A Dialkyldithiophosphate Derivative as Mild Steel Corrosion Inhibitor in Sulfuric Acid Solution

In the present work, N,N-Diethylammonium O,O'-di(4-chlorophenyl)dithiophosphate (Cl-EPP) acting as a mild steel corrosion inhibitor was synthesized. Potentiodynamic polarization measurements, weight loss measurements and scanning electron microscopy were used to evaluate the corrosion inhibition of Cl-EPP for mild steel in sulfuric acid. The results of electrochemical measurements indicate that the Cl-EPP is a mixed type inhibitor. Meanwhile, the inhibition efficiency increase with the increasing of concentration of inhibitor concentration, decrease with the increasing of temperature, sulfuric acid concentration and storage time. In addition, the adsorption of Cl-EPP on mild steel surface is chemical adsorption, and obeys Langmuir isotherm.