title: Photodecomposition of humic acid and natural organic matter in swamp water using a TiO(2)-coated ceramic foam filter: potential for the formation of disinfection byproducts.
abstract: This paper reports on the photodecomposition of aqueous humic acid (HA) by a TiO(2)-coated ceramic foam filter (TCF) reactor and on the potential for the formation of disinfection byproducts (DBPs) upon chlorination of the photocatalytically treated solutions. This photocatalytic reactor can also be applied to the removal of natural organic matter (NOM) in swamp waters. The proposed photocatalytic reaction system was operated as per standardized methodologies. First, the ability of the TCF to decompose HA (a representative compound of NOM) was evaluated from the changes in the total organic carbon (TOC) and UV(254) with the reaction time. Remarkably, TOC removal and UV(254) values ranging from 44% to 61% and from 60% to 83%, respectively, were achieved. The potential for the formation of DBPs (total trihalomethane and total haloacetic acid) by chlorination of the phototreated solution was strongly dependent on the TOC removal and UV(254) values in the solution. The degree of photodecomposition of NOMs in the swamp water samples and the DBP formation potential showed similar trends as in the case of the standard solutions containing HA. The method used in this study could be effectively used to evaluate the efficiency of TCF for reducing HA and NOM, while suppressing the formation of DBP products.
authors.affiliation: Department of Chemistry and Chemical Biology, Graduate School of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan. mori@gunma-u.ac.jp
authors.forename: Masanobu
authors.initials: M
authors.lastname: Mori
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Sugita
authors.forename: Akinori
authors.initials: A
authors.lastname: Mase
authors.forename: Takahiro
authors.initials: T
authors.lastname: Funatogawa
authors.forename: Masaru
authors.initials: M
authors.lastname: Kikuchi
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Aizawa
authors.forename: Shigekazu
authors.initials: S
authors.lastname: Kato
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Saito
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Ito
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Itabashi
mesh_terms: D004202:Disinfectants / Q000032:analysis* / Q000737:chemistry; D005374:Filtration; D006812:Humic Substances / Q000032:analysis*; D055668:Photochemical Processes; D014025:Titanium / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry; D018508:Water Purification / Q000379:methods*; D053833:Wetlands
chemical_list: D004202:Disinfectants; D006812:Humic Substances; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D014025:Titanium