Oxidative dehydrodimerization of methane using lead and samarium-based catalysts made by self-propagating high-temperature synthesis

The self-propagating high-temperature synthesis (SHS) method has been used to produce a range of active catalysts based on lead and samarium for the oxidative dehydrodimerization of methane. Catalytic activity was measured at temperatures between 920 and 1120 K under various conditions and various oxides of lead and samarium were found to be active for this process. Ethene yield was found to reach about 20 wt.% (with a selectivity of 88% at a conversion of 24.7%) but the process yielded also significant quantities of ethane, propene, propane and hydrogen. Depending on conditions, methane conversion was found to reach up to 24%. The catalytic activity can be enhanced by varying the synthesis conditions and further treatment after production of the materials. In particular, the porosity needs to be improved substantially.