The sorption-enhanced steam reforming process of methanol（SESRP-Me OH） to produce high-purity H2 was thermodynamically and experimentally studied.Thermodynamic calculations showed that at a CO2 adsorption ratio of 9...The sorption-enhanced steam reforming process of methanol（SESRP-Me OH） to produce high-purity H2 was thermodynamically and experimentally studied.Thermodynamic calculations showed that at a CO2 adsorption ratio of 95%,product gas contains 98.36% H2,32.8 ppm CO under temperature of 130°C and steam-to-methanol（S/M） molar ratio of 2.However,without adsorption-enhanced,the product gas contains nearly 74.99% H2 with 24.96% CO2 and 525 ppm CO.To verify the thermodynamic calculation results,experiments were performed in a fixed-bed reactor loaded with commercial Cu O/Zn O/Al2O3 methanol reforming catalyst and 22% K2CO3-promoted hydrotalcite as CO2 adsorbent.Experimental results showed that 99.61% H2 could be obtained by SESRP-Me OH at reaction temperature of 230°C and S/M of 2.Under the same CH3 OH conversion,the reaction temperature decreased by almost 50°C and H2 concentration increased of more than 20%using SESRP-Me OH compared with solely steam reforming of methanol.The characterization of the adsorbent and catalyst showed that the adsorbent showed good stability while the catalyst was seriously sintered under the high regeneration temperature of the adsorbent.展开更多
Hydrogen is an indispensable energy carrier for the sustainable development of human society.Nevertheless,its storage,transportation,and in situ generation still face significant challenges.Methanol can be used as an ...Hydrogen is an indispensable energy carrier for the sustainable development of human society.Nevertheless,its storage,transportation,and in situ generation still face significant challenges.Methanol can be used as an intermediate carrier for hydrogen supplies,providing hydrogen energy through instant methanol conversion.In this study,a sorption-enhanced,chemical-looping,oxidative steam methanol-reforming(SECLOSRM)process is proposed using CuO–MgO for the on-board hydrogen supply,which could be a promising method for safe and efficient hydrogen production.Aspen Plus software was used for feasibility verification and parameter optimization of the SECL-OSRM process.The effects of CuO/CH_(3)OH,MgO/CH_(3)OH,and H_(2)O/CH_(3)OH mole ratios and of temperature on H_(2)production rate,H utilization efficiency,CH_(3)OH conversion,CO concentration,and system heat balance are discussed thoroughly.The results indicate that the system can be operated in autothermal conditions with high-purity hydrogen(99.50 vol%)and ultra-low-concentration CO(<50 ppm)generation,which confirms the possibility of integrating low-temperature proton-exchange membrane fuel cells(LT-PEFMCs)with the SECL-OSRM process.The simulation results indicate that the CO can be modulated in a lower concentration by reducing the temperature and by improving the H_(2)O/CH_(3)OH and MgO/CH_(3)OH mole ratios.展开更多
In response to the urgent global need to address climate change,reduce emissions,and ensure energy security,hydrogen plays a crucial role in the global energy transitio n.However,traditional hydrogen production method...In response to the urgent global need to address climate change,reduce emissions,and ensure energy security,hydrogen plays a crucial role in the global energy transitio n.However,traditional hydrogen production methods,such as fossil fuel-based steam reforming and water electrolysis,face significant environmental and economic challenges.As an abundant renewable resource,biomass has attracted much attention for hydrogen production technology,particularly sorption-enhanced steam reforming(SESR).This technology combines the principles of chemical equilibrium and sorption to capture CO_(2) using solid sorbents,thereby enhancing the efficiency and purity of hydrogen production from biomass-derived syngas.It offers advantages such as reduced costs,lower energy consumption,decreased emissions,and cu stomization for specific applications.Although SESR technology has demonstrated excellent hydrogen production performance,existing reviews mainly focus on model compounds and still lack critical analysis of its performance in real biomass application scenarios.This review provides a critical summary of the research progress of biomass feedstocks and model compounds SESR for hydrogen production,detailing the effects of feedstock characteristics,temperature,steam ratio,CO_(2) sorbent(CaO,alkali metal ceramics,and hydrotalcite),and catalysts on gas yield.In addition,it further emphasizes the research progress of advanced sorption-catalysis bifunctional composite materials and discusses the coupling application of SESR technology with other processes.The review concludes by highlighting the outstanding challenges of SESR technology and focusing on future research directions,aiming to provide theoretical support and insights for the further development of sorption-enhanced biomass hydrogen production technology.展开更多
