2 research outputs found
Improvement approaches for the determination of Cr(VI), Cd(II), Pd(II) and Pt(IV) contained in aqueous samples by conventional XRF instrumentation
This work was aimed to achieve improved instrumental sensitivity and detection limits for the determination of several
elements (Cr (VI), Cd, Pd and Pt) in liquid samples by using conventional energy dispersive x-ray fluorescence (EDXRF) and
wavelength dispersive x-ray fluorescence (WDXRF) instrumentation. In all cases, the preconcentration of metals from liquid
solutions was performed by using membranes activated with the commercial anionic exchanger Aliquat 336 (a quaternary
ammonium salt), which also permits the isolation of Cr (VI) species for further x-ray fluorescence analysis. Likewise, for the
improvement of the instrumental sensitivity, a special sample holder device was used in the case of Cd determination by
EDXRF (tungsten x-ray source) instrumentation. ForWDXRF analysis, the spectral evaluation was carried out by the integration
of the peak area (using WinQXAS software) instead of the common net peak line intensity traditionally used in conventional
WDXRF systems.With the proposed methodologies, a linear response between themetal present in the aqueous solutions and
the metal extracted in the membranes was obtained, highlighting the feasibility of using these membranes as standards for
x-ray fluorescence spectrometry (XRF) analysis for future determination of these elements when contained in liquid samples.
Concerning the calculated detection limits, in all cases, theywere in the ÎŒg lâ1 range, indicating the possibilities of the proposed
methodology for trace determination content of Cd, Cr(VI), Pd and Pt in liquid solutions using conventional EDXRF andWDXRF
instrumentation.This study was financed by the Spanish National Research
Programme (projects CGL2007-66861-C04 and Consolider Tragua,
ref. CSD2006-00044).Peer reviewe