石墨炭纳米颗粒改性聚砜支撑层制备正渗透复合膜  

Polysulfone Supporting Layer Modified by Graphite Carbon Nanoparticles to Fabricate TFC Membrane for Forward Osmosis Application

作　　者：姚子成 肖方锟 刘兆峰[1] 张大鹏 朱桂茹[1] YAO Zicheng;XIAO Fangkun;LIU Zhaofeng;ZHANG Dapeng;ZHU Guiru(College of Chemistry and Chemical Engineering,Ocean University of China,Qingdao 266100,China)

机构地区：[1]中国海洋大学化学化工学院,青岛266100

出　　处：《材料导报》2021年第8期196-200,共5页Materials Reports

基　　金：中央高校基本科研业务费专项(201964020);国家自然科学基金(U1607124)。

摘　　要：正渗透膜分离技术是以膜两侧的渗透压差作为驱动力,因此能耗低,符合绿色节约型社会的发展需求。然而,主流的聚酰胺复合膜在正渗透过程中存在内浓差极化现象,使其水通量远小于理论值。因此,改性正渗透复合膜减小其内浓差极化以提高水通量,对促进正渗透技术大规模应用具有重要的意义。本研究采用相转化法制备了掺杂石墨炭纳米颗粒的聚砜支撑层,通过间苯二胺和均苯三甲酰氯在支撑层表面进行界面聚合制备了聚酰胺薄层复合膜(Thin-film composite,TFC)。采用扫描电子显微镜和接触角分析仪对聚砜支撑层和TFC复合膜进行表征,观察膜表面形貌和亲水性,考察不同石墨炭纳米颗粒添加量对正渗透膜性能的影响。结果表明:在基膜中掺杂石墨炭纳米颗粒会使基膜表面孔隙率增大,表面亲水性增强,结构参数减小,这表明内浓差极化得到有效的改善。当石墨炭纳米颗粒添加量为0.01%(质量分数)时,水通量在活性层朝向汲取液(AL-DS)时达到22.4 L/(m~2·h),相比未改性的正渗透膜增加了96.7%,这表明新型石墨炭材料可以有效地提高聚酰胺复合膜的正渗透分离性能。Forward osmosis(FO)membrane-based separation process forced by the osmotic pressure,is particularly attractive due to the lower energy consumption.The polyamide thin-film composite(TFC)membrane has achieved a dominant position in FO field.However,internal concentration polarization(ICP)is a serious challenge in the TFC FO membrane which causes the experimental water flux significantly lower than the theoretical value.Therefore,modification of the polyamide TFC membrane to reduce the ICP will be necessary to enhance the separation perfor-mance of FO.In this study,polysulfone(PSF)supporting membrane doped with graphite carbon nanoparticles was prepared by phase conversion method.Polyamide active layer was prepared via interfacial polymerization of m-phenylenediamine and trimesoyl chloride on the PSF surface of supporting layer to fabricate the thin-film composite(TFC)membrane.Scanning electron microscope and contact angle analyzer were used to characterize the PSF supporting membrane and TFC membrane.The results showed that the hydrophilicity and surface porosity of the graphite carbon nanoparticles incorporated PSF membrane was enhanced;the phenomenon of internal concentration polarization was abate;the corresponding permeability was improved and water flux increased.When the additional amount of graphite carbon nanoparticles was 0.01 wt%,the water flux with the active layer toward the draw solution(AL-DS)reached 22.4 L/(m~2·h),which increased by 96.7%compared with the unmodified FO membrane.It indicated that the new graphite carbon nanoparticles can effectively improve the forward osmosis separation performance of polyamide composite membrane.

关 键 词：石墨炭纳米颗粒 聚砜基膜 聚酰胺复合膜 正渗透 水通量 

分 类 号：TQ028[化学工程]