Abstract: The effects of imidization method，coagulation bath and temperature were studied on the structure and separation performance of polyimide membrane，prepared by using pyromellitic dianhidride and 4,4′-oxydianiline as raw materials. The optimal synthesis conditions of polyimide membranes were as follows：15%(wt) polyamide casting solution，the coagulation bath was 30 %(wt) ethanol aqueous solution, chemical imidization at room temperature for 48 h. The synthesized polyimide membrane showed good nanofiltration performance for organic mixtures of lubricant oil with acetone and benzene solvents. The rejection rate was 66% and the flux was 4.26 L/(m2·h).under the steady-state operation with an operation pressure of 2 MPa. These results are important to developing commercial nanofiltration membrane for organic solvent mixtures.

摘要： 针对以均苯四甲酸二酐(PMDA)和4, 4′-二氨基二苯醚（ODA）为原料合成聚酰亚胺的过程，研究了亚胺化方法、凝胶浴组成与温度等条件对膜的结构和分离性能的影响。实验结果表明，当聚酰胺酸铸膜液质量分数为15％、凝胶浴为30％乙醇（质量）的醇水溶液时，所制得的聚酰亚胺纳滤膜具有最佳的分离性能。操作压力为2 MPa下稳态操作时，该膜对酮苯脱蜡工艺后的溶剂与润滑油基础油混合物的截留率达66％，通量为4.26 L/（m2·h），为有机溶剂体系的纳滤膜分离技术的工业应用提供了基础。