| Phaeocystis globosa Scherffel,one of the harmful algae bloom causing species,had frequently caused red tide in the world and brought huge damage recent years.The nano-TiO2 photocatcalisis technologe has showed great ability of removal freshwater algae like Cyanophytes and Cladophora.Utilize those work,A research on removing Phaeocystis globosa Scherffel by TiO2 and Fe(Ⅲ)-TiO2 photocatalyst was made.TiO2 has good ability on removal Phaeocystis globosa under UV light,without obvious removal ability under visible light.Fe(Ⅲ)-TiO2 has good ability on removal Phaeocystis globosa under both UV light and visible light.The effection of algae removal can be raised by raise of dissolved oxygen in water and surface area,dispersion degree and dosages of photocatalyst.The contents of Fe(Ⅲ) can also effect the algae removal.The Fe(Ⅲ)-TiO2 work best when the ratio of nFe:nTiO2 is 1:100.By use of Fe(Ⅲ)-TiO2 made in laboratory,the Phaeocystis globosa can be removal effectively in 48 h.The color of algae water changed from cloudy claybank to transparent and colourless.Chl-a reduced to 0.001 mg·L-1 from 6.66 mg·L-1.The cell density reduced to 0.01×105 cell·mL-1 from 6.48×106 cell·mL-1.The removal rate up to 99.9%.The mechanism of algae removal was preliminary deduced as that the Fe(Ⅲ)-TiO2 was excitated by light and produced e--h+.Those e--h+ reacted with O2 and H2O and produced a mass of active·OH,which can destroy epicyte and ultimately kill the cells of Phaeocystis globosa.
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