| As a useful chemical material and a clean energy, hydrogen plays an important role in the progress of human civilization. The aim of this paper is to produce hydrogen by sorption-enhanced steam methane reforming. By introducing the sorption-enhanced effect, high purity hydrogen will be obtained and the consumption of resources and energy can be greatly decreased. According to Le Chatelier’s principle, if CO2is moved once it is formed, the reforming and water-gas shift reactions will proceed beyond the conventional thermodynamic limits and more methane would be converted to hydrogen. Meanwhile, the reaction temperature will decrease significantly, and the reaction and separation units will probably be integrated into a single unit.First, Tthe reaction activity and stability of Ni0.5Mg2.5Al catalyst and CCAN-80sorbent are investigated, and the carbonation kinetics of model of CO2absorbed by the CCAN-80sorbent is studied by using a modified ion reaction model and a modified apparent kinetic model, which is also extended to predicted the multi-cycle process. Second, the sorption-enhanced steam methane reforming experiments are conducted by using the Nio.5Mg2.5Al catalyst and the CCAN-80sorbent. Some key factors influencing the SESMR process, such as reaction temperature, H2O/CH4molar ratio, sorbent/catalyst weight ratio, usage patterns of catalyst and sorbent, are analyzed by thermodynamics and investigated by experiments, based on which, the optimal operation conditions are obtained.In order to obtain novel CaO-based sorbents with higher activity than CCAN-80, a series of sorbents are prepared by using the sol-gel method, and organic calcium salts and aluminum isopropoxide are used as precursors. The results show that the performance (activity and stability) of CLSG-90and CLSG-80sorbents is better than that of CCAN-80.The experimental results, model parameters and theoretical analysis obtained in this thesis are anticipated to be useful for the industrial SESMR process. |
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