Inhibition Performance of a New Series of Mono-/Diamine-Based Corrosion Inhibitors for HCl Solutions

Abstract

Summary New mono- and diamine compounds were synthesized from dodecylamine and 1,12-dodacanediamine and evaluated as acid corrosion inhibitors for low-carbon steel. The inhibition behavior of these compounds was examined using gravimetric and electrochemical methods (linear polarization and Tafel plot). Weight-loss tests were conducted in 1M HCl at 60°C for six hours. To simulate acid stimulation treatments, other weight-loss tests were conducted using typical acid stimulation concentrations of 4.1 and 7.7M HCl at 60°C for 2 hours. The effects of corrosion inhibitor type, concentration, and acid concentration were investigated. Aromatic and multiple bonds substituents introduced to mono-and diamine compounds were found to enhance inhibition performance compared to the starting materials (dodecylamine and 1,12-dodacanediamine). This is attributed to the π-electrons present in aromatic and to polymerization of substituents with multiple bonds. Both dodecylamine derivatives with a triple bond or an aromatic substituent exhibited excellent protection in 4.1M HCl. However, the derivative with a triple bond showed the best protection (98%) at 7.7M HCl. This result is very promising and suggests that this corrosion inhibitor has a good potential to be used in acid stimulation treatments conducted in oil and gas wells.