Potato peel extract as an ecologically conscious inhibitor for corrosion of A283 carbon steel in hydrochloric acid: experimental and theoretical perspectives

Potato peel extract was validated as a safe and eco-friendly corrosion inhibitor for the carbon steel A283 grade C (CS A283) in 2.0 M HCl solution employing both chemical and electrochemical methods. The active constituents were successfully extracted using an alcoholic medium, and their chemical structures were identified by FT-IR, ¹H NMR, ¹³C NMR, and mass spectrometry analyses. The findings demonstrated that the corrosion rate drastically dropped in the presence of the potato peel extract, and the inhibition efficiency increased with an increase in concentration but decreased with an increase in temperature. Polarization data suggested that the potato peel extract functioned as a mixed-type inhibitor. The inhibition mechanism is attributed to the spontaneous and parallel adsorption of the extract’s main constituents onto the surface of CS A283 leading to the formation of an effective protective film against the corrosive acidic medium. The adsorption process is subjected to Langmuir isotherm. Furthermore, activation and adsorption thermodynamic parameters were evaluated and discussed. Several thermodynamic activation functions were determined and analyzed to better understand the corrosion and inhibition behavior. Scanning electron microscopy (SEM) was employed to analyze the surface morphological characteristics, affording a thorough understanding of the state of the surface and the degree of corrosion protection. The theoretical results indicated that the active constituents of potato peel extract can absorb onto the CS A283 surface. In addition, the study anticipates that petunidin and chlorogenic acid exhibit greater inhibition efficacy compared to the other components.