بررسی سینتیک احیای کربوترمی مولیبدنیت در حضور کربنات سدیم

in this research, the kinetics of carbothermic reduction of molybdenite in the presence of sodium carbonate was studied. For this purpose, mixed powder of molybdenite, graphite, and sodium carbonate with 1:4:2 mole ratio was investigated using simultaneous thermal analysis (STA) at the heating rates of 10, 15 and 20 0C /min. The results of thermal analysis were evaluated through Friedman, Kissinger, Ozawa and Coats-Redfern methods. The activation energy of reduction reaction was determined 220 kj/mole, and it was found that the reaction was chemically controlled. To study the reaction mechanism, the mixed powder was heated to 400, 800 and 1100 0C in argon atmosphere at the heating rate of 10 0C/min. X- Ray diffraction of the reaction products and thermodynamic analysis at these temperatures indicated that carbothermic reduction of molybdenite in the presence of sodium carbonate would advance through the formation of intermediate phases, Na2MoO4 and MoO2