Hydrogenolysis of 1,2‐Propanediol for the Production of Biopropanols from Glycerol

Abstract

Production of propanols from glycerol, which are known as biopropanols, requires catalysts for the hydrogenolysis of 1,2‐propanediol, which has been easily derived from glycerol. It is found that the Rh/SiO₂ catalysts modified with ReO_xspecies exhibited high activity and selectivity in the hydrogenolysis of 1,2‐propanediol to propanols with low selectivity to degradation products and high stability. The optimized RhReO_x/SiO₂ (Re/Rh=0.5) catalyst gave high yields of 1‐propanol (66 %) and propanols (1‐propanol +2‐propanol) (85 %) in the hydrogenolysis of 1,2‐propanediol. In addition, the catalyst was applicable to the one‐pot conversion of glycerol to propanols. The structure of Rh metal particles with attached ReO_xclusters is suggested from the catalyst characterization. It is proposed that 1,2‐propanediol hydrogenolysis proceeds by the hydrogenolysis of the alkoxide species on Re with hydrogen species on the Rh metal surface.