Abstract
CA/CS/TiO2 composite membranes were formed by cellulose acetate (CA) electrospun fibers which were used as the basal layer, and chitosan (CS)/sol-gel titanium dioxide (TiO2) which was coated as a surface layer on one side. The composite membrane exhibited a smooth and flat surface when the CS:TiO2 ratio was 10:1 (mass ratio) and the CA:CS ratio was 12:10 (volume ratio). This layered structure of the membrane exhibited a water flux of 119 L/(m2·h). Adsorption testing of this composite membrane for dyes showed that the adsorption capacities of methylene blue and rhodamine were 42 and 51 mg/g, respectively. The composite membrane showed better adsorption performance for rhodamine mainly because of the bonding between the hydroxyl groups of CS and TiO2 and the carboxyl groups of the rhodamine dye. The adsorption processes of the two dyes were in accord with a second-order kinetic equation.