PEO亲水型聚酰胺纳滤膜制备与研究

发布时间：2018-06-04 23:40

本文选题：纳滤 + PEO　；参考：《天津工业大学》2017年硕士论文

【摘要】：纳滤(nanofiltration,NF)作为一种压力驱动膜过程,近几十年受到人们广泛关注。但是膜污染尤其是不可逆污染严重限制纳滤膜的应用,而抗污染膜的制备是解决膜污染的关键。含有醚键的亲水性材料以其独有的抗污染特性被广泛应用于膜分离领域,本文具体的研究内容及结果如下。以聚砜(PSf)作为支撑膜材料,以O,O'-二(2-氨基丙基)聚丙二醇-嵌段-聚乙二醇-嵌段-聚丙二醇(Jeffamine)和均苯三甲酰氯(TMC)分别作为水相、油相反应单体,界面聚合合成Jeffamine-TMC复合膜。通过傅里叶红外(FTIR)、X射线光电子能谱(XPS)、扫描电镜(SEM)、接触角等测试对膜进行了表征,并探索Jeffamine分子量、水相pH、反应时间、水/油相浓度、后处理包括加热时间和加热温度等因素对复合膜渗透分离性能的影响。在一定条件下,复合膜对硫酸镁截留率达到45%,通量50 L/m2/h,分离性能还有待提高,通过牛血清蛋白(BSA)和腐殖酸(HA)污染测试,发现抗污染效果不佳。为了提高复合膜分离效果,改变聚砜基膜质量分数,探索基膜对Jeffamine-TMC渗透分离性能影响,另一方面,在界面聚合水相单体中掺入其他类型水相单体,哌嗪、间苯二胺及三(2-氨基乙基)胺三种单体,得到Jeff/PIP-TMC、Jeff/MPD-TMC 及 Jeff/TAEA-TMC 复合膜,可以发现,对于三种复合膜Jeffamine相对含量的降低都会引起复合膜分离性能的提高,通量的减少。为提高抗污性能,利用初生态复合膜膜表面未反应的酰氯基团以及水解生成的羧基基团,二次界面聚合构建双层PEO结构。界面聚合后复合膜表面形态发生变化,粗糙度增加,Zeta电位测试及静态水接触角测试表明PEO活性层负电荷性减弱、亲水性能提高,截留和污染实验表明二次界面聚合对复合膜渗透分离性能影响不大,提高了复合膜的抗污染性能。
[Abstract]:Nanofiltration NF (NF) as a pressure-driven membrane process has attracted much attention in recent decades. However, membrane fouling, especially irreversible fouling, severely limits the application of nanofiltration membrane, and the preparation of antifouling membrane is the key to solve membrane fouling. Hydrophilic materials containing ether bonds are widely used in membrane separation due to their unique antifouling properties. The specific research contents and results are as follows. The Jeffamine-TMC composite membranes were synthesized by interfacial polymerization of polysulfone (PSF) as the supporting membrane material, and the Jeffamine-TMC composite membranes were synthesized by interfacial polymerization, respectively, using the polypropanediol-block-poly (ethylene glycol)-block-poly (propylene glycol)-Jeffamine- poly (propylene glycol) and tribenzoyl chloride (TMC) as the water phase and the oil phase reactive monomers, respectively. The films were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and contact angle. The molecular weight of Jeffamine, pH of water phase, reaction time and concentration of water / oil phase were investigated. The effects of heating time and heating temperature on the permeation performance of the composite membrane were studied. Under certain conditions, the retention rate of magnesium sulfate reached 45%, the flux was 50 L / m ~ 2 / h, and the separation performance still needed to be improved. Through the tests of bovine serum protein (BSA) and humic acid (HA) pollution, it was found that the anti-pollution effect was not good. In order to improve the separation effect of composite membrane, change the mass fraction of polysulfone base membrane and explore the effect of base membrane on the permeability separation of Jeffamine-TMC, on the other hand, other kinds of aqueous monomer, piperazine, were added into the interfacial polymerized aqueous monomer. Jeff / PIP-TMC / Jeff / MPD-TMC and Jeff/TAEA-TMC composite membranes were obtained from three monomers of m-phenylenediamine and tri-2-aminoethyl) amine. It was found that the decrease of relative content of Jeffamine in the three kinds of composite membranes would increase the separation performance and decrease the flux of the composite membranes. In order to improve the anti-fouling property, the two-layer PEO structure was prepared by secondary interfacial polymerization using unreacted acyl chloride groups and carboxyl groups generated by hydrolysis on the surface of the primary ecological composite membrane. After interfacial polymerization, the surface morphology of the composite film changed, the roughness increased, the Zeta potential and the static water contact angle test showed that the negative charge of the PEO active layer was weakened, and the hydrophilicity of the active layer was improved. The retention and fouling experiments showed that the secondary interfacial polymerization had little effect on the permeation and separation performance of the composite membrane, and the anti-fouling performance of the composite membrane was improved.
【学位授予单位】：天津工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ051.893

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