Inhibition of corrosion of commercial mild steel in presence of tetrazole derivatives in acid medium

The inhibitive influence of tetrazole derivatives namely, 1-(9(1)-acridinyl)-5-(4'-aminophenyl) tetrazole, 1-(9'-acridinyl)-5-(4'-hydroxy phenyl) tetrazole and 1-(9'-acridinyl)-5-(4'-chlorophenyl) tetrazole on the corrosion of commercial mild steel in I N hydrochloric acid medium was studied by weight loss method. The monolayer adsorption has been confirmed by fitting the data to the Langmuir adsorption isotherm. Weight loss studies have been carried out at 303K, 318K and 333K. Thermodynamic parameters like heat of adsorption, activation energy and free energy change have been calculated. The maximum inhibition of efficiency of tetrazole derivatives, 1-(9'-acridinyl)-5-(4'-amoinophenyl) tetrazole, 1-(9' acridinyl)-5-(4'-hydroxyphenyl) tetrazole and 1-(9'-acridinyl)-5-(4'-Chlorphenyl) tetrazole was found to be 60.59%, 89.00% and 92.74, respectively.