Gas Chromatography with Ultraviolet Photometric Detection for Elemental Mercury Analysis

摘要

Fossil fuel combustion such as the burning of coal contributes substantially to the release of elemental mercury into the environment. Even at the parts-per-billion level, exposure of elemental mercury can potentially have a negative impact on overall human health. We introduce a facile and practical analytical approach for the direct measurement of ultra-trace level of elemental mercury by combining the great separation power of gas chromatography with the highly sensitive and selective detection garnered from ultraviolet photometric detection approach. An inert sample flow path that utilizes surface deactivated tubing using the latest innovations in chemical vapor deposition chemistry was employed to prevent analyte adsorption for the highest degree of system inertness. Even without sample enrichment and a sample size of less than 1 mL, elemental mercury in various gas matrices can be directly measured with a detection limit of 1.7 ug per cubic metre. A total analysis can be rendered in less than 2 min [1]. A relative precision of less than 3% was attained with a concentration of 8.3 and 83 μg per cubic metre (n=20). The analytical approach is useful and complementary to established methodologies such as cold-vapour atomic absorption or cold-vapour atomic fluorescence in the overall strategy of detecting mercury in various matrices. In this lecture, method performance and examples to illustrate the utility of the technique described will be presented.