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Qin Qin - One of the best experts on this subject based on the ideXlab platform.
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thermodynamic study for hydrogen production from bio oil via sorption enhanced Steam Reforming comparison with conventional Steam Reforming
International Journal of Hydrogen Energy, 2017Co-Authors: Huaqing Xie, Yuanyuan Zhang, Jianrong Zhang, Qin QinAbstract:Abstract The thermodynamic analysis of the sorption-enhanced Steam Reforming (SESR) process of bio-oil for hydrogen production was investigated in terms of equilibrium compositions, energy consumption, with the comparison with the conventional Steam Reforming (CSR) process. Compared to CSR process, the SESR process could obtain higher H2 yield and concentration at lower temperature and S/C ratio, with both of the yield and concentration reaching over 90%. For decreasing the energy consumption, the sensible heat of the hot output streams from the two processes was recovered, with the recovered heat calculated by pinch analysis. To produce the same amount H2, the total energy demand of the SESR process was obviously lower the CSR process, especially under low temperature zone. Finally, the parameters of the two processes were optimized with a matrix analysis method. For SESR process, the optimal SR conditions were the temperature of 500 °C–600 °C, the S/C ratio of 3.0, under which the consumptions of bio-oil and energy were about 20% and about 30% lower than those under the optimal conditions of CSR process, respectively.
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hydrogen production via sorption enhanced catalytic Steam Reforming of bio oil
International Journal of Hydrogen Energy, 2016Co-Authors: Huaqing Xie, Zongliang Zuo, Zhicheng Han, Xin Yao, Qin QinAbstract:Abstract Hydrogen production via Steam Reforming of the bio-oil from corn cob by fast pyrolysis with in situ CO 2 sorption was investigated. The CaO obtained by calcining Ca(CH 3 COO) 2 ·H 2 O showed the best CO 2 adsorption efficiency among the three kinds of CaO from different precursors, and thus was selected as CO 2 sorbent used in the sorption-enhanced Steam Reforming process. For the bio-oil Steam Reforming, when the liquid hourly space velocity was lower than 0.15 h −1 , the yield and concentration of H 2 tended to the maximum. With the comparison to the case without CO 2 sorption, the yield and concentration of H 2 with CO 2 sorption were obviously improved with the carbon deposition effectively inhibited during the temperature range between 650 °C and 850 °C and the S/C range between 9 and 15. Through the sorption-enhanced Steam Reforming process, the highest hydrogen yield and concentration were obtained between 750 °C and 800 °C at S/C ratio of 12, and they were over 85% and 90%, respectively.
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hydrogen production via Steam Reforming of bio oil model compounds over supported nickel catalysts
Journal of Energy Chemistry, 2015Co-Authors: Huaqing Xie, Zongliang Zuo, Xin Yao, Wenjun Duan, Qin QinAbstract:Abstract The Steam Reforming of four bio-oil model compounds (acetic acid, ethanol, acetone and phenol) was investigated over Ni-based catalysts supported on Al 2 O 3 modified by Mg, Ce or Co in this paper. The activation process can improve the catalytic activity with the change of high-valence Ni (Ni 2 O 3 , NiO) to low-valence Ni (Ni, NiO). Among these catalysts after activation, the Ce-Ni/Co catalyst showed the best catalytic activity for the Steam Reforming of all the four model compounds. After long-term experiment at 700 °C and the S/C ratio of 9, the Ce-Ni/Co catalyst still maintained excellent stability for the Steam Reforming of the simulated bio-oil (mixed by the four compounds with the equal masses). With CaO calcinated from calcium acetate as CO 2 sorbent, the catalytic Steam Reforming experiment combined with continuous in situ CO 2 adsorption was performed. With the comparison of the case without the adding of CO 2 sorbent, the hydrogen concentration was dramatically improved from 74.8% to 92.3%, with the CO 2 concentration obviously decreased from 19.90% to 1.88%.
Huaqing Xie - One of the best experts on this subject based on the ideXlab platform.
