A basic assessment of the reactivity of Ni catalysts in the decomposition of methane for the production of 'CO_x-free'hydrogen for fuel cells application

摘要

The hydrogen production through the decomposition of methane into hydrogen and carbon on Ni supported catalysts followed by catalyst regeneration in oxidative atmosphere was evaluated.Typical temperature programmed catalytic reaction(TPCR)results revealed that the nature of the carrier slightly affects the onset temperature of CH_4 decomposition,while catalytic performance and regeneration capacity in O_2 or CO_2 streams depend on dispersion and morphology of the active phase.The"structure-sensitive"character of methane decomposition reaction has been confirmed.TEM analyses of the"spent"catalysts revealed that both"filamentous"and"encapsulating"carbon species were formed under isothermal conditions at 823 K,the last being responsible for catalyst deactivation.