共涂覆法改性聚醚砜膜络合超滤除锑应用研究

Study on Application of Polyethersulfone Membrane with Hybrid Coating Modification in Complexation-Ultrafiltration Process for Antimony Removal

针对商业聚醚砜(PES)膜表面亲水性差,在络合超滤除锑过程中膜通量损失较大的问题。采用一步共涂覆改性法,通过在PES基膜表面形成聚多巴胺和二氧化硅纳米颗粒杂化涂层,得到高亲水性表面。对改性膜进行了表征和络合超滤实验。结果表明,优化改性条件为TEOS投加量0.6 g、时间9 h,此时制备的膜接触角仅为17.5°,亲水性能显著提高;超滤过程中膜通量有效提升,而且锑截留率可从改性前的75.2%提高至77.4%。改性膜在循环超滤实验中只经过清水冲洗即可恢复90%以上的初始膜通量,具有较好的运行稳定性。

In the complexation-ultrafiltration process for antimony removal,the membrane flux of commercial polyethersulfone(PES)declined seriously because of its poor hydrophilic membrane surface.A one-step hybrid coating method was applied to prepare high hydrophilic membrane surface,which formed a hybrid coating with dopamine and silica nanoparticles on PES based membrane surface.The modified membrane was characterized and applied in complexation-ultrafiltration experiment.The results showed that,the optimized modification condition was that the TEOS dosage was 0.6 g and the time was 9 h,the contact angle of the prepared membrane was only 17.5°under this condition,the hydrophilic performance and membrane flux improved remarkably in the ultrafiltration process.Furthermore,the retention rate of antimony could be increased from 75.2%to 77.4%.The cycle experiments indicated that the membrane flux could be restored to more than 90%of the initial one just with water cleaning,and it had a stable operation performance.