Vol. 1, Issue 8, Part F (2015)

Abstract
Corrosion inhibitory effect of 2-{(3-nitrobenzylidene)amino}phenol (SBNAP) Schiff base on mild steel and aluminium in Sulphuric acid media were investigated by weight loss and gasometric methods at a temperature range of 30 °C – 50 °C. The results showed that the inhibition efficiency of SBNAP for mild steel increased with increase in temperature while that of aluminium decreased as the temperature increased. The plots of log (wi - ∆w) against time gave linear graphs which confirmed a first order reaction mechanism for both metals. The inhibition efficiency of 34.98% at 1.0x10-2 M concentration for mild steel was obtained while that obtained for aluminium was 63.81% at 30 oC. The positive values of the heat of adsorption, entropy of adsorption and the negative free energies of adsorption suggest an endothermic reaction, a disordered system and spontaneous adsorption of the studied Schiff base on the metals surface respectively. The values of the average activation energies and free energies of adsorption support physisorption reaction mechanism.