PVDF-MMT-PVA增强型中空纤维膜的制备及性能研究

杜永涛 杨梦林 张克勤 孟凯

摘 要：聚偏氟乙烯（PVDF）中空纖维膜在使用中易受污染而出现膜孔堵塞和水通量减少的现象，减短了膜的使用周期和寿命，改善膜的亲水性是提高膜的抗污染性的有效方法。以PVDF为成膜聚合物，聚乙烯醇（PVA）和纳米蒙脱土（MMT）作为改性添加剂，基于非溶剂相转化法（NIPS）制备了新型PVDF-MMT-PVA增强型中空纤维膜，同时，制备了纯PVDF、PVDF/PVA膜作为比较对象。通过扫描电镜（SEM）、衰减全反射-傅里叶变换红外光谱（ATR-FTIR）等方法探究了PVA和MMT对PVDF中空纤维膜的表面结构和相关性能的影响。结果表明：PVA的加入可以有效提高膜的亲水性能，但PVDF/PVA相容性较差;MMT的加入改善了PVDF/PVA的相容性，抑制了大孔缺陷的形成。当PVDF与PVA质量分数比为90∶10、MMT质量分数为0.5%时，所制备的中空纤维膜性能最优，纯水通量320 L/（m2·h），截留率大于94%，清洗后膜水通量恢复率大于92%，与纯PVDF膜相比，膜抗污染性能得到明显提高。

关键词：中空纤维膜;PVDF;MMT;膜污染

中图分类号： TB332

文献标志码：A

文章编号：1009-265X（2021）06-0019-10

收稿日期：2020-09-02 网络首发日期：2021-01-25

基金项目：中国纺织工业联合会科技指导项目（2018052）

作者简介：杜永涛（1996-），男，山东临沂人，硕士研究生，主要从事中空纤维膜方面的研究。

通信作者：孟凯，E-mail：mk2009@suda.edu.cn

Study on Preparation and Properties of the PVDF-MMT-PVA ReinforcedHollow Fiber Membranes

DU Yongtao1， YANG Menglin2， ZHANG Keqin1，3， MENG Kai1，3

（1.College of Textile and Clothing Engineering， Soochow University， Suzhou 215123， China;

2.College ofTextile & Clothing， Qingdao University， Qingdao 266071， China;

3.Huzhou State Environmental ProtectionIndustry Application Technology Research Institute， Huzhou 313099， China）

Abstract： Polyvinylidene fluoride （PVDF） hollow fiber membranes are prone to fouling during use， which can lead to membrane pore blocking and water flux reduction， and shorten the use cycle and service life of membranes. An effective way to improve hydrophilicity is to improve the anti-fouling performance of membrane. PVDF-MMT-PVA reinforced hollow fiber membranes were prepared by non-solvent induced phase separation （NIPS）， with PVDF as the film forming polymer， polyvinyl alcohol （PVA） and nano-montmorillonite （MMT） as the modifying additives. At the same time， pure PVDF and PVDF/PVA membranes were prepared as comparison objects. The effects of PVA and MMT on the surface structure and related properties of PVDF hollow fiber membranes were investigated by means of SEM and ATR-FTIR. The results showed that the hydrophilicity of the membrane can be improved through the addition of PVA， but the compatibility of PVDF/PVA was poor. The compatibility of PVDF and PVA can be improved by adding MMT， which also restrained the formation of macroporous defects in PVDF-MMT-PVA hollow fiber membranes. When the mass fraction ratios of PVDF/PVA and MMT were 90：10 and 0.5% respectively， the hollow fiber membranes showed the best performance and a pure water flux of 320 L/（m2·h）. The membrane rejection rate and water flux recovery rate after cleaning were greater than 94% and 92% respectively. Compared with pure PVDF membranes， the anti-fouling properties of the PVDF-MMT-PVA membranes were obviously improved.

Key words： hollow fiber membranes; PVDF; MMT; membrane fouling

膜分离技术在水处理领域中已具有广泛应用[1-2]，将生物降解技术和膜分离技术相结合的膜生物反应器（MBR）具有出水水质优良，占地面积小，剩余污泥少等优点，在中水回用、工业废水、生活污水处理中受到越来越多的重视[3-4]。聚偏氟乙烯（PVDF）是一种半结晶聚合物，因具有优异的化学稳定性、耐热性及易成膜等特点被广泛应用于制备MBR中空纤维膜。……