Tim Flow Injection Mercury System (FIMS) is a dedicated system that integrates flow injection mercury cold vapor generation with a very sensitive detector. The exceptional system stability and the long path measurement cell provide instrumental detection limits as low as 5 ng/L using a sample volume of 5(H) jxL.

The improved sensitivity of the FIMS permits sample dilution, therefore reducing the likelihood of an interference occurring with complex samples.

In this work, samples were digested with aqua regia using reflux conditions according to DIN method 38414. After proper dilution of the digested sample solution, Hg was measured interference-free using SiiCl2 as the reductant.

The recoveries of spiked mercury in sewage sludge samples ranged from 9ft to 100%. The method was checked by the analysis of standard reference materials. All results were in agreement with certified values. The RSD for three replicates was approximately 2% at 10 jig/L Hg level.

The sample solutions were also measured using a FIAS to generate the Hg vapor and the analytical data were collected using an AA spectrometer equipped with a D2 background corrector. The results are in agreement with those obtained using the FIMS, which demonstrates that any background absorption for these determinations was negligible.

For Free Access to the full article in PDF format click here