Determination of hydroxyl radicals in TiO_2/Ti photoelectrocatalytic oxidation system using Fe(phen)_3^{2+} spectrophotometry

Article type: Research Article

Authors: JIANG, Yan-li^{; ;} | LIU, Hui-ling | WANG, Qun-hui | JIANG, Zhao-hua

Affiliations: Department of Environmental Engineering, Harbin Institute of Technology, Harbin, 150001, China | Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001, China | School of Life Science and Chemistry, Harbin University, Harbin 150086, China

Note: [] Corresponding author. E-mail: [email protected]

Abstract: A new method of determining the cumulate concentration of hydroxyl radicals in the TiO_2/Ti photoelectrocatalytic (PEC) oxidation system was established by o-phenanthroline-Fe(II)(Fe(phen)_3^{2+}) spectrophotometry and using anion exchange membrane. Fe (phen)_3^{2+} can be oxidized to o-phenanthroline-Fe(III)(Fe(phen)_3^{3+}) by strong oxidization of hydroxyl radicals (·OH). Then the cumulate concentration of hydroxyl radicals can be calculated through determining the change of the Fe(phen)_3^{3+} absorbency at 509 nm. In addition, the research results showed the production rate of hydroxyl radicals was affected obviously by pH of solution, the cumulate concentration of hydroxyl radicals was the largest at nearby the initial pH 6.3 (isoelectric point), and the change direction of pH after illumination tended to nearby isoelectric point.

Keywords: TiO[TeX:] _2/Ti catalyst, photoelectrocatalysis, o-phenanthroline-Fe, hydroxyl radical, anion exchange membrane

Journal: Journal of Environmental Sciences, vol. 18, no. 1, pp. 158-161, 2006