Synthesis of Ni-spinel/aluminosilicate composite ceramics mixed at nanoscale level by using zeolite precursors

Abstract

Thermally induced phase transformation of Ni-exchanged LTA, FAU, GIS and MOR zeolites were studied in the temperature range from room to 1500 °C. All investigated zeolite frameworks collapsed into amorphous intermediate products after heating between 800-900 °C. Prolonged heating of the intermediate products obtained from the Ni-exchanged zeolites over 900 °C, induces recrystallization of Ni-spinel phase (cubic-NiAl2O4) in all cases whereas silicate part recrystallizes into Ni-stuffed derivative phase of cristobalite (at Ni-GIS and Ni-MOR zeolite) or stay amorphous. Phase composition of ceramic products were studied by XRPD, SEM and IR techniques.