具有PDA-UiO-66中间层耐溶剂复合纳滤膜的制备及性能

Preparation and properties of solvent-resistant composite nanofiltration membrane with PDA-UiO-66 interlayer

摘要:

通过多巴胺和UiO-66纳米颗粒共沉积在经1,6-己二胺交联的聚醚酰亚胺（PEI）基膜上构建了PDA-UiO-66纳米复合中间层，并在中间层上进行界面聚合制备耐溶剂复合纳滤膜（TFN-U）。通过FTIR、XRD、SEM、AFM、水接触角测量仪等对膜结构进行表征与分析，同时探究了UiO-66质量浓度对TFN-U膜耐溶剂性能、耐污染性能以及运行稳定性的影响。结果表明，PDA-UiO-66纳米复合中间层的引入能提高TFN-U膜的渗透通量，当UiO-66纳米颗粒质量浓度为0.2 g/L时，TFN-U2膜纯水通量提高至63.83 L/(m2·h)，甲醇通量为28.50 L/(m2·h)，且对刚果红水溶液和刚果红甲醇溶液的截留率仍可保持98.24和93.16%，在经过无水乙醇、丙酮、乙酸乙酯、正己烷以及DMF有机溶剂浸泡24 h后，其对刚果红的截留率均保持在94%以上，通量恢复率达到78.1%，在连续24 h过滤刚果红甲醇溶液后，该膜的甲醇通量为14.13 L/(m2·h)，截留率为98.29%，表明TFN-U2膜具有良好的耐溶剂性、耐污染性以及一定的稳定性。

Abstract:

In this study, dopamine and UiO-66 nanoparticles were co-deposited on polyetherimide (PEI) base membrane crosslinked by 1,6-hexamethylenediamine to construct PDA-UiO-66 nanocomposite interlayer, and the solvent-resistant composite nanofiltration membrane (TFN-U) was prepared by interfacial polymerization on the interlayer. The membrane structure was characterized and analyzed by FTIR, XRD, SEM, AFM, water contact angle meter, etc. Meanwhile, the influence of UiO-66 mass concentration on the solvent resistance, pollution resistance and operation stability of TFN-U membrane was explored. The results show that the introduction of PDA-UiO-66 nanocomposite interlayer can improve the permeation flux of TFN-U membrane. When the mass concentration of UiO-66 nanoparticles is 0.2 g/L, the pure water flux of TFN-U2 membrane is increased to 63.83 L/(m2 h) and the methanol flux is 28.50 L/(m2 h), and the rejection rate of Congo red aqueous solution and Congo red methanol solution can still maintain 98.24 and 93.16%. After soaking in anhydrous ethanol, acetone, ethyl acetate, n-hexane and DMF for 24 hours, the rejection rate of Congo red remained above 94%, and the flux recovery rate reached 78.1%. After continuously filtering Congo red methanol solution for 24 hours, the methanol flux of the membrane was 14.13 L/(m2 h) and the rejection rate was 98.29%, which indicated that TFN-U2 membrane had good solvent resistance, pollution resistance and certain stability.