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Full-Text Articles in Chemical Engineering

Catalytic Fast Pyrolysis Of Wood And Alcohol Mixtures In A Fluidized Bed Reactor, George W. Huber, H. Zhang, T. R. Carlson, R. Xiao Jan 2012

Catalytic Fast Pyrolysis Of Wood And Alcohol Mixtures In A Fluidized Bed Reactor, George W. Huber, H. Zhang, T. R. Carlson, R. Xiao

George W. Huber

Catalytic fast pyrolysis (CFP) of pine wood, alcohols (methanol, 1-propanol, 1-butanol and 2-butanol) and their mixtures with ZSM-5 catalyst were conducted in a bubbling fluidized bed reactor. The effects of temperature and weight hourly space velocity (WHSV) on the product carbon yields and selectivities of CFP of pure pine wood and methanol were investigated. A maximum carbon yield of petrochemicals (aromatics + C2–C4 olefins + C5 compounds) from pine wood of 23.7% was obtained at a temperature of 600 °C and WHSV of 0.35 h−1. A maximum petrochemical yield from methanol of 80.7% was obtained at a temperature of 400 …


Production Of Renewable Aromatic Compounds By Catalytic Fast Pyrolysis Of Lignocellulosic Biomass With Bifunctional Ga/Zsm-5 Catalysts, George W. Huber, Y. Cheng, J. Jae, J. Shi, W. Fan Jan 2012

Production Of Renewable Aromatic Compounds By Catalytic Fast Pyrolysis Of Lignocellulosic Biomass With Bifunctional Ga/Zsm-5 Catalysts, George W. Huber, Y. Cheng, J. Jae, J. Shi, W. Fan

George W. Huber

Heiße Sache! Mit dem neuen difunktionellen Katalysator Ga/ZSM-5 entstehen aromatische Verbindungen bei der schnellen katalytischen Pyrolyse von Biomasse selektiver. Der ZSM-5-Katalysator mit Ga-Promotor wandelt Olefine wie Ethen und Propen, die als Intermediate entstehen, effizienter in Arene (insbesondere Benzol) um. Ga/ZSM-5 vermittelt auch Decarbonylierungen und die Aromatisierung von Olefinen.


Kinetics And Reaction Chemistryifor Slow Pyrolysis Of Enzymatic Hydrolysis Lignin And Organosolv Extracted Lignin Derived From Maplewood, George W. Huber, J. Cho, S. Chu, P. J. Dauenhaue Jan 2012

Kinetics And Reaction Chemistryifor Slow Pyrolysis Of Enzymatic Hydrolysis Lignin And Organosolv Extracted Lignin Derived From Maplewood, George W. Huber, J. Cho, S. Chu, P. J. Dauenhaue

George W. Huber

The kinetics and reaction chemistry for the pyrolysis of Maplewood lignin were investigated using both a pyroprobe reactor and a thermogravimetric analyser mass spectrometry (TGA-MS). Lignin residue after enzymatic hydrolysis and organosolv lignin derived from Maplewood were used to measure the kinetic behaviours of lignin pyrolysis and to analyse pyrolysis product distributions. The enzymatic lignin residue pyrolyzed at lower temperature than that of organosolv lignin. The differential thermogravimetric (DTG) peaks for pyrolysis of the enzymatic residue were more similar to the DTG peaks for pyrolysis of the original Maplewood than DTG of the organosolv lignin. The condensable liquid volatile products …


Identification And Thermochemical Analysis Of High-Lignin Feedstocks For Biofuel And Biochemical Production, Venugopal Mendu, Anne E. Harman-Ware, Mark Crocker, Jungho Jae, Jozsef Stork, Samuel Morton, Andrew Placido, George W. Huber, Seth Debolt Oct 2011

Identification And Thermochemical Analysis Of High-Lignin Feedstocks For Biofuel And Biochemical Production, Venugopal Mendu, Anne E. Harman-Ware, Mark Crocker, Jungho Jae, Jozsef Stork, Samuel Morton, Andrew Placido, George W. Huber, Seth Debolt

