Highly loaded and dispersed cobalt catalysts for the hydrogenation of toluene with triethylamine

Highly dispersed and loaded (60%wt) catalysts Co/MgAlO, Co/MgO and Co/Al2O3 were prepared for the hydrogenation of toluene without and with triethylamine (TEA). It was found that while Al2O3 favored the dispersion of Co, MgO promoted the reduction of CoOx so that the Co/MgAlO exhibited the small Co particles (~6.5 nm), high H2 uptake (363 μmol/g) and thus was highly active for the hydrogenation reaction without TEA (not only higher than the Co/Al2O3 and Co/MgO, but also higher than the 60%Ni/MgAlO). In addition, the adsorption heat of TEA was significantly lower on the Co/MgAlO than on the Ni/MgAlO so that the reaction activity for the hydrogenation of toluene was significantly less affected by TEA on the Co/MgAlO than on the Ni/MgAlO. Thus, the Co/MgAlO can be expected to be better than the Ni/MgAlO for the synthesis of alicyclic amines from aromatic amines.