Power-law kinetics of methanol synthesis from carbon dioxide and hydrogen on copper-zinc oxide catalysts with alumina or zirconia supports

Kinetics of methanol synthesis from carbon dioxide and hydrogen were studied on two catalysts, a copper-zinc oxide-alumina catalyst (CuZA) and a copper-zinc oxide-zirconia (CuZZ) catalyst. Although both catalysts show similar turnover frequencies for the methanol synthesis reaction, CuZZ is more selective for methanol synthesis because the reverse water gas shift reaction occurs more slowly on this catalyst. The results of the catalytic tests were modeled with power-law equations which highlight the strong positive impact of hydrogen partial pressure on methanol synthesis activity and selectivity. The comparison of the experimental results with thermodynamic equilibrium allows separating thermodynamic and kinetic driving forces. (C) 2015 Elsevier B.V. All rights reserved.