The Direct Partial Oxidation of Methane to Dimethyl Ether over Pt/Y2O3Catalysts Using an NO/O2Shuttle

Using a mixture of NO + O(2)as the oxidant enabled the direct selective oxidation of methane to dimethyl ether (DME) over Pt/Y2O3. The reaction was carried out in a fixed bed reactor at 0.1 MPa over a temperature range of 275-375 degrees C. During the activity tests, the only carbon-containing products were DME and CO2. The DME productivity (mu mol g(cat)(-1) h(-1)) was comparable to oxygenate productivities reported in the literature for strong oxidants (N2O, H2O2, O-3). The NO + O(2)mixture formed NO2, which acted as the oxygen atom carrier for the ultimate oxidant O-2. During the methane partial oxidation reaction, NO and NO(2)were not reduced to N-2. In situ FTIR showed the formation of surface nitrate species, which are considered to be key intermediate species for the selective oxidation.