Relationship between structure and inhibition behaviour of quinolinium salts for mild steel corrosion: Experimental and theoretical approach. (June 2015)

• Record Type: Journal Article
• Authors: Mourya, Punita; Singh, Praveen; Tewari, A.K.; Rastogi, R.B.; Singh, M.M.
• Is Part Of: Corrosion science. Volume 95(2015)
• Page Start: 71
• Page End: 87
• Publication Date: 2015-06
• Subjects: A. Mild steel -- B. Polarization -- B. EIS -- B. XPS -- B. AFM -- C. Acid corrosion; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2015.02.034
• Languages: English
• ISSNs: 0010-938X

Abstract

Graphical abstract: Highlights: Quinolinium salts are good corrosion inhibitor for mild steel in 0.5 M H2 SO4 . Inhibition efficiency successively increases with concentration and decreases with temperature. All the salts display inhibition efficiencies in the order of QUPRBR > QUETBR > QUPRI > QUMEI. XPS analysis has provided composition of adsorbed protective film on mild steel surface. Abstract: Corrosion inhibition behaviour of quinolinium salts on mild steel (MS) corrosion in 0.5 M H2 SO4 was investigated at various concentrations and temperatures by gravimetric and electrochemical techniques. The polarization curves indicated that these salts function as mixed inhibitors. Relevant kinetic and thermodynamic parameters like C R, E a, Δ H a 0, Δ S a 0, K ads and Δ G ads 0 were determined and discussed. The adsorption of salts on MS leading to inhibition was found to follow the Langmuir adsorption isotherm. The existence of a protective film on MS was confirmed by SEM and AFM techniques. XPS and quantum chemical calculations were carried out to establish the mechanism of corrosion inhibition.