【作者】 任晓晶；

【导师】 皇甫风云；

【作者基本信息】 天津工业大学 ， 应用化学， 2007， 硕士

【摘要】 芳香聚酰胺作为一种合成高分子材料，以其特有的分子结构在膜的热稳定性及化学稳定性方面，明显优于醋酸纤维素等其它膜。研制并开发芳香聚酰胺纳滤膜，可以为我国水净化及环保领域提供新的膜品种，具有一定的现实意义。本文所用的芳香聚酰胺是聚间苯二甲酰间苯二胺（PMIA），并采用该种膜材料，用相转化法制备了平板纳滤膜，用干-湿法制备了中空纤维纳滤膜。制备过程中影响纳滤膜性能的因素是多方面的，着重讨论了聚合物浓度、添加剂含量、溶剂挥发时间、凝胶浴组成和温度、膜厚等的影响；采用正交试验法对制备条件进行优化，确定出最佳制膜工艺，得到了性能良好的芳香聚酰胺平板纳滤膜。本文在芳香聚酰胺平板纳滤膜研制的基础上，采用干—湿法纺丝制膜技术，纺制了芳香聚酰胺中空纤维纳滤膜。考察了纺丝溶液流动性、喷丝头温度、蒸发距离和后处理等制膜工艺参数对纳滤膜成型及性能的影响，摸索最佳的制膜工艺。用扫描电子显微镜观察膜的微观结构。详细讨论了纳滤膜的分离特性，并对膜分离过程中一些操作因素的影响进行了研究。实验结果表明，所制芳香聚酰胺纳滤膜对二价和高价无机盐离子及有机小分子物具有较好的选择分离性能。该膜在25℃，操作压力为0.5MPa时，对500mg／L的MgSO₄的脱盐率为27.43％，对500mg／L的Na₂SO₄的脱盐率为30.10％，对800mg／LPEG-1000的截留率为67.28％。该膜具有很好的耐溶剂性和抗污染性。更多还原

【Abstract】 As a synthesize macromolecule material, aromatic polyamide has better thermic and chemic stability than cellulose acetate and other kinds of materials for membrane preparing ,owning to its special molecular structure .It is practical and meaningful to develop the aromatic polyamide nanofiltration（NF） membranes. This can not only exactly fills the gap between ultrafiltration（UF） and reverse osmosis, but also provides a new kind of membrane.The aromatic polyamide used in this study is polyisophthaloyl metaphenylene diamine.In this work, flat nanofiltration（NF） membrane with small molecular weight cut-off （MWCO）was successfully prepared by means of Phaseinversion method, with aromatic polyamide as raw material and dimethylacetamide（DMAc）as solvent. The effects of aromatic polyamide concentration in the casting solution, the concentration of the additive in the casting solution ,the evaporation time of nascent membrane, the temperature and composition of coagulation bath and the thickness of membranes on the performance of nanofiltration （NF ）membranes were investigated .Aromatic polyamide hollow fiber nanofiltration membrane was studied by means of dry-wet spinning on the bases of flat nanofiltration（NF） membrane. The properties of membrane and the parameters of spinning technology are affected by the fluidity of spinning solution , spinneret’s temperature, vaporing distance pressure of internal liquid and latter treatment. Based on the discussing of above ingredients ,a optimal spinning technology was found .Microstructure prepared membrane was analysed by Scanning Electron Microscopy（SEM）.The separation performance of prepared membrane and some operating factors were mainly discussed.The results show that ,at 25℃,0.5MPa ,the rejection ratio of 500mg /L MgSO₄ solution is 27.43%, the rejection ratio of 500mg/L Na₂SO₄ solution is 30.10%.The membrane prepared showed a good PEG-1000 rejection rate up to 67.28 % .The nanofiltration membrane has better resistance to organic solutes and contamination.更多还原