The Electrocapillary Behaviour and the Corrosion-Inhibitive Nature of some Organic Sulphur Compounds

The effects of different organic radicals attached to the sulphide group in dimethyl sulphide,di-n-butyl sulphide, di-phenyl sulphide and thiophene on their electrocapillary behaviour with mercury surface and on their corrosion inhibitive nature with respect to steel in 1N sulphuric acid have been examined. It has been found that (i) there is a qualitative correlation between the electrocapillary behaviour and corrosion inhibitive effect of only some of these sulphides, (ii) the inductive effect of methyl groups enhances the effectiveness of the sulphur atom both in its adsorption on mercury surface and in corrosion- inhibition and (iii) the direct linkage of the sulphur atom to aromatic groups or its incorporation in the aromatic ring brings down the electrocapillary adsorption and the corrosion inhibitive effects of the organic sulphides.