Transport of Rhodium(III) from Chloride Media across a Polymer Inclusion Membrane Containing an Ionic Liquid Metal Ion Carrier

Takafumi Hanada; Mochamad Lutfi Firmansyah; Wataru Yoshida; Fukiko Kubota; Spas D Kolev; Masahiro Goto

doi:10.1021/acsomega.0c00867

Transport of Rhodium(III) from Chloride Media across a Polymer Inclusion Membrane Containing an Ionic Liquid Metal Ion Carrier

ACS Omega. 2020 May 27;5(22):12989-12995. doi: 10.1021/acsomega.0c00867. eCollection 2020 Jun 9.

Authors

Takafumi Hanada¹, Mochamad Lutfi Firmansyah², Wataru Yoshida¹, Fukiko Kubota¹, Spas D Kolev³, Masahiro Goto^{1

4}

Affiliations

¹ Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Motooka, Fukuoka 819-0395, Japan.
² Department of Chemistry, Faculty of Science and Technology, Airlangga University, Ji. Dr. Ir. H. Soekarno, Surabaya 60115, Indonesia.
³ School of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia.
⁴ Center for Future Chemistry, Kyushu University, 744 Motooka, Fukuoka 819-0395, Japan.

Abstract

Efficient and selective transport of rhodium(III) across a polymer inclusion membrane (PIM) from a 0.1 mol dm^-3 HCl feed solution, also containing iron(III), to a receiving solution containing 0.1 mol dm^-3 HCl and 4.9 mol dm^-3 NH₄Cl was achieved using a phosphonium-type ionic liquid, trioctyl(dodecyl)phosphonium chloride (P₈₈₈₁₂Cl), as the metal ion carrier. The optimum PIM composition for the Rh(III) transport was 50 wt % poly(vinylidene-co-hexafluoropropylene) (PVDF-HFP), 30 wt % P₈₈₈₁₂Cl, and 20 wt % plasticizer 2-nitrophenyl octyl ether (2NPOE). The driving force for the Rh(III) transport was suggested to be the concentration difference of the chloride ion between the feed and the receiving solutions. More than 70% rhodium(III) could be recovered from the receiving solution, and no transport of iron(III) was observed; however, the two metal ions cannot be separated by liquid-liquid extraction. This is the first report of selective transport of rhodium(III) across a polymer inclusion membrane.