Polymerisation of β-cyclodextrin with succinic anhydride.: Synthesis, characterisation, and ion flotation of transition metals

beta-Cyclodextrin (beta-CD) polymers were prepared by cross-linking beta-CD with succinic anhydride (SA) in anhydrous N,N-dimethylformamide (DMF) in the presence of NaH. The weight-average molecular weight (M-w) and the chemical structure of the polymers were determined using high performance size exclusion chromatography (HPSEC) with refractive index (RI) detector, and H-1 NMR spectroscopy. The molecular weight of the polymer increased with reaction temperature. H-1 NMR spectra revealed that the CD polymers contained both mono- and diesters of butanodioic acid. In the case of fractions with higher molecular weight, about two diester moieties groups are linkages for CD molecules. Results of competitive ion flotation of copper(II) obtained with the use of nonylphenol polyoxyethyl glycol ether as an non-anionic surfactant and beta-CD polymers as complexation agent, show that the removal of metal decreases with higher molecular mass of beta-CD polymers. The competitive ion flotation of Cu2+, Zn2+, and Cd2+ cations from diluted aqueous solutions in the presence beta-CD polymers is presented. (C) 2004 Elsevier Ltd. All rights reserved.