Low Temperature Methanol Synthesis from CO Hydrogenation Over Cu-Based Catalyst

Abstract: A novel liquid phase methanol synthesis process from syngas was realized by combination catalyst system of Cu-based catalyst and alkali formate, high CO conversion(>80%) as well as methanol selectivity (~90%) was achieved with a mass space velocity of 1800L/h.kg-cat. at 433K and 5.0 MPa via ethyl formate in slurry phase. Experimental results revealed that synergic function between formate species and solid copper catalyst, which made a new active site, contributed to the high catalytic performance in the presence of alcohol solvent. During the reaction, formate species was found to work together with carbonate, bicarbonate and hydroxide against dynamic equilibrium in liquid phase, among which formate was assumed to be the active species. In addition, carbonylation of alcohol to alkyl formate acted as the limiting rate step in the occasion where blocking effect of alkali group played a minor role.

Keywords: methanol synthesis, CO hydrogenation, formate, slurry phase, low temperature