多巴胺及二乙烯三胺对PVDF膜亲水化改性及其油水分离性能  

Hydrophilic modification and oil-water separation ofPVDF membrane by dopamine and diethylenetriamine

作　　者：杜国勇[1,2] 袁巧 DU Guoyong;YUAN Qiao(School of Chemistry and Chemical Engineering,Southwest Petroleum University,Chengdu 610500,China;Oil&Gas Field Applied Chemistry key Laboratory of Sichun Province,Chengdu 610500,Cina)

机构地区：[1]西南石油大学化学化工学院,成都610500 [2]油气田应用化学四川省重点实验室,成都610500

出　　处：《功能材料》2022年第10期10222-10228,共7页Journal of Functional Materials

基　　金：油气田应用化学四川省重点实验室开放基金项目(YQKF202122)。

摘　　要：亲水疏油材料对于低浓度的含油废水具有较好的分离效果。将疏水性PVDF膜浸渍于一定质量比例的盐酸多巴胺(DA)/二乙三胺(DETA)混合溶液中,从而制备出了超亲水-水下超疏油PVDF/聚多巴胺/二乙烯三胺(PVDF/PDA/DETA)膜。采用傅里叶红外光谱仪(FTIR)、X射线光电子能谱仪(XPS)和扫描电子显微镜(SEM)对制备的改性膜进行了表征。结果表明,PDA和DETA已成功负载到PVDF膜表面。探究了浸渍时间和DA与DETA的质量比对膜表面润湿性的影响,并测试了改性膜的纯水通量、油水分离效率、重复使用率以及稳定性。结果表明,当浸渍时间为12h,DA与DETA的质量比为1∶1时所制备的改性膜具有最优异的超亲水-水下超疏油性能,水下柴油和正己烷的接触角分别达到146.1°和151.6°,与原始PVDF膜相比纯水通量提高了12.67倍,对多种油水混合物表现出优异的分离性能,经过5次油水分离后,分离效率仍可达95%以上,该膜在不同pH值溶液中浸泡12h后,水下柴油接触角仍大于140°,表现出优异的重复使用性能和稳定性能。The hydrophilic and oleophobic materials have better separation effect for low concentration of oil-bearing wastewater.Superhydrophilic and underwater superhydrophobic PVDF/polydopamine/diethyltriamine(PVDF/PDA/DETA)membranes were prepared by impregnating hydrophobic PVDF membranes with a certain mass ratio of dopamine hydrochloride(DA)/diethyltriamine(DETA)mixed solution.The modified membranes were characterized by Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS)and scanning electron microscopy(SEM).The results showed that PDA and DETA had been successfully loaded onto the PVDF membrane surface.The influences of impregnation time and mass ratio of DA to DETA on the surface wettability of the modified membrane were investigated,and the pure water flux,oil-water separation efficiency,repeat utilization rate and stability of the modified membrane were tested.The results showed that when the impregnation time was 12 h and the mass ratio of DA to DETA was 1∶1,the modified membranes had the best superhydrophilic and underwater superhydrophobic properties.The contact angle of underwater diesel oil and n-hexane reached 146.1°and 151.6°,respectively.Compared with the pristine PVDF membranes,the pure water flux increased by 12.67 times,showing excellent separation performance for various oil-water mixtures.After 5 times of oil-water separation,the separation efficiency can still reach over 95%.After soaked in solutions with different pH values for 12 h,the contact angle of underwater diesel was still greater than 140°,showing excellent reusable performance and stability.

关 键 词：PVDF膜 聚多巴胺 亲水性 疏油性 油水分离 

分 类 号：X703[环境科学与工程—环境工程]