Abstract
The thermal reactions of mechanically activated coal and natural wolframite mixtures have been studied using DTA–TG. The reaction mixture, prepared on the basis of a thermodynamic simulation, was milled in a planetary ball mill for either 2 or 4 h. Unmilled and milled mixtures were subjected to differential thermal analysis under nitrogen and argon atmospheres with the crystalline phase composition determined with XRD. The main differences between nitrogen and argon atmospheres were observed in the raw samples. Milled samples produced primarily an iron tungsten phase, Fe7W6. Under the nitrogen atmosphere, both samples showed a greater extent of reduction than under argon.
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Acknowledgements
Authors wish to thank Dr. Nicholas Welham for his critical suggestions and thermodynamic simulation. This work based on project “Research on preparation of nano sized tungsten carbide from natural minerals with assistance of mechanical activation” which obtained partial support from the Asia Research Center, Mongolia, and Korea Foundation for Advanced Studies, Korea.
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Temuujin, J., Telmenbayar, L. Carbothermic reactions of mechanically milled coal and wolframite mixtures under Ar and N2 atmospheres. J Therm Anal Calorim 121, 597–601 (2015). https://doi.org/10.1007/s10973-015-4601-5
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DOI: https://doi.org/10.1007/s10973-015-4601-5