Antibacterial Corrosion Inhibitor for the Protection of Mild Steel in 1 M HCl Solution

Mild steel is widely utilised as a construction material because of its mechanical qualities and low cost but its weak acid corrosion resistance limits its application. The ability of para-chlorobenzoyl-hydrazinylmethane (P-CBHM) as a corrosion inhibitor and antibacterial agent was investigated by gravimetric measurements, density functional theory (DFT) and antibacterial studies. The weight loss results showed that the inhibition efficiency of P-CBHM to prevent the corrosion of mild steel in 1.0 M HCl increased with concentration from 100 to 500 ppm, with a maximum inhibition efficiency of 96.5 % at 500 ppm. The inhibitory action of the inhibitor was explained in terms of adsorption on the mild steel surface which follows a Langmuir isotherm via physisorption and chemisorption mechanisms. P-CBHM has significant corrosive protection efficacy and antimicrobial activity similar to the common antibacterial agent, chloramphenicol. The novelty of this work was the investigation of the protective response of P-CBHM which was analysed analytically on the corrosion of mild steel in 1.0 M hydrochloric acid using gravimetric and thermometric techniques and its antibacterial effects.