Hybrid liquid membrane — Electrodialysis process for extraction of manganese(II)

A novel method of manganese(II) extraction from sulphuric acid solutions is proposed. The method involves electrodialysis through bulk liquid membranes containing di(2-ethylhexyl)phosphoric acid and tri-n-octylamine in 1,2-dichloroethane. The effects of the main electrodialysis parameters as well as of the composition of the liquid membranes and aqueous solutions on the manganese(II) transport rate are determined. It is demonstrated that a practically complete removal of Mn(II) from the feed solution containing 0.01 mol/L of MnSO4 is achieved during 0.5–2.0 h of electrodialysis. Maximum stripping degree of 88% is obtained under optimal conditions. It is shown that the liquid membranes ensure an effective one-stage extraction of manganese(II) into diluted solutions of sulphuric, nitric, hydrochloric, perchloric acids and water.

Research highlights
► Galvanostatic electrodialysis through bulk liquid membrane.
► Complete one-stage removal of manganese(II) from 0.01 mol/L MnSO4 solution.
► Maximum stripping degree of 88%.
► Extraction of Mn(II) into 0.1 M solutions of HCl, H2SO4, HNO3, HClO4 and water.
► The effects of the experimental conditions are determined.