Selective extraction of vanadium(V) from sulfate solutions into a polymer inclusion membrane composed of poly(vinylidenefluoride-co-hexafluoropropylene) and Cyphos (R) IL 101

Abstract

A poly(vinylidenefluoride-co-hexafluoropropylene) (PVDF-HFP)-based PIM containing trihexyltetradecylphosphonium chloride (Cyphos® IL 101) as its carrier was developed for the selective extraction of V(V) from sulfate solutions. Various plasticizers/modifiers were tested and best results in terms of rate of extraction and amount extracted were obtained with 2-nitrophenyloctyl ether (NPOE). The optimal PIM composition, with respect to the same criteria was determined to be 35 wt% Cyphos® IL 101, 55 wt% PVDF-HFP and 10 wt% NPOE. Back-extraction of V(V) was achieved using 6 mol L−1 H2SO4. An anion exchange mechanism is proposed for the extraction of V(V) involving the formation of the complex an..