Effect of micelles on hydrolysis of di-2,3-dichloroaniline phosphate

Abstract

The effect of anionic surfactant, di-octyl sodium sulphosuccinate (AOT) and nonionic surfactant, polyoxyethylene sorbitan monooleate (Tween-80) on the hydrolysis of di-2,3-dichloroaniline phosphate was studied spectrophotometrically at 303 K. The influence of inorganic salts on the reaction rate was studied. The added salts viz. KCl, KNO₃, and K₂SO₄ accelerated the rate of the reaction in the presence of anionic and nonionic micelles. The role of anionic and non-ionic micelle has been explained by the Menger-Portnoy, and Piszkiewicz models. The binding constant (K_s), rate constant (k_ψ) in the micellar phase, cooperativity index (n) and various thermodynamic activation parameters viz. ∆E_a, ∆S^≠, ∆H^≠, ∆G^≠ etc. have been evaluated. Possible reaction mechanism has been proposed on the basis of the observed kinetic data.