Optimisation of processing parameters for making pyrophyllite based ceramic tiles using di-sodium hydrogen phosphate binder.

The processing parameters for making tiles using pyrophyllite with di-sodium hydrogen phosphate binder have been optimised. Infrared studies on sintered tiles prepared under optimised conditions indicate the presence of Si–O linkages and the formation of AlPO4. Using X-ray powder diffraction the various phases formed during sintering were identified as the tridymite form of aluminium phosphate (T-AlPO4), dehydroxylated pyrophyllite, and sodium silicate. Thermal changes taking place during sintering were studied using thermal analysis. Scanning electron micrographs revealed the presence of acicular T-AlPO4 crystals and dehydroxylated pyrophyllite with platelet morphology