Abstract: The degradation of fulvic acid (FA) by nanoparticle TiO2 in a
submerged membrane photocatalysis (SMPC) reactor was studied. In this reactor,
photocatalytic oxidation and membrane separation co-occured. The continuous air
supplier provided O_2 for the photocatalytical reaction and
mixed the solution through an airflow controller. The particle
TiO_2 could automatically settle due to gravity without
particle agglomeration so it could be easily separated by microfiltration (MF)
membrane. It was efficient to maintain high flux of membranes. The effects of
operational parameters on the photocatalytic oxidation rate of FA were
investigated. Results indicated that photocatalyst at 0.5 g/L and airflow at
0.06 m^3/h were the optimum condition for the removal of
fulvic acid, the removal efficiency was higher in acid media than that in
alkaline media. The effects of different filtration duration on permeate flux
rate of MF with P25 powder and with nanoparticle TiO_2 were
compared. Experimental results indicated that the permeate flux rate of MF was
improved and the membrane fouling phenomenon was reduced with the addition of
nanoparticle TiO_2 catalyst compared with conventional P25
powder. Therefore, this submerged membrane photocatalysis reactor can faciliate
potential application of photocatalytic oxidation process in drinking water
treatment.