Corrosion inhibition effect of mebendazole on 5Cr pipeline steel in 1 M HCl solution

Abstract

In this manuscript, the ability of (5-Benzoyl-1H-benzimidazol-2-yl) carbamicacidmethylester (mebendazole, MBD) as an inhibitor of corrosion on 5Cr pipeline steel in HCl medium was explored. Corresponding electrochemical tests, immersion tests and other experiments were designed, and at the same time, the ability of mebendazole to inhibit corrosion of 5Cr steel in HCl medium was screened and proved by means of molecular weight simulation calculation analysis process, and its possible anticorrosion mechanism was also revealed. Electrochemical test results show that mebendazole can successfully prevent 5Cr steel from dissolving in HCl medium, and the inhibition efficiency is particularly significant with the increase of mebendazole content. According to the electrochemical impedance test, the highest corrosion inhibition efficiency (η) can reach 94.4 %. The results of immersion weight loss experiment are highly consistent with the electrochemical test data and SEM electron microscope morphology. From the theoretical calculation results, it can be found that under neutral conditions and protonated mebendazole molecules have lower energy gaps and higher dipole moments in solvated and unsolvated environments, and can Parallel adsorption on the metal surface, which also corresponds to its efficient corrosion inhibition performance. In addition, through comparison, it is found that the protonated mebendazole molecule under solvation conditions has the highest binding energy, that is, it is the easiest to interact with 5Cr steel and presents the best anti-corrosion performance.