Abstract
The inhibition effect of three compounds of bidentate azo dyes of 1-(4-aminophenyl) propan-1-one toward the corrosion of aluminum in 0.1 M NaOH solution was studied using weight loss and galvanostatic polarization measurements. The percentage inhibition efficiency was found to increase with increasing the concentration of inhibitors, decreasing the temperature and the presence of the electron-donating groups in the chemical structure of inhibitors. The inhibiting effect of the investigated compounds is due to its adsorption on the aluminum surface. The adsorption obeys Temkin isotherm. The polarization data showed that the bidentate azo dyes compounds act as mixed type -inhibitors. The addition of Mg2+, Ca2+ and Ba2+ ions to the additives enhanced the inhibition efficiency due to synergistic effect. Some activated thermodynamic parameters were computed and explained.