Effects of electric fields on the removal of ultraviolet filters by ultrafiltration membranes.
Effects of electric fields on the removal of ultraviolet filters by ultrafiltration membranes.
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DOI：
10.1016/j.jcis.2012.10.055
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发表时间：
2013-03
影响因子：
9.9
通讯作者：
Xin Chen;Huiping Deng
中科院分区：
文献类型：
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作者：
Xin Chen;Huiping Deng
紫外线（UV）过滤剂代表了水中一类新的微污染物。为了有效地去除这些物质并最大限度地减少超滤过程中的污染，使用电超滤过程通过跨膜施加电场来从水中分离二苯甲酮-3（BP-3）。研究了电场对聚偏氟乙烯（PVDF）膜过滤性能的影响，包括膜阻力和截留率的影响、PVDF膜的改性以及电超滤过程中可能产生的中间产物。结果表明，电场与超滤相结合可以提高BP-3的截留率，降低过滤阻力。电场作用下PVDF膜表面发生改性，膜表面粗糙，孔径增大。接触角的减小证明了电滤处理后PVDF膜表面亲水性的改善。通过计算BP-3分子的前线电子密度，从理论上探讨了BP-3在电过滤过程中的降解机理。BP-3结构中的C3原子被证明是最具反应性的位点，这与通过气相色谱-质谱（GC-MS）分析鉴定的中间结果一致。
Ultraviolet (UV) filters represent a new class of micropollutants in water. To effectively remove these substances and minimize fouling during ultrafiltration, an electro-ultrafiltration process was used to separate benzophenone-3 (BP-3) from water by applying an electric field across the membrane. The effects of the electric field on the filtration performance, including resistance and retention, modification of polyvinylidene fluoride (PVDF) membrane and possible intermediates produced during electro-ultrafiltration, were studied thoroughly. The results clearly indicate that the combination of the electric field with ultrafiltration could increase BP-3 rejection and reduce filtration resistance. The membrane had a rougher surface and the pore size increased due to the modifications of PVDF membrane induced by the electric field. The decrease in contact angle demonstrated the improvement of hydrophilicity in the PVDF membrane surface after the electrofiltration treatment. The mechanism of BP-3 degradation in the electrofiltration was examined theoretically by calculating the frontier electron densities of the BP-3 molecule. The C3 atom in the BP-3 structure was demonstrated to be the most reactive site, which was consistent with the intermediate results identified by gas chromatography–mass spectrometry (GC–MS) analysis.