The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Binlin Dou - One of the best experts on this subject based on the ideXlab platform.
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Hydrogen production by sorption-enhanced chemical looping steam reforming of ethanol in an alternating Fixed-Bed Reactor: Sorbent to catalyst ratio dependencies
Energy Conversion and Management, 2018Co-Authors: Binlin Dou, Kaiqiang Wang, Zilong Wang, Guomin Cui, Haisheng Chen, Bo Jiang, Hua Zhang, Yujie XuAbstract:In this study, the effects of sorbent addition for in-situ CO2 removal on hydrogen production by sorption-enhanced chemical looping steam reforming (SE-CLSR) of ethanol have been evaluated in an alternating Fixed-Bed Reactor using a mixture of NiO/Al2O3 oxygen carrier catalyst (OC) and CaO based sorbent at moderate operating conditions (T: 600 °C, P: 1.0 atm and S:C: 3.0). The experimental data were compared with chemical equilibrium analysis based on the minimization of Gibbs free energy. The results demonstrated that NiO component in the OC was first reduced by ethanol and the reduced OC was responsible of catalytic steam reforming and water gas shift (WGS) for hydrogen production. The CO2 produced was efficiently removed by CaO based sorbent, also resulting in the process intensification considerably. It appears that the superior molar ratio of sorbent to OC (Ca/Ni) is to be 2.0–3.0 and the highest hydrogen selectivity and feeding conversion were obtained at 3.0 of Ca/Ni ratio. Hydrogen production was inhibited using further high Ca/Ni ratio due to the OC particles were surrounded and diluted by sorbent. The exothermic reactions also provided the heat to raise the temperature of the Reactor. In-situ CO2 removal by solid sorbent promotes ethanol dehydration and C–C carbon bonds cleavage, and thus, the hydrogen production route of conventional CLSR is changed. Continuous high-purity hydrogen production was achieved by integrating the oxidization, steam reforming, WGS, and in situ CO2 capture in an alternating Fixed-Bed Reactor.
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enhanced hydrogen production by sorption enhanced steam reforming from glycerol with in situ co2 removal in a Fixed Bed Reactor
Fuel, 2016Co-Authors: Binlin Dou, Chuan Zhang, Chao Wang, Yongchen Song, Bo Jiang, Haisheng ChenAbstract:For the Fixed-Bed Reactor configuration in the sorption-enhanced steam reforming process (SERP), solid mixture of catalyst and sorbent is stationary and alternatively exposed to reaction and regeneration conditions for multi-cycles by periodically switching the feed gases for enhanced hydrogen production with in-situ CO2 removal. A NiO/NiAl2O4 catalyst was synthesized by the co-precipitation method with rising pH technique and the crystalline spinel phase of NiAl2O4 was formed under the calcination temperature of 900 degrees C. The catalyst was characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), thermo-gravimetric analysis (TGA), and N-2 adsorption-desorption. The non-stoichiometric thermodynamic calculation was carried out to determine the effects of temperature and in-situ CO2 removal on the enhancement of hydrogen production by SERP from glycerol at 425-700 degrees C. The multi-cycles on reaction and regeneration for hydrogen production by SERP from glycerol were performed by NiO/NiAl2O4 catalyst and CaO based sorbent in a Fixed-Bed Reactor. The results showed that hydrogen production by SERP can be clearly divided into three periods, and the experimental gaseous products were compared with non-stoichiometric thermodynamic calculations. It is obvious that H-2 purity was greatly increased, and CO2, CO and CH4 concentrations were reduced by in-situ CO2 removal during the pre-breakthrough period. It is found that enhanced hydrogen production was mainly depended on in-situ CO2 removal. The operation durations for producing high-purity hydrogen of more than 90% were decreased with the increase of the cycles. It may due to the decrease in the reactivity of CaO based sorbent after multi-cycles reaction and regeneration. (C) 2015 Elsevier Ltd. All rights reserved.
