Department of Chemical Engineering, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai 200240, P. R. China.
Langmuir. 2016 Dec 20;32(50):13358-13366. doi: 10.1021/acs.langmuir.6b03627. Epub 2016 Dec 7.
Oil/water separation has inspired much research interest because of the damages caused to our natural environment due to oily wastewater. As a leader of advanced separation materials, electrospun polymeric fibrous mats having the properties of special surface wettability, high specific surface area, and high porosity will be a good membrane material for the separation of oily wastewater. Herein, we first prepared pH-responsive polymer poly(dimethylsiloxane)-block-poly(4-vinylpyridine) (PDMS-b-P4VP) mat using electrospinning technology. The PDMS-b-P4VP fibrous mat with a thickness of around 250 μm exhibits good pH-switchable oil/water wettability and is able to effectively separate oil or water from layered oil/water mixtures by gravity driven through adjusting the pH value. Stemming from its porous structure and pH-switchable superwettability, the electrospun PDMS-b-P4VP fibrous mat achieved controllable separations with high fluxes of approximately 9000 L h m for oil (hexane) and 27 000 L h m for water. In addition, extended studies on the polymer/silica nanoparticulate (silica NP) composite fibrous mats show that the addition of an inorganic component improves the thermal stability, pH-switchable wettability, and separation performance of the fibrous mats (approximately 9000 L h m for hexane and 32 000 L h m for water). It can be concluded from the results that both polymer fibrous mats and silica-filled composite fibrous mats are good candidates for on-demand layered oil/water mixture separation.
由于含油废水对我们的自然环境造成的破坏，油水分离引起了广泛的研究兴趣。作为先进分离材料的领导者，具有特殊表面润湿性、高比表面积和高孔隙率的静电纺聚合物纤维毡将成为分离含油废水的良好膜材料。在此，我们首先使用静电纺丝技术制备了 pH 响应聚合物聚二甲基硅氧烷-嵌段-聚（4-乙烯基吡啶）（PDMS-b-P4VP）毡。厚度约为 250μm 的 PDMS-b-P4VP 纤维毡具有良好的 pH 可切换油水润湿性，通过调节 pH 值，能够有效地将油或水从分层的油/水混合物中通过重力驱动进行分离。由于其多孔结构和 pH 可切换超润湿性，静电纺 PDMS-b-P4VP 纤维毡实现了可控分离，油（己烷）通量约为 9000 L h m-2，水通量约为 27000 L h m-2。此外，对聚合物/二氧化硅纳米颗粒（SiO2NP）复合纤维毡的进一步研究表明，添加无机成分可以提高纤维毡的热稳定性、pH 可切换润湿性和分离性能（约 9000 L h m-2用于己烷和 32000 L h m-2用于水）。结果表明，聚合物纤维毡和填充二氧化硅的复合纤维毡都是按需分离层状油/水混合物的良好候选材料。