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thermodynamic study for hydrogen production from bio oil via sorption enhanced Steam Reforming comparison with conventional Steam Reforming
International Journal of Hydrogen Energy, 2017Co-Authors: Huaqing Xie, Yuanyuan Zhang, Jianrong Zhang, Qin QinAbstract:Abstract The thermodynamic analysis of the sorption-enhanced Steam Reforming (SESR) process of bio-oil for hydrogen production was investigated in terms of equilibrium compositions, energy consumption, with the comparison with the conventional Steam Reforming (CSR) process. Compared to CSR process, the SESR process could obtain higher H2 yield and concentration at lower temperature and S/C ratio, with both of the yield and concentration reaching over 90%. For decreasing the energy consumption, the sensible heat of the hot output streams from the two processes was recovered, with the recovered heat calculated by pinch analysis. To produce the same amount H2, the total energy demand of the SESR process was obviously lower the CSR process, especially under low temperature zone. Finally, the parameters of the two processes were optimized with a matrix analysis method. For SESR process, the optimal SR conditions were the temperature of 500 °C–600 °C, the S/C ratio of 3.0, under which the consumptions of bio-oil and energy were about 20% and about 30% lower than those under the optimal conditions of CSR process, respectively.
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hydrogen production via sorption enhanced catalytic Steam Reforming of bio oil
International Journal of Hydrogen Energy, 2016Co-Authors: Huaqing Xie, Zongliang Zuo, Zhicheng Han, Xin Yao, Qin QinAbstract:Abstract Hydrogen production via Steam Reforming of the bio-oil from corn cob by fast pyrolysis with in situ CO 2 sorption was investigated. The CaO obtained by calcining Ca(CH 3 COO) 2 ·H 2 O showed the best CO 2 adsorption efficiency among the three kinds of CaO from different precursors, and thus was selected as CO 2 sorbent used in the sorption-enhanced Steam Reforming process. For the bio-oil Steam Reforming, when the liquid hourly space velocity was lower than 0.15 h −1 , the yield and concentration of H 2 tended to the maximum. With the comparison to the case without CO 2 sorption, the yield and concentration of H 2 with CO 2 sorption were obviously improved with the carbon deposition effectively inhibited during the temperature range between 650 °C and 850 °C and the S/C range between 9 and 15. Through the sorption-enhanced Steam Reforming process, the highest hydrogen yield and concentration were obtained between 750 °C and 800 °C at S/C ratio of 12, and they were over 85% and 90%, respectively.
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hydrogen production via Steam Reforming of bio oil model compounds over supported nickel catalysts
Journal of Energy Chemistry, 2015Co-Authors: Huaqing Xie, Zongliang Zuo, Xin Yao, Wenjun Duan, Qin QinAbstract:Abstract The Steam Reforming of four bio-oil model compounds (acetic acid, ethanol, acetone and phenol) was investigated over Ni-based catalysts supported on Al 2 O 3 modified by Mg, Ce or Co in this paper. The activation process can improve the catalytic activity with the change of high-valence Ni (Ni 2 O 3 , NiO) to low-valence Ni (Ni, NiO). Among these catalysts after activation, the Ce-Ni/Co catalyst showed the best catalytic activity for the Steam Reforming of all the four model compounds. After long-term experiment at 700 °C and the S/C ratio of 9, the Ce-Ni/Co catalyst still maintained excellent stability for the Steam Reforming of the simulated bio-oil (mixed by the four compounds with the equal masses). With CaO calcinated from calcium acetate as CO 2 sorbent, the catalytic Steam Reforming experiment combined with continuous in situ CO 2 adsorption was performed. With the comparison of the case without the adding of CO 2 sorbent, the hydrogen concentration was dramatically improved from 74.8% to 92.3%, with the CO 2 concentration obviously decreased from 19.90% to 1.88%.
Fabio B Noronha - One of the best experts on this subject based on the ideXlab platform.
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evaluation of the performance of ni la2o3 catalyst prepared from lanio3 perovskite type oxides for the production of hydrogen through Steam Reforming and oxidative Steam Reforming of ethanol
Applied Catalysis A-general, 2010Co-Authors: Sania M De Lima, Gary Jacobs, Burtron H Davis, Lisiane V Mattos, Adriana M Da Silva, Lidia O O Da Costa, Jose Mansur Assaf, Fabio B NoronhaAbstract:Abstract This paper studies the performance of LaNiO 3 perovskite-type oxide precursor as a catalyst for both Steam Reforming and oxidative Steam Reforming of ethanol. According to results of temperature-programmed desorption of adsorbed ethanol and by carrying out diffuse reflectance infrared Fourier transform spectroscopy analyses of ethanol Steam Reforming, ethanol decomposes to dehydrogenated species like acetaldehyde and acetyl, which at moderate temperatures, convert to acetate by the addition of hydroxyl groups. Demethanation of acetate occurs at higher temperatures, leading to a steady state coverage of carbonate. Catalyst deactivation occurs from the deposition of carbon on the surface of the catalyst. Both thermogravimetric and scanning electron microscopy analyses of postreaction samples indicate that lower reaction temperatures and lower H 2 O/EtOH ratios favor the deposition of filamentous carbon. However, less carbon formation occurs when the H 2 O/EtOH ratio is increased. Increasing reaction temperature or including O 2 in the feed suppresses filamentous carbon formation.
