Alloxazine (ALLO) was studied as an effective corrosion inhibitor for mild steel in 1 M HCl solution using UV-visible spectrophotometric and gravimetric technique at 303 – 333 K. The results indicate that alloxazine inhibited the corrosion process in acid medium by virtue of adsorption. Inhibition efficiency improved with concentration but decreased with rise in temperature. Temkin adsorption isotherm was found to provide an accurate description of the adsorption behaviour of the alloxazine. The mechanism of physical adsorption is proposed from the values of Ea and ΔGoads obtained. The UV-Visible spectroscopy study provides a strong evidence for the possibility of the formation of a complex between Fe2+ cation and the studied inhibitor in 1 M HCl solution which may be responsible for the observed inhibition. Computational simulation was performed on the molecular structure of alloxazine to give further insight into the inhibitory action of the inhibitor.
