[en] X-ray microtomography coupled to image analysis has been used to study the influence of the adsorbent pore texture and the experimental conditions on the dynamic adsorption of methyl iodide in packed filters. By applying this imaging technique the internal axial adsorption profiles for increasing exposure times to the gas stream are analysed. This experimental technique establishes a new technology to study in situ the dynamic adsorption of volatile compounds. Resorcinol-formaldehyde based carbon xerogels have been used as adsorbents, as their pore texture can be tuned by changing the synthesis conditions. The textural characteristics of the adsorbents (surface areas and pore volumes) have been assessed by using nitrogen and carbon dioxide adsorption as well as mercury porosimetry. The methyl iodide dynamic adsorption results show that, for the same gas flow rate and CH3I inlet concentration, the adsorbed amount is highly dependent on large pore volumes. Thus, samples with almost the same micropore volumes (adsorption volumes) have different methyl iodide adsorption capacities, which are related to, the above mentioned, large pores. The influence of both the gas carrier flow rate and the methyl iodide inlet concentration on the adsorption can be explained using the so-called linear driving force model. This approach takes into account the fact that internal transport limitations are directly related to the pore texture. Moreover, the simulation of the dynamic adsorption process has allowed relating the simulated axial concentration profiles to the experimental X-ray microtomography data.
Disciplines :
Chemical engineering
Author, co-author :
Almazán-Almazán, M. C.
López-Domingo, F. J.; Universidad de Granada (España) = University of Granada (Spain) - UGR > Departamento de CCIA > ETS de Ingeniería Informática y Telecomunicación
Domingo-García, M.; Universidad de Granada (España) = University of Granada (Spain) - UGR > Departamento de Química Inorgánica
Léonard, Angélique ; Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Procédés et développement durable
Pérez-Mendoza, M.; Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Génie catalytique
Pirard, Jean-Paul ; Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Génie catalytique
López-Garzón, F. J.; Universidad de Granada (España) = University of Granada (Spain) - UGR > Departamento de Química Inorgánica
Blacher, Silvia ; Université de Liège - ULiège > Département des sciences cliniques > Labo de biologie des tumeurs et du développement
Language :
English
Title :
Influence of carbon xerogel textural properties on the dynamic adsorption of methyl iodide
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