KINETICS AND MECHANISM OF THE CHLORITE THIOUREA REACTION IN ACIDIC MEDIUM

被引：66

作者：

EPSTEIN, IR ^{[1
]}

KUSTIN, K ^{[1
]}

SIMOYI, RH ^{[1
]}

机构：

[1] W VIRGINIA UNIV, DEPT CHEM, MORGANTOWN, WV 26506 USA

来源：

JOURNAL OF PHYSICAL CHEMISTRY | 1992年 / 96卷 / 14期

关键词：

D O I：

10.1021/j100193a039

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The kinetics of the reaction between chlorite and thiourea in acidic medium have been studied. The stoichiometry of the reaction for pH > 3 is 2ClO2- + SC(NH2)2 + H2O --> 2Cl- + OC(NH2)2 + SO42- + 2H+; for pH < 3 OC(NH2)2 is hydrolyzed to NH4+ and CO2. The reaction is characterized by an induction period after which chlorine dioxide is produced. For [ClO2-]/[SC(NH2)2] < 2 the formation of chlorine dioxide is only transient. Thiourea is progressively oxidized to sulfonic acid before cleavage of the sulfur-carbon bond and formation of sulfate. A 13-step mechanism is proposed with rate-determining step ClO2- + SC(NH2)2 + H+ --> HOCl + HOSC(NH)NH2. Computer simulation using this mechanism gives good agreement with experiment.

引用

页码：5852 / 5856

页数：5

共 30 条

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