聚吡咯电响应膜的油水分离及抗污染性能

PPy electro-responsive membrane for oil/water separation and its anti-fouling performance

膜分离是重要的油水分离技术,但由于高分子膜材料的疏水性,在油水分离过程中易发生膜的油污黏附和堵塞,导致膜分离效果下降和膜工作寿命缩短。该研究采用共混改性-原位化学氧化一步法制备了聚吡咯(PPy)导电膜,发现PPy掺杂后膜表面具有更多微纳凸起结构,粗糙度增加;施加还原电位可调节膜孔径收缩并增加亲水性,提高油水分离性能和抗污染能力。持续施加-1 V电压时,PPy导电膜孔径收缩10.59%,水接触角由96°降低至45°;此时油水分离效率高达99.38%。经过5次乳化液污染循环实验后,PPy导电膜仍可保留77.11%的通量,相较未改性时膜通量提升5倍。制备的PPy导电膜兼具良好的油水分离效果与抗油污性能,在含油废水处理领域具有较好的应用前景。

Membrane separation is an important technique for oil-water separation.However,due to the hydrophobic nature of polymeric membrane materials,membranes are prone to oil fouling and clogging during oil-water separation,resulting in reduced separation efficiency and a shortened lifetime.Herein,a novel polypyrrole(PPy)conductive membrane was prepared by a one-step method of blending modification and in situ chemical oxidation.The PPy-doped membrane surface exhibited more micro-nano bulged structure and higher roughness than unmodified one.The application of reduction potential was found to shrink the pore size and increase the hydrophilicity of the PPy conductive membrane,which can improve the oil-water separation and anti-fouling performance.When a constant voltage of-1 V was applied,the pore size of the PPy conductive membrane shrank by 10.59%and the water contact angle decreased from 96°to 45°.At the same time,the oilwater separation efficiency reached up to 99.38%.After 5 cycles of emulsified liquid fouling experiments,the PPy conductive membrane still retained 77.11%of its original flux,which is a fivefold increase compared with the flux of the unmodified membrane.The prepared PPy conductive membrane exhibits an excellent oil-water separation performance and resistance to oil fouling,showing great application prospects in oily wastewater treatment.