George W. Huber

Background - Lignin is a highly abundant biopolymer synthesized by plants as a complex component of plant secondary cell walls. Efforts to utilize lignin-based bioproducts are needed. Results - Herein we identify and characterize the composition and pyrolytic deconstruction characteristics of high-lignin feedstocks. Feedstocks displaying the highest levels of lignin were identified as drupe endocarp biomass arising as agricultural waste from horticultural crops. By performing pyrolysis coupled to gas chromatography-mass spectrometry, we characterized lignin-derived deconstruction products from endocarp biomass and compared these with switchgrass. By comparing individual pyrolytic products, we document higher amounts of acetic acid, 1-hydroxy-2-propanone, acetone and furfural …


A Systematic Method To Evaluate And Develop Renewable Energy Technologies, George W. Huber, A. A. Upadhye, W. Qi Sep 2011

A Systematic Method To Evaluate And Develop Renewable Energy Technologies, George W. Huber, A. A. Upadhye, W. Qi

George W. Huber

No abstract provided.


Chemistry Of Furan Conversion Into Aromatics And Olefins Over Hzsm-5: A Model Biomass Conversion Reaction, George W. Huber, Y. Cheng Jan 2011

Chemistry Of Furan Conversion Into Aromatics And Olefins Over Hzsm-5: A Model Biomass Conversion Reaction, George W. Huber, Y. Cheng

George W. Huber

The conversion of furan (a model of cellulosic biomass) over HZSM-5 was investigated in a thermogravimetric analysis–mass spectrometry system, in situ Fourier transform infrared analysis, and in a continuous-flow fixed-bed reactor. Furan adsorbed as oligomers at room temperature with a 1.73 of adsorbed furan/Al ratio. These oligomers were polycyclic aromatic compounds that were converted to CO, CO2, aromatics, and olefins at temperatures from 400 to 600 °C. Aromatics (e.g., benzene, toluene, and naphthalene), oligomer isomers (e.g., benzofuran, 2,2-methylenebisfuran, and benzodioxane), and heavy oxygenates (C12+ oligomers) were identified as intermediates formed inside HZSM-5 at different reaction temperatures. During furan conversion, graphite-type …


Catalytic Conversion Of Biomass-Derived Feedstocks Into Olefins And Aromatics With Zsm-5: The Hydrogen To Carbon Effective Ratio, George W. Huber, H. Zhang, Y. Cheng, T. P. Vispute, R. Xiao Jan 2011

Catalytic Conversion Of Biomass-Derived Feedstocks Into Olefins And Aromatics With Zsm-5: The Hydrogen To Carbon Effective Ratio, George W. Huber, H. Zhang, Y. Cheng, T. P. Vispute, R. Xiao

George W. Huber

Catalytic conversion of ten biomass-derived feedstocks, i.e. glucose, sorbitol, glycerol, tetrahydrofuran, methanol and different hydrogenated bio-oil fractions, with different hydrogen to carbon effective (H/Ceff) ratios was conducted in a gas-phase flow fixed-bed reactor with a ZSM-5 catalyst. The aromatic + olefin yield increases and the coke yield decreases with increasing H/Ceff ratio of the feed. There is an inflection point at a H/Ceff ratio = 1.2, where the aromatic + olefin yield does not increase as rapidly as it does prior to this point. The ratio of olefins to aromatics also increases with increasing H/Ceff ratio. CO and CO2 yields …


Simulating Infrared Spectra And Hydrogen Bonding In Cellulose Iβ At Elevated Temperatures, George W. Huber, V. Agarwal, W. C. Conner Jr. Jan 2011

Simulating Infrared Spectra And Hydrogen Bonding In Cellulose Iβ At Elevated Temperatures, George W. Huber, V. Agarwal, W. C. Conner Jr.

