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In this study, the kinetics and mechanism of the iridium(Ⅲ)-catalyzed oxidation of ethanol amine(EAN) by cerium(Ⅳ) in a sulfuric acid medium was investigated using titrimetric technique of redox in a temperature range of 298—313 K. It was found that the reaction is of first order with respect to Ce(Ⅳ) and Ir(Ⅲ), and a positive fractional order with respect to EAN. It was also found that the pseudo-first-order([EAN][Ce(Ⅳ)]) rate constant kobs decreases with the increase of [H+] and [HSO-4]. Under the protection of nitrogen gas, the reaction system can initiate the polymerization of acrylonitrile, indicating the generation of free radicals. On the basis of the experimental results, a suitable mechanism was proposed. From the dependence of kobs on the concentration of hydrogen sulfate, Ce(SO4)2 was found to be the kinetically active species. The rate constants of the rate-determining step together with the activation parameters were evaluated.
In this study, the kinetics and mechanism of the iridium (III) -catalyzed oxidation of ethanol amine (EAN) by cerium (IV) in a sulfuric acid medium was investigated using titrimetric technique of redox in a temperature range of 298-313 K. It was found that the reaction is first order with respect to Ce (Ⅳ) and Ir (Ⅲ), and a positive fractional order with respect to EAN. It was also found that the pseudo-first-order ([EAN] [ Ce (IV)]) rate constant kobs decreases with the increase of [H +] and [HSO-4]. Under the protection of nitrogen gas, the reaction system can of acrylonitrile, indicating the generation of free radicals. basis of the experimental results, a suitable mechanism was proposed. From the dependence of kobs on the concentration of hydrogen sulfate, Ce (SO4) 2 was found to be the kinetically active species. The rate constants of the rate-determining step together with the activation parameters were evaluated.