On the surface diffusion of hydrocarbons in microporous activated carbon


Autoria(s): Do, H. D.; Do, D. D.; Prasetyo, I.
Contribuinte(s)

J. Bridgwater

Data(s)

01/01/2001

Resumo

This paper addresses the current status of the various diffusion theories for surface diffusion in the literature. The inadequacy of these models to explain the surface diffusion of many hydrocarbons in microporous activated carbon is shown in this paper. They all can explain the increase of the surface diffusivity (D-mu) with loading, but cannot explain the increase of the surface permeability (D(mu)partial derivativeC(mu)/partial derivativeP) with loading as observed in our data of diffusion of hydrocarbons in activated carbon, even when the surface heterogeneity is accounted for in those models. The explanation for their failure was presented, and we have put forward a theory to explain the increase of surface diffusion permeability with loading. This new theory assumes the variation of the activation energy for surface diffusion with surface loading, and it is validated with diffusion data of propane, n-butane, n-hexane, benzene and ethanol in activated carbon. (C) 2001 Elsevier Science Ltd. All rights reserved.

Identificador

http://espace.library.uq.edu.au/view/UQ:60162

Idioma(s)

eng

Publicador

Elsevier

Palavras-Chave #Engineering, Chemical #Surface Diffusion #Permeation Technique #Activated Carbon #Diffusion #Permeability #Heterogeneity #Energetically Heterogeneous Surfaces #Effective-medium Approximation #Molecular Gas-flow #Mesoporous Media #Concentration-dependence #Multilayer Adsorption #Condensable Vapors #1st Principles #Porous-media #Model Pores #C1 #250103 Colloid and Surface Chemistry #780102 Physical sciences
Tipo

Journal Article