Highly anti-sintering and anti-coking ordered mesoporous silica carbide supported nickel catalyst for high temperature CO methanation

The inhibition of sintering and coking of supported nickel catalysts remains a great challenge in high-temperature carbon-monoxide (CO) methanation. Ordered mesoporous silica carbide (OM-SiC) was fabricated via a nanocasting technique as a nickel catalyst support for CO methanation. Compared with either SiC or SBA-15 supported nickel catalysts, the Ni/OM-SiC exhibited the best activity for CO methanation from 240 to 600 degrees C, originated from the highest dispersion of Ni. Below 800 degrees C, 1.0 MPa, and a gas hourly space velocity (GHSV) of 15,000 mL g(-1) h(-1), a superior activity is close to the theoretical values. In addition, the Ni/OM-SiC catalyst shows far superior anti-coking and anti-sintering properties than the other two kinds of catalysts. The improved catalytic performance can be attributed to a unique pore structure that offers a spatial confinement effect for the nickel particles, and the high thermal conductivity that avoids the formation of hot-spots during reaction. These findings are helpful to develop an efficient nickel-based methanation catalyst to produce synthetic natural gas.