George W. Huber

We have modeled the transformation of cellulose Iβ to a high temperature (550 K) structure, which is considered to be the first step in cellulose pyrolysis. We have performed molecular dynamics simulations at constant pressure using the GROMOS 45a4 united atom forcefield. To test the forcefield, we computed the density, thermal expansion coefficient, total dipole moment, and dielectric constant of cellulose Iβ, finding broad agreement with experimental results. We computed infrared (IR) spectra of cellulose Iβ over the range 300–550 K as a probe of hydrogen bonding. Computed IR spectra were found to agree semi-quantitatively with experiment, especially in the …


Production Of Green Aromatics And Olefins By Catalytic Fast Pyrolysis Of Wood Sawdust, George W. Huber, T. R. Carlson, Y. -T Cheng, J Jae Jan 2011

Production Of Green Aromatics And Olefins By Catalytic Fast Pyrolysis Of Wood Sawdust, George W. Huber, T. R. Carlson, Y. -T Cheng, J Jae

George W. Huber

Catalytic fast pyrolysis of pine wood sawdust and furan (a model biomass compound) with ZSM-5 based catalysts was studied with three different reactors: a bench scale bubbling fluidized bed reactor, a fixed bed reactor and a semi-batch pyroprobe reactor. The highest aromatic yield from sawdust of 14% carbon in the fluidized bed reactor was obtained at low biomass weight hourly space velocities (less than 0.5 h−1) and high temperature (600 °C). Olefins (primarily ethylene and propylene) were also produced with a carbon yield of 5.4% carbon. The biomass weight hourly space velocity and the reactor temperature can be used to …


Production Of Furfural And Carboxylic Acids From Waste Aqueous Hemicellulose Solutions From The Pulp And Paper And Cellulosic Ethanol Industries, George W. Huber, R. Xing, W. Qi Jan 2011

Production Of Furfural And Carboxylic Acids From Waste Aqueous Hemicellulose Solutions From The Pulp And Paper And Cellulosic Ethanol Industries, George W. Huber, R. Xing, W. Qi

George W. Huber

In this paper we present a new process to produce furfural and co-products of formic and acetic acids from waste aqueous hemicellulose solutions using a continuous two zone biphasic reactor. We estimate this approach uses 67% to 80% less energy than the current industrial processes to produce furfural. An economic analysis indicates that furfural can be produced with this process at 366 US$ per metric ton which is 25% of the selling price of furfural in the U.S. market today. This analysis assumes a plant capacity of 78 kiloton per year of furfural, 12 kiloton per year of formic acid …


Renewable Gasoline From Aqueous Phase Hydrodeoxygenation Of Aqueous Sugar Solutions Prepared By Hydrolysis Of Maple Wood, George W. Huber, N. Li, G. A. Tompsett, T. Zhang, J. Shi, C. E. Wyman Jan 2011

Renewable Gasoline From Aqueous Phase Hydrodeoxygenation Of Aqueous Sugar Solutions Prepared By Hydrolysis Of Maple Wood, George W. Huber, N. Li, G. A. Tompsett, T. Zhang, J. Shi, C. E. Wyman

George W. Huber

In this paper we demonstrate an integrated process for the production of high octane gasoline from maple wood by hydrolysis of maple wood into aqueous carbohydrate solutions followed by aqueous phase hydrodeoxygenation of the sugar solutions. The aqueous carbohydrate solutions were prepared by both hydrolysis in hot water and hydrolysis with dilute acids (H2SO4, oxalic acid). The aqueous carbohydrate solutions were a mixture of xylose, water soluble hemicellulose oligomers, acetic acid, glucose, glucose oligomers, and probably some lignin polymers. Hydrolysis with hot water produced primarily hemicellulose oligomers whereas hydrolysis with acids produced mainly xylose and acetic acid. The hydrolysis co-product …


Kinetics Of Furfural Production By Dehydration Of Xylose In A Biphasic Reactor With Microwave Heating, George W. Huber, R. Weingarten, J. Cho, W. C. Conner Jr. Jan 2010

Kinetics Of Furfural Production By Dehydration Of Xylose In A Biphasic Reactor With Microwave Heating, George W. Huber, R. Weingarten, J. Cho, W. C. Conner Jr.

