Solid state synthesis of Ru-MC with highly dispersed semi-embedded ruthenium nanoparticles in a porous carbon framework for benzoic acid hydrogenation

A mesoporous ruthenium containing carbon Ru-MC-g catalyst with a semi-embedded uniform Ru particle distribution was synthesized by using a dry grinding method using nano-silica as a hard template. The structure and catalytic performance of the embedded Ru-MC-g catalysts were compared with those of the Ru-MC-i catalyst prepared via a wet impregnation method and the carbon supported Ru catalyst (Ru/MC). Among all the obtained catalysts, the Ru-MC-g catalyst prepared by the dry-grinding process shows excellent hydrogenation catalytic activity performance for the chemoselective hydrogenation of benzoic acid to cyclohexane carboxylic acid. The turnover frequency of the Ru-MC catalyst reaches ca. 2400 h(-1) at 4 MPa, 120 degrees C, which is a 6 times improvement compared with that of supported Ru/MC catalyst. The dry-grinding process is expected to be easily scaled up for large-scale production of Ru-based catalysts.