Characterisation of membrane prepared from cellulose acetate and polyguanidine

Abstract

In this study, membranes were prepared from hydrophilic cellulose acetate (CA) and antibacterial polyhexamethylene guanidine hydrochloride (PHMG) by phase inversion method to improve membrane separation and antifouling capacities. The influence of preparation conditions on membrane structure and separation performance has been investigated and evaluated. The experimental results indicated that the CA membranes prepared by the phase inversion method have an asymmetric structure with a dense top layer located onto a porous supporting layer. The concentration of CA in casting solution highly influences membrane structure and its separation capacity. When the CA concentration increased from 12.2 to 18.2%, at a filter pressure of 5 bar, the prepared membrane flux gradually decreased from 46.47 to 38.72 l/m2.h due to the increase in membrane surface thickness. In comparison with the pure CA membrane, the CA/PHMG membranes have higher average filtration yield (1.6 times), lower degree of membrane fouling, and much better antifouling properties.