Materials Chemistry and Physics, Vol.124, No.2-3, 1155-1165, 2010
Experimental and quantum chemical characterization of the adsorption of some Schiff base compounds of phthaloyl thiocarbohydrazide on the mild steel in acid solutions
Three derivatives of 2-[2-(hydrazinecarbonothioyl)hydrazinecarbonyl]benzoic acid (IL1) have been evaluated as new corrosion inhibitors for the corrosion of mild steel in 1 M HCl solutions using weight loss polarization and electrochemical Impedance spectroscopy (EIS) techniques The adsorption of these compounds has been tested thermodynamically which was found to be of neither a typical physisorption nor a typical chemisorption mode The thermodynamic functions (such as E-a Delta H degrees(ads) Delta S degrees(ads) and Delta G degrees(ads)) of dissolution and adsorption processes have been evaluated The polarization measurements indicated that the inhibitors are of mixed type The adsorption of the compounds was found to obey Langmuir s adsorption isotherm In addition quantum chemical calculations have been made to correlate inhibition efficiencies determined experimentally (C) 2010 Elsevier B V All rights reserved