改性氧化石墨烯复合纳滤膜的制备及性能研究

发布时间：2018-04-30 06:06

本文选题：氧化石墨烯 + 羧基化氧化石墨烯　；参考：《浙江工业大学》2017年硕士论文

【摘要】：氧化石墨烯(GO)表面分布着很多含氧官能团,这些基团使氧化石墨烯具有良好的分散性、亲水性、与聚合物的相容性等,还为进一步改性提供了大量的活性位点,其中羧基化氧化石墨烯(CFGO)因为表面大量羧基的去质子化而具有更好的水溶性,与聚合物的相容性也更好。本文以聚砜为底膜,哌嗪和均苯三甲酰氯为单体,以GO/CFGO作为水相添加剂,通过界面聚合(IP)法制备了聚酰胺复合纳滤膜。在此基础上,考察了复合膜的渗透性能,并初步探究了其在染料脱盐浓缩和抗污染中的应用。首先用Hummers法制备了GO,再利用氢溴酸和草酸先后对其进行处理得到CFGO。利用傅立叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)、透射电子显微镜(TEM)对两者的化学结构及形貌进行表征,用接触角考察了两者的亲水性,并用紫外吸收光谱和动态光散射对分散性能进行表征。继而将不同量的GO/CFGO添加到水相溶液中制备得到GO/CFGO复合纳滤膜。采用扫面电镜(SEM)和原子力显微镜(AFM)对膜的表面微观形貌进行表征,傅立叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)对复合纳滤膜的化学结构进行了表征,用接触角测试膜表面亲水性及用Zeta电位仪测量材料的表面电荷。结果表明,CFGO在膜中具有更好的分散性能,并使膜的亲水性更好。在膜的渗透性能实验中,随着GO/CFGO添加量的提高,复合纳滤膜的纯水通量先升高,当GO为0.05%和CFGO烯浓度为0.07%时,GO/PA膜和CFGO/PA膜的纯水通量达到最大值,随后开始下降。实验还研究了复合膜在染料脱盐中的应用,当CFGO的添加量为0.07%时,复合膜的通量达到110.4 L*m-2*h-1,这与复合膜的纯水通量比较接近,显示出CFGO/PA膜在染料脱盐浓缩中广阔的应用前景。最后,探究了复合纳滤膜的抗污染性能。CFGO更能大大提高复合膜的亲水性,降低膜表面粗糙度以及使膜表面带有更多的负电荷,因此CFGO改性后的复合膜的抗污染性能更好。
[Abstract]:Many oxygen-containing functional groups are distributed on the surface of graphene oxide (GOO). These groups make graphene oxide have good dispersion, hydrophilicity, compatibility with polymers, and provide a large number of active sites for further modification. Carboxylated graphene oxide (CFG) has better water solubility and better compatibility with polymers due to the deprotonation of a large number of carboxyl groups on the surface. Polyamide composite nanofiltration membranes were prepared by interfacial polymerization with polysulfone as substrate, piperazine and trimethoyl chloride as monomers and GO/CFGO as water phase additive. On this basis, the permeability of the composite membrane was investigated, and its application in dye desalination concentration and pollution resistance was preliminarily explored. First, GO3 was prepared by Hummers method, and then treated with hydrobromic acid and oxalic acid to obtain CFGO. Their chemical structure and morphology were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM), and their hydrophilicity was investigated by contact angle. The dispersion properties were characterized by UV absorption spectrum and dynamic light scattering. Then the GO/CFGO composite nanofiltration membrane was prepared by adding different amounts of GO/CFGO into aqueous solution. The surface morphology of the composite nanofiltration membrane was characterized by scanning electron microscopy (SEM) and atomic force microscope (AFM). The chemical structure of the composite nanofiltration membrane was characterized by FTIR FTIR and X-ray photoelectron spectroscopy (XPS). The surface hydrophilicity of the film was measured by contact angle and the surface charge of the material was measured by Zeta potentiometer. The results show that CFGO has better dispersibility and better hydrophilicity in the membrane. In the experiment of membrane permeability, the pure water flux of composite nanofiltration membrane first increased with the increase of GO/CFGO addition. When go was 0.05% and CFGO ene concentration was 0.07, the pure water flux of GO-PA membrane and CFGO/PA membrane reached the maximum value, and then decreased. The application of composite membrane in dye desalination was also studied. When the amount of CFGO added was 0.07, the flux of composite membrane reached 110.4 L ~ (-1) m ~ (-2) h ~ (-1), which was close to the pure water flux of composite membrane. It showed that CFGO/PA membrane had a broad application prospect in dye desalination and concentration. Finally, the anti-fouling performance of the composite nanofiltration membrane. CFGO can greatly improve the hydrophilicity of the composite membrane, reduce the surface roughness and make the membrane surface with more negative charge, so the anti-fouling performance of the composite membrane modified by CFGO is better.
【学位授予单位】：浙江工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ051.893

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