EVALUATION OF CITRUS SINENSIS (ORANGE) PEEL EXTRACT AS A GREEN INHIBITOR FOR CARBON STEEL CORROSION IN HCl and H2SO4 SOLUTIONS

Abstract

This study investigated the corrosion inhibitory potential of Citrus sinensis (orange peel) extract on carbon steel in 1M hydrochloric and 1M sulphuric acid environments. Experimental results revealed that the extract exhibited notable inhibition efficiencies, reaching 76.92% in HCl and 72.97% in H₂SO₄ at 1.5 g/L concentration and 60°C. A clear inverse relationship between inhibitor concentration and corrosion rate was observed, highlighting the extract’s concentration-dependent behaviour. The higher performance in chloride-rich media suggests enhanced adsorption due to favourable molecular interactions. These findings underscore the thermal stability and versatility of Citrus sinensis extract across varied acidic conditions, reinforcing its suitability for sustainable corrosion management. As a green inhibitor derived from agro-waste, it offers eco-friendly advantages, cost efficiency, and the potential for industrial integration. Overall, the extract presented a compelling case for scalable application in corrosion control systems where environmental safety and chemical robustness are priorities.