氯化钠凝固浴对PVDF超滤膜耐氯性的影响  

Effect of Sodium Chloride Coagulation Bath on Chlorine Resistance of PVDF UF Membrane

作　　者：张建林 崔航宇 张书嘉 马欣悦 李凯[4] ZHANG Jianlin;CUI Hangyu;ZHANG Shujia;MA Xinyue;LI Kai(Weifang Municipal Engineering Design and Research Institute Co.,Ltd.,Weifang 261000,China;Hebei Water Resources Planning and Design Institute Co.,Ltd.,Shijiazhuang 050001,China;China United Engineering Co.,Ltd.,Hangzhou 310052,China;School of Environmental and Municipal Engineering,Xi'an University of Architecture and Technology,Xi'an 710005,China)

机构地区：[1]潍坊市市政工程设计研究院有限公司,山东潍坊261000 [2]河北省水利规划设计研究院有限公司,河北石家庄050001 [3]中国联合工程有限公司,浙江杭州310052 [4]西安建筑科技大学环境与市政工程学院,陕西西安710005

出　　处：《净水技术》2025年第2期65-71,共7页Water Purification Technology

基　　金：陕西省自然科学基金项目(2023-JC-YB-448)。

摘　　要：【目的】研究旨在探究非溶剂致相分离法制备聚偏氟乙烯(PVDF)超滤膜过程中凝固浴组成对膜耐氯性的影响。【方法】采用纯水和质量浓度为200 g/L的氯化钠(NaCl)溶液作为凝固浴制备的PVDF膜分别记为M0和M200,通过静态加速老化试验考察了次氯酸钠(NaClO)老化对其化学组成和性质的影响,采用腐殖酸(HA)作为模型有机物考察了NaClO老化前后膜抗污染性能的变化。【结果】与纯水凝固浴相比,NaCl溶液作为凝固浴使PVDF膜中极性β晶型的比例由69%提高至81%,膜表面纯水接触角由82.8°降低至75.1°;NaClO老化使2种膜上亲水添加剂均发生了氧化流失,亲水性有所降低,但膜晶型结构未发生明显变化,NaClO老化后M200膜中较高比例的极性β晶型使其亲水性仍然高于NaClO老化后M0膜;两周期HA过滤试结束时M0和M200膜的通量分别下降至初始通量的26%和48%,M200膜的可逆和不可逆污染阻力分别比M0膜小54%和28%,表明M200膜的抗污染性能明显好于M0膜;NaClO老化造成的膜亲水性降低使2种膜的抗污染能力均有所下降,但M200膜的变化幅度小于M0膜,两周期HA过滤试验结束时老化后M0和M200膜通量分别下降到其初始通量的13%和40%,老化后M200膜的可逆和不可逆污染阻力分别比老化后M0膜低71%和62%。【结论】Na Cl凝固浴提高了PVDF膜中极性β晶型的比例,减缓了NaClO老化造成的膜抗污染性能的下降,提升了膜的耐氯性。[Objective]The aim of this study is to investigate effect of coagulation bath composition on chlorine resistance of polyvinylidene fluoride(PVDF)UF membranes prepared by non-solvent induced phase separation method.[Methods]PVDF membranes were prepared using pure water(M0)and 200 g/L sodium chloride(NaCl)solution(M200)as coagulation bath,respectively.Effects of sodium hypochlorite(NaClO)aging on the chemical composition and properties of membranes were investigated through static accelerated aging experiments.Humic acid(HA)was used as a model organic foulant to examine the changes in antifouling performance of membranes before and after NaClO aging.[Results]Compared with the pure water coagulation bath,the use of NaCl solution as the coagulation bath increased the proportion of polarβ-phase in the PVDF membrane from 69%to 81%,resulting in a decrease in pure water contact angle on membrane surface from 82.8°to 75.1°.NaClO aging led to oxidation loss of hydrophilic additives on both membranes,resulting in a reduction in hydrophilicity.However,there was no significant change in the crystal structure of the membranes.After NaClO aging,the higher fraction of polarβ-PVDF phase in the M200 membrane made it more hydrophilic than M0.At the end of two cycles HA filtration experiments,the flux of the M0 and M200 membranes decreased to 26%and 48%of their initial flux,respectively.The reversible and irreversible fouling resistances of the M200 membrane were 54%and 28%lower than those of the M0 membrane,indicating that the anti-fouling performance of the M200 membrane was significantly better than that of the M0 membrane.Although the reduction in hydrophilicity caused by NaClO aging resulted in decreased anti-fouling performance for both membranes,the change in M200 membrane was less pronounced than that in the M0 membrane.By the end of the two cycles HA filtration experiments,the flux of the aged M0 and M200 membranes decreased to 13%and 40%of their initial flux,respectively.The reversible and irreversible fouling resistan

关 键 词：超滤膜 非溶剂致相分离 凝固浴 聚偏氟乙烯(PVDF) 耐氯性 

分 类 号：TQ051[化学工程]