湿凝胶转化制备NaA沸石膜及应用研究

Preparation of NaA zeolite membrane by wet gel transformation and its application

选用3~4μm的沸石晶体作为大晶种配制悬浮液,将原有沸石大晶体进行球磨后得到尺寸约200 nm的晶体作为小晶种配制悬浮液,通过湿凝胶转化法制备NaA型膜。利用XRD、SEM对膜层的结构与形貌进行表征,并将其用于醇水溶液的分离及性能考察。结果表明,在373 K的温度下晶化反应4 h,NaA沸石膜交互生长性较好,膜层致密较薄、性能优异。工业化放大应用中便于操作,较平板型载体有更好的应用价值。

A suspension is prepared by using the purchased 3-4μm zeolite crystal as the large crystal seed,and the 200 nm zeolite crystal,which is obtained by ball milling the original zeolite crystal,as the small crystal seed.NaA membrane is prepared via wet gel transformation method.XRD is employed to analyze the material,and SEM is used to characterize the structure and morphology of the membrane.The membrane is used to separate alcohol aqueous solution in order to investigate its properties.According to experimental results,NaA zeolite membrane has good interactive growth with dense and thin film after crystallization reaction has performed at 373 K for 4h.The subsequent performance test of NaA zeolite membrane in long-term alcohol system proves that it has excellent performance and is easy to operate in industrial scale-up application,and has better application value than flat carrier.