Kinetic study of atomization in atomic absorption analysis of solid samples using flame-furnace atomizer

Abstract

Abstract:© Versita Sp. z o.o. Direct solid sampling analysis in atomic absorption spectrometry using flame-furnace atomizer allows to significantly decrease analysis duration, to avoid sample pollution and to exclude toxic reagents. The choice of chemical modifiers that decreases the detection limit and improves the repeatability of results is based on the mechanism of analyte-free atom formation. The kinetic approach developed here allows determination of pre-exponential factors k 0 and apparent activation energies E a of the atomization processes for Pb(II) and Cd(II) compounds and enables use of CaCO 3 and KHF 2 as effective chemical modifiers for soil samples. A fast and precise technique for lead and cadmium determination in soils using the proposed chemical modifiers was developed.

Atomic spectrometry update. Environmental analysis

“…Soil suspensions were spiked with 112 Cd and 206 Pb and shaken. Aliquots of the mixture removed at different times (from 1 minute to 25 days) were filtered, and their 111 Cd/ 112 Cd and 208 Pb/ 206 Pb ratios measured by ICP-MS. Amounts of isotopically exchangeable metals were compared with analyte concentrations in conventional single and sequential extracts.…”

“…The potential usefulness of LA-ICP-MS in environmental forensics 238 was highlighted in a study of soils and sediment; data obtained correlated well at the 95% confidence interval with results from ICP-AES and ICP-MS. The use of standards prepared in CaCO 3 and normalisation of the 208 Pb signal to 42 Ca allowed Pb pollution in coral to be measured. 239 A novel DGT gel 240 based on precipitated ferrihydrite had greater stability and higher P binding capacity than gels previously available.…”

“…Although protocols for U-Pb dating of zircons are well established, there are still significant challenges in the dating of apatite by LA-ICP-MS. Chew et al 334 assessed methods for correcting for both the presence of ''common Pb'' and the occurrence of laser-induced fractionation when determining U-Pb and Th-Pb ages of apatites. Mathematical corrections based on either 207 Pb or 208 Pb were the most suitable for dating single grain detrital apatites. Laser-induced Pb/U fractionation was relatively minor and easily corrected for by using the backcalculated intercept of the time-resolved signal.…”

“…Isotopic fractionation at the ablation site posed no limitation on accuracy provided the ablation was well controlled. The external precision of ablation of NIST SRM 610 (Trace Elements in Glass) with a 60 mm beam was AE0.011% (2SD, relative) for 208 Pb/ 206 Pb and 207 Pb/ 206 Pb, whereas inclusionto-inclusion reproducibilities for the same ratios were AE0.05% (2SD, n ¼ 11); each inclusion contained ca. 1 ng Pb.…”