Liu Jie, Zhong Zhencheng, Ma Rui, Zhang Weichen, Li Jiding
National Institute of Clean and Low Carbon Energy, Beijing 102209, China.
The State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
Membranes (Basel). 2016 Jun 21;6(2):35. doi: 10.3390/membranes6020035.
In this study, flat sheet asymmetric polyphenylsulfone (PPSU) ultrafiltration membranes with enhanced antifouling properties were prepared with a non-solvent induced phase separation (NIPS) method through compound additives containing a polymeric pore-forming agent, a small molecular non-solvent and a surfactant. The formation processes of the porous asymmetric membranes with different kinds of additives were studied in detail, and the microstructure controllable preparation of membrane was achieved by establishing a bridge between the membrane preparation parameters and separation performances. All prepared membranes were characterized by using a scanning electron microscope (SEM), contact angle analysis, porosity, maximum pore size, water and BSA solution permeability studies. The performance efficiency of the membrane was evaluated by using BSA as a model foulant in terms of permeability, solute rejection (R), Rm (membrane inherent resistance), Rc (cake layer resistance), and Rp (pore plugging resistance). The results showed that when the compound additives were used, the inter-connected pores were observed, maximum pore size, contact angle and membrane filtration resistance decreased, while the porosity increased. When PVP compound additives were added, the water flux increased from 80.4 to 148.1 L/(m²·h), the BSA rejection increased from 53.2% to 81.5%. A similar trend was observed for membranes with added PEG compound additives; the water flux and BSA rejection simultaneously increased. The filtration resistance decreased as a result of compound additives. The uniformity of membrane and the number of effective pores could be enhanced by adding compound additives through the cooperation of different additives.
在本研究中，采用非溶剂诱导相分离（NIPS）法，通过含有聚合物致孔剂、小分子非溶剂和表面活性剂的复合添加剂制备了具有增强抗污染性能的平板不对称聚砜（PPSU）超滤膜。详细研究了添加不同种类添加剂时多孔不对称膜的形成过程，并通过在膜制备参数和分离性能之间建立联系，实现了膜的微观结构可控制备。所有制备的膜均采用扫描电子显微镜（SEM）、接触角分析、孔隙率、最大孔径、水和牛血清白蛋白（BSA）溶液渗透性研究进行表征。以BSA作为模型污染物，从渗透率、溶质截留率（R）、膜固有阻力（Rm）、滤饼层阻力（Rc）和孔堵塞阻力（Rp）等方面评估了膜的性能效率。结果表明，使用复合添加剂时，观察到相互连通的孔，最大孔径、接触角和膜过滤阻力降低，而孔隙率增加。添加聚乙烯吡咯烷酮（PVP）复合添加剂时，水通量从80.4增加到148.1 L/(m²·h)，BSA截留率从53.2%增加到81.5%。添加聚乙二醇（PEG）复合添加剂的膜也观察到类似趋势；水通量和BSA截留率同时增加。复合添加剂降低了过滤阻力。通过不同添加剂的协同作用添加复合添加剂，可以提高膜的均匀性和有效孔数量。
