以CoCl2为添加剂、N,N-二甲基乙酰胺为溶剂,采用湿法相转化工艺制备了聚丙烯腈超滤膜,对比研究了凝胶过程中磁场作用对凝胶浴液电导率、钴离子浓度的影响,并采用扫描电子显微镜、原子力显微镜观察了膜的断面与表面结构,通过超滤实验测定了膜的性能,实验结果表明:凝胶过程中的磁场作用能明显提高成膜过程中COCl2的传质速率;磁场作用使得膜断面的大孔穴数目明显减少、膜的表面粗糙度降低和膜的孔径分布变窄;磁场作用对膜的渗透通量和耐污染性的影响不大,但能提高膜的截留率.
The ultrafiltration membranes were prepared by the wet phaseinversion process from a solution consisting of CoCl2(as an additive), N, N- dimethylacetamide, and polyacrylonitrile (PAN). The effect of magnetic field in coagulation procedure on the transport rate of COCl2 were investigated by measuring the electric conductivity and the Co^2+ concentration of coagulation bath solution. The structures and the morphology of membranes were characterized by SEM and AFM. The ultrafiltration experiments were conducted to investigate the performances of membranes. The results show that the magnetic field in coagulation procedure may obviously improve the transport rate of COCl2, reduce the macrovoid numbers in the cross section of membrane, and decrease the surface roughness and the mean pore size of membrane. In addition, the magnetic field in coagulation procedure has no obvious effect on the pure water flux of a membrane and the anti - fouling ability, but it can improve the membrane rejection.