Lignin from termite frass: a sustainable source for anticorrosive applications

Abstract

The present study reports a sustainable source of lignin, from termite frass. Lignin was extracted using Klason’s method and subjected to polarization studies to check the inhibition efficiency and measured the electrochemical performance of the coated sample on the carbon steel using electrochemical impedance spectroscopy. The anticorrosive property was determined in a simulated corrosive environment (0.1 M NaOH and 0.5 M NaOH). The morphological analysis of the surface of both bare metal and the lignin-coated ones, before and after exposure to the corrosive environment, was recorded using atomic force microscopy (AFM), scanning electron microscopy (SEM), and energy-dispersive X-Ray spectroscopy (EDX). The lignin showed maximum inhibition efficiency at 600 ppm in 0.5 M NaOH solution. Moreover, the lignin coated on carbon steel exhibited about 70% corrosion inhibition efficiency as recorded by potentiodynamic polarization studies and electrochemical impedance spectroscopy. The AFM and SEM analyses further corroborated the protection of the metal surface from corrosion when coated with lignin. Hence, the study suggests lignin from termite frass as a sustainable biological source suitable for anticorrosive applications. Graphic abstract

Composite Materials from Renewable Resources as Sustainable Corrosion Protection Coatings

“…Recently, lignin was investigated as potential filler for different anticorrosion coatings, demonstrating a promising inhibition potential in aggressive media [13][14][15]. Moreover, lignin represents the second natural organic material in terms of occurrence and recent technological development made it available on industrial scale employing industrial waste.…”

Lignin Phosphate: A Biobased Substitute for Zinc Phosphate in Corrosion-Inhibiting Coatings

“…In this search, researchers worldwide directed their efforts toward developing corrosion inhibitors that are biobased and relatively more compatible with ecological systems . Biobased corrosion inhibitors have been the subject of research, with significant investigations focusing on plant extracts, heterocyclic biomolecules, tannin, and lignin, − either in their natural form or after modification for potential utilization. Among the above, lignin, derived as a byproduct from the pulp and paper industry, has emerged as a notable yet unexplored candidate for corrosion inhibition.…”

Preparation of Renewable Thiol‐Yne “Click” Networks Based on Fractionated Lignin for Anticorrosive Protective Film Applications

“…There are some state-of-the-art examples where lignin was incorporated in protective, anticorrosive coatings. Lignin can become part of the coating formulation in multiple ways, including being part of the cross-linked thermoset composition, [12][13][14][15] as an additive in a thermoplastic system, [16,17] deposited on the metal surface as such, [18,19] or lignin can be used as an anticorrosive additive. [20] In this research, lignin is incorporated in the coating formulation as a component of the thermoset resin, and for that reason, only the examples of works where lignin is a part of the thermoset resin are further described.…”