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考察了用不同来源Ｌｉ（ＬｉＮＯ３和ＬｉＳＯ４）制备的催化剂催化的甲烷氧化偶联（ＯＣＭ）反应的特点，探讨了以ＬｉＮＯ３为锂源制备的催化剂的高温反应失活机理。ＸＲＤ、ＩＲ、ＸＰＳ和ＢＥＴ等方法的研究结果表明，以ＬｉＮＯ３为锂源制备的催化剂具有反应活性高、空速大的特点，而以Ｌｉ２ＳＯ４为锂源制备的催化剂具有Ｃ２选择性高、活性低、空速小等特点。由ＬｉＮＯ３制得的催化剂的失活原因是：在较高的反应温度下由于表面Ｌｉ的流失，使体相晶格中的Ｌｉ向表相扩散进而导致含Ｌｉ活性相ＬａＴｉ１－ｙＬｉｙＯ３－λ的分解（或部分分解），从而减少了体相和表相中氧空位的数量，导致催化剂的活性降低。设计了ＮＨ：（ＳＯ４）２浸渍法来固定表面锂。
The characteristics of the catalysis of methane oxidation coupling (OCM) catalyzed by Li (LiNO3 and LiSO4) from different sources were investigated. The high temperature reaction deactivation mechanism of the catalyst prepared from LiNO3 was discussed. The results of XRD, IR, XPS and BET show that the catalyst prepared with LiNO3 as lithium source has the characteristics of high reactivity and large space velocity. The catalyst prepared with Li2SO4 as lithium source has high C2 selectivity and low activity , Airspeed and other characteristics. The reason for deactivation of the catalyst prepared from LiNO3 is that the diffusion of Li in the bulk phase to the epi-phase due to the loss of surface Li at higher reaction temperatures leads to the decomposition of the Li-containing active phase LaTi1-yLiyO3-λ (Or partially decomposed), thereby reducing the number of oxygen vacancies in the bulk and foregone, leading to a decrease in the activity of the catalyst. NH (SO4) 2 impregnation method was designed to fix the surface lithium.