| Photocatalytic oxidation for drinking water advanced treatment is a technology with bright prospect. In this paper, TiO2 were used as catalyst with irradiation from a ultra-violet germicidal lamp to remove of humic acid (HA) which is important precursor of DBPs in water. At suspended phase, the mechanism and the influencing factors of photocatalytic oxidation of HA were discussed. It shows that the system of photocatalytic oxidation had a higher removal efficiency of HA than that of dark reaction and direct photolysis, arrived to 82.28% of HA, 38.29% of TOC in three hours. The increase of the strength of UV light, initial HA concentration and tempreture, the decrease of initial pH value and extension of irradiation time could all improve the degradation of HA. In addition, there existed an optium dose of catalyst-2g/L. At photocatalytic and ozone oxodation system, the removal efficiency of HA can arrived at 92.75%.On the side, with TiO2 doping Fe3+ prepared by Sol-gel process used for photocatalytic decomposition of HA, the study on the effect of different doing ratio of Fe3+ to TiO2 and baking tempreture show that the optimal ratio of Fe3+to TiO2 is 0.5 %,baking tempreture is 400℃. The removal efficiency of HA with compound catalyst can come to 87.65% in three hours. Photocatalytic oxidation of HA with modifed nanometer TiO2 matched well with the first-order kinetics.On the base of study on degradation of HA in TiO2 aqueous suspension, this paper further investigated the photocatalytic oxidation system of fixed TiO2 film coating on quartz glass tube surface, as well as testing factors of film preparation. That is, catalysis and separation were realized at the same time. These results show the film could successfully oxidize HA, after 3 hours treatment, the removal efficiency of HA reached48.33%.At UV/TiO2/O3 system, it can reached 85.01%. Compared with the suspended phase, the effect is lower.
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