CATALYTIC BEHAVIOR OF OXIDATIVE COUPLING OF METHANE OVER SOLID-SOLUTION (BI2O3)(0.8)(LA2O3)(0.2) IRRADIATED BY MICROWAVE

The catalytic behaviour of oxidative coupling of methane over solid so lution (Bi2O3)(0.8)(La2O3)(0.2) under microwave irradiation was invest igated. Compared with the classical method , the application of microw ave irradiation appears to have beneficial effects: (1) When methane c onversion reaches the same level, under microwave irradiation, the tem perature of catalytic bed is much lower than conventional heating mode . We propose that this is due to ''microwave hot spot effect'' which g enerated by localized coupling of microwave energy to point defects or weak-bond surface, and the ''microwave hot spots'' are just the activ e centers for the production of methyl radicals. (2) Under microwave i rradiation, CO2 can be suppressed to some extent at lower methane conv ersion level, while CO can be suppressed to some extent at higher meth ane conversion level. (3) Under microwave irradiation, the ratio of C2 H4/C2H6 was lower, while C-2-selectivity was higher.