Small Angle Neutron Scattering Study of a Gehlenite-Based Ceramic Fabricated from Industrial Waste

Abstract

This paper presents a small angle neutron scattering (SANS) study of a novel porous gehlenite-based ceramic, synthesised from a homogeneous powder mixture of soda-lime-silicate (SLS) glass, α-alumina, calcite and calcium fluoride via solid-state sintering at 1200 °C. The products of sintering at single temperatures from 600 to 1200 °C are examined by X-ray diffraction (XRD). Sintering of the mixture below 1200 °C forms two intermediate phases (Na2CaSi3O8 and Ca4Si2O7F2). Nepheline and α-alumina are minor phases in the gehlenite-based ceramic fabricated through sintering at 1200 °C. The microstructure of the gehlenite-based ceramic is investigated using field-emission scanning electron microscopy (FESEM) and SANS at the Australian Centre for Neutron Scattering. This study also evaluated the specific surface area of the gehlenite-based ceramic (~3.0 m2 cm–3) from quantitative analysis of SANS data.

Multifunctional Carbon-Based Hybrid Foams for Shape-Stabilization of Phase Change Materials, Thermal Energy Storage, and Electromagnetic Interference Shielding Functions

“…Specifically, the absorption band at 560 cm −1 can be assigned to Ti-O stretching and the band at 435 cm −1 to the Ti-O-Ti bending vibrations, respectively [61,62]. Furthermore, absorption bands centered at 1017 cm −1 , 975 cm −1 could be assigned to the asymmetric stretching vibrations of Si-O-Si and Si-O-Al groups of gehlenite (Ca 2 Al[AlSiO 7 ]) [63]. The absorption peaks observed in the frequency range 920-800 cm −1 and below 500 cm −1 can be attributed to AlO 4 tetrahedral and AlO 6 octahedral groups of tricalcium aluminate (3CaO Al 2 O 3 or C 3 A) [64,65].…”