Determination of gold at the ultratrace level in natural waters
โ Scribed by R. Cidu; L. Fanfani; P. Shand; W.M. Edmunds; L. Van't dack; R. Gijbels
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 855 KB
- Volume
- 296
- Category
- Article
- ISSN
- 0003-2670
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โฆ Synopsis
Several methods for the preconcentration of dissolved gold in natural waters were evaluated for use with graphite furnace atomic absorption spectroscopy (GFAAS) or inductively coupled plasma mass spectrometry (ICP-MS). An anion exchange method prior to GFAAS, and a solvent extraction method prior to ICP-MS both proved to have similar recoveries, Iow limits of detection (0.4 and 0.2 ng l-l, respectively, for a 2-l sample) and good reproducibility. Parallel analyses of particulate gold were also carried out by instrumental neutron activation analysis (IN&Q with detection limits between 0.04 and 0.5 ng I-' depending on the volume of filtered water, to provide a complete evaluation of transported gold. These methods were subsequently tested on stream, spring and adit water samples, to check the accuracy of methods for natural waters. Results obtained by ICP-MS and GFAAS on natural water samples were comparable. The maximum dissolved gold concentration was 3 ng I-', and particulate gold formed less than 50% of the total amount of gold transported. No significant variation was found in the dissolved gold content of one spring water sample monitored monthly over a one year period.
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