SYNTHESIS AND COMPARATIVE STUDY OF THE INHIBITIVE PROPERTIES OF ISOMERIC SCHIFF BASES AND ITS CYCLISATION PRODUCTS

Abstract

The corrosion behaviour of mild steel in 1M sulphuric acid solution and its inhibition by Schiff bases and thiazolidinones was studied using weight loss method at various temperatures (303-333K), by electrochemical and non - electrochemical techniques. The percentage inhibition efficiency of the inhibitors increased with increase in inhibitor concentration. Potentiodynamic polarization studies revealed that though the Schiff bases and thiazolidinones act as mixed type inhibitors they are slightly anodic in nature. Adsorption of these inhibitors on the mild steel surface followed the Langmuir adsorption isotherm. The thermodynamic parameters such as activation energy (Ea) and free energy of adsorption (ΔG°ads) were calculated. The synergistic effect of halide ions on the inhibition efficiency of thiazolidinones was also studied.