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催化剂Ｍｏ／ＨＺＳＭ－５在甲烷无氧脱氢芳构化反应中表现出很高的活性．用ＸＲＤ，ＢＥＴ比表面，ＮＨ３－ＴＰＤ及ＴＰＲ等手段，对氨水抽提前后催化剂上的活性Ｍｏ物种进行了研究．ＸＲＤ结果表明，Ｍｏ物种高度分散于分子筛表面．随着Ｍｏ担载量的提高，ＢＥＴ比表面积有所下降；但氨水抽提后，比表面积有很大程度的恢复．ＮＨ３－ＴＰＤ结果表明，Ｍｏ物种优先占据分子筛中的强酸位．ＴＰＲ结果显示出有ＭｏＯ３晶相存在的催化剂较易被还原；但氨水抽提后，基本上无还原峰存在．据此可以认为，分子筛上担载的Ｍｏ物种随担载量的不同，形成了多种不同的结构类型，如单层分散的四配位和六配位结构，ＭｏＯ３微晶以及Ａｌ２（ＭｏＯ４）３晶体等．其中ＭｏＯ３微晶与分子筛的结合力较弱，可被氨水抽提，它可能是甲烷无氧脱氢芳构化反应的主要活性物种．
The catalyst Mo / HZSM-5 showed high activity in the anaerobic dehydroaromatization of methane. The active Mo species on the catalyst before and after ammonia water extraction were studied by means of XRD, BET surface area, NH3-TPD and TPR. XRD results show that Mo species are highly dispersed on the surface of molecular sieves. With the increase of Mo loading, the BET specific surface area decreased; however, the specific surface area recovered to a great extent after ammonia water extraction. The NH3-TPD results show that the Mo species preferentially occupy the strong acid sites in the molecular sieve. The TPR results show that the catalyst with MoO3 crystal phase is easier to be reduced; however, there is almost no reduction peak after ammonia water extraction. Based on this, it can be concluded that Mo species supported on molecular sieves have different structures with different loadings, such as monolayer disordered tetracoordinate and hexacoordinated structures, MoO3 crystallites and Al2 (MoO4) 3 crystals and so on. Among them MoO3 crystallites and molecular sieve bond strength is weak, it can be ammonia water extraction, it may be methane anaerobic dehydroaromatization reaction of the main active species.