Please use this identifier to cite or link to this item:

Title: Adsorption of n-Pentane and iso-Octane for the Evaluation of the Porosity of Dealuminated BEA Zeolites
Authors: Ribeiro Carrott, M. M. L.
Russo, P. A.
Carvalhal, C.
Carrott, P. J. M.
Marques, J. P.
Lopes, J. M.
Gener, I.
Guisnet, M.
Ramôa Ribeiro, F.
Editors: Stocker, M.
Keywords: Zeolite BEA
Issue Date: 2005
Publisher: Elsevier
Citation: Microporous & Mesoporous Materials, 81 (2005) 259-267.
Abstract: Adsorption of n-pentane and 2,2,4-trimethylpentane at 298 K was carried out in order to characterize the porosity of a series of HBEA dealuminated zeolites. The HBEA samples were prepared from a calcined parent sample by steaming, by treatment with hydrochloric acid and by treatment with ammonium hexafluorosilicate (HFS) solutions. The comparison of the adsorption results with those previously obtained by nitrogen adsorption, show that the use of this latter adsorptive alone is insufficient for evaluating the changes provoked by dealumination. The narrow mesopores which were found in the parent sample show distinct behaviour with respect to each of the organic adsorptives. Treatment with HFS solutions and steaming causes the most significant changes in the microporosity, decreasing the micropore volumes of the samples. The former also causes a substantial loss of external area. Treatment with HCl solutions primarily removes extra-framework aluminium species formed during calcination; while this treatment has no significant effect on the microporosity, it causes an increase in the external areas of the samples. The removal of extra-framework aluminium species from the mesopores of the calcined sample contributes towards this increase. On the other hand, these mesopores are blocked during steaming and treatment with HFS solutions.
Type: article
Appears in Collections:QUI - Publicações - Artigos em Revistas Internacionais Com Arbitragem Científica
CQE - Publicações - Artigos em Revistas Internacionais Com Arbitragem Científica

Files in This Item:

File Description SizeFormat
BetaMMM81(2005)259-267.pdf278.09 kBAdobe PDFView/OpenRestrict Access. You can Request a copy!
FacebookTwitterDeliciousLinkedInDiggGoogle BookmarksMySpaceOrkut
Formato BibTex mendeley Endnote Logotipo do DeGóis 

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.


Dspace Dspace
DSpace Software, version 1.6.2 Copyright © 2002-2008 MIT and Hewlett-Packard - Feedback
UEvora B-On Curriculum DeGois