Kinetic and Mechanistic Study of the Reduction of Chromium(VI) by Lactic Acid

[摘要] The kinetics and mechanism of the reduction of chromium(VI) by lactic acid (Lac) in aqueous acidic medium wasstudied with spectrophotometry in a temperature range of 298.15 K~313.15 K. Under the conditions of the pseudo-first order([Lac]0≫[Cr(VI)]0), the observed rate constant(kobs)increased with the increase in [Lac] and[H+]. There is no salt effect. Based on the experimental results, a probable reaction mechanism of oxidation was proposed. The rate equation derived from the mechanism could explain all the experimental phenomena. Activation parameters along with rate constant of the rate-determining step have been evaluated.

[学科分类] 无机化学