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study of catalyst deactivation and reaction mechanism of Steam Reforming partial oxidation and oxidative Steam Reforming of ethanol over co ceo2 catalyst
Journal of Catalysis, 2009Co-Authors: Sania M De Lima, Gary Jacobs, Burtron H Davis, Lisiane V Mattos, Adriana M Da Silva, Lidia O O Da Costa, Uschi M Graham, Fabio B NoronhaAbstract:The mechanisms of Co/ceria catalyst deactivation during Steam Reforming, oxidative Steam Reforming, and partial oxidation of ethanol were explored by comparing the results from different characterization techniques with those obtained from catalytic testing in a fixed-bed reactor. The nature of carbon deposition and the reaction conditions played critical roles in determining the extent of a catalyst deactivation. To shed light on the modes of carbon deposition under different reaction conditions, the mechanisms by which the adsorbed surface species turned over on the catalyst surface were evaluated using diffuse reflectance infrared spectroscopy under reaction conditions and temperature-programed desorption of adsorbed ethanol. In Steam Reforming, ethoxy species were converted to acetate and Steam promoted forward acetate demethanation. The resulting methane decomposed on Co metal particles. In this case, carbon diffused through the Co particle, nucleating growth sites for filamentous carbon behind it, with the resulting filaments lifting Co from the support. High H2O/ethanol ratios and oxygen promoted cleaning of the cobalt surface.
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Steam Reforming partial oxidation and oxidative Steam Reforming of ethanol over pt cezro2 catalyst
Journal of Catalysis, 2008Co-Authors: Sania M De Lima, Ivna O Da Cruz, Gary Jacobs, Burtron H Davis, Lisiane V Mattos, Fabio B NoronhaAbstract:Abstract The catalytic performance of a Pt/CeZrO 2 catalyst was tested for ethanol decomposition, Steam Reforming, partial oxidation, and oxidative Steam Reforming. At low temperature, the catalyst underwent significant deactivation during ethanol decomposition and Steam Reforming reactions. Co-feeding oxygen decreased the deactivation rate of the catalyst but adversely affected the selectivity to hydrogen. Increasing the reaction temperature greatly improved the stability of the catalyst. A reaction mechanism was proposed based on results obtained from in situ diffuse reflectance infrared spectroscopy analyses carried out under reaction conditions. Ethanol adsorbs as ethoxy species, which may follow one of two distinct pathways: (i) decomposition and production of CO, CH 4 , and H 2 or (ii) dehydrogenation to acetaldehyde and acetyl species. The dehydrogenated species may undergo oxidation to acetate species. The addition of water to the feed promoted the formation of acetate species. Water also facilitated the decomposition of acetaldehyde and acetate reactions, resulting in the formation of methane, CO, and carbonate.
Paul T Williams - One of the best experts on this subject based on the ideXlab platform.
