No abstract

ZUSAMMENFASSUNG:Es werden mehrere SynthesemiSglichkeiten fur die Herstellung von an Cellulose immobilisierten 8-Hydroxychinolin-und 8-Hydroxychinolin-5-sulfonsaure-Derivaten beschrieben, die zu einem Produkt mit einer Kapazitat von 500-800 pmol/g, hoher Austauschgeschwindigkeit und guter Stabilitat gegenuber dem Eluenten fiihren. Die scheinbare Komplexbildungskonstante der Oxincellulosen mit Zn2+ ist etwa 2 * 1 O5 mol-' dm3. SUMMARY:Some routes to synthetize covalently bound chelating groups as 8-hydroxyquinoline or 8-hydroxyquinoline-5-sulfonic acid to cellulose are given. The products show a capacity of 500 -800 pmol/g, fast kinetics of exchange and good stability against the eluent. The apparent stability constant of the complexes with ZnZ+ are around 2 lo5 mol-' dm3.

A microprocessor controlled pre-concentration system that permits the automated off-line pre-concentration of several samples at the same time is described. Trace elements pre-concentrated f r o m sample volumes of u p to several hundred millilitres can be eluted by 5 ml of 2 M nitric acid. It is therefore possible t o achieve pre-concentration factors of up t o 100. In contrast t o FIA methods all ICP-A€ spectrometers can be used for the measurements. Four different chelating ion-exchange materials, Chelex 100, oxine cellulose, CPPl resin and Hyphan cellulose, were compared. Trace elements were enriched from concentrated salt solutions and from NBS standard reference materials following decomposition i n the High Pressure Asher. After elution the elements were measured b y ICP-AES (Plasma II) and b y graphite furnace AAS (HGA-500/Zeeman 5000). Under the conditions tested, Chelex 100, the oxine cellulose and the CPPl resin can be employed satisfactorily i n the automated pre-concentration of a number of elements.

No abstract

No abstract