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Updated: Sep 27, 2026

Determination of Inorganic Arsenic in a Wide Range of Food Matrices using Hydride Generation - Atomic Absorption Spectrometry.
Published on: September 1, 2017
Structural Characterization of Ettringite Synthesized in the Presence of Arsenate(V) and Chromate(VI) Ions
Magdalena Król1, Witold Jastrzębski1, Włodzimierz Mozgawa1
1Faculty of Materials Science and Ceramics, AGH University of Krakow, 30 Mickiewicza Av., 30-059 Kraków, Poland.
Abstract:
Ettringite (Ca6[Al(OH)6]2(SO4)3⋅26H2O) is an important hydration product involved in the immobilization of oxyanion contaminants in cementitious systems; however, the structural effects of arsenate(V) and chromate(VI) incorporation remain poorly understood. This study investigates the influence of both oxyanions on the formation and structure of ettringite-based materials using X-ray diffraction (XRD) with Rietveld refinement and Fourier-transform infrared spectroscopy (FT-IR). Ettringite remained the dominant crystalline phase in all samples, with no detectable secondary crystalline compounds. Chromate incorporation caused only minor changes in lattice parameters, whereas arsenate addition resulted in a decrease in unit cell volume, mainly due to contraction along the c axis. FT-IR analysis confirmed preservation of the ettringite framework and revealed local structural modifications, particularly for arsenate-bearing samples. The results indicate that the presence of both oxyanions is associated with structural changes in ettringite-bearing materials, with arsenate causing a stronger structural response within the investigated compositional range.
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