Digestion methods for analysis of fly ash samples by atomic absorption spectrometry

ENEA CRE Casaccia AMB/TEIN/CHIM, Via Anguillarese 301, 00060 Rome, Italy
Analytica Chimica Acta (Impact Factor: 4.51). 08/1999; 395(1-2):157-163. DOI: 10.1016/S0003-2670(99)00342-6


The efficiency of different digestion methods (six microwave decomposition methods and a wet acid digestion method) in the solubilisation of six metals (Cr, Ni, Cu, Pb, Cd, Zn), for their determination in fly ashes, was compared. Five different mineral acid mixtures and two different microwave systems were tested. The study was carried out by analyzing two highly homogenised fly ash samples (from sewage sludge and city waste incineration) provided by the Joint Research Centre of Ispra. Determinations were performed by atomic absorption spectrometry and by inductively coupled plasma atomic emission spectrometry. The analytical performance of the laboratory was evaluated using the 1633a Coal Fly Ash Standard Reference Material of National Bureau of Standards (NBS SRM 1633a).Results showed that a HNO3 microwave treatment was strong enough to solubilise metals from the considered fly ashes. Moreover, microwave methods generally provided higher release than the classical aqua regia method, whereas no significant advantage was observed using a high performance microwave unit.

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Available from: Zoltán Mester, Apr 28, 2014
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    • "A mixture of nitric acid and hydrogen peroxide is widely employed because they mineralise organic matter effectively and produce less spectral interference in ICP analyses [1]. Nitric acid has been reported to be strong enough to solubilize metals ISRN Analytical Chemistry from fly ashes [21], from soils with organic carbon content up to 38% [22], and from plant materials for environmental monitoring [23]. However, in general, plant samples require a more complete decomposition procedure due to the presence of high organic and/or silicon contents [24]. "
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    ABSTRACT: The use of normalized procedures designed for soil and sediment samples (like US-EPA 3051) to chemically prepare some kind of organic samples is a common practice in some laboratories. However, the performance of this method for other matrices has to be demonstrated. Three microwave-assisted digestion procedures with 0.5 g of sample and simplified reagents (10 mL HNO3 alone and mixtures of HNO3/HCl- and HNO3/H2O2 procedures A, B, and C, resp.) were compared for quantitative determination of 25 elements (Be, B, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Tl, Pb, Th and U) in three biological reference materials provided by NIST (mussel tissue (MT), tomato leaves (TL), and milk powder (MP)) by ICP-MS. From scaling masses (from 0.1 up to 0.9 g at 0.1 g interval) in procedure A, a linear relationship among instrumental signal and mass of digested sample could be constructed at 99% CL for most of the target analytes. The slope of this linear fit provided the estimation of sample concentration, while the ordinate in origin allowed the identification of matrix interferences which were absent in the reagent blank.
    01/2013; 2013:14 pgs.. DOI:10.1155/2013/851713
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    • "Suprapur) was added in a second stage only in the sediment digestion (adapted from Mester et al. (1999) "
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    ABSTRACT: a b s t r a c t The southern Venice lagoon has been affected by an increase of several anthropogenic activities (dockyards, harbours and marina) which have contributed to enrich sediments with metals in the recent years. The contamination of metals in the surface sediments along with their accumulation in the gastropod Nassarius reticulatus were investigated. Highest metal concentrations of Cu, Zn, Pb and Cr found in the dockyards and marina sites suggest their possible past and recent use as biocides in the antifouling paints. The enrichment factor (EF) showed highest values (EF4 10) near the dockyards, harbour and marina sediments for Cu, where the use of the antifouling tin free paints has been more relevant. High levels of metals were also found in the target gastropods. Biota-Sediment-Accumulation-Factor and correlation analyses pointed out a significant mobilization of metals, particularly Cu, from sediments and their accumulation in the gastropods.
    Continental Shelf Research 08/2012; 45(dx.doi.org/10.1016/j.csr.2012.05.017). DOI:10.1016/j.csr.2012.05.017 · 1.89 Impact Factor
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    • "The best one for these materials seems to be the mineralization in an open system with sulfuric acid. Mester et al. [16] compared microwave decomposition methods and a wet acid digestion in the solubilization of Cr, Ni, Cu, Pb, Cd and Zn, for their determination in fly ash. The microwave methods included different combinations of concentrated mineral acids, such as: (1) HNO 3 , (2) HNO 3 , HF and H 3 BO 3 , (3) HNO 3 , HF, H 3 BO 3 with addition of H 2 O 2 , (4) HNO 3 , HF, HF and H 3 BO 3 (5) HNO 3 , HF, HClO 4 and H 3 BO 3 . "
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    ABSTRACT: Four digestion procedures have been tested to verify their applicability to the determination of major and trace elements (Al, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sr, Ti, V, Zn) in a spent catalyst by inductively coupled plasma optical emission spectrometry (ICP-OES). Two digestion procedures have been carried out in a closed microwave system using: (1) HCl+HNO(3)+H(2)O(2); (2) HNO(3)+HF, whereas the remaining two in an open system using: (1) aqua regia+NH(4)F, HNO(3), H(2)SO(4); (2) HF+HClO(4), H(3)BO(3), HCl. Among these four procedures the microwave digestion system (1) gave the best recovery results. The quality of the analytical results has been evaluated by the analysis of the CTA-FFA-1 Fine Fly Ash Certified Reference Material. A good agreement between the measured and reference values was found for almost all elements. The precision was assessed from the replicate analyses of microwave digestion (1) system and was found to be less than 5% of the relative standard deviation (R.S.D.).
    Journal of hazardous materials 09/2008; 164(2-3):776-80. DOI:10.1016/j.jhazmat.2008.08.072 · 4.53 Impact Factor
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