Recent advances in the use of benzimidazoles as corrosion inhibitors

Abstract

BackgroundBenzimidazole, a key heterocycle in therapeutic chemistry, and its derivatives, are recently mentioned in the literature as corrosion inhibitors for steels (CS, MS), pure metals (Fe, Al, Cu, Zn) and alloys. Benzimidazoles are good corrosion inhibitors for extremely aggressive, corrosive acidic media such as 1 M HCl, 1 M HNO3, 1.5 M H2SO4, basic media, 0.1 M NaOH or salt solutions. Benzimidazole derivatives act as mixed type inhibitors, exhibiting stronger inhibitive effect on the cathodic reaction than on the anodic one.ConclusionThese review highlights recent research in the field of benzimidazole compounds that their role as corrosion inhibitors, the structure of the compounds, electrochemical studies, the experimental conditions, the proposed mechanisms as well as the quantum theoretical studies that predict the structure of the compounds with inhibition properties.

Evaluation of 1‐Hexadecylbenzimidazole as a Corrosion Inhibitor on Low Carbon Steel 15 % HCl Solution Interface

“…A glance through the previous literature involving corrosion inhibition in 15 % HCl, as discussed in the introduction, reveals that the current HDBI inhibitor at a concentration of 50 mg L À 1 has demonstrated excellent corrosion inhibition efficiencies of 97 %. Note that most of the previous works [18][19][20][21][22][23][24][25][26][27][28] used much higher concentrations of inhibitors with lower inhibition efficiencies. The adsorption nature of HDBI on LCS was predicted to be mainly a chemisorption process as displayed by the estimated ΔG ads values above À 40 kJ mol À 1 for all investigated techniques and the E a value above the threshold of 80 kJ mol À 1 .…”

“…It can be attributed to the delocalized π-electron of the imidazole system and responsible for its effectiveness in adsorbing strongly on the surface of LCS. [27] The combined effect of the superior electronegativity (χ) [65] and lower chemical hardness (η) base on hard/soft-acid/base (HSAB) principle [66,67] enumerated in Table 7 is responsible for good performance of HDBI as a corrosion inhibitor of LCS in 15 % HCl solution. Besides, HDBI can also act as a strong electrophile possibly due to the higher value of electrophilicity (ω) in its protonated form and thereby undergo back-donation reaction by accepting electrons from the d-orbital of LCS.…”

“…[26] A recent article reviews the recent advances in benzimidazoles as mild steel corrosion inhibitors in 1 M HCl. [27] A 2-Mercaptobenzimidazole derivative at a concentration of 950 ppm has been shown to impart 78 % inhibition of mild steel corrosion in 1 M HCl at 60°C. [28] Our objective is to investigate the performance of 1-Hexadecylbenzimidazole (HDBI) as corrosion inhibition of LCS in 15 % HCl solution for acidization application.…”

Azole-Based Compounds as Corrosion Inhibitors for Metallic Materials

“…It was discovered for the first time by Hoebrecker as a part of vitamin B 12 [65]. In the last decades, benzimidazole, as well as its derivatives, has been reported as effective anticorrosion agents for many metallic materials such as mild and carbon steels [66,67]. The property of benzimidazole-based inhibitor to retard corrosion rate was attributed to the formation of an adsorbed protective film on the metal surface, which can consist of metal-benzimidazole complex or adsorbed benzimidazole molecules [68,69].…”

Microhardness and Fluoride Release of Glass Ionomer Cement Modified with a Novel Al+3 Complex to Enhance Its Antimicrobial Activity

“…Investigations revealed that it has antibacterial, antifungal, anthelmintic, and antipoliovirus activities [ 17 – 19 ]. It is made up of the reaction of 1,2-dihydroxyphenol and salicylic acid [ 20 ]. The chemical structure of 2-(2-hydroxyphenyl)-1H-benzimidazole is shown in Figure 1 .…”