The effect of feed pretreatment on membrane microfiltration of titanium dioxide dispersions by ceramic tubular membranes

Abstract

AbstractThe influence of coagulant type and operating parameters on crossflow microfiltration of aqueous dispersions of titanium dioxide has been examined. The experiments were carried out with a tubular ceramic microfiltration membrane with a nominal pore size of 0.1 μm at various operating parameters. Three chosen types of organic coagulants were used for a series of crossflow microfiltration experiments: polyacrylamide (PAM), poly(diallyldimethylammonium chloride) (PDADMAC), and poly(acrylamide-co-acrylic acid) partial sodium salt (PACA). The value of steady-state permeate flux has been experimentally evaluated for the crossflow microfiltration with and without pretreatment. The results of the experiments without coagulants showed that the flux initially declines rapidly and then stabilizes. The results also suggested that PDADMAC was a better coagulant for this system and its optimal concentration was 30 mg l−1. Finally, it was shown that pretreatment of the feed by PDADMAC resulted in a permeate flux...