Investigation of Corrosion Inhibition Activity of 3-butyl-2,4,5-triphenylimidazole and 3-butyl-2-(2-butoxyphenyl)-4,5-diphenylimidazole toward Carbon Steel in 1% NaCl Solution

Overcoming of corrosion problem on the surface of carbon steel is still being developed until present. The recent publications showed that the corrosion inhibitor with good hydrophobic properties and strong interaction with the carbon steel surface is needed. Therefore, 3-butyl-2,4,5-triphenylimidazole and 3-butyl-2-(2-butoxyphenyl)-4,5-diphenylimidazole were synthesized to be applied as corrosion inhibitors. The synthesis of 3-butyl-2,4,5-triphenylimidazole (1) and 3-butyl-2-(2-butoxyphenyl)-4,5-diphenylimidazole (2) were carried out by a Microwave Assisted Organic Synthesis (MAOS) method. The results of Electrochemical Impedance Spectroscopy (EIS) measurements show that the adsorption mechanism of 3-butyl-2,4,5-triphenylimidazole and 3-butyl-2-(2-butoxyphenyl)-4,5-diphenylimidazole onto carbon steel surface obeyed Langmuir adsorption isotherm with the value of Delta G(ads) are -34.49 kJ.mol(-1) and -40.19 kJ.mol(-1), respectively, which correspond to the spontaneous interaction between corrosion inhibitors and carbon steel surface by semi-chemisorptions and chemisorptions interaction.