A two-dimensional transient model has been developed to describe the catalytic methane reforming （MSR） coupled with simultaneous CO2 removal by different absorbents under non-isothermal, non-isobaric and non-adiabat...A two-dimensional transient model has been developed to describe the catalytic methane reforming （MSR） coupled with simultaneous CO2 removal by different absorbents under non-isothermal, non-isobaric and non-adiabatic operating conditions. The influences of temperature, pressure and steam/carbon （S/C） on enhancement were taken into account. The results showed that the hydrogen mole fraction （dry basis） higher than 94% could be achieved using Li4SiO4, CaO, and HTC as CO2 acceptors at the operating conditions of 550~C and 0.1 MPa. When the reaction temperature varied from 500℃ to 600℃, the initial CO2 capture rates were HTC〉CaO〉Li4SiO4〉LizZrO3, and the saturation rates HTC〉CaO〉Li4SiOg〉Li2ZrO3. Increasing the reaction temperature would improve the CO2 capture rate and available CO2 capacity. For Li4SiO4, although the adsorbing rate increased as the operating temperature increased, the capacity almost did not change. At 550℃, increasing the working pressure could promote the enhancing factors of Li4SiO4,Li2ZrO3 and HTC. There was an optimal steam/carbon ratio between 2-4.5 such that all CaO, Li4SiO4, HTC and Li2ZrO3 would obtain the biggest enhancement for H2 production at the pre-breakthrough stage.展开更多
The sorption-enhanced method can change the thermodynamic equilibrium by absorbing CO_(2).However,it also brings about the problems of high regeneration temperature of adsorbent and large regeneration energy consumpti...The sorption-enhanced method can change the thermodynamic equilibrium by absorbing CO_(2).However,it also brings about the problems of high regeneration temperature of adsorbent and large regeneration energy consumption.In order to study the impact of enhanced adsorption methods on the overall energy cost of the system in the hydrogen production process,this paper analyzes and compares steam methane reforming and reactive adsorption-enhanced steam methane reforming with the energy consumption of hydrogen production products as the evaluation index.The results showed that the energy consumption per unit hydrogen production decreased from 276.21 MJ/kmol to 131.51 MJ/kmol,and the decomposition rate of H2O increased by more than 20%after the addition of adsorption enhancement method.It is proved that the advantage of sorption enhanced method on pre-separation of CO_(2)in the product makes up for the disadvantage of energy consumption of adsorbent regeneration.In addition,the ability of the process to obtain H element is improved by the high decomposition rate of H2O,which realizes a more rational distribution of the element.展开更多
Hydrogen is considered a secondary source of energy,commonly referred to as an energy carrier.It has the highest energy content when compared to other common fuels by weight,having great potential for further developm...Hydrogen is considered a secondary source of energy,commonly referred to as an energy carrier.It has the highest energy content when compared to other common fuels by weight,having great potential for further development.Hydrogen can be produced from various domestic resources but,based on the fossil resource conditions in China,coal-based hydrogen energy is considered to be the most valuable,because it is not only an effective way to develop clean energy,but also a proactive exploration of the clean usage of traditional coal resources.In this article,the sorption-enhanced water-gas shift technology in the coal-to-hydrogen section and the hydrogen-storage and transport technology with liquid aromatics are introduced and basic mechanisms,technical advantages,latest progress and future R&D focuses of hydrogen-production and storage processes are listed and discussed.As a conclusion,after considering the development frame and the business characteristics of CHN Energy Group,a conceptual architecture for developing coal-based hydrogen energy and the corresponding supply chain,is proposed.展开更多
