Green Corrosion Inhibition of Brass in Acidic Environments Using Sustainable Plant Extracts: Efficiency, Stability, and Mechanisms

This study investigates the corrosion inhibition performance of three plant-derived extracts—Marigold flower (Tagetes erecta), Ashoka seed (Saraca asoca), and Rosemary leaf (Rosmarinus officinalis)—on C26000 brass in 1M HCl and 0.5M H₂SO₄. Electrochemical and surface characterization techniques revealed inhibition efficiencies of 94.2%, 93.09%, and 98.33%, respectively, with Rosemary extract (ROLE) exhibiting superior performance. All extracts retained >89% efficiency after 30 days, demonstrating exceptional long-term stability. FTIR and SEM/EDS confirmed chemisorption via polar functional groups (O-H, C=O). Cost-benefit analysis showed that green inhibitors reduced costs by up to 60% compared to benzotriazole. This work validates the industrial potential of plant-based inhibitors as sustainable alternatives for corrosion protection, aligning with UN Sustainable Development Goals 9 and 12 [1].