SELECTING OXYGEN SOURCE FOR PARTIAL OXIDATION OF METHANE TO METHANOL USING MICROWAVE PLASMAS

The methanol selectivity in partial oxidation of methane in microwave plasma reactors is improved by using H2O in the presence or absence of O-2. The use of H2O2 as an oxygen source has a similar effect, although it is less effective than H2O. The addition of H-2 to the system has little effect on selectivity. Two pathways are suggested for the formation of methanol. One involves a CH3O. or CH3O2. intermediate, while the other involves a direct combination of CH3. and OH. radicals. The first pathway is favored in the presence of O-2 while the latter is favored in the presence of H2O or H2O2. The best results are obtained for the CH4-O-2-H2O system when methanol is formed through both pathways.