The Open Corrosion Journal

2010, 3 : 58-63
Published online 2010 July 16. DOI: 10.2174/1876503301003010058
Publisher ID: TOCORRJ-3-58

The Inhibited Effect of Cysteine Towards the Corrosion of Copper in Nitric Acid Solution

K. Barouni , M. Mihit , L. Bazzi , R. Salghi , S.S. Al-Deyab , B. Hammouti and A. Albourine
LCAE-URAC18, Faculté des Sciences, Université Mohammed premier, B.P 717, 60000 Oujda, Morocco

ABSTRACT

The detailed study of cysteine (Cys) as corrosion inhibitor for copper in nitric acid solution has been performed through weight loss, electrochemical polarization, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) measurements. The effect of inhibitor concentration, temperature and immersion time against inhibitor action was investigated. Results show that Cys may be used as an efficient inhibitor for copper in nitric acid at higher temperatures (98% at 50°C). Potentiodynamic polarization studies reveal that Cysteine acts as a mixed-type inhibitor without any change in the mechanism of hydrogen evolution. The adsorption of this compound on copper surface obeys Langmuir’s adsorption isotherm and has a chemisorptions mechanism.

Keywords:

Corrosion, inhibition, copper, amino-acids.