Ethyl formate hydrogenolysis over Mo2C-based catalysts: Towards low temperature CO and CO2 hydrogenation to methanol

Ester hydrogenolysis is a key step in the production of alcohols and new catalysts are being sought to improve the performance and sustainability of this process. Research described in this paper investigated the use of Cu, Mo2C, and Mo2N-based catalysts for the hydrogenolysis of ethyl formate at 105-150 degrees C and 30 bar H-2. The high surface area Mo2C-based catalysts were more active and selective to methanol than the Mo2N-based catalysts. The deposition of nanoscale Cu and/or Pd particles onto the Mo2C or Mo2N resulted in significant enhancements in the methanol selectivities. The methanol selectivities varied with the acidity or basicity of the support suggesting some degree of cooperation between the Cu or Pd particles and the support. Temporal variations in rates for the Cu/Mo2C catalyst were consistent with first order kinetics with regard to ethyl formate and the activation energy was 44 kJ/mol. The best performance was achieved over a Pd-Cu/Mo2C catalyst; this material outperformed, by a significant margin, the oxide supported Cu catalysts. Given their high activities and selectivities, the Mo2C supported catalysts are attractive candidates for ester hydrogenolysis, including the intermediate step during the low temperature, cascade hydrogenation of CO and CO2 to methanol. (C) 2015 Elsevier B.V. All rights reserved.