Performance of Some Natural Carbohydrate as Corrosion Inhibitor: A Comprehensive Review

Abstract

This review describes the application of Carbohydrate biopolymers as green inhibitors for inhibition of metal corrosion. The protective capacity and precise mechanisms of these green inhibitors depend heavily on their molecular weight, chemical composition and unique electronic configurations. For instance, cellulose and chitosan possess free amine and hydroxyl groups. These groups contain heteroatoms (nitrogen and oxygen) with lone pairs of electrons. These lone pairs are shared with the vacant d-orbitals of the metal, forming coordinate bonds that create a protective molecular film over the metal surface. A detailed analysis is provided for various carbohydrate biopolymers including gums, alginates, starch, carboxymethyl cellulose, and hydroxyethyl cellulose—alongside an evaluation of how halide additives synergistically improve their anti-corrosion efficiency is discussed.