Pectin as a Potential Green Inhibitor for Corrosion Control of 6061Al–15%_(V) SiC_(P) Composite in Acid Medium: Electrochemical and Surface Studies

The studies on corrosion control of 6061Al–15%_(V) SiC_(P) composite (AlMMCs) in 0.025 M HCl have been carried out by employing electrochemical techniques like potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) using biopolymer pectin as inhibitor. Pectin showed increase in the inhibition efficiency, when the concentration of it was increased from 0.2 to 1.0 g L⁻¹. Inhibition efficiency also increased with increasing the temperature of corrosive medium from 303 to 323 K. The thermodynamic and kinetic calculations showed that pectin underwent chemisorption by following Langmuir adsorption isotherm. Surface morphology studies were carried using scanning electron microscopy (SEM), and it was supported by elemental analysis performed by using energy-dispersive x-ray (EDX) analysis technique. Suitable mechanism was proposed for the corrosion inhibition process. Maximum inhibition efficiency of 95% was observed for the addition of 1 g L⁻¹ of pectin. Pectin emerged as an excellent green corrosion inhibitor for the corrosion control of AlMMCs in acid medium, with environment benefits.