臭氧预处理蛋白质对聚醚砜超滤膜污染行为的影响研究

Effect of ozonation on the protein fouling of polyethersulfone ultrafiltration membranes

本研究选用牛血清蛋白(BSA)代表超滤膜典型污染物,通过考察臭氧预处理前后污染层结构特征、污染物在膜面吸附累积及作用力变化特征,结合宏观膜污染行为,解析臭氧预处理对不同孔径超滤膜BSA污染行为的影响机制.结果表明,臭氧预处理后,无论BSA尺寸大于、小于或接近膜孔尺寸,膜污染速率以及不可逆污染幅度皆明显加剧,说明臭氧氧化对污染物与膜孔相对尺寸的影响并不是其影响膜污染行为的关键因素,而臭氧预处理加剧膜污染的根本原因是其促进了BSA分子间二硫键的形成.臭氧预处理后,共价二硫键的形成有效掩盖了静电作用力、氢键及疏水力的变化,促进了BSA在膜面的吸附累积,并形成致密无孔的污染层,最终引起较为严重的膜污染.

In this study,bovine serum protein(BSA)was selected to represent the typical organic foulants of ultrafiltration membranes.Before and after pre-ozonation,the fouling layer structure,the adsorption behavior of foulants onto membrane surface and the interaction force of foulants at membrane surface were investigated.All these were combined with the results of macro membrane fouling behavior to unravel the influence mechanism of pre-ozonation on the protein fouling of ultrafiltration membranes with different pore size.