A Sulfur Emission-Free Route for the Synthesis of Mo and Mo2C via Carbothermal Reduction of MoS2

• Published in: Metallurgical and materials transactions. B, Process metallurgy and materials processing science Process metallurgy and materials processing science, 2022-02, Vol.53 (1), p.96-106
• Main Authors: Chang, He-Qiang, Zhang, Guo-Hua, Chou, Kuo-Chih
• Format: Article
• Language: English
• Subjects: Additives; Carbon; Carbon black; Characterization and Evaluation of Materials; Chemistry and Materials Science; Desulfurizing; Materials Science; Metallic Materials; Molybdenum; Molybdenum disulfide; Nanotechnology; Original Research Article; Reduction; Structural Materials; Sulfur; Surfaces and Interfaces; Synthesis; Thin Films
• ISSN: 1073-5615; 1543-1916
• DOI: 10.1007/s11663-021-02345-w

In this work, the sulfur-free emission route for the synthesis of Mo and Mo 2 C via carbothermal reduction of MoS 2 was proposed. The internal MoS 2 -C mixture is wrapped by an external desulfurization layer composed of CaO and C. In the internal layer, MoS 2 reacted with carbon black and generated Mo, Mo 2 C (or their mixture), as well as S 2 , CS 2 and CS gas. Both experiments and thermodynamic calculations show that the main gaseous product should be CS 2 . The sulfur-containing gas produced can be completely captured by the desulfurization layer in the form of CaS. This strategy can avoid the emission of S-containing gas compared with the traditional route. In addition, after removing the unreacted desulfurizer and gently breaking the desulfurization product layer, the molybdenum-containing product can be collected. For the raw material with a MoS 2 :C molar ratio of 1:1, after reacting at 1600 °C for 4 hours, Mo with carbon and sulfur contents of 0.053 and 0.050 pct is acquired. In addition, Mo 2 C-dominant product can be obtained after reacting at 1600 °C for 4 hours at a MoS 2 :C molar ratio of 1:1.52, with the carbon and sulfur contents of 5.878 and 0.049 pct. The above shows that this strategy has the advantages of high-efficiency desulfurization and simple separation of desulfurization product, which is an environment-friendly method for the production of molybdenum additives.