Lab tour

InstrumentSpecificities
HPLC VARIAN + AFS EXCALIBUR PSA : ultra-low analysis of arsenic, selenium and antimony in solution, and their speciation

An AFS dedicated to mercury also exist

 Glovebox Jacomex XXXX

(PO2 and PCO2 <1 ppm)

 Centrifugeuse BECKMAN Avanti J-20
Integrated Combustion Module-CRDS for Bulk 13C Isotope Analysis, coupled to an oven for solid (e.g. carbonates) combustion

d13C precision < 0.03° :°°

 COT-meter SHIMADZU TOC-VCNV :
DOC, DIC and N analysis
 ICP-OES Perkin Elmer OPTIMA 3300 DV
Cation total concentration measurement
(d.l. = 10 ppb)

For As : coupling with HPLC gives arsenic LOD of approximately 5ppb for arsenite, 50 ppb for arsenate. LOQs are maybe 15 ppb and 100 ppb. We can separate MMA, DMA, AsIII and AsV well in approximately 5 minutes

 Atomic absorption AMA 254

Total Hg concentrations ([HgT]) are determined by atomic absorption spectrophotometry after 63µm grinding, dry mineralization and gold amalgamation with an automatic mercury analyzer (Altec, Model AMA 254) with a relative precision of ± 10 % (Roos-Barraclough et al., 2002). Concentrations obtained for repeated analyses of certified reference materials (CRM) never exceed the range of concentration given for standards CRM 7002 (0.09 ± 0.012 µg g-1) and MESS-3 (0.091 ± 0.008 µg g-1). The analytical quality is assured by analyzing every sample twice. The measurement error is usually about 5% and always below 10%. The detection limit (defined as three times the standard deviation (SD) of the blank) was 0.005 µg g-1.

 Spectrophotomètre UV-Visible PERKIN ELMER Lamba 35 : gamme 190 à 1100 nm
 Gas Chromatography PERKIN ELMER Clarus 500

Hydrogene (and other gases) analysis with catharometer detector

Linked to reactors allowing kinetics measurements

Tekran CV-AFS for Mercury analysis

Samples are analyzed for [(HgT)D] and [(HgT)P], [(MMHg)D] and [(MMHg)P] by cold vapor atomic fluorescence spectrometry (CVAFS) after conversion of all mercury species into Hg0 (Bloom and Fitzgerald, 1988) followed by detection using a Tekran® (Model 2500) mercury detector. The principles of the methods used are from the Bloom and Fitzgerald (1988) gold amalgamation method for (HgT)D, from the Liang et al. (1994) ethylation method for (MMHg)P and the Tseng et al. (1998) hydruration method for (MMHg)D modified by Cossa et al. (Cossa et al., 2009). (HgT)P was performed after HCl/HNO3 digestion in PFA Teflon reactors (10h at 70°C) (Coquery et al., 1997). The detailed procedures are described elsewhere (Cossa et al., 2002 ; Cossa et al., 2003). These quantifications were performed after checking for possible interference with the internal spikes (Coquery et al., 2003). The analyses accuracy was checked using the CRM ORMS-3 (National Research Council of Canada) for (HgT)D, CRM 7002 for (HgT)P and CRM ERM-AE670 (IRMM - European Commission) for (MMHg)D and (MMHg)P. The analytical quality was assured by triplicating several samples, and the measurement error was usually about 10 % and always better than 15% for [(HgT)D], [(HgT)P], and [(MMHg)D] ; and always better than 30 % for [(MMHg)P]. The detection limits (3SDblk), were 0.01 ng L-1 for (HgT)D, 0.004 ng L-1 for (MMHg)D, and 0.05 ng g-1 for (MMHg)P.