Application of pseudo-emulsion based hollow fiber strip dispersion with task-specific ionic liquids for recovery of zinc(II) from chloride solutions

Abstract

Task-specific ionic liquids: 3-[1-(hydroxyimine)undecyl]-1-propylpyridinium bromide and 3-[1-(hydroxyimine)undecyl]-1-propylpyridinium chloride as the carriers in the Zn(II) extraction from chloride media through pseudo-emulsion based membrane strip dispersion (PEHFSD) have been presented. The transport of zinc(II) was investigated as a function of various experimental variables: flow rates of phases, ionic liquid structure in the organic phase, initial zinc(II) concentration and chloride ions in the feed phase. The overall mass transfer coefficient of permeation was calculated from the experimental data, the values being found in the range of 2.5×10−7–8.0 × 10−7 m/s. The recovery of Zn(II) by the stripping solution (5% w/v Na2SO4) was around 70% for most conditions tested. The results of using the task-specific ionic liquids as carrier were also compared to that obtained using the commercial extractant tributyl phosphate.