Dry reforming of methane over silica zeolite-encapsulated Ni-based catalysts: Effect of preparation method, support structure and Ni content on catalytic performance

Abstract

Dry reforming of methane (DRM) is a prospective technology for efficient utilization of CH4 and CO2, with the essential challenge being the design and synthesis of efficient catalysts. In this research, serial encapsulated Ni-based catalysts (xNi@S-1, x = 5, 7, 10) by silica zeolite (S-1) were prepared successfully. The effects of support structure, preparation method and Ni content upon the catalytic performance for DRM were investigated and diverse characterizations were utilized for revealing structural features of as-prepared catalysts. Encapsulated 7Ni@S-1 catalyst prepared using the one-pot hydrothermal method could acquire more homogeneously dispersed metallic Ni particles and more Ni species including Ni0, NiO, 1:1/2:1 Ni phyllosilicates that could facilitate forming stable Ni0 sites and Ni2+-O2- ion pairs for adsorption and activation of CH4 and CO2, respectively. Hence, 7Ni@S-1 still maintained the highest CH4 and CO2 conversions of 57.9% and 88.6% and H2/CO molar ratio of 0.90 after 52 h stability tests.