Interaction between nickel and molybdenum in Ni–Mo/Al2O3 catalysts: III.: Effect of impregnation strategy Original Research Article

Bimetallic 5 wt.% Ni-5 wt.% Mo/Al2O3 catalysts prepared by sequential impregnation and coimpregnation were tested for their physical properties, activity, and selectivity characteristics in COx hydrogenation at 523–598 K using different feed compositions. Experimental results show that the coimpregnated Ni–Mo catalyst has the highest active metal surface area. Specific activities and activation energies for CO2 methanation on coimpregnated and sequentially impregnated catalysts indicate that the nature of the synergetic interaction is not affected by the impregnation sequence. CO hydrogenation at relatively high C/H ratios and temperatures above 548 K is accompanied by activity losses on all samples due to carbon deposition. Although there is no significant relation between carbon deposition and C2–C4 selectivities, a positive effect on olefin to paraffin ratios is observed at intermediate temperatures.