甲烷在含镓沸石(MFI)上无氧活化性能的研究

Non oxidative Activation of Methane over Ga Containing Zeolites

采用水热法合成了不同Ｓｉ／Ａｌ、Ｓｉ／Ｇａ比的含镓分子筛．催化反应活性表征结果表明，对丙烷芳构化反应具有良好催化活性的含镓分子筛，没有显示出任何催化甲烷芳构化反应的特性；ＭｏＯ３作为添加组分显著地改变了催化剂的反应性能．３％ＭｏＯ３负载的含Ｇａ分子筛（Ｓｉ∶Ａｌ∶Ｇａ＝５０∶２∶１），在９７３Ｋ温度条件下给出了约６％甲烷转化率和大于８０％的芳烃选择性．与ＺＳＭ－５相比，在相同的ＭｏＯ３担载条件下，含Ｇａ分子筛催化剂甲烷芳构化活性较低，但是镓的引入提高了乙烯的选择性．

The H Galloaluminosilicate (MFI) and H Gallosilicate (MFI) with various Si/Al,Si/Ga ratios have been synthesized by hydrothermal method. The influence of zeolites, with and without loading MoO 3,on the catalytic performance of methane non oxidazing aromatization has been investigated. The results show that zeolites containing Ga species, which were found to be excellent catalysts for propane aromatization, are not suitable for methane aromatization. The addition of second component MoO 3 is a crucial factor for this reaction; without adding MoO 3, formation of benzene can not been observed at 973 K. H Galoalluminosilicate with 3% MoO 3 loading has methane conversion of 6% and benzene selectivity more than 80% as compared with H ZSM5 of the same Mo loading, the catalysts containing Ga species have lower methane conversion but higher ethene selectivity. Activation of methane and propane may take different routes judging from the experimental results of this.