Replacing Precious Metals with Carbide Catalysts for Hydrogenation Reactions

Molybdenum carbide (Mo2C and Ni/Mo2C) catalysts were compared with Pd/SiO2 for the hydrogenation of several diene molecules, 1,3-butadiene, 1,3- and 1,4-cyclohexadiene (CHD). Compared to Pd/SiO2, Mo2C showed similar hydrogenation rate for 1,3-butadiene and 1,3-CHD and even higher rate for 1,4-CHD, but with significant deactivation rate for 1,3-CHD hydrogenation. However, the hydrogenation activity of Mo2C could be completely regenerated by H-2 treatment at 723 K for the three molecules. The Ni modified Mo2C catalysts retained similar activity for 1,3-butadiene hydrogenation with significantly enhanced selectivity for 1-butene production. The 1-butene selectivity increased with increasing Ni loading below 15 %. Among the Ni modified Mo2C catalysts, 8.6 % Ni/Mo2C showed the highest selectivity to 1-butene, which was even higher selectivity than that over Pd/SiO2. Compared to Pd/SiO2, both Mo2C and Ni/Mo2C showed combined advantages in hydrogenation activity and catalyst cost reduction, demonstrating the potential to use less expensive carbide catalysts to replace precious metals for hydrogenation reactions.