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Condensation of Olefins on Clays. Gas-Solid Systems. Part II: Spectroscopic Methods

Published online by Cambridge University Press:  28 February 2024

Eduardo Choren
Affiliation:
Centro de Superficies y Catálisis, Facultad de Ingeniería, Universidad del Zulia, Apartado 15251, Maracaibo 4003A, Venezuela
Alexander Moronta
Affiliation:
Centro de Superficies y Catálisis, Facultad de Ingeniería, Universidad del Zulia, Apartado 15251, Maracaibo 4003A, Venezuela
Arnedo Arteaga
Affiliation:
Centro de Superficies y Catálisis, Facultad de Ingeniería, Universidad del Zulia, Apartado 15251, Maracaibo 4003A, Venezuela
Jorge Sánchez
Affiliation:
Centro de Superficies y Catálisis, Facultad de Ingeniería, Universidad del Zulia, Apartado 15251, Maracaibo 4003A, Venezuela

Abstract

The adsorption of olefins at 25 °C in gas- or vapor-solid systems on 4 clays dried at 120 °C was studied by infrared spectroscopy. Products of condensation have the spectra of paraffinic oligomers. Paraffins are adsorbed onto the same structural surface hydroxyls that adsorb olefins, confirming the physical unspecific character of this adsorption. These hydroxyls do not participate in the condensation reaction. The reappearance of these hydroxyl bands after evacuation suggests that product molecules are not adsorbed onto the surface but remain on it because of its low vapor pressure. The reversible adsorption sites participate in feeding the condensation sites. Double-bond isomerization of olefins was not observed, at room temperature, on clays, alumina and silicas dried at 120 °C. When the gas-phase is evacuated or swept with inert gas, reaction does not proceed with a new monomer. Paraffins are only physically adsorbed.

Type
Research Article
Copyright
Copyright © 1997, The Clay Minerals Society

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References

Breen, C., Deane, A.T. and Flynn, J.J.. 1987. Vapor-phase sorption kinetics for methanol, propan-2-ol, and 2-methyl propan-2-ol on Al3+-, Cr3+-, and Fe3+-exchanged montmorillonite. Clays Clay Miner 35: 336342.CrossRefGoogle Scholar
Choren, E., Moronta, A., Varela, G., Arteaga, A. and Sánchez, J.. 1997. Condensation of olefins on clays. Gas-solid systems Part I: Gravimetric methods. Clays Clay Miner 45: 213220.CrossRefGoogle Scholar
Fripiat, J.J. and Toussaint, F. 1963. Dehydroxylation of kaolinite II. Conductometric measurements and infrared spectroscopy. J Phys Chem 67: 3036.CrossRefGoogle Scholar
Little, L.H. and Mathieu, M.V.. 1960. Étude de la déshydratation d'un verre poreux. Actes du Deuxième Congrès International de Catalyse. Paris: Editions Technip. p 771785.Google Scholar
Lucchesi, P.J., Carter, J.L. and Yates, D.J.C.. 1962. An infrared study of the chemisorption of ethylene on aluminum oxide. J Phys Chem 66: 14511456.CrossRefGoogle Scholar
McDonald, R.. 1958. Surface functionality of amorphous silicas by infrared spectroscopy. J Phys Chem 62: 11681178.CrossRefGoogle Scholar
Mortland, M.M., Fripiat, J.J., Chaussidon, J. and Uytterhoeven, J.. 1963. Interaction between ammonia and the expanding lattices of montmorillonite and vermiculite. J Phys Chem 67: 248258.CrossRefGoogle Scholar
Peri, J.B. and Hannan, R.B.. 1960. Surface hydroxyl group on γ-alumina. J Phys Chem 64: 15261530.CrossRefGoogle Scholar
Serratosa, J. and Bradley, W.F.. 1958. Determination of the orientation of OH bond axes in layer silicates by infrared adsorption. J Phys Chem 62: 11641167.CrossRefGoogle Scholar
Tennakoon, D.T.B., Schlögl, R., Rayment, T., Klinowski, J., Jones, W. and Thomas, J.M.. 1983. The characterization of clay-organic systems. Clay Miner 18: 357371.CrossRefGoogle Scholar
van der Marel, H.V. and Beutelspacher, H.. 1976. Atlas of infrared spectroscopy of clay minerals and their admixtures. Amsterdam: Elsevier Science. p 130149.Google Scholar