【摘要】 在甲烷氧化偶联（OCM）反应条件下，用原位红外光谱研究SrO-La2O3／CaO催化剂，结果表明，晶格氧使甲烷深度氧化La2O3和CaO具有活泼的晶格氧，SrO的晶格氧比较稳定，气相氧通过补充催化剂表面消耗掉的晶格氧，加速了甲烷的深度氧化．另一方面，催化剂表面的碳酸根物种在氧气氛下分解.在La2O3和LC催化剂中，催化剂表面La2O2（CO3）的分解形成配位不饱和的晶格氧O2-，并为气相氧吸附提供氧空穴．气相氧在氧空穴上吸附和配位不饱和晶格氧向吸附氧转移电荷，产生活供氧物种（可能为O2-）．红外光谱能检测到波数为1118cm-1的吸收峰在CaO，SrO和SLC催化剂上，未能用FT－IR检测到类似的活性氧物种，但有C2产物生成，推测表面碳酸根分解可能直接产生活性氧物种（可能为O22-）．更多还原

【Abstract】 SrO-La2O3/CaO(SLC) catalysts have been found to be active for the oxidative coupling of methane (OCM), but the lattice oxygen of them is only active for total okidation as revealed by the studies of in - situ FT-IR on the interaction between CH4 and the oxide surface concerned.The results of an in - situ FT-IR study on the interaction of the milxture of CH4 and O2 with the catalyst surface show that the oxygen in gas phase can accelerate the total okidation of CH4 via replenishing the lattice oxygen consumed on one hand, and on the other hand, it will promote the decomposition of surface carbonates formed during the reaction. For La2O3 and LC catalysts, the decomposition of surface La2O2(CO3) carbonate results in the formation of coordination unsaturated oxygen species and oxygen vacancy, and then the oxygen in gas phase could be adsorbed on the oxygen vacancy and electron tranfer from coordination unsaturated oxygen species to the oxygen adspecies talles place to produce active oxygen species, probably in the form O2-, with the characteristic IR band at 1180cm-1. Meanwhile on the surfaces of CaO, SrO and SLC catalysts, although no any active oxygen species could be detected, the formation of c2H4 product stin is observed at high temperatures. Therefore, it is speculated that the decomposition of sarface carbonates directly leads to the formation of active oxygen species, O2-.更多还原