Corrosion Inhibition Of Mild Steel By Chemically Modified Lignin

In this research, the comparative structural characteristics of oil palm fronds (OPF) autohydrolyzed ethanol organosolv lignin (AH EOL) and modified autohydrolyzed ethanol organosolv lignin via incorporation of organic scavenger: p-hydroxyacetophenone (AHP EOL) was reported. Additionally, the antioxidant properties of the modified lignin shows better reducing power activity compared to the unmodified lignin. The inhibitive effect on the corrosion of mild steel in a 0.5 M HCl solution with and without addition of both types of lignin were studied using corrosion measurement techniques. It was revealed that the corrosion rate of the mild steel was reduced in the presence of lignin inhibitors with the highest inhibition efficiency, IE attained at at 500 ppm concentration for both lignin samples (IEAHP EOL: 82.83 % IEAH EOL: 71.90 %). The adsorption and thermodynamic data revealed that the inhibitors were physically adsorbed (physisorption) on the surface of the mild steel. SEM analysis showed that the surface morphology of the mild steel in the presence of modified lignin was improved.