphyrins and related complexes in order to evaluate these light absorbing molecules as sensitizers and intermediates in solar energy conversion schemes. The main thrust of the current studies is to investigate the role of reduced metalloporphyrins as intermediates in the catalyzed reduction of carbon dioxide. Studies involve cobalt and iron porphyrins, phthalocyanines, corroles, and corrins as homogeneous cataly… more
Date: September 1, 2002
Creator: Neta, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalysis of Reduction and Oxidation Reactions for Application in Gas Particle Filters

Description: The present study is a first part of an investigation addressing the simultaneous occurrence of oxidation and reduction reactions in catalytic filters. It has the objectives (a) to assess the state of knowledge regarding suitable (types of) catalysts for reduction and oxidation, (b) to collect and analyze published information about reaction rates of both NOx reduction and VOC oxidation, and (c) to adjust a lab-scale screening method to the requirements of an activity test with various oxidatio… more
Date: September 19, 2002
Creator: Udron, L. & Turek, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simultaneous Removal of Particulates and NOx Using Catalyst Impregnated Fibrous Ceramic Filters

Description: The research is focused on the development and commercialization of high efficiency, cost effective air pollution control system, which can replace in part air pollution control devices currently in use. In many industrial processes, hot exhaust gases are cooled down to recover heat and to remove air pollutants in exhaust gases. Conventional air pollution control devices such as bag filters, E.P. and adsorption towers withstand operating temperatures up to 300 C. Also, reheating is sometimes ne… more
Date: September 19, 2002
Creator: Choi, J. I.; Mun, S. H.; Kim, S. T.; Hong, M. S. & Lee, J. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synthesis of Mesoporous Aluminophosphates as Potential Catalysts in the Upgrading Petroleum Feedstocks

Description: This project focuses on the synthesis of mesoporous aluminophosphate (AlPO) catalysts for application in the acid catalyzed conversion of large petroleum feedstock compounds to Useful middle distillates and naphtha transportation fuels.
Date: March 20, 2002
Creator: Ingram, Conrad, PH.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Batch Microreactor Studies of Lignin Depolymerization by Bases. 1. Alcohol Solvents

Description: Biomass feedstocks contain roughly 10-30% lignin, a substance that can not be converted to fermentable sugars. Hence, most schemes for producing biofuels (ethanol) assume that the lignin coproduct will be utilized as boiler fuel to provide heat and power to the process. However, the chemical structure of lignin suggests that it will make an excellent high value fuel additive, if it can be broken down into smaller molecular units. From fiscal year 1997 through fiscal year 2001, Sandia National L… more
Date: May 1, 2002
Creator: MILLER, JAMES E.; EVANS, LINDSEY; LITTLEWOLF, ALICIA & TRUDELL, DANIEL E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hybrid Sulfur Recovery Process for Natural Gas Upgrading Quarterly Report

Description: This second quarter report of 2002 describes progress on a project funded by the U.S. Department of Energy (DOE) to test a hybrid sulfur recovery process for natural gas upgrading. The process concept represents a low cost option for direct treatment of natural gas streams to remove H{sub 2}S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day. This process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox a… more
Date: July 1, 2002
Creator: Srinivas, Girish; Gebhard, Steven C. & DeBerry, David W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dimensional effects in controlled structure supported catalysts derived from layered synthetic microstructures. Final progress report for period March 1, 1997 - February 28, 2000

Description: Several heterogeneous catalytic reactions show size dependence, whereby the specific rate changes with the average diameter of supported metal particles in the nanometer range. Geometric arguments relating the size dependence to the relative concentration of active sites on idealized crystal particles cannot account for all the observed results. In an effort to overcome the geometric limitations of supported particles, the authors had previously created novel supported metal catalysts called La… more
Date: September 13, 2002
Creator: Saltsburg, Howard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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