A kinetic and mechanistic study of oxidation of arsenic(III) by hexacyanoferrate(III) in aqueous ethanoic acid

Abstract

The kinetics of oxidation of As III by Fe(CN) 6 3) has been studied spectrophotometrically in 60% AcOH-H 2 O containing 4.0 mol dm )3 HCl. The oxidation is made possible by the difference in redox potentials. The reaction is first order each in [Fe(CN) 63) ] and [As III ]. Amongst the initially added products, Fe(CN) 6 4) retards the reaction and As V does not. Increasing the acid concentration at constant chloride concentration accelerates the reaction. At constant acidity increasing chloride concentration increases the reaction rate, which reaches a maximum and then decreases. H 2 Fe(CN) 6 ) , is the active species of Fe(CN) 6 3) , while AsCl 5 2) in an ascending portion and AsCl 2 + in a descending portion are considered to be the active species of As III . A suitable reaction mechanism is proposed and the reaction constants of the different steps involved have been evaluated.

A kinetic and mechanistic study of the oxidation of tyrosine by chromium(VI) in aqueous perchloric acid medium

“…We are particularly interested to see the mechanism of the oxidation of tyrosine by chromium(VI) in acidic media. This mechanism is of interest because of its non-complimentary nature and the possibility of a variety of mechanisms involving reactive intermediates such as chromium(V), chromium(IV), etc., all of which have been encountered in chemical reactions [3]. Hence, we have investigated the kinetics of oxidation of tyrosine by chromium(VI) in perchloric acid medium in order to identify the chromium(VI) intermediates and to arrive at a suitable mechanism.…”

Comparative Studies on Tributylammonium Chlorochromate Oxidation of Pentaammine Cobalt(III) Complexes of a-Hydroxy Acids Catalyzed by Benzalkonium Chloride

“…It is proved that Cr(VI) reagents is the best for the oxidation of most organic functional groups [1][2][3]. In recent years, more achievement were made using new Cr(VI) reagents such as tripropylammonium fluorochromate [4], pyridinium fluorochromate [5], tetrabutylammonium chlorochromate [6] and tetraethyl ammonium chlorochromate [7] etc., have been attempted to determine the kinetic and mechanistic route of various organic compounds [8][9][10][11][12][13][14][15][16].…”

Kinetics and mechanism of oxidation of aniline and substituted anilines by isoquinolinium bromochromate in aqueous acetic acid

“…A number of new chromium containing compounds like pyridinum bromochromate [1], quinolinium chlorochromate [2], 2,2'-bipyridinium chlorochromate [3], pyridinium fluorochromate [4], quinolinium fluorochromate [5], quinolinium bromochromate [6], quinolinium dichromate [7], pyridinium fluorochromate [8], imadazolium fluorochromate *Corresponding author. E-mail: svkhansole@yahoo.co.in [9] have been used to study the kinetics and mechanism of oxidation of various organic compounds.…”