Rizatriptan Benzoate as Corrosion Inhibitor for Mild Steel in Acidic Corrosive Medium: Experimental and Theoretical Analysis

Abstract

Inhibition action of rizatriptan benzoate on corrosion of mild steel in 1 M HCl was evaluated through weight loss, potentiodynamic polarization and electrochemical impedance spectroscopic techniques. Corrosion study was conducted at different concentrations of inhibitor and at different temperatures. Inhibition action of the inhibitor on mild steel corrosion was found to increase with increase in concentration and also with increase in temperature. Polarization studies showed that the rizatriptan benzoate is a mixed type of inhibitor. Results obtained from chemical and electrochemical studies are in good agreement with one another. Inhibition action of the inhibitor is explained by adsorption process, and it follows Langmuir adsorption isotherm. The thermodynamic parameters calculated are in good agreement to say the process of adsorption is spontaneous. Surface analysis of the metal samples was studied by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy and atomic force microscopic techniques (AFM). SEM and AFM analysis further confirms the strong adsorption of the inhibitor on the mild steel surface, thereby mitigating the corrosion rate in aggressive media.