Journal de génie chimique avancé

Abstrait

Kinetics of Bimolecular Reaction on Activation Parameters for the Solvolysis of Diethyl Phthalate in Aqueous Alkaline Medium of Ethanol

Anil Kumar Singh

The kinetics parameters like rate constant, iso-composition activation energy, dielectric activation energy, enthalpy of activation, entropy of activation and Gibb’s free energy of activation for the alkali catalyzed hydrolysis of diethyl phthalate ester have been determined at different range of composition for mixture of water and organic solvent at different range of temperature. The effect of solvent on rate of reaction has been studied on term of salvation and desolvation concepts. The number of water molecule associated with activated complex has been found to be decreases with increase of temperature from 200°C to 400°C, this indicate the mechanistic path followed by the reaction change from unimolecular to bimolecular. The variation of ΔG*, ΔH*, ΔS* with solvent composition and the specific effect of water on the reaction rate kinetics are also discussed. Linear plots of ΔH* versus ΔS* were obtained and the isokinetic temperature (greater than 300°C) indicates that the reaction is entropy controlled. The results are discussed in terms of polarity of medium and the change in solvent structure.