Síntesis y caracterización de nanoestructuras de óxidos de CoMoW parcialmente sulfuradas y su aplicación en la HDS de DBT

Synthesis and characterization of partially sulfided CoMoW oxides nanostructures and their application in the HDS of DBT

R. Huirache–Acuña¹*, M.G. Sánchez–Bautista², J. Lemus–Ruiz², C. Ornelas³, F. Paraguay–Delgado³ y E.M. Rivera–Muñoz⁴

¹ Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo Ciudad Universitaria, 58060, Morelia, Michoacán, México. *Autor para la correspondencia. E–mail: rafael_huirache@yahoo.it Tel. +52–443–322–35–00, ext. 4316, Fax +52–443–3–16–71–76.

² Instituto de Investigaciones Metalúrgicas, Universidad Michoacana de San Nicolás de Hidalgo Ciudad Universitaria, 58060, Morelia, Michoacán, México.

⁴ Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, A.P. 1–1010 Querétaro, Qro., Mexico, C.P. 76000, México.

Recibido 5 de Agosto 2009.
Aceptado 3 de Mayo 2010.

Resumen

En este trabajo, se presenta la síntesis y caracterización de nanoestructuras de óxidos de CoMoW parcialmente sulfuradas y su aplicación como catalizadores en la reacción de hidrodesulfurización (HDS) de dibenzotiofeno (DBT). Las nanoestructuras se obtuvieron a través de un método en dos etapas: hidrotérmico/reducción en fase gas. En la primera etapa (hidrotérmico) se obtiene el precursor en forma de óxidos de CoMoW. Subsecuentemente, se realizó la reducción y activación de los precursores en atmósfera de H₂S/H₂ a 500 °C (reducción en fase gas). Se analizó la morfología, estructura cristalina y propiedades texturales de los materiales mediante Microscopía Electrónica de Transmisión (MET), Difracción de Rayos X (DRX), área superficial especifica por el método BET, evaluando la actividad catalítica y la selectividad en la reacción de HDS de DBT.

Palabras clave: nanoestructuras, CoMoW, hidrodesulfurización, dibenzotiofeno.

In this paper, the synthesis and characterization of CoMoW nanostructured oxides, partially sulfided, as well as its application as catalysts in the reaction of hydrodesulfurization (HDS) of dibenzothiophene (DBT) is presented. All nanostructures were obtained by a two–step hydrothermal/gas phase reduction. Firstly, CoMoW oxides precursors were prepared using a hydrothermal method. Subsequently, all precursors were reduced and activated under H₂S/H₂ at 500°C. Nanostructures were characterized by transmission electron microscopy (TEM), X–ray powder diffraction (XRD) and the specific surface areas of the materials were measured using the BET method. The catalytic activity and selectivity measurements in the HDS of DBT reaction were also presented.

Keywords: nanostructures, CoMoW, hydrodesulfurization, dibenzothiophene.

DESCARGAR ARTÍCULO EN FORMATO PDF

Agradecimientos

Los autores agradecen a W. Antúnez, E. Torres y Dra. Beatriz Milán Malo por la asistencia técnica en Microscopía Electrónica de Trasmisión y Difracción de rayos X. Este trabajo fue apoyado por CONACYT, PAPIIT–DGAPA–UNAM IN113806.

Referencias

Albiter, M. A., Huirache–Acuña, R., Paraguay–Delgado, F., Rico, J. L., Alonso–Núñez, G. (2006). Synthesis of MoS₂ nanorods and their catalytic test in the HDS of Dibenzothiophene. Nanotechnology 17 (14), 3473–3481.         [ Links ]

Bollinger, M.V., Lauritsen, J.V., Jacobsen, K.W., Norskov, J.K., Helveg, S., Besenbacher, F. (2001). One–dimensional metallic edge states in MoS₂. Physics Review Letters 87, 196803.         [ Links ]

Breysse, M., Geantet, Ch., Afanasiev, P., Blanchard, J., Vrinat, M. (2008). Recent studies on the preparation, activation and design of active phases and supports of hydrotreating catalysts. Catalysis Today 130, 3–13.         [ Links ]

Camacho–Bragado, G. A., Elechiguerra, J.L., Olivas, A., Fuentes, S., Galván, D., José Yacamán, M. (2005). Structure and catalytic properties of nanostructured molybdenum sulfides. Journal of Catalysis 234, 182–190.         [ Links ]

Changsheng, Li, Junmao, Li, Kehong, Yan, Yanqing, Liu, Wanzhang, Liu, Xinya, Song, Zhou, Qian (2006). The Synthesis and Nanotribology Study of MS₂ Nanotube, Nano/Micro Engineered and Molecular Systems, NEMS '06. 1^st IEEE International Conference pp. 1142–1146.         [ Links ]

