Effect of calcination temperature on kaolinite for mullitisation of kaolinite and alumina mixture

Abstract

The present project work reports whether there is any effect of calcination temperature of kaolinite, on the mullitisation behavior of kaolinite and alumina mixture. Initially raw material characterization such as chemical analysis, DSC/TG analysis and XRD were carried out. Further in this experiment kaolinite was calcined at various temperatures (6000C, 10000C, 14000C) and calcined alumina powders were added in it, specimens were prepared by pressing and finally all the batches were fired at 16000C. The effect of calcination temperature was studied by performing different experiments, mainly physical properties such as apparent porosity & bulk density; mechanical properties and phase analysis by X-ray diffraction. Finally from the results it has been observed that there is always a significant impact of calcination temperature on the mullitisation behavior of kaolinite and alumina mixture. It has been found that the kaolinite that was calcined at higher temperature show some superior properties when mixed with alumina and fired, as compared to other batches. It shows higher amount of mullite content when fired along with other batches at 16000C, and also better mechanical and sintering properties. The batch that was made by mixing calcined alumina along with raw/uncalcined kaolinite show poor mechanical and sintering behavior.