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Hydrogen production from chemical looping steam reforming of glycerol by Ni-based oxygen carrier in a Fixed-Bed Reactor
Chemical Engineering Journal, 2015Co-Authors: Bo Jiang, Binlin Dou, Baoguo Du, Haisheng Chen, Chuan Zhang, Chao Wang, Yongchen Song, Yujie XuAbstract:Hydrogen production from chemical looping steam reforming (CLSR) of glycerol was studied by Ni-based oxygen carrier in a Fixed-Bed Reactor. For the Fixed-Bed Reactor configuration, solid Ni-based oxygen carrier is stationary and alternatively exposed to reducing and oxidizing conditions by periodically switching the feed gases. The Ni-based oxygen carrier was prepared by a liquid-state co-precipitation method with rising pH technique and the characterization was performed by X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and N2 adsorption-desorption. Gaseous products and temperature variety during CLSR process by Ni-based oxygen carrier in a Fixed-Bed Reactor were measured, and the thermodynamic equilibrium calculation was also carried out. The results showed that the Ni-based oxygen carrier synthesized has a dual function and can efficiently convert glycerol and steam to H2 by redox reactions. The coexisting reactions of glycerol oxidization (or NiO reduction) and steam reforming occurred before the steady stage of hydrogen production in the fuel feed step, and the conversion of NiO to Ni was obtained. Alternating reduction and oxidation reactions enabled Ni-based oxygen carrier to produce H2 with a concentration of 85% of the equilibrium value at 600°C, and glycerol conversion was up to 99%. The increase of temperature related to the exothermic reactions by Ni-based oxygen carrier in CLSR process was observed in redox cycles.
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high temperature co2 capture using calcium oxide sorbent in a Fixed Bed Reactor
Journal of Hazardous Materials, 2010Co-Authors: Binlin Dou, Yongchen Song, Yingguang Liu, Cong FengAbstract:Abstract The gas–solid reaction and breakthrough curve of CO 2 capture using calcium oxide sorbent at high temperature in a Fixed-Bed Reactor are of great importance, and being influenced by a number of factors makes the characterization and prediction of these a difficult problem. In this study, the operating parameters on reaction between solid sorbent and CO 2 gas at high temperature were investigated. The results of the breakthrough curves showed that calcium oxide sorbent in the Fixed-Bed Reactor was capable of reducing the CO 2 level to near zero level with the steam of 10 vol%, and the sorbent in CaO mixed with MgO of 40 wt% had extremely low capacity for CO 2 capture at 550 °C. Calcium oxide sorbent after reaction can be easily regenerated at 900 °C by pure N 2 flow. The experimental data were analyzed by shrinking core model, and the results showed reaction rates of both fresh and regeneration sorbents with CO 2 were controlled by a combination of the surface chemical reaction and diffusion of product layer.
Haisheng Chen - One of the best experts on this subject based on the ideXlab platform.
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Hydrogen production by sorption-enhanced chemical looping steam reforming of ethanol in an alternating Fixed-Bed Reactor: Sorbent to catalyst ratio dependencies
Energy Conversion and Management, 2018Co-Authors: Binlin Dou, Kaiqiang Wang, Zilong Wang, Guomin Cui, Haisheng Chen, Bo Jiang, Hua Zhang, Yujie XuAbstract:In this study, the effects of sorbent addition for in-situ CO2 removal on hydrogen production by sorption-enhanced chemical looping steam reforming (SE-CLSR) of ethanol have been evaluated in an alternating Fixed-Bed Reactor using a mixture of NiO/Al2O3 oxygen carrier catalyst (OC) and CaO based sorbent at moderate operating conditions (T: 600 °C, P: 1.0 atm and S:C: 3.0). The experimental data were compared with chemical equilibrium analysis based on the minimization of Gibbs free energy. The results demonstrated that NiO component in the OC was first reduced by ethanol and the reduced OC was responsible of catalytic steam reforming and water gas shift (WGS) for hydrogen production. The CO2 produced was efficiently removed by CaO based sorbent, also resulting in the process intensification considerably. It appears that the superior molar ratio of sorbent to OC (Ca/Ni) is to be 2.0–3.0 and the highest hydrogen selectivity and feeding conversion were obtained at 3.0 of Ca/Ni ratio. Hydrogen production was inhibited using further high Ca/Ni ratio due to the OC particles were surrounded and diluted by sorbent. The exothermic reactions also provided the heat to raise the temperature of the Reactor. In-situ CO2 removal by solid sorbent promotes ethanol dehydration and C–C carbon bonds cleavage, and thus, the hydrogen production route of conventional CLSR is changed. Continuous high-purity hydrogen production was achieved by integrating the oxidization, steam reforming, WGS, and in situ CO2 capture in an alternating Fixed-Bed Reactor.
