Preparation of polymer inclusion membrane with sodium diethyldithiocarbamate as a carrier reagent for selective transport of zinc ions

This study reports the design of a new type of polymer inclusion membrane (PIM) for selective transport of zinc ion. Sodium diethyldithiocarbamate (NaDDTC) was incorporated in the cellulose acetate-based membrane as a carrier for Zn(II) ion. The PIMs were characterized using Fourier trans­form infrared spectroscopy, scanning electron microscopy, atomic force microscopy and contact angle measurements. The effects of parameters, including concentration of Zn(II) in the feed phase, HCl in the stripping phase and amount of NaDDTC incorporated in the membrane, on the transport of Zn(II) ion were studied. For 1 × 10-4 M of Zn(II) ion in the feed phase at pH 5.04, 96% of Zn(II) ion was transported through the PIMs prepared with 1.0 (wt%) diethyldithiocarbamate via 0.5 M HCl as a stripping phase. The diffusion of Zn(II) ions through the membrane was governed by complex for­mation between Zn(II) ion and NaDDTC in the membrane. Moreover, selective transport of Zn(II) ion was achieved in the presence of divalent metal ions involving Cu(II), Pb(II) and Ni(II). The prepared PIM provided reproducible transport efficiency, and it can be efficiently used in separation processes.