Abstract: The oxidative coupling of methane was studied over the Li-Ni-La-Omixed oxide cata-lysts.The effects of the catalyst composition and the reaction conditions on the activited of catalysts were examined.Ahigher C₂ yield of 25.8% was obtained at 780℃ and 15000 h^-1.The surface and bulk structures of the catalysts were characterized by means of XRD, IR, XPS, SEM.The results clearly indicate that in the series of catalysts LiLa_1-xNi_xO₂, when 0.1≤ x≤0.95 the catalyst was composed of two phases La₂Ni_{1-yLiyO4-λ and LiNiO2 When x<0.3, LiLaO2 phase appeared.Among them La2Ni1-yLiyO4X possessed much higher catalytic activity for methane-oxidative coupling.The increase of the content of active site Li⁺-O^--Ni²⁺ was the main factor for increasing the catalytic activity of methane-oxidative coupling.The synergeatic effect of different phases in the catalysts is also supposed.}

Key words: Methane, Oxidative coupling, Lithium-nickel-lanthanum oxide (Ed.: Y, X)