George W. Huber

In this paper we report a kinetic model for the dehydration of xylose to furfural in a biphasic batch reactor with microwave heating. There are four key steps in our kinetic model: (1) xylose dehydration to form furfural; (2) furfural reaction to form degradation products; (3) furfural reaction with xylose to form degradation products, and (4) mass transfer of furfural from the aqueous phase into the organic phase (methyl isobutyl ketone - MIBK). This kinetic model was used to fit experimental data collected in this study. The apparent activation energy for xylose dehydration is higher than the apparent activation energy …


Production Of Jet And Diesel Fuel Range Alkanes From Waste Hemicellulose-Derived Aqueous Solutions, George W. Huber, R. Xing, A. V. Subrahmanyam, H. Olcay, W. Qi, G. P. Van Walsum, H. P. Pendse Dec 2009

Production Of Jet And Diesel Fuel Range Alkanes From Waste Hemicellulose-Derived Aqueous Solutions, George W. Huber, R. Xing, A. V. Subrahmanyam, H. Olcay, W. Qi, G. P. Van Walsum, H. P. Pendse

George W. Huber

In this paper we report a novel four-step process for the production of jet and diesel fuel range alkanes from hemicellulose extracts derived from northeastern hardwood trees. The extract is representative of a byproduct that could be produced by wood-processing industries such as biomass boilers or pulp mills in the northeastern U.S. The hemicellulose extract tested in this study contained mainly xylose oligomers (21.2 g/l xylose after the acid hydrolysis) as well as 0.31 g/l glucose, 0.91 g/l arabinose, 0.2 g/l lactic acid, 2.39 g/l acetic acid, 0.31 g/l formic acid, and other minor products. The first step in this …


Kinetics And Mechanism Of Cellulose Pyrolysis, George W. Huber, Y. C. Lin, J Cho, P. R. Westmoreland Jan 2009

Kinetics And Mechanism Of Cellulose Pyrolysis, George W. Huber, Y. C. Lin, J Cho, P. R. Westmoreland

George W. Huber

In this paper we report the kinetics and chemistry of cellulose pyrolysis using both a Pyroprobe reactor and a thermogravimetric analyzer mass spectrometer (TGA-MS). We have identified more than 90% of the products from cellulose pyrolysis in a Pyroprobe reactor with a liquid nitrogen trap. The first step in the cellulose pyrolysis is the depolymerization of solid cellulose to form levoglucosan (LGA; 6,8-dioxabicyclo[3.2.1]octane-2,3,4-triol). LGA can undergo dehydration and isomerization reactions to form other anhydrosugars including levoglucosenone (LGO; 6,8-dioxabicyclo[3.2.1]oct-2-en-4-one), 1,4:3,6-dianhydro-β-d-glucopyranose (DGP) and 1,6-anhydro-β-d-glucofuranose (AGF; 2,8-dioxabicyclo[3.2.1]octane-4,6,7-triol). The anhydrosugars can react further to form furans, such as furfural (furan-2-carbaldehyde) and hydroxymethylfurfural (HMF; 5-(hydroxymethyl)furan-2-carbaldehyde) …


Aromatic Production From Catalytic Fast Pyrolysis Of Biomass-Derived Feedstocks, George W. Huber, T. R. Carlson, G. A. Tompsett Jan 2009

Aromatic Production From Catalytic Fast Pyrolysis Of Biomass-Derived Feedstocks, George W. Huber, T. R. Carlson, G. A. Tompsett

George W. Huber

The conversion of biomass compounds to aromatics by thermal decomposition in the presence of catalysts was investigated using a pyroprobe analytical pyrolyzer. The first step in this process is the thermal decomposition of the biomass to smaller oxygenates that then enter the catalysts pores where they are converted to CO, CO2, water, coke and volatile aromatics. The desired reaction is the conversion of biomass into aromatics, CO2 and water with the undesired products being coke and water. Both the reaction conditions and catalyst properties are critical in maximizing the desired product selectivity. High heating rates and high catalyst to feed …


The Critical Role Of Heterogeneous Catalysis In Lignocellulosic Biomass Conversion, George W. Huber, Y. -C Lin Jan 2009

The Critical Role Of Heterogeneous Catalysis In Lignocellulosic Biomass Conversion, George W. Huber, Y. -C Lin

