Valorisation of leather buffing dust as corrosion inhibitor for mild steel in H2SO4 acid

Abstract

This work discusses the valorisation and efficacy of the acid-extracted collagenous proteins from leather buffing dust (LBD) on the corrosion inhibition of mild steel (MS) in 0.5 M H₂SO₄ solution using electrochemical analysis. The extract shows ~95 % inhibition efficiency at 1 wt% of raw LBD loading. The inhibitor interaction follows Langmuir adsorption isotherm, indicating monolayer adsorption through physisorption, leading to complex formation on the MS surface. Post-corrosion characterizations reveal film-forming nature of the inhibitor and the involvement of organic compounds in the complex protective layer formation on the MS in the corrosive media. In addition, surface study through an optical profilometer helps to understand the nature of the corroded MS. In summary, the LBD-H₂SO₄ extract is extremely capable in mitigating the corrosion of MS in H₂SO₄ solution, and the inhibition phenomenon is governed by a complex passive layer formation on the MS subjected to the corrosive media.