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在固定床反应器上，评价了不同温度下钙钛矿型复合氧化物ＳｒＴｉＯ３和ＣａＴｉＯ３的组成变化对甲烷氧化偶联反应的影响．同时，利用ＸＰＳ和ＣＯ２－ＴＰＤ对催化剂的结构及其氧物种的反应特性进行了表征．结果表明：ＳｒＴｉＯ３和少量Ｃａ掺杂的ＣａｘＳｒｌ－ｘＴｉＯ３有利于在较低温度（９２３Ｋ）下催化反应的活性和选择性，而ＣａＴｉＯ３体系则在高温（１０７３Ｋ）下表现出较好的活性和选择性．钙钛矿型复合氧化物ＳｒＴｉＯ３和ＣａＴｉＯ３组成变化对不同温度下反应活性的影响与ＣＯ２－ＴＰＤ的脱附谱图有很好的平行关系．
The effects of the composition of perovskite-type oxides SrTiO3 and CaTiO3 on the oxidative coupling of methane were evaluated on a fixed-bed reactor. At the same time, XPS and CO2-TPD were used to characterize the structure of the catalyst and the reaction characteristics of its oxygen species. The results show that SrTiO3 and a small amount of Ca-doped CaxSrl-xTiO3 are favorable for the catalytic activity and selectivity at lower temperature (923K), while CaTiO3 shows better activity and selectivity at high temperature (1073K) . The effect of the composition of perovskite-type composite oxides SrTiO3 and CaTiO3 on the reactivity at different temperatures has a good parallel relationship with the desorption spectra of CO2-TPD.