Effect of diphenylthiocarbazone and diphenylcarbazone on acid corrosion of aluminium in HCl solution - Part 1

The inhibitory effect of diphenylthiocarbazone (DPTC) and diphenyl carbazone (DPC) on acid corrosion of aluminium 2S alloy in 0.5 M HCI has been investigated using chemical technique. DPTC and DPC have moderate inhibitory effects on the corrosion of aluminium in HCl solution. The protection efficiency increases with increasing concentration of the compounds. DPTC exhibits higher maximum inhibition efficiency than DPC. The difference in the inhibition behaviour of the compounds is explained on the basis of the difference in election donor ability of the sulphur and oxygen atoms. The adsorption of the compounds via their adsorption centers on the aluminium surface obeyed the Langmuir adsorption isotherm. The ΔG0 ads values were calculated using thermodynamic equations