The use of the steric effect of the carrier molecule in the polymer inclusion membranes for the separation of cobalt(II), nickel(II), copper(II), and zinc(II) ions

Abstract

In this study, palladium-modifi ed nickel foam substrate was applied to examine ethanol oxidation reaction (EOR) in 0.1 The transport of cobalt(II), nickel(II), copper(II), and zinc(II) ions from chloride solutions across polymer inclusion membranes (PIMs), which 1-heptylimidazole (1) or 1-heptyl-2-methylimidazole (2) or 1-heptyl-4-methylimidazole (3) as the ion carrier was reported. The steric effect for carriers 2 and 3 decreases the transport of all ions except Cu(II). The initial fl uxes of metal ions transport across PIMs with the 1 -2 decrease in the sequence: Cu(II) > Zn(II) > Co(II) > Ni(II), whereas for 3 they were Cu(II) > Zn(II) > Ni(II) > Co(II). The highest recovery values were obtained for Cu(II), this being 99 and 85% for carrier 1 and 2, respectively. In both membranes the degree of deposition of the Zn(II) ions was comparable. Zn(II), Co(II) and Cd(II) ions, which form complexes with coordination numbers 4 and 6, are more easily recovered with the use of carriers 2 and 3. Ni(II) ions, which form complexes with coordination number 6 only, practically remain in the feeding phase. PIMs with alkylimidazoles were characterized by non-contact atomic force microscopy.

Application of Polymer Inclusion Membranes Doped with Alkylimidazole to Separation of Silver and Zinc Ions from Model Solutions and after Battery Leaching

“…The roughness of the obtained membranes was lower than the roughness of the CTA membrane obtained by Tor et al, which was 14 nm [57]. The microstructure of the membrane (roughness [42,57,58], porosity [32,59], and tortuosity [56]) has an impact on the transport. The darker areas in the AFM images (Figure 3) show elongated pores (cavity channels), which may indicate the crystallization of carrier molecules inside the CTA.…”

“…The roughness of the obtained membranes was lower than the roughness of the CTA membrane obtained by Tor et al, which was 14 nm [ 57 ]. The microstructure of the membrane (roughness [ 42 , 57 , 58 ], porosity [ 32 , 59 ], and tortuosity [ 56 ]) has an impact on the transport.…”

“…1-alkylimidazole (alkyl—from hexyl to decyl) were used for Cu separation from a Cu–Zn–Co–Ni mixture from nitrate [ 41 , 42 ] or chloride solutions [ 43 ], and for Zn separation from Zn–Co–Ni [ 44 ], Zn–Cd–Ni [ 45 ], and Zn–Mn mixtures [ 46 ]. 1-vinylimidazole was used to separate Cu(II) and Fe(III) ions during transport across polyvinyl acetate membranes [ 47 ].…”

“…1-vinylimidazole was used to separate Cu(II) and Fe(III) ions during transport across polyvinyl acetate membranes [ 47 ]. 1-alkyl-2-methylimidazole (alkyl—from hexyl to octyl, and decyl) was used for Cu separation from a Cu–Zn–Co–Ni mixture [ 42 , 48 , 49 , 50 ], as well for Zn separation from a Zn–Cd–Ni mixture [ 45 ]. Separation of Zn from a Zn–Cd [ 51 ] or a Zn–Mn [ 45 ] mixture is also possible using alkyl imidazole derivatives.…”

Statistical analysis and optimal design of polymer inclusion membrane for water treatment by Co(II) removal

“…The developed mixed solution was poured into a membrane mold, comprising a 9.0-cm glass ring attached to a glass plate with CTA-dichloromethane glue to allow the solvent to be evaporated overnight, gradually (for 12 h). In the last step, the casted membrane was immersed in the cold double distilled water and then, separated from the glass plate by cutting its surroundings [33]. After that, the separated membrane was soaked in the aqueous solution of 0.1 mol L -1 HCl for 12 h. Finally, the PIM was stored in the distilled water for next applications.…”