Abstract: The weight loss method has been used to study the corrosion inhibitory properties of Schiff bases (LPYA and LPHA) on Mild Steel Corrosion in 0.5M HCl. Maximum inhibition efficiency was obtained at an optimum concentration of 1.0×10-2M and highest temperature of 353K for both Schiff bases. A higher inhibition efficiency of 99.30% was obtained for LPYA while 77.01% for LPHA at the same temperature and concentration. However an increase in temperature increased the inhibition efficiencies of both Schiff bases. The phenomenon of chemical adsorption has been proposed for both Schiff bases since an increase in temperature showed a corresponding increase in their inhibition efficiency.

Keywords: Corrosion; Inhibition; Mild steel; Temperature; N–{[-2 Pyridine–2–azo)–5–Hydroxyl] Phenyl}–4–Methoxybenzilidenimine (LPYA); N–{[2–(3–hydroxyphenylazo)–5–hydroxyl] phenyl}–4–methoxy benzilidene (LPHA).