Inhibition Effects of Phenols on Corrosion of Mild Steel in Three Mineral Acids

Abstract

Inhibition by phenols on the corrosion of mild steel in nitric acid, sulfuric acid and hydrochloric acid media has been studied. A trend observed among the phenols in corrosion inhibition efficiency is p-cresol > m-cresol > phenol > 2-naphthol > 1-naphthol > 2-nitrophenol. Amongst naphthols, 2-naphthol was stronger inhibitor than 1-naphthol which appears to be relative to their structures. In general 2-naphthol and p-cresol are found to be stronger inhibitor over the range of concentrations of acids used. While phenol m-cresol and 1-naphthol shown greater inhibition efficiency when they are applied at higher concentrations. 2-Nitrophenol shows oxidizing nature in all the acids over the range of concentrations used.