Methyl isobutyl ketone extraction of manganese(II) with ethylxanthate

Abstract

Manganese (II) ion could be extracted with methyl isobutyl ketone (MIBK) in the presence of a large excess of potassium ethylxanthate (potassium O-ethyl dithiocarbonate, Ketx). The distribution ratio of manganese, D, was affected by the factors of pH, the concentration of etx^-, and the kinds and/or concentrations of coexisting cations in the aqueous phase. Manganese (II) was extracted quantitavely under the following conditions: pH of (8.09.2), [Ketx] of 0.6 mol dm^-3 or above. The relationship between log [etx^-] and log D, gave a straight line with the slope equal to 3. Consequently, the extracted species contains manganese (II) and etx^- in the mole ratio of 1:3. The solid yellow Mn-etx complex was synthesized by the addition of a 3 mol dm^-3 solution of manganese sulfate into a 4 mol dm^-3 solution of Ketx at the temperature below 5°C. The crystal of this complex, which was recrystallized with a mixed solvent of ethanol and diethylether (1:1) had the composition of K [Mn (etx)₃], being modelately soluble in water and very soluble in MIBK. The solid complex was unstable in air. The visible absorption spectra of the MIBK solution of the synthesized complex coincided with that of the MIBK extract from the aqueous solution. From these results, the extracted species with MIBK is expected to be K [Mn (etx)₃].