Experimental investigation of sustainable Corrosion Inhibitor Albumin on low-carbon steel in 1N HCl and 1N H2SO4

Abstract

Sustainable corrosion inhibitors are being developed as many of them are ecologically friendly, biodegradable, and devoid of heavy metals and other potentially dangerous compounds. Albumin, a member of the globular protein family obtained from egg white, has found its application in a variety of various applications due to its intrinsic pharmacological qualities (anti-bacterial, immunomodulating, and anti-cancer angiotensin-converting enzyme inhibition). Herein, Albumin extract containing atoms with lone pairs of electrons such as Nitrogen (N), Oxygen (O) and having an aromatic ring (unsaturation) has been investigated as an eco-friendly inhibitor for low-carbon steel. The present work studied the inhibition action of Albumin extract for low-carbon steel in 1N acidic chloride and sulfate media using gravimetric, and electrochemical methods, viz potentiodynamic polarization (PDP) and AC impedance studies (EIS). The results obtained from PDP and EIS analysis revealed that the inhibitor exhibited anodic inhibition in 1N HCl (92.72%) and mixed-type but predominantly cathodic inhibition in 1N H2SO4 (79.23%). The studied green corrosion inhibitor followed Langmuir monolayer adsorption and the formation of a protective film on a low-carbon steel surface was confirmed with AFM and FT-IR results. Thus, Albumin extract exhibited excellent corrosion resistance on low-carbon steel.

Keywords

• Albumin extract
• Corrosion inhibition
• Low-carbon steel
• Langmuir adsorption isotherm
• Impedance spectroscopy