• R. Zanella
  • R. Cuevas
  • J. Ramírez
  • L. Cedeño
Keywords: Al2O3, CoMo, HDS, mixed oxides, Mo, NiMo, NO adsorption, TPS, TPR-S, TiO2


The effect of the support composition on the surface structure of Mo, CoMo and NiMo catalysts on TiO2-Al2O3 mixed oxides was characterized in the sulfided state by FT-IR spectroscopy of adsorbed NO, TPS and TPR-S techniques, before and after HDS thiophene reaction. The NO adsorption studies on the sulfided unpromoted Mo catalysts showed that the variation of total NO adsorbed and the catalytic activity follow a similar trend with the Ti content. However, in the case of the promoted catalysts the results indicate the presence of less sulfided Co and Ni species at intermediate Ti contents. Activity variations with Ti content were associated to changes in sulfidation evidenced by the NO frequency band shifts. Moreover, the changes induced by the presence of titania, on the molybdenum sulfided phases after the reaction test, can be assessed in part by the TPR-S technique. A quantitative analysis of the UV signal in the region 25-300 °C of the TPR-S patterns show that the H2S produced in this region, which is related to the number of sulfur vacancies created, coincide with the HDS activity trend


Cedeño, L., Ordóñez, L., Cuevas, R. y Ramírez, J. (1998). Estudio por TPS y TPR-S del proceso de activación de catalizadores de Mo/Al2O3 para hidrotratamiento. Actas del XVI Simposium Iberoamericano de Catálisis 3, 2033-2038.

Cedeño, L., Ordóñez, L., Cuevas, R. y Ramírez, J. (1998). Estudio de la activación de catalizadores para HDT.II Catalizadores Mo/TiO2 y Ni-Mo/TiO2, Avances en Ingeniería Química 8(3), 98-101.

Luck, F. (1991). A review of support effects on the activity and selectivity of hydrotreating catalysts. Bulletin Societe Chimique Belgique 11-12, 781-800.

Okamoto, Y., Maezawa, A. e Imanaka, T. (1989). Active sites of molybdenum sulfide catalysts supported on Al2O3 and TiO2 for hydrodesulfurization and hydrogenation, Journal of Catalysis 120, 29-45.

Olguin, E., Vrinat, M., Cedeño, L., Ramírez, J., Borque, M. y López-Agudo A. (1997). The use of TiO2-Al2O3 binary oxides as supports for Mo-based catalysts in hydrodesulfurization of tiophene and dibenzothiophene. Applied Catalysis 165, 1-13.

Portela, L., Grange, P. and Delmon, B. (1995). The adsorption of nitric oxides on supported Co-Mo hydrodesulfurization catalysts: A review, Catalysis Review Science Engineering 37, 699-731.

Ramírez, J., Ruiz, L., Cedeño, L., Harle, V., Vrinat, M. y Breysse, M. (1993). Titania-alumina mixed oxides as supports for molybdenum hydrotreating catalysts. Applied Catalysis 93, 163-180.

Ramírez, J., Cedeño, L. y Busca, G. (1999). The role of titania support in Mo-Based Hydrodesulfurization catalysts. Journal of Catalysis 184, 59-67.

Scheffer, B., Mangnus, P. J. y Moulijn, J. A. (1990). A temperature programmed reduction study of sulfided Co-Mo/Al2O3 hydrodesulfurization catalysts. Journal of Catalysis 121, 31-46.

Topsoe, N. y Topsoe, H. (1982). Adsorption studies on hydrodesulfurization catalysts. Journal of Catalysis 75, 354-374.

Topsoe, N. y Topsoe, H. (1983). Characterization of the structures and active sites in sulfided Co-Mo/Al2O3 and Ni-Mo/Al2O3 catalysts by NO chemisorption. Journal of Catalysis 84, 386-401.

Zhaobin, W., Qin, X., Xiexian, G., Grange, P. y Delmon, B. (1991). Titania-modified hydrodesulfurization catalysts. II. Dispersion state and catalytic activity of molybdena supported on titania-alumina carrier. Applied Catalysis 75, 179-191.
How to Cite
Zanella, R., Cuevas, R., Ramírez, J., & Cedeño, L. (2020). CHARACTERIZATION OF Mo, NiMo AND CoMo CATALYSTS IN THEIR SULFURED STATE. Revista Mexicana De Ingeniería Química, 1(1), 13-21. Retrieved from

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