Corrosion inhibition of low carbon steel by leaves extracts of Coleus aromaticus Benth in sulphuric acid

Abstract

Corrosion inhibition by leaves extracts of Coleus aromaticus Benth (CAB) on mild steel (MS) in sulphuric acid medium was studied by using weight loss, AC impedance and potentiodynamic polarisation methods. The experiments were conducted to optimize the concentration of the inhibitors and time of exposure at room temperature and at high temperatures. To understand the nature of the adsorption process, thermodynamic and kinetic factors were assessed using temperature studies. Experimental results were incorporated into various adsorption isotherms. Durability of the inhibitor was assessed by using weight loss method. The findings of Tafel polarization and impedance experiments have been compared with the weight loss measurements. A possible mechanism of inhibition process was also suggested.