基于双层复合基膜的界面聚合正渗透膜的制备及表征

Preparation and characterization of forward osmosis membranes based on dual-layer composite support

以不同结构的双层PEEK-WC中空纤维为基膜制备了界面聚合正渗透复合膜.基膜外表面孔径会对界面聚合层产生影响,小孔径的表面有利于形成更致密、截留性能更高的聚酰胺层.支撑层孔隙率提升和表面孔径及孔隙率增大会提高通量.内浓差极化现象不仅受支撑层的影响,还受到汲取液种类的影响.与NaCl相比,使用Na_2SO_4做汲取液使水通量提高1.3~1.6倍,反向盐通量降低76%~95%.

FO membranes were prepared by interfacial polymerization using double-layer PEEK-WC hollow fiber membranes with different structures as support.The outer surface of the support influenced the interface polymerized layer.The polyamide layer on the surface with smaller pore size was denser.Higher porosity and increased pore size/porosity on membrane surface enhanced membrane flux.The ICP phenomenon was affected not only by the support layer,but also the type of draw solution.In comparison with NaCl,the use of Na2 SO4 as draw solution increased the water flux by 1.3～1.6 times and reduced the reverse salt flux decreased by 76%～95%.