Corrosion Inhibition on Carbon Steel in Hydrochloride Acid Using Some Bolaamphiphile Surfactants

Abstract

Novel Bolaamphiphile surfactants: 1,n-bis(4-amino-3-methyl-1,2,4-triazole-thioyl)alkane (DTCn, n=10,12) have been synthesized and characterized in the author's laboratory. The corrosion inhibition effect of carbon steel in molar hydrochloric acid was investigated using electrochemical methods, scanning electron microscope with energy dispersive x-ray analysis and theoretical tools such as density function theory calculation. This investigation shows that all compounds studied are good corrosion inhibitors for carbon steel in molar HCl. The inhibition efficiency increased with increasing inhibitor concentration, and reached 91.57% and 96.63% respectively for DTC10 and DTC12. The obtained results lead to the selecting the DTC12 as the best inhibitor. The surface analysis using SEM coupled with EDX confirms an excellent protective effect due to the establishment of the covering inhibitor film on the carbon steel surface. The density functional theory calculations were reasonably achieved to get a more understanding of the adsorption mechanism for corrosion inhibitors studied on the metal surface.