Mercury Microwave assisted extraction

In mercury speciation studies, pressurized liquid extraction (PLE), microwave-assisted extraction (MAE), and supercritical fluid extraction (SEE) are employed [33]. In particular, methyl-mercury is extracted by the Westoo method [33,34], which consists in a leaching process with hydrochloric acid, the extraction of the metal chloride into benzene or toluene, the addition of ammonium hydroxide that converts the metal species to hydroxide and the saturation with sodium sulfate. Most of the HPLC methods reported in literature for the determination of organomercury compounds (mainly monomethyhnercury, monoethyhnercury, and monophenylmercury) are based on reversed... 

C. S. Chiou, S. J. Jiang, K. S. K. Danadurai, Determination of mercury compounds in fish by microwave-assisted extraction and liquid chromatography-vapor gener-ation-inductively coupled plasma mass spectrometry, Spectrochim. Acta, 56B (2001), 1133-1142. 

Methods involve extractions of analytes into organic solvents, as well as treatments with acidic or basic reagents. Solid-phase extraction can be used for removal and pre-concentrations of analytes in aqueous solutions. Applications of low-power focused microwave technology have been investigated as a means of dissolution, and good results have been reported for extractions of organometal-lic compounds of tin and mercury (Schmitt et al., 1996 Szpunar et al., 1996). Analyses of CRMs were used for verification. The time necessary for quantitative isolations of the analytes was greatly reduced, e.g. 24 h to 5 min. In addition, there were reductions in solvent volumes, and improvement in analyte recoveries. Some of the analytical procedures for speciation of particular elements such as mercury, described later in this chapter, include microwave-assisted sample preparation. 

Total mercury in soils can be measured by ICP-MS [330]. Mercury was extracted by using a microwave assisted flow injection system. A complexing agent and surfactant were added to eliminate the long memory effects typically observed with mercury. 

I. R. Pereiro, A. Wasik, R. -obin ski, Determination of mercury species in tish reference materials by isothermal multicapillary gas chromatography with atomic emission detection after microwave-assisted solubilization and solvent extraction, J. Anal. Atom. Spectrom., 13 (1998), 743D747. 

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