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分别用离子交换法和等体积浸渍法制备了 2 0 %Zn/HZSM 5催化剂 ,并对催化剂中锌组分的不稳定性进行了研究 .高温还原条件下 ,锌由催化剂中缓慢流失 ,而氧化条件下锌组分是稳定的 .锌在氢热处理条件下的流失速率与催化剂的制备方法有关 ,锌组分的稳定性与锌在沸石上的分布及锌物种的状态有关 .将离子交换法制备的Zn/HZSM 5在 5 5 0℃下氢处理 2 0h ,并分别用XRD ,TEM ,XPS以及丙烷芳构化反应评价对其理化性质进行了表征 .结果表明 ,该催化剂保持了沸石阳离子交换位锌物种的存在 ,催化活性基本不变
20% Zn / HZSM 5 catalyst was prepared by ion-exchange method and isostatic-impregnation method, respectively, and the instability of the zinc component in the catalyst was investigated. Under the conditions of high temperature reduction, zinc was slowly lost from the catalyst, Under the conditions of the zinc component is stable.The loss rate of zinc under hydrothermal conditions is related to the preparation of the catalyst, the stability of the zinc component is related to the distribution of zinc on the zeolite and the status of the zinc species.Preparation of the ion exchange method Zn / HZSM 5 at 50 ℃ for 20 h, and the physicochemical properties were characterized by XRD, TEM, XPS and propane aromatization respectively.The results show that the catalyst maintains the zeolite cation exchange site The existence of zinc species, catalytic activity remained unchanged