George W. Huber

Lignocellulosic biofuels have a tremendous potential to reduce problems caused by our dependence on fossil fuels. The current roadblock with biofuels is the lack of economical conversion technologies. Heterogeneous catalysis offers immense potential in helping to make lignocellulosic biofuels a commercial reality. In this article we discuss the central role of heterogeneous catalysis in biomass conversion. We review the science of catalysis and the different routes to make biofuels. During the last several decades multiple new spectroscopic, theoretical, and synthesis tools are available that allow us to study catalysis at a molecular level. These new tools will allow us to …


Production Of Hydrogen, Alkanes And Polyols By Aqueous Phase Processing Of Wood-Derived Pyrolysis Oils, George W. Huber, T. P. Vispute Jan 2009

Production Of Hydrogen, Alkanes And Polyols By Aqueous Phase Processing Of Wood-Derived Pyrolysis Oils, George W. Huber, T. P. Vispute

George W. Huber

Pyrolysis oils are the cheapest liquid fuel derived from lignocellulosic biomass. However, pyrolysis oils are a very poor quality liquid fuel that cannot be used in conventional diesel and internal combustion engines. In this paper we show that hydrogen, alkanes (ranging from C1 to C6) and polyols (ethylene glycol, 1,2-propanediol, 1,4-butanediol) can be produced from the aqueous fraction of wood-derived pyrolysis oils (bio-oils). The pyrolysis oil was first phase separated into aqueous and non-aqueous fraction by addition of water. The aqueous phase of bio-oil contained sugars; anhydrosugars; acetic acid; hydroxyacetone; furfural and small amounts of guaiacols. The aqueous fraction was …


Green Gasoline By Catalytic Fast Pyrolysis Of Solid Biomass Derived Compounds, George W. Huber, A. Corma, L. Sauvanaud, P. O'Conner Jan 2008

Green Gasoline By Catalytic Fast Pyrolysis Of Solid Biomass Derived Compounds, George W. Huber, A. Corma, L. Sauvanaud, P. O'Conner

George W. Huber

A fuelling success: High-quality aromatic fuel additives can be produced directly from solid biomass feedstocks by catalytic fast pyrolysis in a single catalytic reactor at short residence times. High heating rates and catalyst-to-feed ratios are needed to ensure that pyrolized biomass compounds enter the pores of the ZSM5 catalyst and that thermal decomposition is avoided. Product selectivity is a function of the active site and pore structure of the catalyst.


Synergies Between Bio- And Oil Refineries For The Production Of Fuels From Biomass, George W. Huber, A. Corma Jan 2007

Synergies Between Bio- And Oil Refineries For The Production Of Fuels From Biomass, George W. Huber, A. Corma

George W. Huber

As petroleum prices continue to increase, it is likely that biofuels will play an ever-increasing role in our energy future. The processing of biomass-derived feedstocks (including cellulosic, starch- and sugar-derived biomass, and vegetable fats) by catalytic cracking and hydrotreating is a promising alternative for the future to produce biofuels, and the existing infrastructure of petroleum refineries is well-suited for the production of biofuels, allowing us to rapidly transition to a more sustainable economy without large capital investments for new reaction equipment. This Review discusses the chemistry, catalysts, and challenges involved in the production of biofuels.


Liquid-Phase Catalytic Processing Of Biomass-Derived Oxygenated Hydrocarbons To Fuels And Chemicals, George W. Huber, J. Chheda, J. A. Dumesic Jan 2007

Liquid-Phase Catalytic Processing Of Biomass-Derived Oxygenated Hydrocarbons To Fuels And Chemicals, George W. Huber, J. Chheda, J. A. Dumesic

George W. Huber

Biomass has the potential to serve as a sustainable source of energy and organic carbon for our industrialized society. The focus of this Review is to present an overview of chemical catalytic transformations of biomass-derived oxygenated feedstocks (primarily sugars and sugar-alcohols) in the liquid phase to value-added chemicals and fuels, with specific examples emphasizing the development of catalytic processes based on an understanding of the fundamental reaction chemistry. The key reactions involved in the processing of biomass are hydrolysis, dehydration, isomerization, aldol condensation, reforming, hydrogenation, and oxidation. Further, it is discussed how ideas based on fundamental chemical and catalytic concepts …


Synthesis Of Transportation Fuels From Biomass:  Chemistry, Catalysts, And Engineering, George W. Huber, S. Iborra, A. Corma Jan 2006

Synthesis Of Transportation Fuels From Biomass:  Chemistry, Catalysts, And Engineering, George W. Huber, S. Iborra, A. Corma

George W. Huber

No abstract provided.


