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Ｌａ２Ｏ３／ＺｎＯ催化剂体系在以二氧化碳作为氧化剂的甲烷氧化偶联反应中具有很高的Ｃ２烃选择性和稳定性．采用ＣＯ２－ＴＰＤ－ＭＳ和ＴＰＲ技术考察了Ｌａ２Ｏ３／ＺｎＯ对ＣＯ２的吸附性质及其氧化还原行为．结果表明：（１）Ｌａ２Ｏ３／ＺｎＯ催化剂体系存在着强、弱两种碱中心，其中弱碱中心数量随样品中Ｌａ２Ｏ３含量增加而减少，强碱中心强度随样品中Ｌａ２Ｏ３含量增加而增强．（２）由于组分相互作用，高温下，Ｌａ２Ｏ３／ＺｎＯ易产生晶格氧空位，使之对ＣＯ２的吸附增强，吸附后的ＣＯ２与晶格氧作用形成立方晶型Ｌａ２Ｏ２ＣＯ３．（３）Ｌａ２Ｏ３／ＺｎＯ表面的Ｌａ３＋和Ｚｎ２＋可以部分被还原，由于组分间的相互作用，使得二者的还原都较单一组分存在时更难．（４）Ｈ２－ＣＯ２－Ｈ２氧化还原循环实验表明，Ｌａ２Ｏ３／ＺｎＯ表面被部分还原后，ＣＯ２可以将部分被还原的表面再氧化．在此基础上对Ｌａ２Ｏ３／ＺｎＯ催化剂上甲烷与ＣＯ２转化为Ｃ２烃的机制也进行了讨论．
La2O3 / ZnO catalyst system has high C2 hydrocarbon selectivity and stability in methane oxidative coupling reaction using carbon dioxide as oxidant. The CO2 adsorption properties and redox behaviors of La2O3 / ZnO were investigated by CO2-TPD-MS and TPR techniques. The results show that: (1) There are strong and weak base centers in La2O3 / ZnO catalyst system. The number of weak base centers decreases with the increase of La2O3 content in the La2O3 / ZnO catalyst system. The intensity of strong base increases with the increase of La2O3 content. (2) Due to the interaction of components, La2O3 / ZnO easily generates lattice oxygen vacancies at elevated temperature, which enhances the adsorption of CO2. The adsorbed CO2 interacts with lattice oxygen to form cubic La2O2CO3. (3) La3 + and Zn2 + on the La2O3 / ZnO surface can be partially reduced, which makes the reduction of the both more difficult than the single component due to the interaction between the components. (4) H2-CO2-H2 redox cycle experiments show that, after partial reduction of La2O3 / ZnO surface, CO2 can re-oxidize some of the reduced surface. On this basis, the mechanism of conversion of methane and CO2 to C2 hydrocarbons on La2O3 / ZnO catalyst was also discussed.