Kinetics and Mechanism of Oxidation of D-Penicillamine by Potassium Hexacyanoferrate(III) Ions in Aqueous Solution in the Presence of Sodium Dodecyl Sulphate and Cetyltrimethylammonium Bromide

A Mechanistic Approach to the Influence of Surfactants on the Oxidation of Ethyl Mercaptan and its Dimer Ethyl Mercaptan Disulfide by Hexacyanoferrate(III) Ions in Aqueous Medium

In this paper we report on the rate of oxidation of ethyl mercaptan and its dimer ethyl mercaptan disulfide by alkaline hexacyanoferrate(III) along with its mechanistic pathway, spectrophotometrically. The influence of different experimental parameters, such as change in concentration of EtSH, HCF, OH− and reaction temperature was studdie. It was observed that the order of reaction decreases in [EtSH] or [OH−] from first order to higher concentration, but it certainly did not tend towards zero order. The effect of surfactants on the rate of reaction was observed at the critical micelle concentration (CMC) of the surfactant and reported to be below the CMC. The investigators, thus, concluded that the added products have an insignificant effect on the reaction rate. Further, the activation parameters were evaluated which lend support to the proposed mechanism. The thermodynamic quantities were also determined and the binding parameters have also been evaluated using the Menger and Portnoy model.