Unveiling the anti-corrosion Potential of seaweed macroalga Codium tomentosum: A multifaceted investigation into its mechanisms of copper protection

Abstract

The seaweed macroalga Codium tomentosum (GAE) was extracted by the maceration method, and it was used as an eco-friendly, nontoxic inhibitor of copper in 1 M H2SO4 corrosion media. To evaluate the composition and protective capacity of the GAE, several methods were employed, gravimetric measurements, electrochemical testing include polarization curves and electrochemical impedance spectroscopy, Fourier infrared spectroscopy, UV–visible spectroscopy, and scanning electron microscopy. The findings indicate the green algae extract successfully prevents copper corrosion when immersed in a corrosive medium. The inhibition efficiency demonstrates an increase with rising inhibitor concentration, reaching its peak at 82 % at concentration of 1 g/L. Operating solely through adsorption and inhibiting active sites on the copper surface, the inhibitor has a mixed inhibition characteristic. Temperature sensitivity is observed, resulting in a decrease in efficiency. The hypothesis of physisorption nature and adherence to the Langmuir isotherm type is supported by the alignment of thermodynamic and kinetic research. In addition, the inhibition mechanism of GAE was studied by quantum chemical calculations and molecular Monte Carlo simulation. This work provides a useful insight into the anti–corrosion of copper during industrial pickling or descaling processes.