GO/PVDF复合微滤膜制备及其性能表征

Preparation and characterization of GO/PVDF composite microfiltration membranes

为了探究GO对PVDF微滤膜亲水性及渗透性能的影响,以GO作为无机添加剂,利用相转化法制备了高性能GO/PVDF复合微滤膜,先后考察了铸膜液预挥发时间、凝固浴温度对复合膜性能的影响,同时从成膜机理的角度上分析了GO投加量对复合膜结构和性能的影响,确定了最优制膜配方.结果表明:保持铸膜液预挥发时间为0 s、凝固浴温度为29℃时更有利于提高膜纯水通量和截留率;投加GO后大幅度提高了膜亲水性,当GO的相对质量分数(即相对于PVDF的质量分数)为1.5%时,膜表面形成了致密的多孔结构,使纯水通量提高了87.6%,对BSA的截留率从63.56%增加到了71.27%.

To investigate the influence of GO on hydrophilicity and permeability of PVDF microfiltration membrane, GO/PVDF composite microfiltration membrane was prepared via phase inversion method with GO as additive. The influence of casting solution evaporation time and coagulation bath temperature on membrane performance was investigated. Furthermore, the effects of GO dosage on the structures and performance of composite membranes were analyzed in terms of the mechanism of membrane preparation, and the optimal membrane formula was determined. The results show that keeping the casting solution evaporation time at 0 s and coagulation bath temperatureat 29 ℃ can improve pure water flux and rejection of the membrane. When the GO was added into the membrane,the hydrophilicity is enhanced obviously, and the compact pores take shape on the surface layer of compositemembrane, when the GO content is 1.5%, thus the pure water flux of composite membrane is approximately87.6% higher than that of the original membrane, and the rejection to BSA is enhanced from 63.56% to 71.27%.