Adsorption and oxidation of aromatic amines by metal hexacyanoferrates(II).

Interaction of aniline, p-toluidine and p-chloroaniline with nickel, cadmium and manganese hexacyanoferrates(II) has been studied. Nickel and cadmium hexacyanoferrates(II) showed maximum adsorption at neutral pH, whereas, manganese hexacyanoferrate(II) reacts with aniline, p-toluidine and p-chloroaniline forming the colored oligomers on its surface. The adsorption data obtained at neutral pH is fitted in Langmuir adsorption isotherm. The adsorption behavior of the studied aromatic amines followed the order: p-toluidine>aniline>p-chloroaniline, which is related to the basicities of the amines. Results of the present study suggest the importance of metal hexacyanoferrates(II) and metal ions in stabilization of aromatic amines during the processes of prebiotic condensation reactions.