Adsorption of ethanol onto parent and surface treated activated carbon powders

Abstract

In this paper, adsorption isotherms and kinetics of ethanol onto highly porous activated carbon powders have been investigated. Adsorbents used in the present study are (i) parent Maxsorb III, (ii) KOH-H2 treated Maxsorb III, and (iii) H2 treated Maxsorb III. Adsorption isotherms and kinetics of the assorted pairs have been measured using magnetic suspension adsorption measurement unit (MSB-VG-S2). Experiments have been conducted across assorted adsorption temperatures that are useful for the operation of adsorption chillers. The Dubinin-Astakhov equation is used to fit adsorption isotherms of parent Maxsorb III/ethanol and KOH-H2 treated Maxsorb III pairs whilst the Dubinin-Radushkevich isotherm model is found to be more suitable for fitting of adsorption uptake of H2-treated Maxsorb III/ethanol pair. Adsorption kinetics of assorted pairs are presented by the Fickian diffusion model. Experimental results show that, among the assorted pairs, H2 treated Maxsorb III/ethanol pair possesses the highest adsorption equilibrium uptake. However, the diffusion time constant of KOH-H2 treated Maxsorb III is found to be higher than that of other two studied pairs. © 2014 Elsevier Ltd. All rights reserved.