The inhibition action of tyrosine on the corrosion of low chromium steel in 7 wt percent sulfamic acid

Abstract

Purpose

The purpose of this paper is to carry out laboratory studies of the inhibition effect of tyrosine (Tyr) on the corrosion of low chromium alloy steel (ASTM A213 grade T22) in 7 wt percent sulfamic acid solutions.

Design/methodology/approach

The corrosion inhibitive effect of Tyr was investigated using electrochemical impedance spectroscopy (EIS) and the new technique electrochemical frequency modulation (EFM).

Findings

It was found that the inhibition efficiency increased with increasing inhibitor concentration, while a decrease was detected with the rise of temperature and stirring speed. The corrosion inhibition is due to physical adsorption of Tyr on the steel surface. Adsorption of the inhibitor molecule, onto the steel surface follows the Temkin's adsorption isotherm.

Originality/value

The obtained results from both methods (EIS and EFM) at different experimental conditions were in high agreement and almost similar. This is an indication that the EFM technique can be used efficiently for monitoring the corrosion inhibition under the studied conditions.

Citation

Tawfik M. Abdel‐Fatah, H. (2012), "The inhibition action of tyrosine on the corrosion of low chromium steel in 7 wt percent sulfamic acid", Anti-Corrosion Methods and Materials, Vol. 59 No. 1, pp. 23-31. https://doi.org/10.1108/00035591211190517