Inhibition of Mild Steel Corrosion in Hydrochloric Acid Solution by Leaves of Ziziphus jujuba

Abstract

Weight loss method was used to assess the inhibition of mild steel corrosion in 1M HCl solution with aqueous extract of Ziziphus jujuba leaves at 303 to 333K temperatures. It was found that Ziziphus jujuba leaves extract retarded the dissolution of mild steel in 1M HCl solution. The inhibition efficiency increases with a rise in the concentration of extract and decreases with increase in temperature. Maximum 88.54% inhibition efficiency was observed at 303 K and 8% (v/v) composition of the extract. Adsorption of extract at mild steel surface follows Langmuir adsorption isotherm. Values of Gibbs free energy, variation in inhibition energy with temperature and with activation energy values trend proposed the physisorption. Negative values of Gibbs energy propose the spontaneous process of inhibition process in the extract at studied temperatures.