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Two series of Sr-Pb-O and Sr-Pb-O/γ-Al_2O_3 catalysts of differentcomposition were investigated for the oxidative coupling of methane.Theeffects of reaction conditions on the catalytic behavior have been studied.Catalyst characterization was carried out by XRD,TPR,TPD and XPS tech-niques.It was found that a strong interaction took place between Sr-Pb-Oand γ-Al_2O_3 so that Sr_3Al_(32)O_(51)phase and a small amount of PbAl_2O_4 formedin the bulk and the surface was mainly enriched with Pb.A 30 wt% Sr-Pb-O/γ-Al_2O_3 catalyst gave a 30.4% methane conversion and a 50% C_2 selec-tivity at 750℃ and with a feed gas composition of CH_4:O_2=2.5:1.Theenrichment of Pb on the surface may be responsible for the higher catalyticactivity and selectivity.