Drinking water treatment in a gravimetric flow system with TiO2 coated membranes

This paper presents filtration results for drinking water treatment obtained with a commercial cellulose acetate membrane of 0.45 μm pore diameter, with and without TiO2 coating. The deposition of titanium dioxide thin films onto membrane surface was made by pulsed-frequency d.c. reactive magnetron sputtering at room temperature from a high purity Ti target in Ar/O2/N2 atmosphere, at different conditions for cathode current and for deposition time. The proposed membranes were used in a filtration system driven by gravitation without the requirement of energy supply. The obtained results showed that the proposed system is able to remove color and turbidity from raw water. Besides, the modified membrane presented better results than the neat one regarding to membrane fouling and chlorine removal.

► Modification of the membrane surface by titanium dioxide coatings. ► Application of a gravitational system without requirement of energy supply. ► The proposed system is suitable for water treatment. ► Coated membranes showed superior results for turbidity and free chlorine removals.