Liquid-phase polymer-based retention — the separation of metals by ultrafiltration on polychelatogens

Abstract

The importance of trace-element analysis in geological, biological, environmental and industrial processes has been increasingly recognized. Although modern instrumental methods of analysis have been applied, preliminary enrichment techniques are required to separate the components to be determined from the interfering constituents of the sample1,2. For the separation of inorganic ions contained in natural waters, industrial fluids or dissolved solid materials, solvent extraction, sorption, ion exchange, precipitation and other methods have been used. However, techniques based on a two-phase distribution or on heterogeneous reactions often cause problems because, in contrast with homogeneous reactions, diffusion controlled processes must be used. Until now, no simple, rapid method has been available for the preconcentration and separation of metals in the homogeneous aqueous phase. Here we demonstrate a technique for the enrichment and separation of metals in aqueous solution using soluble non-crosslinked polymers with chelating groups (polychelatogens)3,4 called liquid-phase polymer-based retention (LPR).