A Comparison of the Behaviours at Short Residence Times for the Oxidative Coupling of Methane of Ba/CaO Catalysts with Those of Li/MgO, Sm₂O₃ and La₂O₃ Catalysts

This paper gives a comparison of initial rate data, obtained at relatively low temperatures, for a number of different catalyst systems which are active and selective for the oxidative coupling of methane: Ba/CaO, Li/MgO, the cubic and monoclinic forms of Sm₂O₃, and La₂O₃. It is shown that the Li/MgO system gives much higher initial selectivities than those observed with the other systems. The reaction network for the oxidative coupling reaction is discussed in relation to the results for the different systems and possible mechanistic conclusions are advanced. Finally, some suggestions are made concerning the consequences of these ideas in relation to possible future improvements in catalyst design and process operation.