title: Effects of UV irradiation on humic acid removal by ozonation, Fenton and Fe⁰/air treatment: THMFP and biotoxicity evaluation.
abstract: Effects of UV irradiation on humic acid (HA) removal by Fe(0)/air, ozonation and Fenton oxidation were investigated. The trihalomethane forming potential (THMFP) and toxicity of treated solutions were also evaluated. The experimental conditions were ozone of 21 mg min(-1), H(2)O(2) of 8 × 10(-4)M, Fe(0) of 20 g L(-1), air flow of 5 L min(-1), and UVC of 9 W. Results indicated that Fe(0)/air rapidly removed HA color (>99%) and COD (90%) within 9 min. 51-81% of color and 43-50% of COD were removed by ozonation and Fenton oxidation after 60 min. Both UV enhanced ozone and Fenton oxidation removed HA, but the Fe(0)/air process did not. Spectrum results showed all processes effectively diminished UV-vis spectra, except for ozonation. The THMFP of Fe(0)/air-treated solution (114 μg L(-1)) was much lower than those of Fenton- (226 μg L(-1)) and ozonation-treated solutions (499 μg L(-1)). Fe(0)/air with UV irradiation obviously increased the THMFP of treated solution (502 μg L(-1)). The toxicity results obtained from Vibrio fischeri light inhibition test indicated that the toxicity of Fe(0)/air-treated solution (5%) was much lower than that of ozonation- (33%) and Fenton-treated solutions (31%). Chlorination increased the solution toxicity. The correlation between biotoxicity and chloroform in the chlorinated solution was insignificant.
authors: Department of Food Science, Central Taiwan University of Science and Technology, Taichung, Taiwan, ROC.
authors: Ming-Chi
authors: MC
authors: Wei
authors: Kai-sung
authors: KS
authors: Wang
authors: Tung-En
authors: TE
authors: Hsiao
authors: I-Chen
authors: IC
authors: Lin
authors: Hui-Ju
authors: HJ
authors: Wu
authors: Yuh-Luan
authors: YL
authors: Wu
authors: Pey-Horng
authors: PH
authors: Liu
authors: Shih-Hsien
authors: SH
authors: Chang
mesh_terms: D000388:Air; D048908:Aliivibrio fischeri / Q000187:drug effects*; D006812:Humic Substances; D007501:Iron / Q000737:chemistry*; D010126:Ozone / Q000737:chemistry*; D022882:Trihalomethanes / Q000138:chemical synthesis* / Q000633:toxicity; D014466:Ultraviolet Rays
chemical_list: D006812:Humic Substances; D022882:Trihalomethanes; D010126:Ozone; D007501:Iron