Study on reduction of MoS₂ powders with activated carbon to produce Mo₂C under vacuum conditions

Abstract

A method of preparing Mo₂C via vacuum carbothermic reduction of MoS₂ in the temperature range of 1350–1550°C was proposed. The effects of MoS₂-to-C molar ratio (α, α = 1:1, 1:1.5, and 1:2.5) and reaction temperature (1350 to 1550°C) on the reaction were studied in detail. The phase transition, morphological evolution, and residual sulfur content of the products were analyzed by X-ray diffraction, field-emission scanning electron microscopy, and carbon–sulfur analysis, respectively. The results showed that the complete decomposition of MoS2 under vacuum is difficult, whereas activated carbon can react with MoS2 under vacuum to generate Mo₂C. Meanwhile, higher temperatures and the addition of more carbon accelerated the rate of carbothermic reduction reaction and further decreased the residual sulfur content. From the experimental results, the optimum molar ratio α was concluded to be 1:1.5.

Keywords

vacuum treatment / carbon thermoreduction / molybdenum minerals / molybdenum carbide / microstructure

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