Floros Ioannis N, Kouvelos Evangelos P, Pilatos Georgios I, Hadjigeorgiou Evangelos P, Gotzias Anastasios D, Favvas Evangelos P, Sapalidis Andreas A
Institute of Nanoscience and Nanotechnology (INN), National Centre for Scientific Research (NCSR) "Demokritos", 15310 Athens, Greece.
Department of Materials Science & Engineering, University of Ioannina, 45110 Ioannina, Greece.
Polymers (Basel). 2020 Feb 5;12(2):345. doi: 10.3390/polym12020345.
This work focused on enhancing the flux on hydrophobic polymeric membranes aimed for direct contact membrane distillation desalination (DCMD) process without compromising salt rejection efficiency. Successful coating of commercial porous poly-tetrafluoroethylene membranes with poly(vinyl alcohol) (PVA) was achieved by solution dipping followed by a cross-linking step. The modified membranes were evaluated for their performance in DCMD, in terms of water flux and salt rejection. A series of different PVA concentration dipping solutions were used, and the results indicated that there was an optimum concentration after which the membranes became hydrophilic and unsuitable for use in membrane distillation. Best performing membranes were achieved under the specific experimental conditions, water flux 12.2 L·m·h [LMH] with a salt rejection of 99.9%. Compared to the pristine membrane, the flux was enhanced by a factor of 2.7. The results seemed to indicate that introducing hydrophilic characteristics in a certain amount to a hydrophobic membrane could significantly enhance the membrane distillation (MD) performance without compromising salt rejection.
这项工作专注于提高疏水性聚合物膜的通量，该膜用于直接接触膜蒸馏脱盐（DCMD）过程，同时不降低脱盐效率。通过溶液浸渍然后进行交联步骤，成功地用聚乙烯醇（PVA）涂覆了商用多孔聚四氟乙烯膜。对改性膜在DCMD中的性能进行了评估，包括水通量和脱盐率。使用了一系列不同浓度的PVA浸渍溶液，结果表明存在一个最佳浓度，超过该浓度后膜变得亲水，不适用于膜蒸馏。在特定实验条件下获得了性能最佳的膜，水通量为12.2 L·m²·h⁻¹[LMH]，脱盐率为99.9%。与原始膜相比，通量提高了2.7倍。结果似乎表明，在一定程度上给疏水膜引入亲水特性可以显著提高膜蒸馏（MD）性能，同时不影响脱盐效果。
