Influence of dopant metal ions on the formation of cordierite using combined SAXS/WAXS and EXAFS/WAXS techniques

Time-resolved combined scattering and spectroscopic techniques were used to understand in detail the formation of cordierite ceramic from two sources, (a) zeolite B and (b) cordierite glass systems. Time-resolved in situ combined EXAFS/XRD (at the Zn K-edge) investigation of the zinc oxide mixed zeolite B reveal that a series of transformations occur before the formation of cordierite ceramic. In particular the study revealed that addition of small amounts of zinc oxide promote the transformation of cordierite, through the formation of ZnAl2O4, at lower temperatures compared to the system without zinc oxide. Using in situ time-resolved SAXS/WAXS technique chromium doped in the cordierite glass system was investigated which revealed that, in addition to the formation of phase pure cordierite phase some amount of MgCr2O4 spinel phase are also produced.