Methane Activation by Selective Oxidation

The selective activation of methane by oxidation is a topic that has fascinated scientists and engineers for over a century. In this paper some of the recent approaches will be described and discussed. In particular, the use of FeZSM5 as a catalyst for methane oxidation with aqueous hydrogen peroxide will be described. With this catalyst the primary product is methyl hydroperoxide which decomposes to give methanol. This catalyst is highly active at 50 A degrees C but yields formic acid which is formed by the sequential oxidation of methanol. Addition of Cu either in solution or within the catalyst matrix switches off the sequential oxidation and methanol is obtained with very high selectivity. Comments are made concerning the prospects for the use of molecular oxygen as the terminal oxidant which is the preferred route.