International Journal of Scientific Research and Engineering Development

The corrosion behaviour of 62/38 brass in nitric acid and its inhibition by Mimosa pudica (Lajamani) seed extract were investigated using gravimetric, electrochemical, adsorption, and surface characterization techniques. Weight loss measurements showed that inhibition efficiency increased with inhibitor concentration (0.50–1.50 g L⁻¹) and decreased with increasing acid concentration (0.50–1.50 M) and temperature (303–323 K), indicating concentration-dependent and temperature-sensitive behaviour. Adsorption of the inhibitor followed the Langmuir adsorption isotherm, suggesting monolayer formation on the metal surface. The calculated values of standard free energy of adsorption (ΔG°ads) ranged from −18.95 to −24.32 kJ mol⁻¹, indicating spontaneous adsorption predominantly governed by physical interaction. The increase in activation energy in the presence of inhibitor further supported the formation of an energy barrier for the corrosion process. Potentiodynamic polarization studies revealed a decrease in corrosion current density with a slight shift in corrosion potential, indicating that Mimosa pudica extract acts as a mixed-type inhibitor affecting both anodic and cathodic reactions. Surface characterization using SEM, EDX, AFM, and FTIR confirmed the formation of an adsorbed protective layer on the brass surface, although the film was not fully compact. Overall, Mimosa pudica extract functions as a green corrosion inhibitor for brass in nitric acid through an adsorption-controlled mechanism, with moderate inhibition efficiency governed by predominantly physical adsorption.

Tanvi Mahla, M.B.Mahida,"Corrosion Inhibition of Brass in Nitric Acid Using Mimosa pudica Seed Extract: Gravimetric, Electrochemical, Adsorption and Surface Characterization Studies" International Journal of Scientific Research and Engineering Development, V9(3): Page(130-144) May-June 2026. ISSN: 2581-7175. www.ijsred.com. Published by Scientific and Academic Research Publishing.