Branched poly(ethylene imine) support for resins with retention properties for heavy metal ions

A crosslinked poly(ethylene imine), using epichlorohydrin as crosslinker, was prepared and subsequently modified in order to obtain the corresponding N-methylated, N-carboxymethylated and N-phosphonomethylated derivatives. The sorption characteristics of these functionalized resins were studied by a batch equilibration technique, for uptake of Cu(II), Fe(II), Fe(III) and uranyl ions from aqueous solution. Resins with tertiary amine or ammonium groups show negligible sorption for Fe(II), Fe(III) and Cu(II) at pH 1, in contrast with high sorption for U(VI), which is readily eluted with sodium carbonate.