Cd(II) extraction in PEG-based two-phase aqueous systems in the presence of iodide ions. Analysis of PEG-rich solid phases

• Authors: Laura Bulgariu , Dumitru Bulgariu , Ioan Sârghie , Theodor Măluṭan
• Languages of publication: EN

Abstracts

EN

Cd(II) plus iodide species were extracted into PEG-rich phases in the aqueous PEG(1550)-(NH4)2SO4 system at pH 2.05–7.12. IR spectra show that increasing (NH4)2SO4 solution acidity does not protonate PEG ether oxygen atoms, but decreases water content in the PEG-rich phases. Metallic species’ extraction into the PEG predominantly alters how water molecules bind to polymer chains; the changes in their absorption bands depend on pH. Microscopy shows that “fixation” of the extracted metal in the PEG-rich phase occurs by specific interactions which depend on the species. These also determine changes in the polymer chains’ conformation.

Keywords

EN

Aqueous two-phase system; Cd(II) extraction; iodide ions; solidified PEG-rich phases; IR spectrometry; optical microscopy; PEG extraction

• Publisher: De Gruyter Open
• Journal: Open Chemistry
• Year: 2007
• Volume: 5
• Issue: 1
• Pages: 291-302

Dates

published

1 - 3 - 2007

online

1 - 3 - 2007

Contributors

author

Laura Bulgariu

• Department of Analytical Chemistry, Faculty of Chemical Engineering, Technical University “Gh. Asachi”, 700050, Iaşi, Romania

author

Dumitru Bulgariu

• Department of Geology — Geochemistry, Faculty of Geography and Geology, “Al. I. Cuza” University, 700050, Iaşi, Romania

author

Ioan Sârghie

• Department of Analytical Chemistry, Faculty of Chemical Engineering, Technical University “Gh. Asachi”, 700050, Iaşi, Romania

author

Theodor Măluṭan

• Department of Natural and Synthetic Polymers, Faculty of Chemical Engineering, Technical University “Gh. Asachi”, 700050, Iaşi, Romania

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Identifiers

DOI

10.2478/s11532-006-0048-7