文摘The sorption-enhanced steam reforming process of methanol（SESRP-Me OH） to produce high-purity H2 was thermodynamically and experimentally studied.Thermodynamic calculations showed that at a CO2 adsorption ratio of 95%,product gas contains 98.36% H2,32.8 ppm CO under temperature of 130°C and steam-to-methanol（S/M） molar ratio of 2.However,without adsorption-enhanced,the product gas contains nearly 74.99% H2 with 24.96% CO2 and 525 ppm CO.To verify the thermodynamic calculation results,experiments were performed in a fixed-bed reactor loaded with commercial Cu O/Zn O/Al2O3 methanol reforming catalyst and 22% K2CO3-promoted hydrotalcite as CO2 adsorbent.Experimental results showed that 99.61% H2 could be obtained by SESRP-Me OH at reaction temperature of 230°C and S/M of 2.Under the same CH3 OH conversion,the reaction temperature decreased by almost 50°C and H2 concentration increased of more than 20%using SESRP-Me OH compared with solely steam reforming of methanol.The characterization of the adsorbent and catalyst showed that the adsorbent showed good stability while the catalyst was seriously sintered under the high regeneration temperature of the adsorbent.
基金supported by the National Key R&D Program of China(2018YFE0111100)National Natural Science Foundation of China(52106193,21908162)+2 种基金the Natural Science Foundation of Hunan Province(2021JJ40756)the Science and Technology Innovation Program of Hunan Province(2020GK2070)the Innovation-Driven Project of Central South University(2020CX008)
文摘Hydrogen is an indispensable energy carrier for the sustainable development of human society.Nevertheless,its storage,transportation,and in situ generation still face significant challenges.Methanol can be used as an intermediate carrier for hydrogen supplies,providing hydrogen energy through instant methanol conversion.In this study,a sorption-enhanced,chemical-looping,oxidative steam methanol-reforming(SECLOSRM)process is proposed using CuO–MgO for the on-board hydrogen supply,which could be a promising method for safe and efficient hydrogen production.Aspen Plus software was used for feasibility verification and parameter optimization of the SECL-OSRM process.The effects of CuO/CH_(3)OH,MgO/CH_(3)OH,and H_(2)O/CH_(3)OH mole ratios and of temperature on H_(2)production rate,H utilization efficiency,CH_(3)OH conversion,CO concentration,and system heat balance are discussed thoroughly.The results indicate that the system can be operated in autothermal conditions with high-purity hydrogen(99.50 vol%)and ultra-low-concentration CO(<50 ppm)generation,which confirms the possibility of integrating low-temperature proton-exchange membrane fuel cells(LT-PEFMCs)with the SECL-OSRM process.The simulation results indicate that the CO can be modulated in a lower concentration by reducing the temperature and by improving the H_(2)O/CH_(3)OH and MgO/CH_(3)OH mole ratios.
基金supported by the National Natural Science Foundation of China(No.52276193)。
文摘In response to the urgent global need to address climate change,reduce emissions,and ensure energy security,hydrogen plays a crucial role in the global energy transitio n.However,traditional hydrogen production methods,such as fossil fuel-based steam reforming and water electrolysis,face significant environmental and economic challenges.As an abundant renewable resource,biomass has attracted much attention for hydrogen production technology,particularly sorption-enhanced steam reforming(SESR).This technology combines the principles of chemical equilibrium and sorption to capture CO_(2) using solid sorbents,thereby enhancing the efficiency and purity of hydrogen production from biomass-derived syngas.It offers advantages such as reduced costs,lower energy consumption,decreased emissions,and cu stomization for specific applications.Although SESR technology has demonstrated excellent hydrogen production performance,existing reviews mainly focus on model compounds and still lack critical analysis of its performance in real biomass application scenarios.This review provides a critical summary of the research progress of biomass feedstocks and model compounds SESR for hydrogen production,detailing the effects of feedstock characteristics,temperature,steam ratio,CO_(2) sorbent(CaO,alkali metal ceramics,and hydrotalcite),and catalysts on gas yield.In addition,it further emphasizes the research progress of advanced sorption-catalysis bifunctional composite materials and discusses the coupling application of SESR technology with other processes.The review concludes by highlighting the outstanding challenges of SESR technology and focusing on future research directions,aiming to provide theoretical support and insights for the further development of sorption-enhanced biomass hydrogen production technology.
