Thermodynamic and Adsorption Analysis of Corrosion Inhibition of Mild Steel in 0.5M HCl Medium <i>via</i> Ethanol Extracts of <i>Phyllanthus mellerianus</i>

The corrosion of mild steel is a problem in industrial processes based on its deterioration exposure to acids, alkalis, and salt solutions. This issue has prompted an increase research interest order mitigate the harmful effects metals their alloys. thermodynamic adsorption analysis 0.5M hydrochloric acid solutions via ethanol leaf extract Phyllanthus mellerianus was investigated using weight loss hydrogen evolution techniques. powdered sample extracted with concentrated rotary evaporator. phytochemical reveals presence tannins, flavonoids, phenols, terpenoids at reasonable percentages. inhibition efficiency, enthalpy, enthropy, activation energy, Gibbs free isotherms were extrapolated some models. efficiency increased concentration extract. values change energy obtained 303K, 313K, 323K negative, indicating that Phyllanthus strongly adsorbed surfaces stable high temperatures. enthalpy ranges from 43.08kJ/mol 80.64kJ/mol. An inhibitor confirmed physical (physisorption) mechanism for surfaces. R2 linear regression are fitted Langmuir freundlich isotherms. inhibitory effectiveness extracts been attributed hetero atoms N, O, S present composition.