Evaluation of the Corrosion Inhibition Potential of Eco-Friendly Kaffir Lime Leaves in Mild Steel Pipelines

Abstract Corrosion is the negative outcome of the chemical interaction between metal or metal alloys and the surroundings. Engineers face myriad challenges in petroleum production and transportation systems because of corrosion. Hence, it is imperative to prevent/mitigate this undesirable process. Hence, the study explored the corrosion inhibition potential of kaffir lime leaf extract (KLLE) on mild steel pipelines. The corrosion inhibition potential of KLLE at different concentrations (0–10000 mg/L) in 1 M HCl was investigated at 298K for 24 hours. KLLE was characterized using Fourier Transform Infrared Spectroscopy (FTIR) and the mild steel surface morphology was examined using Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive Spectroscopy (EDS). The initial and final weights of six mild steel samples were measured. The weight loss was ascertained to determine the inhibition efficiency, corrosion rate, and surface coverage of KLLE on the mild steel samples. The corrosion inhibition efficiency of KLLE was compared to other inhibitors. EDX revealed the formation of abundant ferric compounds (corrosion promoters) on the mild steel surface in the absence of KLLE. However, KLLE incorporation precluded ferric compound formation by adsorbing to the mild steel surface. KLLE exhibited remarkable performance in inhibiting mild steel corrosion. KLLE yielded an inhibition efficiency and surface coverage of 93.79% and 0.94 respectively at a low concentration of 4000 mg/L. FESEM results also showed a relatively smoother steel surface and fewer pits in the presence of KLLE compared to its absence. KLLE inhibition efficiency surpassed that of other citrus family plant extracts and organic inhibitors. The study provides valuable insights into the exceptional performance of an environmentally friendly extract in mild steel corrosion inhibition. The application could corroborate efforts in minimizing or preventing corrosion in mild steel pipelines.