Experimental And Dft Studies Of The Conversion Of Ethanol And Acetic Acid On Ptsn-Based Catalysts, George W. Huber, R. Acal, J. W. Shabaker, M. A. Sanchez-Castillo, J. A. Dumesic Jan 2005

Experimental And Dft Studies Of The Conversion Of Ethanol And Acetic Acid On Ptsn-Based Catalysts, George W. Huber, R. Acal, J. W. Shabaker, M. A. Sanchez-Castillo, J. A. Dumesic

George W. Huber

Reaction kinetics studies were conducted for the conversions of ethanol and acetic acid over silica-supported Pt and Pt/Sn catalysts at temperatures from 500 to 600 K. Addition of Sn to Pt catalysts inhibits the decomposition of ethanol to CO, CH4, and C2H6, such that PtSn-based catalysts are active for dehydrogenation of ethanol to acetaldehyde. Furthermore, PtSn-based catalysts are selective for the conversion of acetic acid to ethanol, acetaldehyde, and ethyl acetate, whereas Pt catalysts lead mainly to decomposition products such as CH4 and CO. These results are interpreted using density functional theory (DFT) calculations for various adsorbed species and transition …


Production Of Liquid Alkanes By Aqueous-Phase Processing Of Biomass-Derived Carbohydrates, George W. Huber, J. Chheda, C. B. Barrett, J. A. Dumesic Dec 2004

Production Of Liquid Alkanes By Aqueous-Phase Processing Of Biomass-Derived Carbohydrates, George W. Huber, J. Chheda, C. B. Barrett, J. A. Dumesic

George W. Huber

Liquid alkanes with the number of carbon atoms ranging from C7 to C15 were selectively produced from biomass-derived carbohydrates by acid-catalyzed dehydration, which was followed by aldol condensation over solid base catalysts to form large organic compounds. These molecules were then converted into alkanes by dehydration/hydrogenation over bifunctional catalysts that contained acid and metal sites in a four-phase reactor, in which the aqueous organic reactant becomes more hydrophobic and a hexadecane alkane stream removes hydrophobic species from the catalyst before they go on further to form coke. These liquid alkanes are of the appropriate molecular weight to be used as …


Renewable Alkanes By Aqueous-Phase Reforming Of Biomass-Derived Oxygenates, George W. Huber, R. D. Cortright, J. A. Dumesic Jan 2004

Renewable Alkanes By Aqueous-Phase Reforming Of Biomass-Derived Oxygenates, George W. Huber, R. D. Cortright, J. A. Dumesic

George W. Huber

A clean stream of alkanes from renewable biomass resources is obtained through aqueous-phase reforming in a single reactor. Alkanes are produced from biomass-derived sorbitol through a bifunctional pathway (see scheme) that involves the dehydration of sorbitol on acid sites (SiO2/Al2O3) and hydrogenation of intermediates on a metal catalyst under a H2 atmosphere. Hydrogen is produced from sorbitol and water on the metal catalyst in the same reactor.


Effect Of Sn On The Reactivity Of Cu Surfaces, George W. Huber, A. Gokale, J. A. Dumesic, M. Mavrikakis Jan 2004

Effect Of Sn On The Reactivity Of Cu Surfaces, George W. Huber, A. Gokale, J. A. Dumesic, M. Mavrikakis

