PVDF/PEI-EDA亲疏水复合膜的制备及其抗污染性能

Preparation of Hydrophilic/Hydrophobic PVDF/PEI-EDA Composite Membrane and Its Anti-Fouling Performance

为解决疏水性污染物对膜的污染问题,利用静电纺丝的方法制备了具有抗污染性能的聚偏氟乙烯/聚醚酰亚胺-乙二胺(PVDF/PEI-EDA)亲疏水复合膜,对其进行了表征;以含疏水性污染物(油污)的Na Cl水溶液作为进料溶液进行了直接接触式膜蒸馏脱盐和抗污染实验,并与商业的PVDF疏水膜进行了对比。结果表明,复合膜厚度为340μm,平均孔径0.677μm,孔隙率72.4%;膜表面呈纳米纤维状,具有明显的酰胺基团,膜表面在空气中水接触角为5.6°,在水相中的油接触角为143°。复合膜蒸馏运行稳定,脱盐、抗污染膜蒸馏平均通量分别为5.5、4 kg/(m^2·h),可以有效的防止疏水性污染物(油污)的污染。而商业的PVDF疏水膜膜蒸馏过程不能维持稳定运行。

To solve the problem of membrane fouling by hydrophobic pollutants,hydrophibic/hydrophobic poly（vinylidene fluoride）/poly（etherimide）-ethylenediamine（PVDF/PEI-EDA）composite membrane with antifouling property was prepared by electrospinning and it was characterized.The direct contact membrane distillation desalination and antifouling experiment were carried out using Na Cl aqueous solution containing hydrophobic pollutants（oil pollution）as the feed solution,and it was compared with the commercial PVDF hydrophobic membrane.The result showed that,the thickness of the composite membrane was 340μm,the average pore size was 0.677μm and the porosity was 72.4%.The surface of the composite membrane was fibrous and had obvious amide groups.The water contact angle in-air was 5.6°,and the oil contact angle underwater was 143°.The direct contact membrane distillation process with the composite membrane ran stably.The average flux of the desalination and antifouling membrane distillation were 5.5 kg/（m^2·h）and 4 kg/（m^2·h）respectively.The composite membrane could effectively prevent the pollution of hydrophobic pollutions.While the direct contact membrane distillation with the commercial PVDF hydrophobic membrane could not run stably.