Simultaneous Determination of Volatile Metal (Pb, Hg, Sn, In, Ga) and Nonmetal Species (Se, P, As) in Different Atmospheres by Cryofocusing and Detection by ICPMS
Résumé
A sensitive method for multielemental speciation analysis of volatile metal and metalloid compounds in air has been developed. The analytes are sampled simultaneously in the field by cryofocusing on a small glass wool-packed column at -175°C. Detection is performed in the laboratory by low-temperature GC hyphenated with ICPMS. Oxygen addition in the carrier gas was used to reduce interferences originating from the presence of volatile carbon-containing species in the samples. Plasma stability during analysis was monitored continuously by internal standardization (Xe). This system provides routine absolute detection limits of 0.06-0.07 pg (as Pb) for tetraalkyllead species (Me4Pb, Et4Pb), 0.2 pg (as Sn) for tetraalkyltin species (Me4Sn, Et4Sn), 0.8 pg (as Hg) for mercury species (Hg0, Me2Hg, Et2Hg), and 2.5 pg (as Se) for selenium species (Me2Se). This instrumentation makes it possible to collect small air sample volumes and has been successfully applied to the determination of volatile metal and metalloid species in the atmosphere in urban and rural locations. Qualitative application in the semiconductor industry is also reported with regard to the detection of arsenic (ASH3, tert-butylarsine), phosphorus (PH3, tert-butylphosphine), alkylindium, and gallium species.