原位水热合成b轴Silicalite-1膜时间控制及乙醇-水物系分离

Timing Control on b-Oriented Silicalite-1 Synthesized by In-Situ Hydrothermal and Separation of System of Ethanol and Water

以石英载玻片为基质,正硅酸乙酯为硅源,四丙基氢氧化铵为模板剂,对比研究在动态和静态环境下通过原位水热合成法合成Silicalite-1膜的生长行为及乙醇-水混合物的分离性能.采用扫描电子显微镜(SEM)、X射线衍射(XRD)和傅立叶红外光谱(FT-IR)对膜层形貌、厚度和晶形进行表征.结果表明:静态水热环境比动态水热更有利于b轴取向Silicalite-1膜的定向生长,在水热温度170℃,水热时间为3h时,获得了致密覆盖、结构有序、高度b轴取向排列的Silicalite-1膜层;动态水热合成Silicalite-1膜速率快、膜层厚度均匀,晶面呈随机取向.通过渗透汽化实验在60℃分离5wt.%乙醇/水溶液,动态和静态水热合成Silicalite-1膜的渗透通量分别为1.52kg·m^(-2)·h^(-1)和3.01kg·m^(-2)·h^(-1),分离因子分别为3.14和2.35.

The growth behavior of Silicalite-1 membrane synthesized by in-situ hydrothermal by using quartz glass slide as matrix, tetraethyl orthosilicate as silica source and tetrapropylammonium hydroxide as templating agent and separation performance of mixture of ethanol and water were studied compara- tively under dynamic and static conditions. Scanning electron microscopy （SEM）, X ray diffraction （XRD） and Fourier transform infrared spectroscopy （FT-IR） were used to characterize the morphology, thickness and crystal morphology of the films. The results show that the static hydrothermal environ- ment is more conducive to the growth of b-oriented Silicalite-1 film than dynamic hydrothermal, Sili- calite-1 film with the advantages of dense cover, ordered structure and highly b-oriented aligned are ob- tained under the hydrothermal temperature of 170 ~C and the hydrothermal time of 3 hours; The method of dynamic hydrothermal synthesis of Silicalite-1 film has some advantages, such as quick speed, uni- form film thickness and the crystal surface oriented randomly. The results of pervaporation experiment carried in the temperature of 60 degrees and 5 wt. % ethanol/water solution and the permeate fluxes were 1.52 kg · m-2·~ h -1 and 3.01 kg · m -2 . h-1 of Silicalite-1 film synthesized by hydrothermal under dynamic and static conditions,and the separation factor （a） of ethanol were 3. 14 and 2. 35, respectively.