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pyrolysis catalytic Steam Reforming of agricultural biomass wastes and biomass components for production of hydrogen syngas
Journal of The Energy Institute, 2019Co-Authors: Kaltume Akubo, Mohamad A Nahil, Paul T WilliamsAbstract:Abstract The pyrolysis-catalytic Steam Reforming of six agricultural biomass waste samples as well as the three main components of biomass was investigated in a two stage fixed bed reactor. Pyrolysis of the biomass took place in the first stage followed by catalytic Steam Reforming of the evolved pyrolysis gases in the second stage catalytic reactor. The waste biomass samples were, rice husk, coconut shell, sugarcane bagasse, palm kernel shell, cotton stalk and wheat straw and the biomass components were, cellulose, hemicellulose (xylan) and lignin. The catalyst used for Steam Reforming was a 10 wt.% nickel-based alumina catalyst (NiAl2O3). In addition, the thermal decomposition characteristics of the biomass wastes and biomass components were also determined using thermogravimetric analysis (TGA). The TGA results showed distinct peaks for the individual biomass components, which were also evident in the biomass waste samples reflecting the existence of the main biomass components in the biomass wastes. The results for the two-stage pyrolysis-catalytic Steam Reforming showed that introduction of Steam and catalyst into the pyrolysis-catalytic Steam Reforming process significantly increased gas yield and syngas production notably hydrogen. For instance, hydrogen composition increased from 6.62 to 25.35 mmol g−1 by introducing Steam and catalyst into the pyrolysis-catalytic Steam Reforming of palm kernel shell. Lignin produced the most hydrogen compared to cellulose and hemicellulose at 25.25 mmol g−1. The highest residual char production was observed with lignin which produced about 45 wt.% char, more than twice that of cellulose and hemicellulose.
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hydrogen production from high temperature pyrolysis Steam Reforming of waste biomass rice husk sugar cane bagasse and wheat straw
Energy & Fuels, 2013Co-Authors: Qari M K Waheed, Paul T WilliamsAbstract:Hydrogen production from pyrolysis, Steam Reforming, and catalytic Steam Reforming of sugar cane bagasse, wheat straw, and rice husk were investigated using a two stage pyrolysis-Reforming system. Biomass samples were pyrolyzed in the first stage, and the volatiles and liquids were reformed in the second stage in the presence of Steam. During all experiments, a high temperature of 950 °C was chosen for both the pyrolysis and Reforming stages. As compared to low temperatures, pyrolysis/Reforming carried out at higher temperature showed higher gas yields, particularly hydrogen gas yield. In addition, dolomite and 10 wt % Ni-dolomite were used to investigate the catalytic Steam Reforming of the biomass. In terms of hydrogen production, Steam Reforming using 10 wt % Ni-dolomite was the most effective, producing 25.44, 25.41, and 24.47 mmol of hydrogen per gram for rice husk, sugar cane bagasse, and wheat straw, respectively. The amount of deposited carbon on the reacted catalyst was from 1.31 wt % to 10.13 wt...
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Steam Reforming of crude glycerol with in situ co2 sorption
Bioresource Technology, 2010Co-Authors: Gavin L Rickett, Valerie Dupont, Paul T Williams, Yulong Ding, Haisheng Chen, Mojtaba GhadiriAbstract:Abstract Steam Reforming of the crude glycerol by-product of a biodiesel production plant has been evaluated experimentally at atmospheric pressure, with and without in situ CO2 sorption, in a continuous flow fixed-bed reactor between 400 °C and 700 °C. The process outputs were compared to those using pure glycerol. Thermodynamic equilibrium calculations were used to assess the effect on the Steam Reforming process of the main crude impurities (methanol and four fatty acid methyl esters). The crude glycerol and Steam conversions and the H2 purity reached 100%, 11% and 68%, respectively at 600 °C. No CH4 was found at and above 600 °C. Steam Reforming of crude glycerol with in situ CO2 removal is shown to be an effective means of achieving hydrogen purity above 88% in pre-CO2 breakthrough conditions.
L Garcia - One of the best experts on this subject based on the ideXlab platform.
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production of a hydrogen rich gas from fast pyrolysis bio oils comparison between homogeneous and catalytic Steam Reforming routes
International Journal of Hydrogen Energy, 2014Co-Authors: Javier Remon, Francois Broust, J Valette, Y Chhiti, I Alava, A R Fernandezakarregi, J Arauzo, L GarciaAbstract:Abstract The aim of the present work is to produce hydrogen from biomass through bio-oil. Two possible upgrading routes are compared: catalytic and non-catalytic Steam Reforming of bio-oils. The main originality of the paper is to cover all the steps involved in both routes: the fast pyrolysis step to produce the bio-oils, the water extraction for obtaining the bio-oil aqueous fractions and the final Steam Reforming of the liquids. Two reactors were used in the first pyrolysis step to produce bio-oils from the same wood feedstock: a fluidized bed and a spouted bed. The mass balances and the compositions of both batches of bio-oils and aqueous fractions were in good agreement between both processes. Carboxylic acids, alcohols, aldehydes, ketones, furans, sugars and aromatics were the main compounds detected and quantified. In the Steam Reforming experiments, catalytic and non-catalytic processes were tested and compared to produce a hydrogen-rich gas from the bio-oils and the aqueous fractions. Moreover, two different catalytic reactors were tested in the catalytic process (a fixed and a fluidized bed). Under the experimental conditions tested, the H 2 yields were as follows: catalytic Steam Reforming of the aqueous fractions in fixed bed (0.17 g H 2 /g organics) > non-catalytic Steam Reforming of the bio-oils (0.14 g H 2 /g organics) > non-catalytic Steam Reforming of the aqueous fractions (0.13 g H 2 /g organics) > catalytic Steam Reforming of the aqueous fractions in fluidized bed (0.07 g H 2 /g organics). These different H 2 yields are a consequence of the different temperatures used in the Reforming processes (650 °C and 1400 °C for the catalytic and the non-catalytic, respectively) as well as the high spatial velocity employed in the catalytic tests, which was not sufficiently low to reach equilibrium in the fluidized bed reactor.