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hydrogen production and reduction of ni based oxygen carriers during chemical looping steam reforming of ethanol in a Fixed Bed Reactor
International Journal of Hydrogen Energy, 2017Co-Authors: Hua Zhang, Kaiqiang Wang, Zilong Wang, Haisheng Chen, Bo Jiang, Yujie XuAbstract:Abstract Hydrogen production and reduction of Ni-based oxygen carriers (OCs) during chemical looping steam reforming (CLSR) of ethanol were studied in a Fixed-Bed Reactor using four OCs with different supports including NiO/SBA-15, NiO/MCM-41, NiO/MMT and NiO/Al2O3. The OCs prepared were characterized by N2 adsorption-desorption, TPR, TPO, XRD, TEM, FTIR and TGA-DSC. The results demonstrated that NiO component in all the OCs was first reduced by ethanol and the reduced OCs were responsible of catalytic steam reforming and water gas shift for hydrogen production. Mesoporous NiO/SBA-15 presented increasing conversion of NiO reduction and the highest selectivity of hydrogen production. The conversion of ethanol increased with reactions proceeding until the highest value is reached after about ∼300s, and the negative steam conversion obtained was resulted from H2O formation from ethanol oxidation by OCs. Compared with MMT and Al2O3 supports, the oxidization of NiO with MCM-41 and SBA-15 supports was very fast and less carbon was formed and deposited. Enhancement in hydrogen production from CLSR process was achieved by in-situ CO2 removal. Shrinking Core model (SCM) based on the constant pattern model for Fixed-Bed Reactor indicated the rates of OCs reduction with ethanol were mainly controlled by surface chemical reaction and product layer diffusion. The reduction process was found to undergo three different rate-limiting stages, and the critical times for changes in the rate-limiting steps were determined.
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enhanced hydrogen production by sorption enhanced steam reforming from glycerol with in situ co2 removal in a Fixed Bed Reactor
Fuel, 2016Co-Authors: Binlin Dou, Chuan Zhang, Chao Wang, Yongchen Song, Bo Jiang, Haisheng ChenAbstract:For the Fixed-Bed Reactor configuration in the sorption-enhanced steam reforming process (SERP), solid mixture of catalyst and sorbent is stationary and alternatively exposed to reaction and regeneration conditions for multi-cycles by periodically switching the feed gases for enhanced hydrogen production with in-situ CO2 removal. A NiO/NiAl2O4 catalyst was synthesized by the co-precipitation method with rising pH technique and the crystalline spinel phase of NiAl2O4 was formed under the calcination temperature of 900 degrees C. The catalyst was characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), thermo-gravimetric analysis (TGA), and N-2 adsorption-desorption. The non-stoichiometric thermodynamic calculation was carried out to determine the effects of temperature and in-situ CO2 removal on the enhancement of hydrogen production by SERP from glycerol at 425-700 degrees C. The multi-cycles on reaction and regeneration for hydrogen production by SERP from glycerol were performed by NiO/NiAl2O4 catalyst and CaO based sorbent in a Fixed-Bed Reactor. The results showed that hydrogen production by SERP can be clearly divided into three periods, and the experimental gaseous products were compared with non-stoichiometric thermodynamic calculations. It is obvious that H-2 purity was greatly increased, and CO2, CO and CH4 concentrations were reduced by in-situ CO2 removal during the pre-breakthrough period. It is found that enhanced hydrogen production was mainly depended on in-situ CO2 removal. The operation durations for producing high-purity hydrogen of more than 90% were decreased with the increase of the cycles. It may due to the decrease in the reactivity of CaO based sorbent after multi-cycles reaction and regeneration. (C) 2015 Elsevier Ltd. All rights reserved.
