Micellar Effects on Oxidation of Co(II)‐EDTA Complex With Quinolinium Dichromate‐A Kinetic and Mechanistic Study

ABSTRACT The oxidation of Co(II)‐EDTA with QDC in acidic medium is carried out in anionic, cationic, and non‐ionic micellar media. The stoichiometry of the reaction between Co(II)‐EDTA and QDC is 6:1. Ionic strength is maintained using sodium perchlorate, which does not influence the reaction rate. The reaction has shown first‐order kinetics with varying [QDC] & [Co(II)‐EDTA]. The reaction rate is inhibited with an increase in [H + ]. The reaction rate increases with increasing [SDS]; at [SDS] >> cmc, it decreases. The [Surfactant] rate profile shows a maximum, indicating that the reaction is bimolecular on the micellar surface. The reaction kinetics are accelerated fourfold in the presence of varying [Triton‐X‐100] and reach a limiting value, which indicates that the reaction is unimolecular on the micellar surface. Under the experimental conditions, CTAB has shown suspension. Berezin treatment is applied to the kinetic data, and the rate constant in the aqueous phase is determined from the binding constants of QDC and Co(II)‐EDTA with SDS and Triton‐X‐100 micelles.