Hydroxo-complexes formation in Al[3+] – Mn[2+] – NO[3]{-} – H[2]O system

Abstract

The hydrolysis process in Al3+ – Mn2+ – NO3 – – H2O system has been studied by potentiometric titration and dialysis methods. The experimental data have been obtained under the following conditions: metal ions concentration – 0.01 mol/l, molar ratio Al3+ : Mn2+ = 1 : 1, ionic strength – 0.3 mol/l (NaNO3), temperature – (25 ± 0.1) °C, pH-range – 1.7–4.0. The distribution of different Al (III) and Mn (II) forms depending upon pH value of the solution in the sphere preceding hydroxidic precipitatin fall out has been calculated. It has been established that ions Al (III) form homopolynuclear hydroxocomplexes. Heteropolynuclear hydroxo-complexes of Al (III) and Mn (II) have not been found.