The controlling role of new imidazole-based ionic liquids on the corrosion rate of steel rebars in the cement pore solution

Abstract

The new group of ionic liquids based on imidazole molecule has been considered as promising anti-corrosion additives (admixed additives) to protect the steel rebars in the cement pore solution. In this paper, four new ionic liquids based on imidazole molecule are synthesized and characterized. Herein, the corrosion prevention properties of new ionic liquids are explored by chemical and electrochemical tests. The electrochemical tests proved that the new ionic liquids hinder both the cathodic and anodic processes and increase the corrosion resistance. The mass loss tests indicated that the performance capabilities of the synthesized ionic liquids are between 76% and 95%. Here, the new compounds reduce the corrosion of the steel rebars in the cement pore solution. This situation depends on the type of cation and the concentrations of ionic liquids. The responsibility of ionic liquids as anti-corrosion additives is centered on their adsorption ability. Langmuir isotherm is the best isotherm for the adsorption process. The obtained Gibbs free energies point to chemi-physisorption of ionic liquids.