Decomposition processes of the mixed-template, tetraethylammonium hydroxide (TEAOH) and tetramethylammonium chloride (TMAC1), in UZM-5 zeolite under inert atmosphere or oxygenous atmosphere were studied by means of TG-MS, and the decomposition products were characterized by means of XRD. The results indicated that TMAC1 in UZM-5 zeolite existed in the two forms of TMAC1 and TMA+. With the rise of temperature, firstly, TMA+ outside of the molecular sieve pore canals degraded, then TMA + inside of the pore canals and TMAC1 degraded, and finally, TEA+ inside of the pore canals began to degrade, which led to collapse of the molecular sieve skeleton and escape of the gaseous reaction products. Under the oxygenous atmosphere, the oxidation and the decomposition of the templates happened simultaneously, and the quantity of heat released under the oxygenous atmosphere was 4.4 times that released under the inert atmosphere. A lot of heat liberation in the reaction is a main reason for the change of the molecular sieve structure.%采用TG - MS联用的方法,考察了惰性气氛和有氧气氛下UZM -5分子筛中双模板剂四乙基氢氧化铵(TEAOH)-四甲基氯化铵(TMACI)的分解过程,并采用XRD方法表征了试样的结晶度.实验结果表明,TMA+在UZM-5分子筛中以TMA+Z-(Z为分子筛骨架)及TMACl两种方式存在；随温度的升高,孔道外的TMA+先分解,随后TMACI及位于孔道内的TMA+分解,最后位于分子筛孔道内的TEA+分解,分子筛结构坍塌,气体产物从坍塌的骨架处逸出；在有氧气氛下,模板剂的氧化反应和分解反应同时进行,释放的热量为惰性气氛下的4.4倍,大量的热量是导致分子筛结构坍塌的主要原因.
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