Corrosion inhibitors performance for mild steel in CO₂ containing solutions

Abstract

The Electrochemical Impedance Spectroscopy (EIS), was used to evaluate and compare the behavior of three different corrosion inhibitors: quaternary amine (QA), oleic imidazoline (OI) and amino coco propionic acid (ACP), on the corrosion of mild steel in 3% NaCl solutions, saturated with CO 2 gas, under static conditions. Two pH values: 3.8 and 5.5 were considered. Under the conditions considered in this work, the results indicated film formation at the metal surface, probable due to the formation of iron carbonate. This condition modified the values of the resistance and double layer capacitance of the system. In general terms, the ACP inhibitor exhibited better performance, compared to the QA and OI. During the impedance measurements with OI and ACP, some deviations were observed at high frequencies, indicating probably that the inhibitors adsorption occurs in different way to the QA inhibitor and the amine adsorption is weaker than the other two inhibitors adsorption.

Corrosion inhibition mechanism of aromatic amino acids for steel in alkaline pore solution simulating carbonated concrete environment

“…The presence of films and their protective action has also been reported by various other authors with inhibitors in concrete simulating pore solutions. [57] These observations are in compliance with the PDP curves where the performance of Phe improved with immersion time, suggesting that the inhibitor ions take some time to get stabilized in the pore solution and perform their inhibitory action, especially when the number of ions is more/increased. Furthermore, the size of the frequency arcs and obtained EIS parameters are comparable in the case of C0+Phe0.05 as compared to C0+Phe0.1 at 240 h.…”

Analysis of the use of environmentally friendly corrosion inhibitors for mild steel in a carbon dioxide saturated chloride solution via experimental design

“…In summary, quaternary amine seems to be the least influential in inhibiting corrosion, since an increase or decrease of C level leads to a lower change in inhibition efficiency. Zavala Olivares et al conclude that the adsorption of oleic imidazoline occurred in a different way to the adsorption of the quaternary amine, or that the adsorption of imidazoline component was stronger than the adsorption of the quaternary amine inhibitor of mild steel in 3% NaCl CO 2 ‐saturated solutions.…”

State-of-the-art overview of pipeline steel corrosion in impure dense CO2 for CCS transportation: mechanisms and models

“…The performance of various inhibitors in CO 2 -saturated aqueous phase has been studied for the oil and gas transportation purpose [3,[162][163][164][165][166][167][168][169][170][171], and most of the tests were under low CO 2 partial pressure conditions. Imidazoline-based inhibitors are extensively used in oil and gas industry to mitigate CO 2 corrosion.…”