Watermelon waste products as green corrosion inhibitors for mild steel in HCl solution

Three agro-waste products namely; watermelon rind extract (WMRE), watermelon seed extract (WMSE) and watermelon peel extract (WMPE) were investigated for their corrosion inhibition potentials for mild steel in HCl solution using electrochemical techniques at 25 °C. All the extracts inhibited acid-induced corrosion of mild steel in the order WMSE > WMRE > WMPE. Corrosion inhibition effect was found to be dependent on extracts’ concentrations. Inhibitive action of the extracts could be attributed to adsorption of the extracts’ components on mild steel surface by physisorption mechanism according to Langmuir adsorption isotherm model and functions as mixed-typed inhibitors as revealed by potentiodynamic polarization studies.