| Abstract
| - Information about Cd distribution inside single municipalsolid waste and biomass fly ash particles is fundamentalsince it affects its leachability. The internal 2D distributions of the main and trace elements in such highlyinhomogeneous matrixes were successfully determinedby means of the combined synchrotron radiation inducedmicro X-ray fluorescence (μ-SRXRF) and tomography (μ-SRXRFT) techniques. Scanning μ-SRXRF measurementsshow Cd elemental distribution within single fly ashparticles to be inhomogeneous, but no information canbe obtained about its internal distribution. During μ-SRXRFT analysis, single fly ash particles are successivelymeasured by a rotational−translational scan in a VH = 2× 5 μm2 microbeam. The 2D internal elemental distribution images, obtained by the modified simultaneousalgebraic reconstruction technique algorithm, provide thesize and the location of Cd-containing areas together withthe location of other measurable elements. Results showedCd concentration to be higher in the core of the fly ashparticles analyzed rather than on the surface of theparticles. Moreover, in both ashes, Ca-containing matrixesare found to be the main Cd-bearing phases. A possiblemechanism for Cd adsorption on the fly ash particles isproposed based on the obtained results.
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