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合成了晶粒大小、外观形貌、颗粒表面光滑程度以及聚集状态等微织构均不相同的三种沸石分子筛。其中颗粒细小而均匀,呈长条状的分子筛C,经离子交换后与其余两者相比具有较高的Si/Al 比、较低的总酸量及强酸百分比,原粉Na_2O 含量甚低,甚至可以省略离子交换步骤。由于分子筛C 的筒形及Z 字形两组孔道较短及粒子间形成的缝隙多,有利于反应物与生成物的扩散,故提高了催化剂的利用率,在用于甲醇转化制取烃类的反应中,结炭速率低、失活慢、活性稳定性良好,在1000小时寿命试验中仅再生三次;而分子筛B 制成的催化剂则需经历七次再生。但是,从每次再生后油相产品中芳烃的含量变化来推测,分子筛B 自身的结构则更为稳定,虽经多次再生,其酸性也相当稳定。
Three kinds of zeolite molecular sieves with different micro-texture, such as grain size, appearance and appearance, grain surface smoothness and aggregation state, were synthesized. Among them, fine and uniform particles with long stripe shape molecular sieve C had higher Si / Al ratio, lower total acidity and strong acid percentage after ion exchange, lower content of Na 2 O in raw powder, The ion exchange step can even be omitted. As the molecular sieve C cylindrical and zigzag two short channels and the formation of the gap between the particles is conducive to the proliferation of reactants and products, it improves the utilization of the catalyst, used in the conversion of methanol to produce hydrocarbons In the reaction, the rate of carbon formation was low, the activity was slow, and the activity was stable. Only three regenerations were carried out in the 1000-hour life test, while the catalyst prepared by molecular sieve B had to undergo seven regenerations. However, from the change of the content of aromatics in the oil products after each regeneration, it is presumed that the structure of the molecular sieve B itself is more stable, and its acidity is quite stable even after repeated regeneration.