Heavy metal exchanged zeolites as precursors for high temperature stable phases

Dense heavy metal containing phases were synthesized by the calcination of ion exchanged zeolites. The phases formed and their properties were dependent on various parameters such as ion exchange conditions, calcination conditions and composition of the zeolites. The type of exchanged cation determined the structures that were formed during the calcination. Generally, thermodynamically stable phases were formed at high temperature and sufficiently long calcination but by kinetic control metastable intermediates could be obtained as well. The control of these parameters enabled the synthesis of high temperature stable materials with well defined properties, which can be used as refractive materials and for catalysis or sensor technology