基于石墨烯量子点TFN膜的制备与性能

Preparation and performance of TFN membrane based on graphene quantum dots

利用哌嗪与均苯三甲酰氯的界面聚合反应将石墨烯量子点(GQDs)作为水相添加剂掺入到纳滤膜分离皮层中构成薄层纳米复合膜GQDs-PA-TFN,并采用傅里叶变换红外光谱、X射线光电子能谱、扫描电子显微镜、原子力显微镜、Zeta电位、水接触角等进行表征分析.研究发现,即使水相中加入的GQDs量较低,GQDs-PA-TFN膜的表面结构、荷负电性和亲水性能也可得到有效改善.同时为了保证GQDs-PA-TFN膜对小分子物质的高效截留,在不牺牲膜渗透通量的情况下进行了二次界面聚合反应.当GQDs添加量为质量分数0.003%,在实验得到的最佳反应条件下制备的GQDs-PA-TFN膜在0.6 MPa压力下渗透通量为36.9 L/(m^(2)·h),是未添加GQDs的薄层复合膜的1.4倍,对MgSO4的截留率为95.8%.

Graphene quantum dots(GQDs)was incorporated into the separation functional layer as an aqueous additive by interfacial polymerization of piperazine and trimesoyl chloride to preparation membrane GQDs-PA-TFN.The samples were characterized by fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,scanning electron microscope,atomic force microscope,Zeta potential and water contact angle.It was found that the surface structure,electronegativity and hydrophilicity of the GQDs-PA-TFN membrane were effectively improved even though the content of GQDs in the aqueous phase was low.At the same time,in order to ensure the efficient interception of small molecules by GQDs-PA-TFN membrane,the secondary interfacial polymerization reaction was carried out without sacrificing the flux of the TFN membrane.With the addition of GQDs at 0.003%,the permeation of the GQDs-PA-TFN membrane prepared under the optimal reaction conditions obtained by the experiment reached 36.9 L/(m^(2)·h)under the pressure of 0.6 MPa,which was 1.4 times that of the thin-film compsite membrane without GQDs,and the rejection of MgSO4 was 95.8%.