Preparation of Zeolite Film on the Surface of Ceramic Filter and Its Application to Reaction/Separation System

沸石是铝硅酸盐的结晶，具有微孔，其大小几乎与碳氢化合物分子相当。这种孔径大小反映了沸石的高形状选择性。然而，这些沸石通常制备为0.1-3毫米大小的粉状晶体。因此，本工作的主要目的是发展制备沸石薄膜的方法，并将所获得的薄膜应用于反应和分离发生在同一位置的系统中。从实验中我们得到了以下结果：1。两种沸石的薄膜；采用本发明的方法在氧化铝陶瓷过滤器表面制备了a型沸石和ZSM-5型沸石。化学气相沉积完全消除了与硅酸铝非晶相相对应的微孔。而对于a型沸石膜，则很难消除宏观孔隙，宏观孔隙对应于沸石晶体之间的孔径。ZSM-5沸石生长膜中几乎没有宏观孔隙。在甲苯-乙醇体系中，利用制备的ZSM-5沸石膜，采用渗透汽化技术实现了乙醇的分离系数约为100。

Zeolites are crystals of alumino-silicate, and have micro pores, the size of which are almost equal to those of hydrocarbon molecules. This pore size reflects on the high shape selectivity of zeolites. However, these zeolites are usually prepared as powdery crystals of 0.1-3 mm in size. Hence, the main objective of this work is to develop the method for preparing zeolites as thin films, and apply the obtained film to the system where the reaction and separation occur at the same position. From experiments we got the following results :1. The thin films of two kinds of zeolites ; A-type zeolite and ZSM-5 zeolite, were prepared on the surface of alumina ceramic filter by the methods developed by us.2. Micro pores, which correspond to amorphous phase of alumino-silicate, were completely eliminated by the technique of chemical vapor deposition. In case of A-type zeolite film, it was, however, difficult to eliminate macro pores, which correspond to the apertures among zeolite crystals. There were to any macro pores of as-grown ZSM-5 zeolite film.3. In the system of toluene-ethanol, the separation factor of ethanol of about 100 was achieved by the pervaporation technique using prepared the ZSM-5 zeolite film.