纳米颗粒对PVDF超滤膜性能影响的研究

Study on effect of nano-sized particles on PVDF ultrafiltration membrane performance

通过纳米共混的方法,利用纳米铝(Al2O3)及纳米二氧化钛(TiO2)颗粒来合成PVDF超滤膜.实验中通过相转化法制得:PVDF,PVDF/Al2O3,PVDF/TiO2,PVDF/Al2O3/TiO2,四种超滤膜,并通过超滤实验测试了四种膜的纯水通量及抗污染性.通过测定膜表面和水之间的接触角来定量分析比较膜表面的亲水性.实验中利用SEM观察了膜的表面和内部微观结构.测定并讨论了纳米颗粒对膜渗透性能、抗污染性及膜形态和结构的影响.实验结果表明由于纳米颗粒的加入,膜的特性及性能得到了极大的改善和提高.而且PVDF/Al2O3/TiO2共混膜是所有被测定的膜中性能最好的.

Polyvinylidene fluoride （PVDF） uhrafiltration （UF） membranes are modified by u- niformly dispersing nano-sized alumina （Al2O3 ） and titanium dioxide （TiO2 ） particles in the PVDF casting solution. The PVDF, PVDF/Al2O3, PVDF/TiO2 and PVDF/Al2O3/TiO2 membranes are prepared by the phase-inversion processes. The permeation flux and anti-fouling performance of wet membranes were examined in the UF laboratory unit. The hydrophilicity changes of the membranes are detected by measuring the contact angle between water and membrane surface. The membrane surface and cross-sectional structures are observed by scanning electron microscopy （SEM）. The effect of nanometer particles on the membrane permeation properties, anti-fouling performances,and membrane morphologies and structures are examined and discussed. The experimental results indicated that the membrane properties and performances are significantly improved due to the addition of nano-sized particles and PVDF/ Al2O3/TiO2 composite membrane was the best one in all of the membranes mentioned above.