Biogenic corrosion inhibition through Bacillus coagulans on mild steel in mild acidic medium

Abstract

In the present study, the corrosion inhibition properties of Bacillus coagulans against mild steel (MS) were studied employing electrochemical procedures to monitor the real-time corrosion rate, mechanism, development of efficient mitigation strategies, and material protection. Results of the study revealed that under acidic environments B. coagulans formed a protective biofilm on MS surface and caused marked reduction in corrosion and other forms of mutilation. Characterization and electrochemical procedures were performed to investigate the inhibitory effects of B. coagulans at different pH and at different temperatures on the corrosion rate and, to determine the mechanism of corrosion prevention. The film developed on surface of the MS by B. coagulans, was crack free, compact, and lipophilic in nature and was composed of amyloid fibers, carboxylic acid, and proteins that make electrochemical reactions that, accruing on the metal–solution interface difficult and substantial reduction in corrosion rates observed. The film adhered to the surface of metal substrates shows fitting with diverse adsorption isotherm indications, with physical adsorption being the predominant pattern observed in most cases. This suggests that the interaction between the biofilm and metal surfaces is primarily governed by physical forces. To conclude, B. coagulans exhibits protective action on MS against corrosion.