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Hydrogen production from chemical looping steam reforming of glycerol by Ni-based oxygen carrier in a Fixed-Bed Reactor
Chemical Engineering Journal, 2015Co-Authors: Bo Jiang, Binlin Dou, Baoguo Du, Haisheng Chen, Chuan Zhang, Chao Wang, Yongchen Song, Yujie XuAbstract:Hydrogen production from chemical looping steam reforming (CLSR) of glycerol was studied by Ni-based oxygen carrier in a Fixed-Bed Reactor. For the Fixed-Bed Reactor configuration, solid Ni-based oxygen carrier is stationary and alternatively exposed to reducing and oxidizing conditions by periodically switching the feed gases. The Ni-based oxygen carrier was prepared by a liquid-state co-precipitation method with rising pH technique and the characterization was performed by X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and N2 adsorption-desorption. Gaseous products and temperature variety during CLSR process by Ni-based oxygen carrier in a Fixed-Bed Reactor were measured, and the thermodynamic equilibrium calculation was also carried out. The results showed that the Ni-based oxygen carrier synthesized has a dual function and can efficiently convert glycerol and steam to H2 by redox reactions. The coexisting reactions of glycerol oxidization (or NiO reduction) and steam reforming occurred before the steady stage of hydrogen production in the fuel feed step, and the conversion of NiO to Ni was obtained. Alternating reduction and oxidation reactions enabled Ni-based oxygen carrier to produce H2 with a concentration of 85% of the equilibrium value at 600°C, and glycerol conversion was up to 99%. The increase of temperature related to the exothermic reactions by Ni-based oxygen carrier in CLSR process was observed in redox cycles.
Yujie Xu - One of the best experts on this subject based on the ideXlab platform.
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Hydrogen production by sorption-enhanced chemical looping steam reforming of ethanol in an alternating Fixed-Bed Reactor: Sorbent to catalyst ratio dependencies
Energy Conversion and Management, 2018Co-Authors: Binlin Dou, Kaiqiang Wang, Zilong Wang, Guomin Cui, Haisheng Chen, Bo Jiang, Hua Zhang, Yujie XuAbstract:In this study, the effects of sorbent addition for in-situ CO2 removal on hydrogen production by sorption-enhanced chemical looping steam reforming (SE-CLSR) of ethanol have been evaluated in an alternating Fixed-Bed Reactor using a mixture of NiO/Al2O3 oxygen carrier catalyst (OC) and CaO based sorbent at moderate operating conditions (T: 600 °C, P: 1.0 atm and S:C: 3.0). The experimental data were compared with chemical equilibrium analysis based on the minimization of Gibbs free energy. The results demonstrated that NiO component in the OC was first reduced by ethanol and the reduced OC was responsible of catalytic steam reforming and water gas shift (WGS) for hydrogen production. The CO2 produced was efficiently removed by CaO based sorbent, also resulting in the process intensification considerably. It appears that the superior molar ratio of sorbent to OC (Ca/Ni) is to be 2.0–3.0 and the highest hydrogen selectivity and feeding conversion were obtained at 3.0 of Ca/Ni ratio. Hydrogen production was inhibited using further high Ca/Ni ratio due to the OC particles were surrounded and diluted by sorbent. The exothermic reactions also provided the heat to raise the temperature of the Reactor. In-situ CO2 removal by solid sorbent promotes ethanol dehydration and C–C carbon bonds cleavage, and thus, the hydrogen production route of conventional CLSR is changed. Continuous high-purity hydrogen production was achieved by integrating the oxidization, steam reforming, WGS, and in situ CO2 capture in an alternating Fixed-Bed Reactor.
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hydrogen production and reduction of ni based oxygen carriers during chemical looping steam reforming of ethanol in a Fixed Bed Reactor
International Journal of Hydrogen Energy, 2017Co-Authors: Hua Zhang, Kaiqiang Wang, Zilong Wang, Haisheng Chen, Bo Jiang, Yujie XuAbstract:Abstract Hydrogen production and reduction of Ni-based oxygen carriers (OCs) during chemical looping steam reforming (CLSR) of ethanol were studied in a Fixed-Bed Reactor using four OCs with different supports including NiO/SBA-15, NiO/MCM-41, NiO/MMT and NiO/Al2O3. The OCs prepared were characterized by N2 adsorption-desorption, TPR, TPO, XRD, TEM, FTIR and TGA-DSC. The results demonstrated that NiO component in all the OCs was first reduced by ethanol and the reduced OCs were responsible of catalytic steam reforming and water gas shift for hydrogen production. Mesoporous NiO/SBA-15 presented increasing conversion of NiO reduction and the highest selectivity of hydrogen production. The conversion of ethanol increased with reactions proceeding until the highest value is reached after about ∼300s, and the negative steam conversion obtained was resulted from H2O formation from ethanol oxidation by OCs. Compared with MMT and Al2O3 supports, the oxidization of NiO with MCM-41 and SBA-15 supports was very fast and less carbon was formed and deposited. Enhancement in hydrogen production from CLSR process was achieved by in-situ CO2 removal. Shrinking Core model (SCM) based on the constant pattern model for Fixed-Bed Reactor indicated the rates of OCs reduction with ethanol were mainly controlled by surface chemical reaction and product layer diffusion. The reduction process was found to undergo three different rate-limiting stages, and the critical times for changes in the rate-limiting steps were determined.
