Modification of Ni/MCF catalyst and its catalytic performance for dry reforming of methane

Synthesis gas (H2/CO), an important chemical raw material, is produced efficiently by dry reforming of methane. The Ni-based catalyst is widely studied because of its abundant reserves, low price and certain catalytic performance. However, the sintering and carbon deposition problems of Ni-based catalysts have not been solved. In order to solve the problem of sintering and carbon deposition of Ni-based catalyst in dry reforming of methane reaction, a metal-organic framework (MOFs) was formed with 2-methylimidazole and Ni2+, and a Ni-based catalyst with strong metal-support interaction was constructed on a nitridized mesoporous silicon foam (MCF) support with MOFs as the precursor. XRD﹑TEM﹑BET﹑H2-TPR﹑XPS﹑TG and other characterization results show that The N doping modification of MCF support by temperature programmed nitridation can improve the dispersion of active metal, reduce the particle size, enhance the metal-support interaction force, reduce the catalyst reduction degree, enhance the metal-support electron interaction force, and increase the content of high price state Niδ+ on the catalyst surface. The catalyst precursor was modified into a three-dimensional metal-organic framework structure by the complexation of 2-methylimidazole and Ni2+. After calcination by high temperature air, an embedded octahedral nickel silicate species was formed on the catalyst surface. The active metal in nickel silicate species is mainly in the form of high price Niδ+ and highly dispersed on the catalyst surface, showing strong metal-support interaction. N doping modified MCF support and 2-methylimidazole modified catalyst precursor can improve the performance of catalyst more significantly. At 700℃, the conversion of CH4 and CO2 of Ni/N-MCF-MI catalyst is 78% and 83%, respectively, and the reaction performance is stable for 10 h, with good carbon deposition and sintering resistance.