基金supported by the National Natural Science Foundation of China (Grant Nos. 40972102, 50906031)the National Basic Research Program of China ("973" Project) (Grant No. 2010CB227003)
文摘A two-dimensional transient model has been developed to describe the catalytic methane reforming （MSR） coupled with simultaneous CO2 removal by different absorbents under non-isothermal, non-isobaric and non-adiabatic operating conditions. The influences of temperature, pressure and steam/carbon （S/C） on enhancement were taken into account. The results showed that the hydrogen mole fraction （dry basis） higher than 94% could be achieved using Li4SiO4, CaO, and HTC as CO2 acceptors at the operating conditions of 550~C and 0.1 MPa. When the reaction temperature varied from 500℃ to 600℃, the initial CO2 capture rates were HTC〉CaO〉Li4SiO4〉LizZrO3, and the saturation rates HTC〉CaO〉Li4SiOg〉Li2ZrO3. Increasing the reaction temperature would improve the CO2 capture rate and available CO2 capacity. For Li4SiO4, although the adsorbing rate increased as the operating temperature increased, the capacity almost did not change. At 550℃, increasing the working pressure could promote the enhancing factors of Li4SiO4,Li2ZrO3 and HTC. There was an optimal steam/carbon ratio between 2-4.5 such that all CaO, Li4SiO4, HTC and Li2ZrO3 would obtain the biggest enhancement for H2 production at the pre-breakthrough stage.
基金the National Key R&D Program of China(2019YFC1906802)for the financial support.
文摘The sorption-enhanced method can change the thermodynamic equilibrium by absorbing CO_(2).However,it also brings about the problems of high regeneration temperature of adsorbent and large regeneration energy consumption.In order to study the impact of enhanced adsorption methods on the overall energy cost of the system in the hydrogen production process,this paper analyzes and compares steam methane reforming and reactive adsorption-enhanced steam methane reforming with the energy consumption of hydrogen production products as the evaluation index.The results showed that the energy consumption per unit hydrogen production decreased from 276.21 MJ/kmol to 131.51 MJ/kmol,and the decomposition rate of H2O increased by more than 20%after the addition of adsorption enhancement method.It is proved that the advantage of sorption enhanced method on pre-separation of CO_(2)in the product makes up for the disadvantage of energy consumption of adsorbent regeneration.In addition,the ability of the process to obtain H element is improved by the high decomposition rate of H2O,which realizes a more rational distribution of the element.
文摘Hydrogen is considered a secondary source of energy,commonly referred to as an energy carrier.It has the highest energy content when compared to other common fuels by weight,having great potential for further development.Hydrogen can be produced from various domestic resources but,based on the fossil resource conditions in China,coal-based hydrogen energy is considered to be the most valuable,because it is not only an effective way to develop clean energy,but also a proactive exploration of the clean usage of traditional coal resources.In this article,the sorption-enhanced water-gas shift technology in the coal-to-hydrogen section and the hydrogen-storage and transport technology with liquid aromatics are introduced and basic mechanisms,technical advantages,latest progress and future R&D focuses of hydrogen-production and storage processes are listed and discussed.As a conclusion,after considering the development frame and the business characteristics of CHN Energy Group,a conceptual architecture for developing coal-based hydrogen energy and the corresponding supply chain,is proposed.
