【作者】 曹悦；

【导师】 许振良；

【作者基本信息】 华东理工大学 ， 材料化学工程， 2011， 硕士

【摘要】 本文采用溶胶-凝胶法(sol-gel)分别结合相转化法和高温烧结制备了聚醚砜(PES)-氧化钛(Ti02)复合超滤膜以及氧化铝(Al203)、氧化钛(Ti02)陶瓷中空纤维超滤膜,运用扫描电镜(SEM)、通量、截留率、孔隙率、机械性能等测试方法表征了超滤膜的结构及性能,并从理论出发分析了影响分离膜性能的各项因素。首先,作为前期的基础性研究,采用颗粒法和聚合法分别制备了勃母石溶胶和Ti02溶胶,通过改变溶胶配比及陈化条件研究了影响溶胶性能的各项因素,并为下一步膜制备确定了合适的工艺条件。然后,以钛酸四正丁酯(TBT)为前躯体、二甲基乙酰胺(DMAc)为溶剂制备Ti02溶胶,添加到PES/DMAc/DegOH有机铸膜液体系中,采用浸入相转化法(NIPS)纺制中空纤维复合超滤膜。随着Ti02溶胶含量的增加,铸膜液粘度呈现先降低后升高的变化趋势,并对复合膜微观结构的形成起主导作用。溶胶粒子的加入在一定程度上改善了有机膜的渗透性能,但当TBT含量超过3%以后,聚合物PES大分子对Ti02溶胶粒子的阻隔作用降低,胶粒间发生缩聚反应而聚集,对复合膜各项性能的提高不再起到促进作用。随后,以TBT为前躯体、一缩二乙二醇(DegOH)为溶剂制备Ti02溶胶,添加到PES/DMAc有机铸膜液体系中,采用VIPS-NIPS法刮制复合平板膜。随着Ti02溶胶含量的增加,铸膜液粘度增大,膜的微观结构受动力学影响从指状孔向海绵状孔转变,表面则受热力学影响在Ti02溶胶与溶剂的质量比达到0.5时出现微胞状开口,且渗透通量达到最大。最后,采用浸渍提拉法结合高温烧结在中空纤维状载体上制备了Al203、Ti02超滤膜,其中颗粒型Al203溶胶成膜效果较好,在涂膜三次后即可得到有效膜层,对牛血清蛋白(BAS)溶液的截留率达到90%以上。聚合型Ti02溶胶的成膜效果受溶剂添加量影响较大,溶剂量小焙烧后的膜层易开裂,溶剂量大则达到有效分离所需的涂膜次数就高,大大增加了制膜成本。更多还原

【Abstract】 In this paper polyether sulphone (PES)-titania (TiO2) composite ultrafiltration (UF) membranes were prepared by combination of the sol-gel method and phase separation method. Ceramic (Al2O3、TiO2) hollow fiber UF membranes were prepared by the sol-gel method and then through high heat sintering. The structure and properties of the UF membranes were systemically characterized by various test methods (SEM, flux, rejection, porosity and mechanical properties, etc.). And kinds of factors that effecte the properties of separating membranes were srudied theoretically.Firstly, Al2O3 sol and TiO2 sol were prepared by the Destabilization of Colloidal solution (DSC) and the Polymerization of Molecular Units (PMU) method respectively during the initial basic research period. The factors that effected the properties of the sol were studied with different ratio and aging conditions. And the technologcial conditions were set down for further research.Secondly, TiO2 sol was prepared with Tetrabutyl titanate (TBT) as precursor and dimethyl acetamide (DMAc) as solvent. Then the sol was added to the PES/DMAc/DegOH dopes. The composite hollow fiber UF were prepared by the non-solvent induced phase separation (NIPS) method. The viscosity of the dopes decreased firstly and then increased with the increment of TiO2 sol in dopes. And the microscopic structures of the membranes were mainly depending on the content of the TiO2 sol in the dopes. The addition of the sol particles improved the permeation flux of the membranes when the content of TBT was less than 3%. However, there would be no improvement of the properties of membrans if the content of TBT was more than 3%.Subsequently, TiO2 sol was prepared with TBT as precursor and diethylene glycol (DegOH) as solvent. Then the sol was added to the PES/DMAc dopes. The composite flat membranes were prepared by the VIPS-NIPS method. The dope viscosity increased with the increment of TiO2 sol.Finally, the Al2O3、TiO2 ceramic UF membranes were prepared with hollow fiber carriers by the dipping and drawing method. And the film effect of the granular pattern Al2O3 sol was good. The effective film was made through three times’coating. The rejection of BAS was over 90%. The addition of solvent had great effect on the film effect of the coating times would increase to achieve effective separation if the solvent addition was high, which might result in high cost of production.更多还原