影响渗透汽化中空纤维复合膜分离性能的制备工艺研究

RESEARCHES ON EFFECT OF PREPARATION PROCESS OF HOLLOW FIBER COMPOSITE MEMBRANE ON SEPARATION PERFORMANCE FOR PERVAPORATION

采用聚乙烯醇 (PVA)为分离层的膜材料 ,以浸涂工艺把 PVA复合到聚砜 (PS)或聚丙烯腈 (PAN)的中空纤维支撑层上 ,在长度为 0 .4m的不锈钢管中组装若干根中空纤维复合膜 ,测定对乙醇水溶液的渗透汽化 (PV)分离性能。结果表明 ,PVA/PAN中空纤维复合膜的性能优于 PVA/PS,内径较大 (1 .3mm)的优于内径较小 (0 .4mm)者 ,PVA水溶液在中空纤维支撑层上的涂复次数对复合膜 PV分离性能、以及 PVA/PAN复合膜热处理交联过程对中空纤维的尺寸都会产生明显影响。组件的中空纤维复合膜长度和内径比不同 ,膜的下游压力高低不同 ,导致

Polyvinyl alcohol (PVA) as a membrane material of the separation layer was composited on polysulfone(PS) or polyacrylonitrile(PAN) hollow fiber as a supporting layer by dip coating process. The composite membranes were assembled in a stainless steel tube with the length of 0.4m,and the separation performance of the composite membrane for an aqueous alcohol was determined by pervaporation. The results shown that the separation performance of PVA/PAN is superior to that of PVA/PS, and that of the bigger interior radius is better than that of the smaller radius for the hollow fiber composite membrane. The dip coating times of the hollow fiber support in the PVA solution,and the crossing process of the PVA/PAN composite membrane obviously affected the separation performance of the composite membrane and the poresize variation of hollow fiber membrane in the course of heat treatment.The differences of ratio of length to interior radius of the oomposite membrane and the pressure on the down stream of the membrane have obviosly intluence on the PV separation performane.