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用ＸＲＤ、ＦＴ－ＩＲ、ＥＳＲ、Ｈ２－ＴＰＲ和ＴＰＯ等方法，对Ｎａ２ＷＯ４－Ｍｎ２Ｏ３／ＳｉＯ２催化剂和其经水煮处理的一系列样品进行了表征．实验发现该催化剂中的结晶态Ｎａ２ＷＯ４易于流失，单层分布的Ｎａ２ＷＯ４在苛刻的处理条件下也有可能流失．依此，探讨了上述流失现象与Ｎａ２ＷＯ４－Ｍｎ２Ｏ３／ＳｉＯ２催化剂的催化活性及该催化剂在长时间反应中发生的ＳｉＯ２相变之间的关系，证明了结晶态Ｎａ２ＷＯ４的流失对该催化剂甲烷氧化偶联反应的催化活性只有轻微的影响，单层分布Ｎａ２ＷＯ４的流失可造成催化剂中Ｍｎ从Ｍｎ３＋转变为Ｍｎ２＋，并使催化剂的催化活性明显降低．但在水煮条件下，无论是结晶态的还是单层分布，Ｎａ２ＷＯ４的流失都没有对ＳｉＯ２的α－方石英结构产生影响
A series of Na2WO4-Mn2O3 / SiO2 catalysts and their pooled samples were characterized by XRD, FT-IR, ESR, H2-TPR and TPO methods. It is found that the crystalline Na2WO4 in the catalyst is easily lost and the monolayer Na2WO4 is also likely to be lost under harsh treatment conditions. Based on this, the relationship between the above-mentioned loss phenomenon and the catalytic activity of Na2WO4-Mn2O3 / SiO2 catalyst and the phase transition of SiO2 occurring in the reaction over a long period of time was investigated, and it was proved that the loss of crystalline Na2WO4 to the catalyst was oxidatively coupled The catalytic activity of the reaction has only a slight effect. The loss of monolayer Na2WO4 can cause the Mn in the catalyst to change from Mn3 + to Mn2 +, and the catalytic activity of the catalyst is obviously reduced. However, under boiling conditions, both the crystalline state and the monolayer distribution, the loss of Na2WO4 did not affect the α-cubic quartz structure of SiO2