Inhibition effect of The Hylocereus Polyrhizus Skin Extract as Green Corrosion Inhibitor for API 5L-B Steel in Corrosive Solution

The effectiveness of Inhibitor Red dragon fruit (Hylocereus polyrhizus) skin extract (IRSE) in the corrosion inhibition of steel in the corrosive environment of 3.5 % NaCl and HCl pH-3 solutions was investigated by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) techniques. The corrosion rate of carbon steel and the inhibition efficiency of the IRSE were calculated. The weight loss results showed that skin extracts worked optimally and were able to inhibit the corrosion. The Tafel polarization curves showed that the extract at The inhibition efficiency increased as the concentration of the extract increases. Potentiodynamic polarization and electrochemical impedance spectroscopy are in a good agreement where the maximum inhibition is around 89,1%. The inhibitive action of the extract is discussed based on the adsorption of a stable complex on the steel surface. The results obtained showed that IRSE inhibited the corrosion process by a physical adsorption mechanism that followed the Langmuir adsorption isotherm mode