Effect of micropore size distribution induced heterogeneity on binary adsorption kinetics of hydrocarbons in activated carbon

摘要

Experimental data of sorption kinetics of ethane and propane and their binary mixtures on Norit activated carbon under various conditions were measured using a differential adsorber bed (DAB) rig and used to further validate the predictive capability of the kinetic model proposed by Hu, Qiao and Do (1999, Langmuir). The model utilizes the concept of micropore size distribution and Lennard-Jones potential theory to describe the adsorption energetic heterogeneity on activated carbon. The pore size distribution is treated as the intrinsic property of adsorbent and taken as the sole source of solid surface heterogeneity. A gamma distribution is used to describe the micropore size distribution. The size exclusion effect is taken into account in the competition of different species for a given pore. The effect of the minimum size of pore accessible to different adsorbates on kinetics prediction is investigated. The requirement of thermodynamic consistency for adsorption equilibrium model is also studied in simulating the multicomponent adsorption kinetics. (C) 2000 Elsevier Science Ltd. All rights reserved. [References: 25]