Direct oxidation of methane to methanol over Cu-zeolites at mild conditions

Abstract

The partial oxidation of methane to methanol over a Cu-Na-MOR catalyst is studied in this work. The reaction, performed in a fixed-bed reactor, is accomplished according to a three steps cycling process: adsorption of methane, desorption of methanol promoted by water and regeneration of the catalyst. The operating conditions of the different steps of the process have been optimized to maximize methanol yield. The regeneration using air, instead of pure oxygen, has been found to increase methanol yield in the following cycle. Optimum desorption is carried out using water concentration of 5.2 mol % and 3.04 Nm3 h−1 kg−1cat. At the optimal conditions, the yield of methanol raised to 754 μmol/g Cu, corresponding to 52 % of adsorbed methane being transformed into methanol.