METHANE OXIDATION USING AU MGO CATALYSTS

A series of Au/MgO (0.04-15 wt%) catalysts have been investigated for the oxidation of methane. Detailed electron microscopy and Mossbauer s pectroscopy studies show that two distinct Au morphologies can be obse rved: (a) two-dimensional Au rafts and (b) discrete three-dimensional An particles (5-10 nm in diameter). The two-dimensional rafts are obse rved as the main form of Au at low loadings and, interestingly, these are observed to poison the methane coupling activity of MgO. As the Au loading is increased the proportion of Au present as discrete particl es increases and these are considered to be active for methane oxidati on to CO and CO2.