Coke-resistant Ni@SiO2 catalyst for dry reforming of methane

Abstract

Nanostructured Ni@SiO2 core–shell catalyst is prepared from nickel oxide nanoparticles by a facile method. Calcination of as-synthesized core–shell nanoparticles creates a micro/meso-porous structure in the amorphous silica shell. The catalytic performance of core–shell catalyst toward dry reforming of methane was first evaluated in a thermogravimeter coupled with a mass spectrometer. Coking is negligible in a reforming period of 40h on stream at 850°C, while more than 0.32gcokegcat−1 is produced on a commercial Ni-based reforming catalyst in 6.4h at the same reforming condition. Dry reforming was also performed in a continuous flow, fixed-bed reactor at 750°C. Characterization of spent catalyst further confirms that Ni@SiO2 catalyst has high coke-resistance for dry reforming. The amount of coke deposited on the core–shell catalyst in 24.5h is 0.012gcokegcat−1.