Effect of amine group on the hydrogenation of aromatic rings over Ru/MgO-Al2O3 catalysts

Ru/MgO-Al2O3 catalysts (2-6 wt% Ru) were prepared by a two-step co-precipitation method and were found to be highly active and selective for the hydrogenation of aromatic amines to alicyclic amines. Hydrogenation of toluene in the presence of triethylamine (TEA) was used as a probe reaction to explain the obtained results. It was found that adsorption of toluene in the presence of TEA on Ru than on Co and Ni catalysts was significantly less inhibited and thus the conversion of toluene. Ru/MgO-Al2O3 was thus found to be significantly superior to the Ni/MgO-Al2O3 and Co/MgO-Al2O3 for the hydrogenation of aromatic amines to alicyclic amines.