Effect of Organo-Nitrogen Compounds on Inhibition Efficiency of Mild Steel Corrosion in Acidic Media

Abstract

Some dodecylamine derivatives have been synthesized and were further elaborated by quaternization with an allyl group. The presence of diallyl moiety made some of these derivatives effective in inhibiting mild steel corrosion in acidic media. The study of mild steel corrosion was carried out using gravimetric and potentiodynamic polarization methods. At 60 °C, the inhibitors exhibited excellent inhibition efficiencies (% IE) of about 99 % (at 200 ppm) in 1 M HCl and about 11-97 % (at 400 ppm) in 0.5 M H2SO4. The inhibitors containing the diallyl moiety demonstrated the higher inhibition efficiencies in H2SO4. Some of the quaternary salts were effective in preventing corrosion in 3.5 % NaCl (% IE about 63-85 % at 200 ppm). The coordinate type of bond involving interactions of π-electrons with the iron d-orbitals allows the inhibitors to impede anodic oxidation of iron. The mechanisms emphasizing the role of the synthesized organonitrogen moieties in corrosion suppression process.