The development of superhydrophilic ultrafiltration membrane for oil-water separation

摘要

Membrane process have emerged as one of the most important technologies for high efficient oil-water separation in the field of wastewater treatment.In this work,we report a simple method to prepare polyacrylonitrile (PAN) superhydrophilic ultrafiltration membrane by the combination of hydrolysis and chemical graft technique.The structure and properties of PAN membrane at each modification step was systematically characterized by AFM,SEM,FTIR and drop shape analysis etc.Furthermore,the factors,such as membrane skin-layer porous structure,oil concentration and operation pressure,which could effect on the separation efficiency of superhydrophilic PAN membrane sheet,was evaluated in designed oil-water mixtures.Long-term operation of the membranes was also estimated under different conditions with the purpose of clarifying the anti-fouling properties of the membranes.Our results indicated that the contact angle of PAN membranes modified by hydrolysis and chemical graft technique is lower than 10o.The separation efficiency of superhydrophilic PAN membrane to oil-water mixture could reach 98％,which is closely related to porous structure and oil concentration.The method we reported here is quite facial to prepare high efficient oil-water membrane at large scale,which can well meet with the requirement for practical application.