Solid Phase Synthetic Reaction of Sodium Pyroxene for Na2CO3-Fe(OH)3-H2SiO3 System

In order to explore synthetic method of pure sodium pyroxene, the pure chemical reagents of Na2CO3, Fe(OH)3 and H2SiO3 were used as raw materials, and the possible solid phase reactions for Na2CO3-Fe(OH)3-H2SiO3 system in heating process had been studied by means of differential thermal analysis (DTA) and X-ray diffraction (XRD). The influencing factors of sodium pyroxene (NaFeSi2 O6) synthetic reaction, such as sintering temperature and holding time, had also been studied. The results show that sodium pyroxene can be largely synthesized at 737 °C; it is helpful for synthesis of sodium pyroxene to increase sintering temperature appropriately, and the best temperature should be controlled at 900 °C or so, because it will melt and decompose at temperatures higher than 900 °C. In those influencing factors of sodium pyroxene synthesis the most important is temperature. The results will be helpful for providing pure NaFeSi2 O6 for further research on the formation of SFCA for NaFeSi2 O6-KAlSi2 O3-CaO-Fe2 O3-CaF2 system in the sintering process of Bayan-obo iron ore.