海藻酸钙水凝胶过滤膜的制备及其对硫酸钙的截留

摘要

以尿素为致孔剂制备了海藻酸钙(CA)水凝胶过滤膜，测试了其通量、截留率和力学性能；通过扫描电子显微镜(SEM)观测其过滤硫酸钙前后的表面形貌.结果表明，增加尿素含量，均导致膜应力和应变的下降；而膜的纯水通量则迅速增大，尿素含量为3．0％(质量分数)时达到28．7 L/(m2·h)，为最大；0．2 MPa下，过滤1．7 g/L 硫酸钙时对 Ca2＋和 SO 2－4的截留率分别为83％和92％，稳定通量达到21．7 L/(m2·h).%In this thesis,urea was used as a porogen to prepare calcium alginate (CA)hydrogel filtration mem-brane.The flux,retention and mechanical properties of the CA filtration membrane were tested.The surface morphology of CA filtration membrane before and after filtrating calcium sulphate was observed by scanning e-lectron microscopy (SEM).Results showed that the stress and strain of the membrane reduced with the increase of urea content.When the concentration of urea was less than 2.5wt%,the water flux of membrane increased rapidly with the increase of urea content.When the urea was 3.0wt%,the flux reached 28.7 L/(m2 ·h).With the continue increase of the urea amount the flux increased little.When the pressure was fixed at 0.2 MPa,the retention rate of Ca2 + and SO 2 -4 for the CA filtration membrane was 83% and 92%,respectively.And the stable flux reached 21.7 L/(m2 ·h).