Abstract

Microbiologically induced corrosion (MIC) poses significant risks to buried oil pipelines, leading to structural damage, leakages, environmental contamination, and substantial economic losses. With increasing regulatory restrictions on chemical biocides, there is an urgent need for eco-friendly and sustainable corrosion control strategies. This study investigates Chromolaena odorata ethanol extracts (COEE) and Chromolaena odorata aqueous extracts (COAE) as nature-friendly, low-cost inhibitors for managing MIC in buried metals. Mild steel coupons preconditioned with each extract were buried in a biocorrosion-simulating soil system with COEE, COAE, and control (no extract) setups. Gravimetric analysis at 14 and 28 days assessed the impact of the extracts on corrosion. Results showed that, by Day 28, the percentage weight loss for COEE, COAE, and control were 0.86%, 0.79%, and 1.73%, respectively, with corresponding corrosion rates of 11.74, 10.71, and 23.43 mpy. The inhibition efficiencies for COEE and COAE reached 50% and 53%, indicating substantial corrosion reduction. Statistical analysis with Tukey HSD confirmed significant differences in weight loss between treated setups and the control, with no significant difference between COEE and COAE, indicating comparable efficacy. These findings validate C. odorata extracts as promising, eco-friendly alternatives for MIC management in buried pipelines, offering effective corrosion protection with minimal environmental impact.