Inhibition effect of newly synthesized heterocyclic organic molecules on corrosion of steel in alkaline medium containing chloride

Two new organic compounds were tested experimentally as inhibitors for mild steel in NaOH in presence of NaCl by electrochemical and hydrogen evolution techniques. Results demonstrated that the two inhibitors show an adsorption on steel surface according to Langmuir adsorption isotherm. The inhibition efficiency increases with increasing inhibitor concentrations to attain a maximum value at 1.0 mM for compound I and at 6.0 mM for compound II, respectively. The results were confirmed by surface examination via scanning electron microscope.