Corrosion inhibition and thermodynamic activation parameters of Myrtus communis extract on mild steel in sulfamic acid medium

Abstract

The effect of an aqueous extract of Myrtuis communis on the corrosion behavior of mild steel (MS) in 5% NH2SO3H solution has been investigated by the following techniques: weight loss (WL), potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS), and electrochemical frequency modulation techniques (EFM). The inhibition efficiency (IE) increased with increase in inhibitor dose and increased with rise in temperature. The thermodynamic parameters of corrosion and adsorption processes were calculated and discussed. The adsorption of this extract was found to obey Langmuir adsorption isotherm. The PP tests indicated that the extract is mixed type. The results obtained from the three different techniques were in good agreement. The morphology of the surface was analyzed and discussed.