학술논문

A comparison of sequential extraction techniques for determining arsenic fractionation in synthetic mineral mixtures.
Document Type
Article
Source
Analytical & Bioanalytical Chemistry. Oct2003, Vol. 377 Issue 4, p723-729. 7p.
Subject
*EXTRACTION (Chemistry)
*EXTRACTION techniques
*ARSENIC compounds
*ORE deposits
*CALCIUM
*GOETHITE
Language
ISSN
1618-2642
Abstract
The sequential extraction methods according to Tessier et al. [1], Borovec et al. [2], Zhang and Moore [3] and Hall et al. [4] have been tested for their suitability for arsenic fractionation in samples of artificially prepared mineral mixtures. Mixtures containing different amounts of As-containing phases were prepared so that their compositions corresponded to weathering products on As-bearing ore deposits. A comparison of different procedures on simple mineral mixtures containing calcium arsenate (CaHAsO4·H2O), As-bearing goethite (FeOOH) and arsenopyrite (FeAsS) showed that only the results of the Hall method satisfactorily correspond to the expected arsenic distribution. A detailed verification of the Hall method was subsequently carried out on most complex synthetic mineral mixtures with varying amounts of As-containing kaolinite and carbonate, calcium arsenate, As-bearing goethite and arsenopyrite. The results confirm that the Hall method cannot be fully employed for an accurate As speciation but may be applied for a route identification of As distribution between "labile", "medium-labile" and "residual" forms in heavily polluted soils. [ABSTRACT FROM AUTHOR]