Inhibition Performance of an Imidazolidinethion Derivative Inhibitor

A kind of imidazolidinethion inhibitor (CI-R inhibitor) was synthetised with diethylenetriamine, thiourea and lauric acid as raw materials. Weight loss method, potentiodynamic polarization measurement and scanning electron microscopy (SEM) were used to investigate the inhibition performance of the CI-R inhibitor for carbon steel in 500 μg/g HCl + 1% NH₄Cl solution at 85℃. The results showed that the inhibitor CI-R, acting as a mixed-type inhibitor, could inhibit the corrosion of carbon steel in test solution significantly. The inhibition efficiency was up to 90.9% at the concentration of 20 μg/g. Its adsorption on the metal surface obeys Langmuir adsorption isotherm. The inhibitor forms a product film on the metal surface by adsorption, resulting in high protection performance for carbon steel.