The kinetic investigation of oxidation of thiourea by quinolinium dichromate (QDC) in perchloric acid medium at constant ionic strength was studied spectrophotometrically at 440 nm. A stoichiometric ratio of 3:1 with thiourea versus QDC was observed. The reaction was first order with respect to thiourea, monomeric QDC (QMC) and HClO4. Induced polymerization of acrylonitrile was observed. The mechanism involved the attack of protonated monomeric QDC (QMC) on the substrate in the rate determining step forming the products. Addition of Mn(II) has no effect on the reaction rate. The effect of anionic micelle (SDS) and neutral micelle (TX-100) on the system was studied using Berezinís kinetic model and observed a partial inhibitory effect on the rate of the reaction. The thermodynamic parameters like ΔEa ΔS and ΔG have been calculated and possible mechanism was proposed.
Monomeric quinolinium dichromate, QMC, Oxidation, Effect of anionic and neutral (TX-100) micelle