Original scientific paper
https://doi.org/10.5599/jese.242
Inhibition of carbon steel corrosion by 11-aminoundecanoic acid
Saad Ghareba
; Department of Chemical and Petroleum Engineering, Al-Mergib University, Alkhums Libya
Simon Kwan
; Department of Chemical Engineering, McGill University, Montreal, Quebec, Canada
Sasha Omanovic
; Department of Chemical Engineering, McGill University, Montreal, Quebec, Canada
Abstract
The current study reports results on the investigation of the possibility of using 11-aminoundecanoic acid (AA) as an inhibitor of general corrosion of carbon steel (CS) in HCl under a range of experimental conditions: inhibitor concentration, exposure time, electrolyte temperature and pH and CS surface roughness. It was found that AA acts as a mixed-type inhibitor, yielding maximum inhibition efficiency of 97 %. The adsorption of AA onto the CS surface was described by the Langmuir adsorption isotherm. The corresponding apparent Gibbs free energy of AA adsorption on CS at 295 K was calculated to be −30.2 kJ mol–1. The adsorption process was found to be driven by a positive change in entropy of the system. PM-IRRAS measurements revealed that the adsorbed AA layer is amorphous, which can be attributed to the repulsion between the neighboring positively charged amine groups and a high heterogeneity of the CS surface. It was also found that the AA provides very good corrosion protection of CS of various surface roughness, and over a prolonged time.
Keywords
Corrosion inhibition; Self-assembled monolayers; Adsorption; Acidic medium
Hrčak ID:
149439
URI
Publication date:
26.9.2015.
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