George W. Huber

Periodic, density functional theory (DFT-GGA) calculations, using PW91 (self-consistently) and RPBE functionals, have been employed to determine preferred binding sites, adsorbate structures, and binding energies for the adsorption of atomic (H, N, O, S, and C), molecular (NO and CO), and radical (OH) species on Cu(111) and CuSn(0001) alloy surfaces. Our results indicate the following order in the binding energies from the least to the most strongly bound:  NO < CO < H < OH < N < O < S < C for Cu-terminated CuSn(0001). On Cu(111), the corresponding relative order of adsorbates from the least strongly bound to the most strongly bound is CO < NO < H < OH < N < O < S < C. On the Sn-terminated CuSn(0001) surface, CO does not adsorb and the relative order of adsorbates from the least strongly bound to the most strongly bound is NO < H < OH < N < S < O < C. For all adsorbates, the binding on Cu-terminated CuSn(0001) is stronger than on Cu(111), resulting from a combination of electronic and strain effects caused by the addition of Sn to Cu. CO dissociation is endothermic on Cu-terminated CuSn(0001) and Cu(111) surfaces, while CO oxidation is exothermic on these surfaces. OH dissociation is endothermic on all three surfaces. On all surfaces studied, thermodynamics of NO decomposition are much more favorable than those of CO and OH dissociation on the corresponding surfaces. Our microcalorimetric studies of the interaction of NO with Cu/SiO2 and Cu6Sn5/SiO2 samples give initial heats of 270 (2.80 eV) and 130 (1.35 eV) kJ/mol, respectively. These values correspond to the decomposition of NO to give adsorbed oxygen plus gaseous N2 on Cu/SiO2 and adsorbed oxygen plus gaseous N2O on the Sn-terminated phase of Cu6Sn5/SiO2.


Raney Ni-Sn Catalyst For H2 Production From Biomass-Derived Hydrocarbons, George W. Huber, J. W. Shabaker, J. A. Dumesic Jan 2003

Raney Ni-Sn Catalyst For H2 Production From Biomass-Derived Hydrocarbons, George W. Huber, J. W. Shabaker, J. A. Dumesic

George W. Huber

Hydrogen (H2) was produced by aqueous-phase reforming of biomass-derived oxygenated hydrocarbons at temperatures near 500 kelvin over a tin-promoted Raney-nickel catalyst. The performance of this non–precious metal catalyst compares favorably with that of platinum-based catalysts for production of hydrogen from ethylene glycol, glycerol, and sorbitol. The addition of tin to nickel decreases the rate of methane formation from C-O bond cleavage while maintaining the high rates of C-C bond cleavage required for hydrogen formation.


Aqueous-Phase Reforming Of Ethylene Glycol Over Supported Platinum Catalysts, George W. Huber, J W. Shabaker, R. R. Davda, R. D. Cortright, J. A. Dumesic Jan 2003

Aqueous-Phase Reforming Of Ethylene Glycol Over Supported Platinum Catalysts, George W. Huber, J W. Shabaker, R. R. Davda, R. D. Cortright, J. A. Dumesic

George W. Huber

Aqueous-phase reforming of 10 wt% ethylene glycol solutions was studied at temperatures of 483 and 498 K over Pt-black and Pt supported on TiO2, Al2O3, carbon, SiO2, SiO2-Al2O3, ZrO2, CeO2, and ZnO. High activity for the production of H2 by aqueous-phase reforming was observed over Pt-black and over Pt supported on TiO2, carbon, and Al2O3 (i.e., turnover frequencies near 8-15 min-1 at 498 K); moderate catalytic activity for the production of hydrogen is demonstrated by Pt supported on SiO2-Al2O3 and ZrO2 (turnover frequencies near 5 min-1); and lower catalytic activity is exhibited by Pt supported on CeO2, ZnO, and SiO2 …


Gd Promotion Of Co/Sio2 Fischer–Tropsch Synthesis Catalysts, George W. Huber, S. J.M Butala, M. L. Lee, C. H. Bartholomew Jan 2001

Gd Promotion Of Co/Sio2 Fischer–Tropsch Synthesis Catalysts, George W. Huber, S. J.M Butala, M. L. Lee, C. H. Bartholomew

George W. Huber

Addition of Gd to Co/SiO2 Fischer–Tropsch synthesis catalysts (1) increases reducibility to Co metal, (2) decreases CH4 selectivity, (3) increases activity for CO hydrogenation based on the mass of Co, and (4) causes carbon deposition at lower temperatures when compared to the unpromoted catalyst. The intrinsic activity, based on H2 chemisorption surface area, is the same for both unpromoted and promoted catalysts.