Harnessing the potential of Aegle marmelos pulp extract for sustainable corrosion inhibition of brass in 1M H2SO4: insights from characterization and optimization

Aegle marmelos (AM), commonly known as bael fruit, is a medicinal plant that has been used for centuries in traditional Indian medicine. In this work, the predictive capabilities of response surface methodology (RSM) and artificial neural networks (ANN) using MATLAB in modeling brass corrosion inhibition by AM pulp extract in acidic environment (1M H2SO4) were comparatively analyzed. The RSM studies measured the corrosion rate of brass in a 1M H2SO4 solution under different conditions, i.e., time, temperature, and the concentration of AM extract. The maximum inhibition efficiency was achieved at a time period of 24.72 h, 600 ppm of AM pulp extract concentration, and a temperature of 25.8°C. The UV studies showed that AM pulp extract adsorbed on the surface of brass, forming a protective layer that prevented the metal from corroding. The SEM images showed that the surface of brass in the presence of AM pulp extract was smoother than that of brass in the absence of AM pulp extract. The AFM images showed that the roughness of brass in the presence of AM pulp extract was lower than that of brass in the absence of AM pulp extract. The FTIR spectra showed that the absorption bands of the metal oxide on the surface of brass were weakened in the presence of AM pulp extract, indicating that the formation of metal oxide was inhibited. The results of this study suggest that AM pulp extract is an effective and eco-friendly corrosion inhibitor for brass in acidic environment. The study also provides insights into the mechanism of corrosion inhibition by AM pulp extract.