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Hydrogen production from chemical looping steam reforming of glycerol by Ni-based oxygen carrier in a Fixed-Bed Reactor
Chemical Engineering Journal, 2015Co-Authors: Bo Jiang, Binlin Dou, Baoguo Du, Haisheng Chen, Chuan Zhang, Chao Wang, Yongchen Song, Yujie XuAbstract:Hydrogen production from chemical looping steam reforming (CLSR) of glycerol was studied by Ni-based oxygen carrier in a Fixed-Bed Reactor. For the Fixed-Bed Reactor configuration, solid Ni-based oxygen carrier is stationary and alternatively exposed to reducing and oxidizing conditions by periodically switching the feed gases. The Ni-based oxygen carrier was prepared by a liquid-state co-precipitation method with rising pH technique and the characterization was performed by X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and N2 adsorption-desorption. Gaseous products and temperature variety during CLSR process by Ni-based oxygen carrier in a Fixed-Bed Reactor were measured, and the thermodynamic equilibrium calculation was also carried out. The results showed that the Ni-based oxygen carrier synthesized has a dual function and can efficiently convert glycerol and steam to H2 by redox reactions. The coexisting reactions of glycerol oxidization (or NiO reduction) and steam reforming occurred before the steady stage of hydrogen production in the fuel feed step, and the conversion of NiO to Ni was obtained. Alternating reduction and oxidation reactions enabled Ni-based oxygen carrier to produce H2 with a concentration of 85% of the equilibrium value at 600°C, and glycerol conversion was up to 99%. The increase of temperature related to the exothermic reactions by Ni-based oxygen carrier in CLSR process was observed in redox cycles.
Bo Jiang - One of the best experts on this subject based on the ideXlab platform.
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Hydrogen production by sorption-enhanced chemical looping steam reforming of ethanol in an alternating Fixed-Bed Reactor: Sorbent to catalyst ratio dependencies
Energy Conversion and Management, 2018Co-Authors: Binlin Dou, Kaiqiang Wang, Zilong Wang, Guomin Cui, Haisheng Chen, Bo Jiang, Hua Zhang, Yujie XuAbstract:In this study, the effects of sorbent addition for in-situ CO2 removal on hydrogen production by sorption-enhanced chemical looping steam reforming (SE-CLSR) of ethanol have been evaluated in an alternating Fixed-Bed Reactor using a mixture of NiO/Al2O3 oxygen carrier catalyst (OC) and CaO based sorbent at moderate operating conditions (T: 600 °C, P: 1.0 atm and S:C: 3.0). The experimental data were compared with chemical equilibrium analysis based on the minimization of Gibbs free energy. The results demonstrated that NiO component in the OC was first reduced by ethanol and the reduced OC was responsible of catalytic steam reforming and water gas shift (WGS) for hydrogen production. The CO2 produced was efficiently removed by CaO based sorbent, also resulting in the process intensification considerably. It appears that the superior molar ratio of sorbent to OC (Ca/Ni) is to be 2.0–3.0 and the highest hydrogen selectivity and feeding conversion were obtained at 3.0 of Ca/Ni ratio. Hydrogen production was inhibited using further high Ca/Ni ratio due to the OC particles were surrounded and diluted by sorbent. The exothermic reactions also provided the heat to raise the temperature of the Reactor. In-situ CO2 removal by solid sorbent promotes ethanol dehydration and C–C carbon bonds cleavage, and thus, the hydrogen production route of conventional CLSR is changed. Continuous high-purity hydrogen production was achieved by integrating the oxidization, steam reforming, WGS, and in situ CO2 capture in an alternating Fixed-Bed Reactor.
