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Analytical Methods for Speciation of Mercury in Gas Condensates: Critical Assessment and Recommendations

“…It was totally eliminated at temperatures as low as 125°C (Shafawi et al, 1999a). These results are in contradiction to those obtained by Tao et al (1998) Bouyssiere et al (2000). Injection temperature above 300°C was recommended for HgCl 2 due to its slow vaporization in the inlet (Tao et al, 1998).…”

“…Satisfactory resolution of dialkyl mercury species was achieved using non-polar columns but of other mercury species only MeHgCl could be eluted-nota bene: at the same retention time as Et 2 Hg (Bouyssiere et al, 2000). Broad peaks for HgCl 2 and monoalkyl mercury species, even in the oncolumn mode (Tao et al, 1998).…”

“…Non-Polar Columns Non-polar columns allow sharp peaks to be obtained for Hg°a nd dialkyl mercury species regardless of the injection mode (Tao et al, 1998;Bouyssiere et al, 2000). Satisfactory resolution of dialkyl mercury species was achieved using non-polar columns but of other mercury species only MeHgCl could be eluted-nota bene: at the same retention time as Et 2 Hg (Bouyssiere et al, 2000).…”

“…Several dialkyl species were identified in the condensates analyzed. However, the quantification carried out at the detection limits, the unusually high (up to 100% of the total mercury) proportions of alkyl mercury species found, and the fact that no alkyl mercury species were found in some of the samples run in parallel by GC-ICP MS (Bouyssiere et al, 2000) induce doubts about the validity of the coupling.…”

“…The poor selectivity of these methods and the impossibility of the unambiguous confirmation of the identity of species present is spurring the development of truly species selective methods based on the coupling of chromatography with mercury specific detection Tao et al, 1998;Shafawi et al, 1999a;Bouyssiere et al, 2000).…”