Mn (VII) ions transport by triethanolamine cyclohexanone based supported liquid membrane and recovery of Mn (II) ions from discharged zinc carbon dry battery cell

Triethanolamine (TEA) dissolved in cyclohexanone has been used as a carrier in Celgard 2500 microporous, hydrophobic, polypropylene film. The influence of TEA concentration in membrane phase, H2SO4 concentration in feed and strip solutions, FeSO4 concentration in strip solution and stirring speed has been investigated for the transport of Mn (VII) ions. The optimum conditions studied for the transport of Mn (VII) ions are 3.75 M TEA in cyclohexanone, 1.0 M H2SO4 in feed, 9.25 × 10−3 mol/dm3 FeSO4 at 0.5 M H2SO4 in strip and stirring speed at 1500 rpm. The stoichiometry of chemical reaction involved in complex formation is investigated from flux data. The complex involved in the transport of Mn (VII) ions is (C2H4OH)3NHMnO4. Applying the optimized conditions to discharged zinc carbon dry battery cell solution showed that almost all Mn (II) ions are extracted. Stability of supported liquid membrane (SLM) has also been investigated.

Research highlights▶ Triethanolamine (TEA) dissolved cyclohexanone + H2SO4 + Mn (VII), forms a complex (C2H4OH)3NHMnO4. ▶ The membrane strip interface complex dissociate due to redox reaction with Fe(II), Mn (II).