Belite cement clinker from coal fly ash of high Ca content.: Optimization of synthesis parameters

The optimization of parameters of synthesis of belite cement clinker from coal fly ash of high Ca content is presented in this paper. The synthesis process is based on the hydrothermal-calcination-route of the fly ash without extra additions. The hydrothermal treatment was carried out in demineralized water and a 1 M NaOH solution for 4 h at the temperatures of 100 degreesC, 150 degreesC, and 200 degreesC. The precursors obtained during the hydrothermal treatment were heated at temperatures of 700 degreesC, 800 degreesC, 900 degreesC, and 1000 degreesC. The changes of fly ash composition after the different treatments were characterized by X-ray diffraction (XRD), FT infrared (FTIR) spectroscopy, surface area (BET-N-2), and thermal analyses. From the results obtained we concluded that the optimum temperature of the hydrothermal treatment was 200 degreesC, and the optimum temperature for obtaining the belite cement clinker was 800 degreesC.