浸渍提拉法制备TiO2/不锈钢中空纤维复合膜及其应用

Preparation and application of TiO2/stainless steel hollow fiber composite membrane by dip-coating method

大孔无机膜基底的表面改性,一般采用溶胶凝胶法以求表面均匀性.但该法合成工艺复杂,控制因素较多,限制了其在工业领域的应用.利用悬浮液体系改性不锈钢中空纤维膜,采用浸渍提拉法在不锈钢膜表面涂覆25 nm的TiO2粒子,通过500℃的高温烧结制备了TiO2/不锈钢中空纤维复合膜.研究了聚乙烯醇(PVA)和TiO2浓度对不锈钢中空纤维膜的形貌,孔径,纯水通量和抗污染性能的影响.结果表明,所制备的TiO2功能层具有超亲水和水下超疏油性,对BSA的截留率达到90%,油水乳液分离率超过99%,并且具有良好的分离性能和抗污染性能.

The surface modification of the microporous inorganic membrane substrate is usually carried out by sol-gel method.However,the sol-gel synthesis process is complex and controlled by many factors,which limits its application in industry.In this study,the suspension system was used to modify stainless steel hollow fiber membranes.Titanium dioxide particles of 25 nm were coated on the surface of stainless steel membranes by dip-coating method.The composite membranes of TiO2/stainless steel hollow fiber were prepared by high temperature sintering at 500℃.The effects of polyvinyl alcohol and TiO2 concentration on the morphology,pore size,pure water flux and anti-pollution properties of stainless steel hollow fiber membranes were studied.The results showed that the TiO2 functional layer was super-hydrophilic and underwater super-hydrophobic.The rejection of BSA was 90%,and the rejection of oil-water emulsion was over 99%,which had good separation and antifouling properties.