Argan hulls extract as an efficient green corrosion inhibitor for copper in phosphoric acidic

The inhibitive behaviour of Argan hulls extract (AHE) , as a type of green inhibitor, on the corrosive behaviour of copper within an aqueous solution of 2M H3PO4 containing 3.10-1M NaCl. Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and gravimetric method, was used for the measurements at 298K. A significant decrease in the corrosion rate of copper was observed in the presence of the Argan hulls extract. Inhibition efficiency increases with AHE concentration to attain 91% at 6 g/L. The potentiodynamic polarization data indicated that the inhibitor was of mixed type. Impedance measurements showed that the charge transfer resistance increased and double layer capacitance decreased with increase in the inhibitor’s concentration. Also, some thermodynamic data for the activation are calculated and discussed. Results obtained from potentiodynamic polarization, impedance measurements and gravimetric method are in good agreement.