- Title
- Fischer-Tropsch synthesis: effect of promoter type on alumina-supported Mo carbide catalysts
- Creator
- Vo, Dai-Viet N.; Nguyen, Tuan-Huy; Kennedy, Eric M.; Dlugogorski, Bogdan Z.; Adesina, Adesoji A.
- Relation
- Catalysis Today Vol. 175, Issue 1, p. 450-459
- Publisher Link
- http://dx.doi.org/10.1016/j.cattod.2011.04.045
- Publisher
- Elsevier BV
- Resource Type
- journal article
- Date
- 2011
- Description
- Molybdenum carbide catalysts promoted with K, Na, Co, and Ce have been synthesized by temperature-programmed carburization using a mixture of H₂/C₃H₈ and evaluated for the Fischer–Tropsch synthesis. Both α- and β-Mo carbide catalysts were produced during carburization via the formation of oxycarbide intermediate phase. The two-stage Mo carbide synthesis appeared to be characterized by a compensation effect and isokinetic relationship for both promoted and undoped catalysts suggesting that the solid state transformation mechanism was similar across the promoters. The catalysts possessed relatively high BET area (177–210 m² gcat⁻¹) with finely dispersed Mo carbide particles (ca. 10 nm) on the alumina support. The presence of weak and strong acid–base sites was also confirmed by NH₃ and CO₂-TPD runs. CO hydrogenation rate increased with H₂ composition reaching optimal activity at ᵧH₂ between 0.67 and 0.75. FT activity improved with promoter addition in the order; K–MoC₁₋ᵪ/Al₂O₃> Na–MoC₁₋ᵪ/Al₂O₃> Ce–MoC₁₋ᵪ/Al₂O₃> Co–MoC₁₋ᵪ/Al₂O₃> MoC₁₋ᵪ/Al₂O₃ while chain growth probability varied with feed composition and was enhanced by all promoters. The reaction rate data were adequately described by an Eley–Rideal model.
- Subject
- Fischer-Tropsch synthesis; promoted-molybdenum carbide; temperature-programmed carburization
- Identifier
- http://hdl.handle.net/1959.13/1056443
- Identifier
- uon:16044
- Identifier
- ISSN:0920-5861
- Language
- eng
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