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hydrogen production and reduction of ni based oxygen carriers during chemical looping steam reforming of ethanol in a Fixed Bed Reactor
International Journal of Hydrogen Energy, 2017Co-Authors: Hua Zhang, Kaiqiang Wang, Zilong Wang, Haisheng Chen, Bo Jiang, Yujie XuAbstract:Abstract Hydrogen production and reduction of Ni-based oxygen carriers (OCs) during chemical looping steam reforming (CLSR) of ethanol were studied in a Fixed-Bed Reactor using four OCs with different supports including NiO/SBA-15, NiO/MCM-41, NiO/MMT and NiO/Al2O3. The OCs prepared were characterized by N2 adsorption-desorption, TPR, TPO, XRD, TEM, FTIR and TGA-DSC. The results demonstrated that NiO component in all the OCs was first reduced by ethanol and the reduced OCs were responsible of catalytic steam reforming and water gas shift for hydrogen production. Mesoporous NiO/SBA-15 presented increasing conversion of NiO reduction and the highest selectivity of hydrogen production. The conversion of ethanol increased with reactions proceeding until the highest value is reached after about ∼300s, and the negative steam conversion obtained was resulted from H2O formation from ethanol oxidation by OCs. Compared with MMT and Al2O3 supports, the oxidization of NiO with MCM-41 and SBA-15 supports was very fast and less carbon was formed and deposited. Enhancement in hydrogen production from CLSR process was achieved by in-situ CO2 removal. Shrinking Core model (SCM) based on the constant pattern model for Fixed-Bed Reactor indicated the rates of OCs reduction with ethanol were mainly controlled by surface chemical reaction and product layer diffusion. The reduction process was found to undergo three different rate-limiting stages, and the critical times for changes in the rate-limiting steps were determined.
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enhanced hydrogen production by sorption enhanced steam reforming from glycerol with in situ co2 removal in a Fixed Bed Reactor
Fuel, 2016Co-Authors: Binlin Dou, Chuan Zhang, Chao Wang, Yongchen Song, Bo Jiang, Haisheng ChenAbstract:For the Fixed-Bed Reactor configuration in the sorption-enhanced steam reforming process (SERP), solid mixture of catalyst and sorbent is stationary and alternatively exposed to reaction and regeneration conditions for multi-cycles by periodically switching the feed gases for enhanced hydrogen production with in-situ CO2 removal. A NiO/NiAl2O4 catalyst was synthesized by the co-precipitation method with rising pH technique and the crystalline spinel phase of NiAl2O4 was formed under the calcination temperature of 900 degrees C. The catalyst was characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), thermo-gravimetric analysis (TGA), and N-2 adsorption-desorption. The non-stoichiometric thermodynamic calculation was carried out to determine the effects of temperature and in-situ CO2 removal on the enhancement of hydrogen production by SERP from glycerol at 425-700 degrees C. The multi-cycles on reaction and regeneration for hydrogen production by SERP from glycerol were performed by NiO/NiAl2O4 catalyst and CaO based sorbent in a Fixed-Bed Reactor. The results showed that hydrogen production by SERP can be clearly divided into three periods, and the experimental gaseous products were compared with non-stoichiometric thermodynamic calculations. It is obvious that H-2 purity was greatly increased, and CO2, CO and CH4 concentrations were reduced by in-situ CO2 removal during the pre-breakthrough period. It is found that enhanced hydrogen production was mainly depended on in-situ CO2 removal. The operation durations for producing high-purity hydrogen of more than 90% were decreased with the increase of the cycles. It may due to the decrease in the reactivity of CaO based sorbent after multi-cycles reaction and regeneration. (C) 2015 Elsevier Ltd. All rights reserved.
