酪蛋白的聚集态及其膜分离

Casein aggregation states and membrane separation

采用孔径分别为50、200和500 nm的陶瓷膜处理碱性酪蛋白水溶液,考察操作条件及pH对过滤通量和截留率的影响,并研究酪蛋白胶束在不同pH下的聚集行为。结果表明:采用孔径为200 nm的陶瓷膜过滤1 g/L的酪蛋白溶液,在pH=13,操作压差0.10 MPa,膜面流速3.0 m/s条件下,可获得膜通量266 L/(m2·h)和酪蛋白截留率71.8%,综合效果好。酪蛋白的胶束尺寸和黏度随pH的增大而增大。膜过滤通量随pH增大而减小;截留率随pH增大而增大。

Ceramic membranes with pore sizes of 50,200 and 500 nm were used to remove casein from its alkaline solution.The effects of the operation conditions and pH on the membrane flux and rejection were investigated.The aggregation behavior of casein micelle with different pH was also studied.By using the membrane with pore size of 200 nm to filtrate the 1 g/L casein solution,a flux of 266 L/（m2·h） and a rejection of 71.8% were achieved at pH=13,the trans-membrane pressure of 0.10 MPa,and the cross flow rate of 3.0 m/s.The pore size of 200 nm was best in the investigation.The casein micelle size and the solution viscosity increased with the increase of pH.As the solution pH increased,the membrane flux decreased while the increase of the rejection.