Chianelli, R. R., Prestidge, E. B., Pecoraro, T. A., Deneufville, J. P. (1979). Molybdenum Disulfide in the Poorly Crystalline "Rag" Structure. Science 203, 1105–1107.         [ Links ]

Chianelli, R.R., Berhault, G., Torres, B. (2009). Unsupported transition metal sulfide catalysts: 100 years of science and application. Catalysis Today 147, 275–286.         [ Links ]

Galatsis, K., Li, Y.X., Wlodarski, W., Kalantar–zadeh, K. (2001). Sol–gel prepared MoO₃–WO₃ thin– films for O₂ gas sensing. Sens Actuators B 77, 478–83.         [ Links ]

Harris, S. y Chianelli, R. R., (1986). Catalysis by Transition Metal Sulfides: A Theoretical and Experimental Study of the Relation between the Synergic Systems and the Binary Transition Metal Sulfides. Journal of Catalysis 98, 17–31.         [ Links ]

Huirache–Acuña, R., Albiter, M. A., Espino, J., Ornelas, C., Alonso–Núñez, G., Paraguay–Delgado, F., Rico, J. L., Martínez–Sánchez, R. (2006). Synthesis of Ni–Mo–W sulfide catalysts by ex–situ decomposition of trimetallic precursors. Applied Catalysis A: General 304, 124–130.         [ Links ]

Huirache–Acuña, R., Albiter, M. A., Ornelas, C., Paraguay–Delgado, F., Martínez–Sánchez, R., Alonso–Núñez, G. (2006). Ni(Co)–Mo–W Sulphide unsupported HDS catalysts by ex–situ decomposition of alkylthiomolybdotungstates. Applied Catalysis A: General 308, 134–142.         [ Links ]

Huirache–Acuña, R., Paraguay–Delgado, F., Albiter, M.A., Alvarez–Contreras, L., Rivera–Muñoz, E.M. y Alonso–Núñez, G. (2009). Synthesis and Characterization of WO₃ and WS₂ hexagonal phase nanostructures and catalytic test in sulfur remotion. Journal of Materials Science 44, 4360–4369.         [ Links ]

Huirache–Acuña, R., Pawelec, B., Rivera–Muñoz, E., Nava, R., Espino, J., Fierro, J.L.G. (2009). Comparison of the morphology and HDS activity of ternary Co–MoW supported on P–modified SBA–15 and SBA–16 substrates. Applied Catalysis B: Environmental, 92, 168–184.         [ Links ]

Kabe, T., Qian, W., Ishihara, A. (1994). Study of Hydrodesulfurization of Dibenzothiophene on Ni–Mo/Al₂O₃, Mo/Al₂O₃, and Ni/Al₂O₃ Catalysts by the Use of Radioisotope ³⁵S Tracer. Journal of Catalysis 149, 171–180.         [ Links ]

Li, Y.B., Bando, Y., Goldberg, D. (2003). MoS₂ nanoflowers and their field–emission properties. Applied Physics Letters 82, 1962–1964.         [ Links ]

Liang, K. S., Chianelli, R. R., Chien, F. Z., y Moss S. C. (1986). Structure of poorly crystalline MoS₂–A modeling study. Jounal of Non–Crystalline Solids 79, 251–273.         [ Links ]

Nava, H., Pedraza, F. y Alonso G. (2005). Nickel–Molybdenum–Tungsten sulfide catalysts prepared by in situ activation of tri–metallic (Ni–Mo–W) alkylthiomolybdotungstates. Catalysis Letters 99, 65–71.         [ Links ]

Nava, R., Morales, J., Alonso, G., Ornelas, C., Pawelec B. and. Fierro, J.L.G. (2007). CoMo/Ti–SBA–15 catalysts for dibenzothiophene desulfurization. Applied Catalysis A: General 321, 58–70.         [ Links ]

Olivas, A., Galván, D.H., Alonso, G., Fuentes, S. (2009). Trimetallic NiMoW unsupported catalysts for HDS. Applied Catalysis A: General 352, 10–16.         [ Links ]

Soled, S.L., Miseo, S., Krycak, R., Vroman, H., Ho, T. C., Riley, K. Nickel molybodtungstate hydrotreating catalysts. United States Patent 6,299,760 October 9, 2001.         [ Links ]

Tenne, R. (2002). Fullerene–like materials and nanotubes from inorganic compounds with a layered (2–D) structure. Colloids and Surface A 208, 83–92.         [ Links ]

Therese, H. A., Li, J., Kolb, U., Tremel, W. (2005). Facile large scale synthesis of WS2 nanotubes from WO₃ nanorods prepared by a hydrothermal route. Solid State Sciences 7, 67–72.         [ Links ]

Whitehurst D.D., Isoda T. and Mochida I. (1998). Present state of the art and future challenges in the hydrodesulfurization of polyaromatic sulfur compounds. Advances in Catalysis 42, 345–471.         [ Links ]