Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.560893
Title: 1-butene isomerisation over amorphous silica-alumina
Author: Agulló Pastor, Javier
Awarding Body: University of Aberdeen
Current Institution: University of Aberdeen
Date of Award: 2012
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Abstract:
The dehydroxylation process of pseudo-boehmite to yield acidic amorphous silica-alumina has been investigated by increasing the temperature of the sample and recording DRIFTS spectra of its surface and monitoring the water released with an on-line mass spectrometer. The Brønsted and Lewis acid sites density of amorphous silica-alumina has been determined by IR-spectrometry of adsorbed pyridine and using molar extinction coefficients specific for this system for silica-alumina samples calcined at different temperatures. The deactivation profiles of 1-butene isomerisation (double-bond migration) over amorphous silica-alumina samples calcined at different temperatures have been acquired by using a fixed bed laboratory reactor coupled to a gas chromatograph with an automated sampling valve. The initial activities of amorphous silica-alumina calcined at different temperatures correlated with the Brønsted acid site density of the samples. The deactivation profiles are consistent with a reversible rehydration deactivation mechanism involving both Brønsted and Lewis acid sites and simultaneous to an irreversible deactivation mechanism involving Lewis acid sites. Brønsted acid sites are considered to be the active sites of the reaction, whereas part of the Lewis acid sites is converted into Brønsted acid sites by rehydration.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.560893  DOI: Not available
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