Department of Environmental Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
College of Biological Chemical Science and Engineering, Jiaxing University, Jiaxing 314001, China.
J Colloid Interface Sci. 2021 Mar;585:158-166. doi: 10.1016/j.jcis.2020.11.092. Epub 2020 Nov 25.
Although forward osmosis (FO) technology has been widely adopted for water treatment, it still faces great challenges, including low permeability and fouling problem. Herein, a novel forward osmosis membrane was developed with a stable, uniform and defect-free polyvinyl alcohol/polydopamine coated zeolitic imidazolate framework (PVA/PDA@ZIF-8) hybrid selective layer to simultaneously enhance its transport property and fouling resistance. The prepared FO membrane exhibits improved water flux without losing the selectivity, since the PDA@ZIF-8 provide additional preferential passageway for water transporting while hinder the diffusion of salt. The optimized membrane shows a higher water flux than pristine PVA membrane (14.2 vs. 8.7 L m h in FO mode, 24.3 vs. 14.8 L m h in PRO mode) with a reasonable selectivity considering as J/J value (0.44 vs. 0.4 g L in FO mode, 0.38 vs. 0.33 g L). Moreover, the dynamic fouling experiments with organic foulants (protein and polysaccharide) indicate that the prepared membrane exhibits strong antifouling property and excellent permeation recovery ability (>95.0%) due to the optimized surface property. This study opens a new avenue for treatment wastewater by developing a forward osmosis membrane based on a hydrogel/MOF hybrid selective layer.
虽然正向渗透（FO）技术已广泛应用于水处理，但仍面临着许多挑战，包括低渗透性和易堵塞问题。在此，开发了一种具有稳定、均匀且无缺陷的聚乙烯醇/聚多巴胺涂层沸石咪唑酯骨架（PVA/PDA@ZIF-8）杂化选择层的新型正向渗透膜，以同时提高其传输性能和抗污染能力。所制备的 FO 膜在保持选择性的同时提高了水通量，因为 PDA@ZIF-8 为水传输提供了额外的优先通道，同时阻碍了盐的扩散。优化后的膜在 FO 模式下的水通量高于原始 PVA 膜（14.2 比 8.7 L m h，在 PRO 模式下的水通量高于原始 PVA 膜（24.3 比 14.8 L m h），考虑到 J/J 值，具有合理的选择性（0.44 比 0.4 g L 在 FO 模式下，0.38 比 0.33 g L 在 PRO 模式下）。此外，用有机污染物（蛋白质和多糖）进行的动态污染实验表明，由于优化的表面性质，所制备的膜具有很强的抗污染性能和优异的渗透恢复能力（>95.0%）。本研究为开发基于水凝胶/金属-有机骨架杂化选择层的正向渗透膜处理废水开辟了新途径。
