Salicylideneaniline as inhibitor for the corrosion of mild steel in 1.0 N hydrochloric acid

T. Umasankareswari and T. Jeya

Abstract

The inhibitive influence of salicylideneaniline on the corrosion of mild steel in 1.0 N hydrochloric a cid was studied by weight loss method and polarization measurements . The values of percentage inhibition efficiency, d etermined by these methods, showed close agreements. The corrosi on decreased with increasing addition of salicylide neaniline probably due to the progressive adsorption of the i nhibitor on the metal surface. The maximum inhibiti on efficiency was found to be 39.71%. The inhibition process was tested for Langmuir adsorption isotherm, kinetic thermodynamic modal of El-Awady et al. Temkin and Flory-Huggins isotherms. The best fit isotherm was the isotherm of El-Awady et al, The phenomenon of phys isorption was proposed for the process of inhibitio n. The open circuit potential of mild steel in 1.0 N HCl, in th e presence of the inhibitor of varying concentratio ns, did not show any significant shift in its values. The polarizati on studies revealed that the corrosion of mild stee l in 1.0 N HCl was predominantly under anodic control, in the presence as well as in the absence of the inhibitor. The na ture of inhibition was found to be of mixed type.

Relevant Publications in Journal of Chemical and Pharmaceutical Research