Alkaline Corrosion Control Using Sustainable Natural Inhibitors

Abstract

Using natural corrosion inhibitors from calcium carbonate has gained attention in corrosion prevention approaches as it offers comparable and significant benefits compared to other corrosion inhibitors. Consequently, eggshells with a high amount of calcium carbonate were proposed as a corrosion inhibitor to evaluate the effect on the corrosion behavior of mild steel. In this study, eggshell waste was extracted in an ethanol solution using a Soxhlet extractor and concentrated using a rotary evaporator to produce the proposed natural corrosion inhibitor. The characteristics of the inhibitor were then examined and verified through FTIR and XRD analysis. The corrosion performance was then evaluated through the weight loss method in 30% Sodium Hydroxide. The corrosion rate and inhibiting efficiency were also performed to analyse the effect of eggshell concentration on the mild steel. Additionally, increasing the eggshell concentration decreases the corrosion rate and increases the inhibitor efficiency. This is due to CaCO3 in eggshells, a barrier to metal surfaces. Results indicate that selecting eggshell as a natural corrosion inhibitor successfully and confirmable protected the surface. Thus, this study is a viable utilization of sustainable use from eggshell waste in reducing the corrosion occurrence of mild steel in an alkaline environment.