Performance evaluation of pectin as ecofriendly corrosion inhibitor for \X60\ pipeline steel in acid medium: Experimental and theoretical approaches
By Saviour A. Umoren and Ime B. Obot and A. Madhankumar and Zuhair M. Gasem
Published in Carbohydrate Polymers
2015
Abstract
The corrosion inhibition effect of pectin (a biopolymer) for \X60\ pipeline steel in \HCl\ medium was investigated using weight loss, electrochemical, water contact angle measurements, and scanning electron microscopy techniques. The results obtained show that pectin acts as a good corrosion inhibitor for \X60\ steel. Inhibition efficiency increased with increase in pectin concentration and temperature. Potentiodynamic polarization results reveal that pectin could be classified as a mixed-type corrosion inhibitor with predominant control of the cathodic reaction. The effective corrosion inhibition potential of pectin could be related to the adsorption of pectin molecules at the metal/solution interface which is found to accord with the Langmuir adsorption isotherm model and a protective film formation. Quantum chemical calculations provided insights into the active sites and reactivity parameters governing pectin activity as a good corrosion inhibitor for \X60\ steel.