PNNL

Abstract

X-ray powder diffraction data for a new zeolite, Na8(AlSiO4)6(ReO4)2, are reported. Rietveld refinement shows this compound adopts the primitive cubic structure of sodalite (Space Group , #218) with a = 9.1528 (1) Å. The calculated value of the reference intensity ratio (RIR, or I/Ic) is 7.54. The experimental density (Dm) is 2.98 ± 0.10 g/cm3, in agreement with the calculated density (Dx) of 3.029 g/cm3. Chemical analysis of Na8(AlSiO4)6(ReO4)2 gives its composition as 11.7 ± 1.6 wt % Na; 10.7 ± 0.2 wt % Al; 11.6 ± 0.9 wt % Si; 30.6 ± 1.2 wt % Re, which compares favorably with the theoretical composition of 13.2 wt % Na, 11.6 wt% Al, 12.1 wt% Si; 26.6 wt % Re. In addition, scanning electron microscopy reveals a doubly terminated trapezohedral crystal morphology for Na8(AlSiO4)6(ReO4)2, which is typical of sodalite.