Membrane fouling is the main bottleneck that hinders the applications of membrane bioreactors (MBRs). 4,5-Dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT), as an environmentally-acceptable antifouling biocide, was mixed with Polyvinylidene fluoride (PVDF) to fabricate hollow fiber membrane via non-solvent induced phase separation (NIPS), which was able to effectively improve the antifouling performance of the membranes in this work. Overall research of the prepared membrane revealed that membranes with 3 wt% DCOIT exhibited the optimum antifouling performance. With the addition of DCOIT, hydrophilicity and pure water flux of 3 wt% DCOIT membranes maintained remarkable improvement by 22.9% and 64.6% than that of membranes without DCOIT. Meanwhile, the surface morphologies of 3 wt% DCOIT membranes were smoother than the control group in terms of SEM and AFM images, which was beneficial to alleviate membrane fouling. In antifouling experiments, the flux variation rate of membranes with 3wt% DCOIT filtrated in bull serum albumin, sodium alginate and humic acid solution were 81.42%, 54.25%, 50.5%, while membrane without DCOIT were 64.6%, 24.72% and 29%, respectively. Similar results were obtained by filtrating anaerobic sludge for 24 h. The flux variations of 3 wt% DCOIT membranes were 59.4%, 47.8% and 46.0%, respectively in three stages. However, the flux variations of membranes without DCOIT were 44.8%, 36.7% and 19.8%, respectively, which showed better antifouling ability and higher flux recovery efficiency The novel membranes would provide some theoretical basis and technical support for the rational combinations in elevating the overall antifouling properties of membranes.

中文翻译：

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PVDF-DCOIT复合中空纤维膜的制备及防污性能

膜污染是阻碍膜生物反应器（MBR）应用的主要瓶颈。4,5-Dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) 作为一种环境可接受的防污杀菌剂，与聚偏二氟乙烯 (PVDF) 混合，通过非溶剂诱导相制备中空纤维膜分离（NIPS），在这项工作中能够有效提高膜的防污性能。对所制备膜的总体研究表明，含有 3 wt% DCOIT 的膜表现出最佳的防污性能。添加DCOIT后，3 wt% DCOIT膜的亲水性和纯水通量比没有DCOIT的膜保持了22.9%和64.6%的显着提高。同时，3 wt% DCOIT 膜的表面形貌在 SEM 和 AFM 图像方面比对照组更光滑，有利于减轻膜污染。在防污实验中，在牛血清白蛋白、海藻酸钠和腐植酸溶液中过滤的3wt% DCOIT膜的通量变化率为81.42%、54.25%、50.5%，而不含DCOIT的膜的通量变化率为64.6%、24.72%和29%，分别。通过过滤厌氧污泥 24 小时获得了类似的结果。3 wt% DCOIT 膜的通量变化在三个阶段分别为 59.4%、47.8% 和 46.0%。然而，没有 DCOIT 的膜的通量变化分别为 44.8%、36.7% 和 19.8%，