聚丙烯酸钠复合超滤膜研制初探 (Ⅰ)UPANA-1复合膜的制备

Primary study of preparation of polyacrylic sodium composite ultrafiltration membrane (Ⅰ) Preparation of UPANA-1 composite membrane

以聚丙烯酸钠为复合膜分离层材料 ,多孔的聚醚砜 (PES)超滤膜为基膜研制出具有超薄分离层的聚丙烯酸钠复合超滤膜 (UPANA - 1) .用浓度为 0 .0 0 5 g/L的分子量为 10 0 0的聚乙二醇水溶液作为介质溶液 ,室温、压力 0 .6MPa下做膜性能测试 ,UPANA - 1膜的截留率大于 90 % ,水通量为 32 .6L/ (m2 ·h) .并着重研究了基膜的选择、超薄分离层膜液的组成等制膜条件对复合膜性能的影响 .

The polyacrylic sodium composite ultrafiltration membrane(UPANA-1) was prepared by coating an asymmetric PES substrate ultrafiltration membrane (MWCO=70 000) with the solution of polyacrylic sodium. UPANA-1 membranes were tested at room temperature and under the pressure of 0.6 MPa with the mass concentration of 0.005 g/L PEG ( M w=1 000) solution,a flux of 32.6 L/(m 2·h) and a rejection of 92.2% were obtained. Studies on the effects of membrane making conditions, such as concentration of polyacrylic sodium, glycerol, the mass radio of glycerol and HCl, acetic acid and methanol as well as substrate membrane and the clearance of stroll scraper on membrane properties were carried out. The results follow : (1) materials of substrate affect composite membrane performance, PES-700 ultrafiltration membrane with MWCO 70 000 was the best choice. (2) the concentration of polyacrylic sodium in casting solution was one of the important parameters affecting membrane properties .When the weight of of polyacrylic sodium added into the coating solution was 0.19 g,the best separation performance of membrane was obtained.(3)addition of glycerol contributed to improve the selectivity of composite membrane much more compared with glycerol and PEG-400.(4)when the mass radio of glycerol and HCl was 3∶2, composite membrane performance was perfect.(5)addition of 3 mL acetic acid and 2 mL methanol is favorable to improve the flux of composite membrane.(6) when there was a clearance of 40 μm between the scraper and the surface of substrate, the thickness of skin layer was most suitable.