A series of Mo(5)/H-MCM-22 catalysts with various Si/Al₂ ratios were applied to methane dehydroaromatization reaction. According to the NH₃ TPD, XPS, TPO, UV Raman and STEM-EDS analysis, it is clearly verified that Brønsted acid site, determined by the Si/Al₂ ratios, stabilizes monomeric Mo oxide species, by facilitating to migrate Mo oxides into the microchannel of zeolite, so that it can influence the distribution of catalytically active Mo oxide species. Combined TPO and UV Raman analysis of post-reaction catalysts obviously confirmed that HT (high temperature) type coke is primarily composed of polyaromatics such as naphthalene and anthracene, which brings about the deactivation of the catalyst during MDA reaction. The formation of HT type coke is mainly affected by the amount of Mo oxides present on the external surface of zeolite, which indicates that the major role of zeolite microchannel is to provide a shape-selective environment during the conversion of methane to benzene. To sum up, an increment in Brønsted acid site enhances the dispersion of Mo oxides, thus leading to the improved methane conversion rate and benzene formation rate while suppressing the formation of HT type coke concomitantly.

将一系列具有各种Si / Al ₂比的Mo（5）/ H-MCM-22催化剂应用于甲烷脱氢芳构化反应。根据NH ₃ TPD，XPS，TPO，UV拉曼和STEM-EDS分析，可以清楚地证明由Si / Al ₂确定的布朗斯台德酸位通过促进Mo氧化物向沸石的微通道中的迁移，可以稳定单体Mo氧化物的种类，从而可以影响催化活性Mo氧化物的分布。对反应后催化剂的TPO和UV拉曼分析相结合，显然证实HT（高温）型焦主要由诸如萘和蒽等多芳烃组成，从而使MDA反应期间的催化剂失活。HT型焦炭的形成主要受沸石外表面上存在的Mo氧化物含量的影响，这表明沸石微通道的主要作用是在甲烷转化为苯的过程中提供形状选择环境。综上所述，布朗斯台德酸位点的增加会增强Mo氧化物的分散性，