A combinatorial brief insight into microbe induced corrosion of galvanized steel and its alleviation with eco–friendly inhibitors

Abstract

This study primarily focused on the influence of Reullia tuberosa extract in alleviating Staphylococcus aureus, Klebsiella pneumonia, and Bacillus subtilis-induced corrosion on the metal samples. Nyquist plots and impedance investigations were carried out to warrant the nature of green inhibitors in controlling biocorrosion. The corrosion patterns in certain pitted zones revealed a strong correlation between the chemical composition of the metal surface and microbial metabolites based on analytical studies. The presence of microbial metabolites resulted in an increase in the porosity and permeability of the metallic surface, thereby altering the structural composition of the surface. The highest concentration of plant extract in inhibiting the microbial corrosion was identified to be 30 ppm in all three microbes. Weight loss of the coupons that were immersed in the control solution showed that corrosion rates went up for a short time but then went down after the inhibitor was added. The green inhibitors were able to alleviate the development of biofilm in the pitted areas. Analytical outcomes warranted that the green inhibitors successfully regulated the formation of microbial growth products. This study found that phytoconstituents in plant extracts effectively stopped corrosion from happening and also stopped microorganisms and biofilm from growing.

KEY WORDS: Microbial-induced corrosion, Biofilm, Plant extracts, Reullia tuberosa, Galvanized steel, Green inhibitors.

Bull. Chem. Soc. Ethiop. 2025, 39(5), 1001-1017.                                       

DOI: https://dx.doi.org/10.4314/bcse.v39i5.14