Determination of Hydroperoxyl/superoxide Anion Radical (HO2¤ý/O2¤ý-) Concentration in the Decomposition of Ozone Using a Kinetic Method

Bulletin of the Korean chemical society

Jai H. Lee¹  Bum Gun Kwon¹ 

关键词: Hydroperoxyl radical;    Superoxide anion radical;    Ozone;    Fenton-like;    Hydroxyl radical;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

A novel kinetic method for determination of HO₂^·/O₂^·- in ozone decomposition in water is described. In this study, potential interferences of O₃ and the hydroxyl radicals, ·OH_(O3), are suppressed by HSO₃^-/SO₃^2-. HO₂^·/O₂^·- formed in ozone decomposition reduces Fe³⁺-EDTA into Fe²⁺-EDTA and subsequently the well-known Fenton-like (FL) reaction of H₂O₂ and Fe²⁺-EDTA produces the hydroxyl radicals, ·OH_(FL). Benzoic acid (BA) scavenges ·OH_(FL) to produce OHBA, which are analyzed by fluorescence detection (ルex = 320 nm and ルem = 400 nm). The concentration of HO₂^·/O₂^·- in ozone decomposition has been determined by the novel kinetic method using the experimentally determined half-life (t_1/2). The steady-state concentration of HO₂^·/O₂^·- is proportional to the O₃ concentration at a given pH. However, the steady-state concentration of HO₂^·/O₂^·- in ozone decomposition is inversely proportional to pH values. This pH dependence is due to significant loss of O₂^·- by O₃ at higher pH conditions. The steady-state concentrations of HO₂^·/O₂^·- are in the range of 2.49 (�? 0.10) �? 10^-9 M (pH = 4.17) ~ 3.01 (�? 0.07) �? 10^-10 M (pH = 7.59) at [O₃]_o = 60 レM.

【 授权许可】

Unknown