| Hydrogen is considered to be a promising alternative fuel for automobile in the future, characterized by abundant resource, zero contamination, renewability and high energy density. As the development of fuel cell and the automobiles powered by electricity, much concern was focused on the research of technology for on-board hydrogen energy system and the construction of the infrastructure. In this paper, we studied the dehydrogenation of cyclohexane, and hopefully can contribute to the design of the on-board hydrogen energy system in future.From the aspect of energy balance, the paper investigated the dehydrogenation of cyclohexane catalyzed by Raney-Ni under multiphase condition. The influences of reaction temperature and reactant supply on the dehydrogenation were researched. The results show that energy balance serves as the key to multiphase reaction. The ideal reaction condition should be like this where the condensed liquid spreads over the surface of the catalyst as liquid film, and then dehydrogenates. After the reaction, the product and the unreacted cyclohexane can vaporize quickly and leave from the catalyst surface. Hence, the reverse reaction can be restrained. The condition above is controlled by energy balance when the energy supplied by the system is equivalent to the sum of the energy of heating the reactant to dehydrogenation temperature, the energy absorbed by the reaction and the energy needed for vaporization of the product and the unreacted cyclohexane.Dehydrogenation of cyclohexane catalyzed by hydrogen storage alloy was also studied. The experimental data reveal that LaNi4Mn treated by aqueous solution of NH4F has good catalytic performance on the dehydrogenation of cyclohexane. Analysis of the morphology of the alloy was carried out by SEM.The dehydrogenation kinetics of cyclohexane was also analyzed. The results fit well with theories and the catalytic performance of Raney-Ni is superior to that of LaNi4Mn.
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