焙烧温度对甲烷催化部分氧化Ni/MgO-Al2O3催化剂结构和性能的影响

The effects of calcination temperature on the properties of Ni/MgO-Al2O3 were studied by the means of XRD, TPR, BET，TG and catalytic performance evaluation. With the increase of calcination temperature of the catalysts, the interaction between nickel species and support became stronger, and NiAl2O4, MgAl2O4 spinel and NiMgO2 formed. Compared withγ-alumina, the Ni/MgO-Al2O3 catalysts showed larger specific surface area even at higher calcination temperature due to the formation of spinel. In the partial oxidation of methane to syngas, the Ni/MgO-Al2O3 catalysts calcinated at higher temperature exhibited better stability under the conditions of atmospheric pressure, 1 083 K, CH4/O2=1.8 and 2.66×105 h－1. Whether Ni/MgO-Al2O3 catalysts were calcined at low or high temperature, they all showed higher resistance to coking. In addition, the hotspot temperature of the catalytic bed for the catalysts calcinated at high temperature decreased, which benefits to prevent the catalysts from sintering.