Sorption of metal ions on a weak acid cation-exchange resin containing carboxylic groups

✍ Scribed by Maria Pesavento; Raffaela Biesuz; José Louis Cortina

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 905 KB
• Volume: 298
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(94)00271-1

✦ Synopsis

The sorption properties of a commercial resin containing a carboxylic active group, Amberlite@ CG-SO, for magnesium, calcium, copper and zinc were investigated on the basis af the Donnan model. It is assumed that the main driving force for the sorption of divalent metal ions is the complexation by the carboxylic groups inside the resin. Under typical batch conditions bg~ excess ~2 ligan& only the 1: 2 complexes are formed for all metal ions considered, whereas in aqueous solution only I : Z cempkxes are reported for calcium and magnesium and the monomeric analogues of tk active group of Amberlite@ CC-50. The intrinsic complexation constants obtained from the batch experiments agree well with those in aqueous solutian. The same holds for the intrinsic complexation constant evaluated from chromatographic experiments. This confirms some previous results obtained with a chelating resin containing an iminodiacetic group, Chelex 100. The values of the complexation constants for the carboxylic groups found with Chelex 300 are in agreement with those found with Amberlite@ CG-$0,