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ni al coprecipitated catalysts modified with magnesium and copper for the catalytic Steam Reforming of model compounds from biomass pyrolysis liquids
Applied Catalysis B-environmental, 2012Co-Authors: F Bimbela, L Garcia, De Chen, J Ruiz, J ArauzoAbstract:Abstract Ni/Al coprecipitated catalysts modified with magnesium and copper have been prepared by a constant pH technique and tested in the catalytic Steam Reforming of model compounds (acetic acid, acetol and butanol) from biomass pyrolysis liquids at 650 °C and atmospheric pressure. Catalysts with different copper contents, reduced at 650 °C for 1 h, were tested in the Steam Reforming of acetic acid with a Steam/carbon (S/C) molar ratio of 5.6. The best performance and the highest hydrogen yield in these conditions were achieved with the 5% Cu catalyst. This catalyst reduced at 650 °C during 10 h showed a high activity, close to the thermodynamic equilibrium, and a stable performance during 12 h in the Steam Reforming of acetic acid with a S/C = 5.6, using a short space time of 1.00 g catalyst min/g acetic acid. Copper as a promoter produces counterbalanced effects: a decrease in the initial Reforming activity and an enhancement of the catalyst stability. The initial Steam Reforming activity decreased and the CH 4 yield increased concurrently with increasing the copper content, because of the Ni dilution effect. Copper has a positive effect inhibiting the formation of encapsulating coke, identified as the cause for deactivation in acetic acid Steam Reforming with a Steam-to-carbon molar ratio (S/C) of 5.6. However, such a positive effect of copper has not been observed in acetic acid Steam Reforming with S/C = 14.7 or in the Steam Reforming of acetol and butanol.
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catalytic Steam Reforming of model compounds of biomass pyrolysis liquids in fluidized bed reactor with modified ni al catalysts
Journal of Analytical and Applied Pyrolysis, 2009Co-Authors: J A Medrano, L Garcia, M Oliva, J Ruiz, J ArauzoAbstract:Abstract Catalytic Steam Reforming of acetic acid and hydroxyacetone (acetol) as model compounds of the aqueous fraction of bio-oil (biomass derived pyrolysis liquids) was studied in fluidized bed reactor over Ni/Al catalysts modified with calcium or magnesium. Attrition tests showed that the use of small quantities of these promoters improved the mechanical strength of the Reforming catalyst. An optimum Ca/Al molar ratio of 0.12 and a Mg/Al molar ratio of 0.26 leaded to attrition rates of 0.22 and 0.27 wt%/h, respectively. Steam Reforming experiments were performed at 650 °C and a Steam to carbon molar ratio (S/C) of 5.58. The promoted catalysts showed different acetic acid Steam Reforming activities depending on the Ca/Al or Mg/Al molar ratios. Magnesium modified catalysts with a Mg/Al molar ratios of 0.26 and 0.50 showed good performances with almost no activity loss with time in contrast to the calcium modified catalysts that showed higher CO and CH4 yields. The addition of calcium generated a NiO phase with less interaction with the support. The highest H2 yield and carbon conversion in acetic Steam Reforming were obtained by a magnesium promoted catalyst with a Mg/Al ratio of 0.26, while the nonpromoted Ni/Al catalyst showed the best performance in acetol Steam Reforming. Then, the nature of the organic compound influenced the performance of the different catalysts.
