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本文研究了５种不同制法的Ｌａ＿２Ｏ＿３对甲烷氧化偶联的催化性能，其Ｃ＿２选择性和Ｃ＿２收率的相对顺序为：Ｌａ＿２Ｏ＿３（１）＞Ｌａ＿２Ｏ＿３（２）＞Ｌａ＿２Ｏ＿３（４）＞Ｌａ＿２Ｏ＿３（５）＞Ｌａ＿２Ｏ＿３（３）。并运用ＸＲＵ、ＸＰＳ、ＣＯ＿２－ＴＰＤ、ＮＨ＿３－ＴＰＤ和ＩＰＡ转化反应等技术分别对催化剂的体相结构和表面性质，表面酸碱性进行了测定。结果表明，由于制备方法的不同，导致了Ｌａ＿２Ｏ＿３晶体表面结构的差异，这是影响催化性能的主要原因。同时还发现，催化剂的活性和Ｃ＿２选择性与表面酸碱性存在着相依性，Ｌａ＿２Ｏ＿３表面的总碱位数与总酸位数的比值，与其催化性能有较好的直接对应关系。
In this paper, the catalytic performance of La 2 O 3 on methane oxidative coupling was studied. The relative order of C 2 selectivity and C 2 yield was: La 2 O 3 (1)> La 2 O 3 (2)> La 2 O 3 (4)> La 2 O 3 )> La 2 O 3 (3). XRD, XPS, CO_2-TPD, NH_3-TPD and IPA conversion reactions were used to determine the phase structure, surface properties and surface acidity of the catalysts respectively. The results show that due to the different preparation methods, the crystal structure of La 2 O 3 crystal is different, which is the main reason that affects the catalytic performance. At the same time, it was also found that the activity of catalyst and selectivity of C_2 were dependent on the surface acidity and basicity. The ratio of the total alkaloids on the surface of La_2O_3 to the total acid sites had a good direct relationship with the catalytic performance.