The development of environmentally benign corrosion inhibitors is critical to reduce the ecological impact of acid cleaning processes in industrial systems. This work presents an integrated approach to the discovery and application of green corrosion inhibitors for admiralty brass (AB), combining molecular-level studies of natural products with the valorization of agro-industrial waste.

In a first stage, latex extracts from Croton lechleri (Dragon’s blood), a native Amazonian species, were investigated as corrosion inhibitors in 0.5 M HCl. Phytochemical characterization revealed the presence of phenolic compounds and alkaloids, whose heteroatoms and π-electron systems promote adsorption on the metal surface. Electrochemical analyses, including potentiodynamic polarization and electrochemical impedance spectroscopy, demonstrated inhibition efficiencies up to 57% at low concentrations (50 ppm). Surface characterization (SEM, EDS, XPS) confirmed the formation of protective organic films that mitigate dezincification processes.

Building on this mechanistic understanding, a second stage explored low-cost inhibitor sources derived from agro-industrial residues. Extracts from Musa acuminata (banana) peels and Lupinus mutabilis debittering wastewater were screened using electrochemical methods. While banana extracts exhibited moderate efficiencies (~44%), the alkaloid-rich lupine extract achieved inhibition efficiencies above 80%, highlighting the effectiveness of waste-derived systems.

Finally, a techno-economic pre-feasibility analysis supports the scalability of the lupine-based inhibitor. This work bridges fundamental insights and applied screening, advancing sustainable corrosion protection strategies and promoting circular economy approaches based on Latin American biomass resources.