Oxidative coupling of methane—A complex surface/gas phase mechanism with strong impact on the reaction engineering

The oxidative coupling of methane over Mn/Na₂WO₄/SiO₂ has been investigated at reaction conditions suitable for industrial applications up to 10 bar in a fixed bed reactor as well as by temporal analysis of products (TAP) by admitting pulses of methane, ethane and ethene oxygen mixtures. The influence of pressure on selectivity is investigated and a concept for optimizing it is derived. A maximum yield is estimated from the ratios of the involved main reactions of the reaction network assuming that the undesired parallel reactions can be suppressed.