KAUST-8膜的制备及其对乙醇/水体系的渗透汽化分离性能的研究

Preparation of KAUST-8 membrane and its pervaporation separation performance for ethanol/water system

为实现乙醇作为燃料的高效利用,采用二次生长法制备出亲水性KAUST-8膜并将其对乙醇水溶液进行渗透汽化分离研究。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、比表面及孔隙度分析仪(BET)和热重等分析手段对KAUST-8晶体和膜材料的形貌、结构和性能进行表征,考察了不同操作温度和进料质量分数下,KAUST-8膜对乙醇水溶液分离效果的影响。结果表明,升高渗透汽化的操作温度,总渗透通量从281.44 g/(m^(2)·h)增加至929.16 g/(m^(2)·h),分离因子从17.2降低至6.1。在同一渗透汽化温度(25℃)下,增大进料液中水的质量分数,水通量从124.2 g/(m^(2)·h)增加到302 g/(m^(2)·h),总通量逐渐升高至359.2 g/(m^(2)·h),分离因子逐步从17.2提高至30.2。

In order to realize the efficient utilization of ethanol as fuels,a hydrophilic KAUST-8 membrane is prepared by means of secondary growth method and used for the pervaporation separation of aqueous ethanol solution.The morphology,structure and properties of KAUST crystal and membrane materials are characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),BET and thermogravimetric analysis.The effects of different operation temperatures and feed concentrations on the separation efficiency of KAUST membrane to aqueous ethanol solution are investigated.The results show that total permeation flux increases from 281.44 g/(m^(2)·h)to 929.16 g/(m^(2)·h)and the separation factor decreases from 17.2 to 6.1 when the operating temperature rises.Under the same pervaporation temperature(25℃),water flux increases from 124.2 g/(m^(2)·h)to 302 g/(m^(2)·h),total flux increases to 359.2 g/(m^(2)·h)and the separation factor increases gradually from 17.2 to 30.2 when the water content in the feed solution increases.