N-{[2-(3-hydroxyphenylazo)-5-hydroxyl]phenyl}-4-methoxybenzilidene (LPHA) as a Corrosion Inhibitor Of Mild Steel in 0.5M Hydrochloric Acid

摘要

The corrosion inhibition of mild steel in 0.5M Hydrochloric acid by the Schiff base, N-{[2-(3-hydroxyphenylazo)-5-hydroxyl]phenyl}-4-methoxybenzilidene (LPHA) was studied using weight loss and gasometric techniques at 303K, 313K, 323K, 333K and 353K. Maximum inhibition efficiency was obtained at an optimum concentration. However increase in temperature also increased the inhibition efficiency at the temperatures studied. The inhibition action of LPHA showed the highest efficiency of 77.01% at the highest Temperatures of 353k and highest concentration of 1.0×10~(-2)M. The phenomenon of chemical adsorption was proposed since an increase in temperature shows a corresponding increase in its inhibition efficiency. The adsorption of LPHA on mild steel obeys the Langmuir adsorption isotherms in the acid environment.