Please use this identifier to cite or link to this item:
Author(s): Alexandre Filipe Porfírio Ferreira
Title: Can alkane isomers be separated? Adsorption equilibrium and kinetic data for hexane isomers and their binary mixtures on MFI
Issue Date: 2007
Abstract: In this study we present a global overview of the adsorption behavior of hexane isomers on MFI. With an experimental approach that couples a manometric technique with Near Infrared (NIR) spectroscopy, which has been recentlydeveloped, we did address adsorption kinetic propertiesof n-hexane, 2-methylpentane, 2,2-dimethylbutane and2,3-dimethylbutane, and their binary mixtures. The adsorption equilibrium properties of the binary mixtures were also assessed using the same technique. Whereas the adsorption isotherms and heats of adsorption for single components have been studied by a manometric technique coupled with a micro calorimeter. The differential heats of adsorption of n-hexane increase slightly with loading, on the other hand the heat of adsorption of branched hexanes exhibits a decrease with loading. The diffusion rates on MFI of nhexane, 2-methylpentane and 2,3-dimethylbutane are in the same order of magnitude. However, the diffusion rate of 2,2- dimethylbutane is two orders of magnitude lower than rates of the other isomers. In the binary mixtures the components interact and the difference between the diffusion rates of the components decreases. The MFI zeolite presents equilibrium selectivity towards the less branched isomers. In conclusion, a separation process for inear/mono-branched alkanes + double-branched alkanes, has to be based on its equilibrium properties and not based on adsorption kinetics.
Subject: Ciências Tecnológicas, Outras ciências da engenharia e tecnologias
Scientific areas: Ciências da engenharia e tecnologias::Outras ciências da engenharia e tecnologias
Document Type: Artigo em Revista Científica Internacional
Rights: restrictedAccess
Appears in Collections:FEUP - Artigo em Revista Científica Internacional

Files in This Item:
File Description SizeFormat 
  Restricted Access
626.24 kBAdobe PDF    Request a copy

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