摘要
以工业应用的反渗透(RO)聚酰胺(PA)复合膜为支撑膜,通过组合浸涂法和界面缩聚(IP)法的两步成膜工艺,制备了分离层为交替复合的聚酰胺/聚乙烯醇/聚酰胺(PA/PVA/PA)多层复合膜(MLCM)。用扫描电子显微镜(SEM)和原子力显微镜(AFM)分析了PA/PVA/PAMLCM的结构特征。结果表明,浸涂和IP的工艺条件是影响MLCM的分离性能以及微结构的主要因素。优化工艺制成的PA/PVA/PAMLCM,在实验温度20℃和下游真空度小于1000Pa时,渗透汽化(PV)分离异丙醇(IPA)浓度为87.8%的水混合物,渗透通量(J)为60～80g·m-2·h-1,渗透物中水含量(Cp-H2O)达99%以上。不同材料制成的多层交替复合的分离层具有显著的微结构形态和独特的双重选择性分离功能,其纳米-亚微米级厚度的多层结构强化了复合膜的水渗透性。
With the large-scale industrially manufactured polyamide （PA） as the support layer, PA/PVA/PA, the multilayer composite membrane （MLCM） with alternate separation layers was prepared by two preparation process in succession, dip-coating technique and interfacial polycondensation （IP）. The microstructure characteristic of the prepared PA/PVA/PA MLCM was explored through the micrographs of scanning electron microscope （SEM） and atom force microscope （AFM）. The results show that the technical conditions of the dip-coating process and IP are the critical factors affecting the separation performance and the microstructure characteristic of the prepared PA/PVA/PA MLCM. When using the PA/PVA/PA MLCM prepared under its optimized preparation conditions to separate the isoproponol alcohol （IPA）/water mixture with concentration of 87.8% by pervaporation （PV） at 20℃ and vacuum〈1000 Pa, the permeate flux （3） of 60-80 g·m^-2·h^-1 and the water concentration in the permeate （Cp-H2O） of more than 99% can be achieved. The results show that the multiple separation layer formed by different materials alternately has obvious morphology of microstructure and distinct double-selectivity, and its multiplayer structure with a thickness of nano-submicron level enhances its water permeability.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2009年第6期1030-1037,共8页
Journal of Chemical Engineering of Chinese Universities
基金
浙江省自然科学基金重点重大项目(ZC0204)
浙江省"重中之重"项目"食品科学与工程"学科的资助
关键词
聚酰胺
聚乙烯醇
界面缩聚
膜
交替复合
渗透汽化
polyamide
polyvinyl alcohol
interfacial polycondensation
membrane
composite alternately
pervaporation
