Thermodynamic study of Green Corrosion Inhibitor on Mild Steel with Aqueous Extract of Ziziphus Jujuba Stem and Fruits in 1M HCl Solution

Abstract

The Corrosion inhibition of mild steel in 1 M HCl solution with aqueous extract of Ziziphus Jujuba stem and Ziziphus Jujuba fruits is studied by weight loss method at 303-333K temperatures. It is found that inhibition efficiency rise with increase in concentration of extract and decreased with rise in temperature. Maximum 78.05% inhibition efficiency was observed at 303 K and 8% (v/v) concentration of Ziziphus Jujuba stem. While maximum 68.60% inhibition efficiency was observed at 303 K and 8% (v/v) concentration of Ziziphus Jujuba fruits. Value observed for Activation energy, Gibbs free energy and variation in I.E. with temp Suggest physisorption. Adsorption of extract at mild steel surface follows Langmuir adsorption isotherm. Negative values of Gibbs energy reveals the spontaneity of inhibition process in extracts at studied temperatures.