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Hydrogen production from chemical looping steam reforming of glycerol by Ni-based oxygen carrier in a Fixed-Bed Reactor
Chemical Engineering Journal, 2015Co-Authors: Bo Jiang, Binlin Dou, Baoguo Du, Haisheng Chen, Chuan Zhang, Chao Wang, Yongchen Song, Yujie XuAbstract:Hydrogen production from chemical looping steam reforming (CLSR) of glycerol was studied by Ni-based oxygen carrier in a Fixed-Bed Reactor. For the Fixed-Bed Reactor configuration, solid Ni-based oxygen carrier is stationary and alternatively exposed to reducing and oxidizing conditions by periodically switching the feed gases. The Ni-based oxygen carrier was prepared by a liquid-state co-precipitation method with rising pH technique and the characterization was performed by X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and N2 adsorption-desorption. Gaseous products and temperature variety during CLSR process by Ni-based oxygen carrier in a Fixed-Bed Reactor were measured, and the thermodynamic equilibrium calculation was also carried out. The results showed that the Ni-based oxygen carrier synthesized has a dual function and can efficiently convert glycerol and steam to H2 by redox reactions. The coexisting reactions of glycerol oxidization (or NiO reduction) and steam reforming occurred before the steady stage of hydrogen production in the fuel feed step, and the conversion of NiO to Ni was obtained. Alternating reduction and oxidation reactions enabled Ni-based oxygen carrier to produce H2 with a concentration of 85% of the equilibrium value at 600°C, and glycerol conversion was up to 99%. The increase of temperature related to the exothermic reactions by Ni-based oxygen carrier in CLSR process was observed in redox cycles.
Siyi Luo - One of the best experts on this subject based on the ideXlab platform.
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syngas production by catalytic steam gasification of municipal solid waste in Fixed Bed Reactor
Energy, 2012Co-Authors: Siyi Luo, Yangmin ZhouAbstract:Abstract The catalytic steam gasification of municipal solid waste for syngas production was conducted in a lab-scale Fixed-Bed Reactor. The influence of the Reactor temperature, steam to carbon ratio (S/C) and catalyst type (NiO/γ-Al2O3 or calcined dolomite) on the gas yield, gas composition, H2/CO molar ratio and carbon conversion efficiency were investigated. The results indicated that increasing Reactor temperature resulted in greater gas production in the initial pyrolysis and improved endothermic reactions (gasification of char, catalytic cracking and reforming of tar), which resulted in the increase of syngas yield. Compared with MSW catalytic pyrolysis, the introduction of steam leads to more tar and char participating in steam gasification, which resulted in a rapid increase of syngas yield and carbon conversion efficiency. NiO/γ-Al2O3 catalyst revealed better catalytic performance for the cracking of tar than calcined dolomite. The highest H2 content (54.22%) and gas yield (1.75 N m3/kg) were achieved at 900 °C, S/C being 2.41 with NiO/γ-Al2O3 as catalyst.
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effect of particle size on pyrolysis of single component municipal solid waste in Fixed Bed Reactor
International Journal of Hydrogen Energy, 2010Co-Authors: Siyi Luo, Bo Xiao, Shiming LiuAbstract:Abstract According to the differences in components, three representative components (plastic, kitchen garbage and wood) in municipal solid waste (MSW) were pyrolyzed in a Fixed Bed Reactor to evaluate the influence of particle size on pyrolysis performance of single-component municipal solid waste (MSW). The Bed temperature was set at 800°C and each sample was separated into three different size fractions (0–5 mm, 5–10 mm and 10–20 mm). The results show for all the samples particle size has an effect on pyrolysis product yields and composition: smaller particle size results in higher gas yield with less tar and char; the decrease of particle size can increase H 2 and CO contents of gas, as well as the ash and carbon element contents in the char. And the influence is the much more significant for sample with higher Fixed carbon and ash contents, such as kitchen garbage, and less for sample with higher volatile content, plastic in the test.
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hydrogen rich gas from catalytic steam gasification of biomass in a Fixed Bed Reactor influence of temperature and steam on gasification performance
International Journal of Hydrogen Energy, 2009Co-Authors: Siyi Luo, Bo Xiao, Shiming Liu, Xianjun GuoAbstract:The catalytic steam gasification of biomass was carried out in a lab-scale Fixed Bed Reactor in order to evaluate the effects of temperatures and the ratio of steam to biomass (S/B) on the gasification performance. The Bed temperature was varied from 600 to 900 and the S/B from 0 to 2.80. The results show that higher temperature contributes to more hydrogen production. The introduction of steam improves the dry gas yield and carbon conversion efficiency. But excessive steam will lower hydrogen content and degrade fuel gas quality. As S/B are 2.10, the hydrogen content reach the maximum, up to 52.7%.