Fibrous silica mesoporous ZSM-5 for carbon monoxide methanation

A core-shell fibrous silica mesoporous ZSM-5 (FmZSM-5) has been developed by employing microemulsion system coupled with zeolite crystal-seed crystallization method and unprecedented applied in CO methanation. The FmZSM-5 showed greatly enhanced catalytic activity with the rate of CO conversion (0.0708 mu mol-CO/m(2) s) and the rate of CH4 formation (0.0488 mu mol-CH4/m(2) s) at 723 K, which is two-fold higher than that of the conventional recrystallized mZSM-5 (RmZSM-5). Besides, it showed high stability with no sign of deactivation up to 50 h. The presence of oxygen vacancies led to the increase in interparticle porosity, basicity, and CO and H-2 adsorption sites which are believed to be the keys for remarkably improved in CO methanation. Additionally, the influence of diffusion limitation was indicated to be negligible. Such a unique core-shell fibrous silica mesoporous ZSM-5 and their excellent catalytic properties suggest the significant application possibilities in base-catalyzed reaction especially in the production of methane. (C) 2016 Elsevier B.V. All rights reserved.