Selective recovery of Cu(II) through polymer inclusion membranes mediated with 2-aminomethylpyridine derivatives

The Cu(II) separation behaviors with polymer inclusion membranes (PIMs) are explored by modifying 2-aminomethylpyridine derivatives with hydrophobic alkyl chains, including 2-[N-(tert-butyloxycarbonylmethyl)-2-picolyamino]acetate (AMB), N,N-dioctyl-2-aminomethylpyridine (AMD), tert-butyl 2-(N-octyl-2-picolyamino) acetate (AMC), and N,N-didecyl-2-aminomethylpyridine (AME). The transport flux and selectivity of Cu(II) are determined by optimizing composition and structure of carriers and plasticizers. The results show that the hydrophobic modification of 2-aminomethylpyridine derivatives can boost the selective transport of copper ions in PIMs and membrane stability. In the optimum composition of 30 wt.% PVC, 30 wt.% AME, and 40 wt.% NPOE, the initial flux of Cu(II) is 5.8 x 10(-6) mol m(2) s(-1). The FT-IR and XPS spectra identify that the alkyl amine functional groups of AME involve in the transport of copper chloride species. The SAXS analysis demonstrates that the generated micro-channels in PIMs induced by the hydrophobic modification of 2-aminomethylpyridine derivatives can contribute to the enhanced Cu(II) flux.

Automated summary

The study focuses on the Cu(II) separation behaviors using polymer inclusion membranes (PIMs) modified with hydrophobic alkyl chains. Through optimizing the composition and structure of carriers and plasticizers, the selective transport of Cu(II) in PIMs was significantly enhanced. In the optimal composition, the initial flux of Cu(II) reached 5.8 x 10(-6) mol m(2) s(-1), showing promising potential for practical applications in metal separations.