【作者】 杨超；

【导师】 刘琨；

【作者基本信息】 广西大学 ， 化学工艺， 2008， 硕士

【摘要】 聚醚共聚乙酰胺（PEBA）是一种廉价易得的高分子材料,由它制成的渗透汽化膜对挥发性有机物具有良好的选择性渗透能力。通过红外光谱和元素分析了解PEBAx2533共聚物的化学组成结构;采用溶液浇铸法制备PEBA均质膜,并应用DSC-7差热扫描量热仪测定膜的热稳定性;通过拉伸性能试验,测定了膜机械性能。结果显示膜具有较好的热稳定性和机械强度。通过溶胀实验,分别测定了膜在正丁醇、醋酸正丁酯、醋酸以及它们水溶液中的溶胀度,考察了浸泡时间、温度及溶液浓度对溶胀度的影响。结果表明膜在醋酸正丁酯中的溶胀度最大,在水中的溶胀度最低;膜在上述各液体中浸泡,2min基本达到平衡;膜溶胀度随浓度和温度增加而升高。利用摩尔引力常数和基团贡献法计算了膜的溶解度参数,它们与正丁醇和醋酸正丁酯的溶解度参数较接近,而与水的溶解度参数相差较大,由此可以解释该膜对醋酸正丁酯较好的溶解性能。还分别采用Flory-Huggins和UNIQUAC模型预测了水/正丁醇、水/醋酸正丁酯及水/醋酸二元混合液在膜中的溶解度。其中用溶解度参数法得到Flory-Huggins模型中的相互作用参数;用正丁醇、醋酸正丁酯、醋酸与膜的溶胀数据拟合得到UNIQUAC模型中溶剂与膜的二元相互作用参数。预测结果表明液相有机物含量增大,溶解在膜中的有机物含量就越多。对于以下四种化合物的吸附顺序是:醋酸正丁酯＞正丁醇＞醋酸＞水。两种模型的计算结果基本一致,结果也表明PEBA膜是一种良好的亲有机物膜。通过渗透汽化实验,分别分离醋酸正丁酯和正丁醇水溶液中的微量醋酸正丁酯和正丁醇。探讨了浓度和温度对渗透通量和分离因子的影响,膜对醋酸正丁酯的分离效果比对正丁醇的分离效果好;渗透通量和分离因子都随着醋酸正丁酯浓度的增加而增加;渗透通量随着温度的升高而增加。分离因子随温度的升高而减小。当浓度为到0.6%时,醋酸正丁酯的渗透通量为143.9(g·m^-2·h^-1),分离因子可达236.9。更多还原

【Abstract】 Poly-ether block amide （PEBA） is one of cheap and getting for easy macromolecule material. The Pervaporation membrane made of it has a nice selectivity for volatility organics. The chemical structure of PEBAx2533 was conformed by infrared spectrum and element analysis. The PEBA homogeneous membrane was prepared by solvent casting. The heat stability of membrane was determined also by DSC-7. The tensile performance of membrane was tested by GB/T10140-9. The results show it has better heat stability and machine intensity. The membrane’s swelling behavior in N-butyl acetate, n-butanol, acetic acid and their solution was explored, respectively by swelling tests. The influence of time and temperature as well as liquid concentration on swelling degree was investigated yet. There is the best swelling degree in N-butyl acetate, meanwhile the least in water. The swelling equilibrium was basically achieved after 2 min. The swelling degree increased along with the raise of concentration and temperature.The solubility parameters of membrane were calculated by the method of group contribution and constant of mol gravitation basing on the theory of solubility parameters. The results are closed to them of n-butyl acetate and n-butanol, moreover far away it of water. The solubility of water/organic binary mixtures in the membrane was forecasted with Flory-Huggins and UNIQUAC model respectively. The interaction parameters of the Flory-Huggins have been determined on the theory of solubility parameters. In addition, the interact parameters of solvents and membrane in UNIQUAC model were determined by the data fit of the swelling data. The organics content in the membrane are more and more its content in the liquid mixtures. Its selectivity absorbtion follows the order of n-butyl acetate > n-butanol > acetic acid>water. The calculation results are basic coincident between the Flory-Huggins and UNIQUAC model. This show that the PEBA membrane preferentially absorbtion the organics over water. The results further showed that PEBA is one of good hydrophobic materials.The membrane was used in removal of minim N-butyl acetate and n-butanol from their aqueous solution by pervaporation experiments. The effects of concentration and temperature on the permeation flux and separation factor were studied. The separation impact of N-butyl acetate was better than that of n-butanol. The flux and separation factor increased with N-butyl acetate concentration. The flux increased with temperature, but the separation factor decreased with temperature. The separation factor was 143.9(g·m^-2·h^-1) and 236.9 of N-butyl acetate, respectively, when its concentration to be 0.6 %（w/w）.更多还原