Corrosion Inhibition of Copper Metal by Ethanolic Extract of Tinospora Cordifolia Plant in Sulfuric and Hydrochloric Acids of varying Strength (0.5 N to 3N) using Additives

Abstract

Abstract: Using typical weight loss and thermometric techniques, the inhibitory impact of Tinospora cordifolia stem and leaf extract on copper corrosion in H2SO4 and HCl solutions of varying strength( 0.5N,1N,2N,3N) was investigated. The outcomes demonstrated that extracts worked as outstanding and effective inhibitors in acidic conditions, both in the absence and addition of additives. In an acidic environment, Tinospora cordifolia stem extract outperformed leaves extract in terms of inhibitory efficiency.The maximal inhibitory efficiency for stem extract at maximum inhibitor concentrations of 0.8% was 96.54% and 99.19% in 0.5 N H2SO4 and 95.26% & 97.78% in 0.5 N HCl, respectively, in the absence and presence of additives (KI & K2SO4). Similar to this, the effectiveness of the leaf extract's inhibition was 95.37% and 97.84% in 0.5 N H2SO4 and 94.15% and 96.92% in 0.5 N HCl, at a maximum inhibitor concentration of 0.8% in the absence and addition, respectively, of additives (KI & K2SO4). Based on the findings, stem extract suppresses H2SO4 and HCl more potently than leaf extract.Surface coverage (θ) grows as inhibitor concentration rises (from 0.2% to 0.8%).The values of log(θ/(1-θ) increase linearly as inhibitor concentration rises,it has been demonstrated that ,the inhibitor's adsorption on the copper surface in the acid solutions followed Langmuir's adsorption isotherm. The current investigation discovered that the inhibitors (stem and leaf) were more effective at inhibiting the metal copper in H2SO4 and HCl acid solutions when an additive (KI and K2SO4) was present than when the inhibitors (stem and leaf) were present alone. Synergistic effects are to blame for this. The combined action of the two chemicals is more potent on a metal surface than the combined actions of the two chemicals acting separately or concurrently.