Investigation on the Corrosion Inhibition Ability of Selected Plant Extracts on Mild Steel in Acid Media an Eco Friendly Approach for Preliminary Testing in Electroplating Industries

Abstract

The present work intends to assess the inhibitive properties of leaf extracts of Ailanthus excelsa newlineRoxb (AEL) ,Bauhinia racemosa Lam (BRL) and Hardwickia binata Roxb( HBL) as eco-friendly newlinecorrosion inhibitors for mild steel in 1M HCl and 0.5 M H2SO4 using weight loss potentiodynamic newlinepolarization and electrochemical impedance methods. Surface analytical techniques like SEM, EDX newlineand 3D laser profilometer were used to study the surface morphology. FTIR technique was used to newlineprove the probable mode of corrosion inhibition mechanism. Weight loss measurements were newlineperformed by immersing the mild steel coupons in triplicates in acid solution containing 100 mL newlinewithout and with various concentrations of plant extract at different period of immersion and newlinetemperature. The results obtained revealed that the inhibition efficiency increases with increasing newlineconcentration and time of immersion of AEL,BRL and HBL extracts respectively in 1M HCl and 0. 5 newlineM H2SO4 solution indicating that the adsorbed phytoconstituents of the extract are stable on mild steel newlinesurface at elevated temperatures and higher period of immersion .The investigated plant extracts afford newlinea maximum inhibition efficiency of 80-95% in both acid media .The data obtained from weight loss newlinemeasurements at different temperatures were fit into various adsorption isotherms .The activation newlineparameters of the investigated plant extracts for the corrosion inhibition process reveal kinetic and newlinemechanistic effect. Shelf life study was carried out using weight loss measurements in order to newlineevaluate the storage condition of the plant extract. Analysis of the results revealed that the plant newlineextracts were stable upto six months period of storage in the room temperature condition and affords newlinemaximum inhibition efficiency of 90%. Potentiodynamic polarization results reveal the mixed nature newline.Surface analytical techniques confirm the formation of protective film on the mild steel surface. newlinePreliminary field testing in electroplating industries revealed positive results.