LAUSR

Abstract This work studies the effect of Ni/Co ratio and calcination temperature on the performance of trimetallic Ni-Co-Ru catalysts supported on MgO-Al2O3. Higher activity was achieved with higher Ni/Co ratios, and the effect of calcination temperature on stability was small except for the bimetallic Co-Ru catalyst which showed different deactivation mechanisms at different calcination temperatures. A higher calcination temperature was generally associated with an increased coking rate due to elevated sintering, while a lower calcination temperature slightly improved the reducibility of the catalysts. Promoting the Ni-Co catalysts with Ru improved their stability and reducibility, but slightly compromised catalyst activity when calcined at high temperature. Coking rate was significantly reduced by Ru addition on the 7.5Ni 7.5Co sample. Excellent stability and the lowest coking rate were achieved at the expense of a slightly lowered activity with the 5Ni 10Co 0.25Ru catalyst calcined at 750 °C.