XRD diffraction data and Rietveld refinement of Na₈[Si₆Al₆O₂₄]Cl₂

Abstract

A natural sodalite from the geological site Alkaline Complex of Floresta Azul, Bahia, Brazil, has been characterized by electron microprobe, infrared spectroscopy, and powder high-resolution X-ray diffraction techniques. The mineral is an aluminosilicate framework, formed by cages called sodalite unity. Although the sample is natural, the chemical analysis reveals that it is indeed the end member sodalite sensu strictu, Na 8 ͓Si 6 Al 6 O 24 ͔Cl 2 . Infrared spectroscopy shows Si, Al tetrahedral-oxygen stretching nonsymmetric mode, stretching symmetric mode, and bending modes. Indexing of the experimental X-ray diffraction pattern led to cubic space group P-43n, and unit-cell parameters: a = 8.8767͑7͒ Å, D x = 2.301 g cm −3 , and V = 699.46͑1͒ Å 3 . X-ray diffraction data are reported. Rietveld refinement was also performed, and the confidence factors are Rp= 0.079, Rwp= 0.118, and 2 = 2.19. The structure of the minerals of sodalite group holds four different tetrahedra: AlO 4 , ClNa 4 , Na͑ClO 3 ͒, and SiO 4 , with Al, Cl, Na, and Si located at the center of each tetrahedron.

Glass binder development for a glass-bonded sodalite ceramic waste form

“…values revealed some closed porosity because all three values were lower than the density of the P57 glass at 2.2690×10 3 kg m -3 and the chlorosodalite phase, which literature shows ranges from 2.27×10 3 kg m -3 [52] (ICSD#98812) to 2.30×10 3 kg m -3 [53] (ICSD#166827). For the other samples, the ρ b,p values were close to expected values with slightly higher densities than sodalite due to the increased density of the added glass binders ( Table 6).…”