N-HEPTANE ISOMERIZATION OVER Pt/TUNGSTATED ZIRCONIA CATALYSTS

  • J.A. Montoya de la Fuente
  • M.L. Hernández-Pichardo
  • P. del Angel V
Keywords: n-heptane isomerization, tungstated zirconia, cracking

Abstract

Platinum supported on tungstated zirconia catalysts were synthesized and evaluated in the n-heptane isomerization reaction. The catalysts were synthesized by surfactant-assisted coprecipitation with recirculation and without recirculation. The synthesis of the catalysts and the characterization results by High resolution transmission electron microscopy (HRTEM), X-ray diffraction and Laser Raman spectroscopy are presented, as well as the results for the catalytic evaluation at different reaction conditions. This work suggests that cracking products were formed mainly of bi-branched isomers of n-heptane and they were favored at high reaction temperatures. Finally, it was observed that use of the catalyst synthesized by reflux decreased the cracking activity, improving the selectivity to higher octane isomers.

References

Barton, D. G., Shtein, M., Wilson, R. D., Soled, S. L. e Iglesia, E. (1999). Structure and electronic properties of solid acids based on tungsten oxide nanostructures. The Journal of Physical Chemistry B 103, 630-640.

Cortez-Lajas, L. A., Hernández-Enríquez, J. M., Castillo-Mares, A., Rivera-Armenta, J. L., Sandoval-Robles, G., García-Serrano, L. A. y García-Alamilla, R. (2006). Isomerización de n-pentano mediante óxidos de circonio dopados con ión borato. Revista Mexicana de Ingeniería Química 5, 321-327.

García-Alamilla, R., Ramos-Galván, C. E., Sandoval-Robles, G., Melo-Banda, J. A. y García-Serrano, L.A. (2005). Isomerización de n-pentano sobre Pt/H-mordenita y Pt- Re/H-mordenita-Al2O3. Revista Mexicana de Ingeniería Química 4, 253-260.

Hernández, M. L., Montoya, J. A., Hernández, I., Viniegra, M., Llanos, M. E., Garibay, V. y Del Angel P. (2006). Effect of the surfactant on the nanostructure of mesoporous Pt/Mn/WOx/ZrO2 catalysts and their catalytic activity in the hydroisomerization of n-hexane. Microporous and Mesoporous Materials 89,186-195.

Hernández-Pichardo, M. L., Montoya J. A. y Navarrete, J. (2008). A comparative study of theWOx dispersion on Mn-promoted tungstated zirconia catalysts prepared by conventional and high-throughput experimentation. Applied Catalysis A 345, 233-240.

Hernández-Pichardo, M.L., Montoya de la Fuente, J.A., del Angel, P., Vargas, A., Navarrete, J., Hernández, I., Lartundo, L. y González- Brambila, M. (2012). High-throughput study of the iron promotional effect over Pt/WOx- ZrO2 catalysts on the skeletal isomerization of n-hexane. Applied Catalysis A, 69-78.

Khurshid M., Al-Daous M. A., Hattori H. y Al- Khattaf S. (2009). Effects of hydrogen on heptane isomerization over zirconium oxide modified with tungsten oxide and platinum. Applied Catalysis A 362, 75-81.

Khurshid, M. y Al-Khattaf, S. S. (2009). n-Heptane isomerization over Pt/WO3-ZrO2: A kinetic study. Applied Catalysis A 368, 56-64.

Kimura, T. (2003). Development of Pt/SO2- 4 /ZrO2 catalysts for isomerization of light naphta. Catalysis Today 81, 57-63.

Rodríguez, L. M. y Méndez, S. (2000). ¿Reformar o isomerizar la fracción C5-C6 de la nafta ligera? Revista del IMIQ 7-8, 15-22.

Ross-Medgaarden, E. I. y Wachs, I. E. (2007). Structural determination of bulk and surface tungsten oxides with UV-vis diffuse reflectance spectroscopy and Raman spectroscopy. Journal of Physical Chemistry C 111, 15089-15099.

Valigi, M., Gazzoli, D., Cimino, A. y Proverbio, E. (1999). ionic size and metal uptake of chromium (VI), molybdenum(VI), and tungsten (VI) species on ZrO2-based catalyst precursors. Journal of Physical Chemistry B 103, 11318-11326.

Vaudagna, S.R., Canavese, S.A., Comelli, R.A. y Fígoli, N.S. (1998). Platinum supported WO3-ZrO2: effect of calcination temperature and tungsten loading. Applied Catalysis A 168, 93-111.

Vu, T. N., van Gestel, J., Gilson, J. P., Collet, C., Dath, J.P. y Duchet, J. C. (2005). Platinum tungstated zirconia isomerization catalysts Part II. Effect of platinum and tungsten loading on the mechanism of isomerization of n-hexane: a kinetic study. Journal of Catalysis 231, 468- 479.

Wong, S.T., Li, T., Cheng, S., Lee J.F. y Mou, Ch.Y. (2005). Platinum- and irondoubly promoted tungstated zirconia catalyst for n-butane isomerization reaction. Applied Catalysis A 296, 90-99.
Published
2020-04-25
How to Cite
Montoya de la Fuente, J., Hernández-Pichardo, M., & del Angel V, P. (2020). N-HEPTANE ISOMERIZATION OVER Pt/TUNGSTATED ZIRCONIA CATALYSTS. Revista Mexicana De Ingeniería Química, 11(3), 439-445. Retrieved from http://www.rmiq.org/ojs311/index.php/rmiq/article/view/1620
Section
Catalysis, kinetics and reactors