Development of Catalytic Zeolite Membrane and Its Application to Simultaneous Resction and Separation

沸石是一种结晶铝硅酸盐，广泛用作催化剂和吸附剂。MFI型沸石在其晶体内具有细孔，其直径几乎与苯的分子大小相同。因此，沸石显示出高分子筛效应。将沸石成功地制成膜状后，该膜可实现新的分离，实现高性能的反应分离同时进行。本计画的主要目的为开发MFI型沸石触媒膜，并将其应用于高分离及反应分离同时进行的过程，于1997年度进行了以下研究工作：利用一种新的方法--充分混合的水热合成法，成功地制备出无针孔的MFI型触媒膜。发现该膜显示出高的抗热冲击和机械冲击的能力，并且在高于773 K下使用。 ...更多信息 1998年将该膜应用于高分离和反应分离同时进行的过程中，取得了如下结果：1）从浓醋酸中选择性渗透水;在温度为343 ~ 363 K，醋酸浓度为20 ~ 98%的条件下，只有水可以透过膜.2）从氢气与氮气、氧气和二氧化碳的混合物中选择性分离氢气：在483 K下，在流动系统中发现氢气与另一种气体的分离因子约为100。[）醚（]SY.三取代的左。[）烯烃（]SY.三取代的左。[）石蜡+芳烃。甲醇扩散通过催化沸石膜进行反应。当甲醇转化为烯烃时，它们完全通过膜，从而获得高的烯烃选择性。烯烃的选择性由传统固定床反应器的7%提高到85%。少

Zeolites are crystalline alumino-silicate, and widely used as catalysts and adsorbents. MFI-type zeolite has fine pores within its crystals, the diameter of which is almost the same as the molecular size of benzene. Hence, the zeolite shows high molecular-sieving effect. When the zeolite is succeeded to be prepare in the shape of membrane, the membrane can enable to realize new separation and simultaneous reaction and separation with high performance. The main objective of this project is to development of MFI-type zeolite catalytic membrane, and to apply it to high separation and simultaneous reaction and separation processes.In fiscal year of 1997, we conducted the following research work :MFI-type catalytic membrane was succeeded to prepared without any pin-holes by a new method, well-mixed hydrothermal synthesis. This membrane was found to show high proof against thermal and mechanical shocks and to be used at above 773 K.The separation factor of para- to ortho-isomers of xylene an … More d diethyl-benzene was 3 and 7, respectively.In fiscal year of 1998, the membrane was applied to high separation and simultaneous reaction and separation processes, and the following results were obtained :1) Selective permeation of water from concentrated acetic acid : only water can permeate through the membrane under the conditions of temperature from 343 K to 363 K and the concentration of acetic acid from 20 to 98%.2) Selective separation of hydrogen from mixtures of hydrogen with nitrogen, oxygen and carbon dioxide : the separation factor of hydrogen to the other gas was found to be about 100 in the flow system at 483 K.3) Simultaneous reaction and regeneration : Reaction of methanol is a consecutive reaction, such as methanol (]SY.tri-substituted left.[) ether (]SY.tri-substituted left.[) olefin (]SY.tri-substituted left.[) paraffin+aromatics. Methanol diffuses through the catalytic zeolite membrane undertaking the reaction. When methanol is converted to olefin, they pass completely through the membrane, attaining high selectivity of olefin. The selectivity of olefin was enhanced up to 85% as compared with only 7% for the usage of conventional fixed bed reactors. Less