title: Oxidation and decomposition kinetics of thiourea oxides.
abstract: In this report the decomposition and oxidation kinetics of thiourea dioxide and thiourea trioxide are investigated with a reversed-phase ion-pair high-performance liquid chromatography (HPLC) method. The HPLC method allows us to simultaneously determine and quantify several sulfur-containing reagents such as (NH2)2CSO2, (NH2)2CSO3, (NH2)2CO, and SO3(2-) (HSO3-). Experiments illustrate that the decomposition of thiourea oxides is a first-order reaction, in which the rate constants increase with the pH of the solution. Oxidations of thiourea oxides by hydrogen peroxide are first order with respect to both reagents within the studied pH range between 4.0 and 8.0. Oxidation rate constants are measured under different pH conditions, which show that increasing the pH of the reaction solution significantly accelerates the oxidation process.
authors.affiliation: College of Chemical Engineering, China University of Mining and Technology, Xuzhou, Jiangsu Province 221008, People's Republic of China. gaoqy@cumt.edu.cn
authors.forename: Qingyu
authors.initials: Q
authors.lastname: Gao
authors.forename: Bing
authors.initials: B
authors.lastname: Liu
authors.forename: Lianhe
authors.initials: L
authors.lastname: Li
authors.forename: Jichang
authors.initials: J
authors.lastname: Wang
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013890:Thiourea / Q000737:chemistry*; D013997:Time Factors
chemical_list: D010087:Oxides; D006861:Hydrogen Peroxide; D013890:Thiourea