Adsorption and desorption behaviour of toluene on activated carbon in a high gravity rotating bed

Rotating bed enables a fast transfer rate, which can promote the adsorption and desorption rates of processes. In this work, a rotating bed was used to adsorb toluene gas with activated carbon (AC) as the adsorbent. The influence of the operating parameters of a high gravity factor, gas flow, inlet concentration and bed thickness on adsorption rate were investigated, as were the influence of carrier gas temperature and rotational high gravity factor on desorption rate. The surface coverage and desorption rate of toluene from AC were determined to demonstrate the excellent performance of the rotating bed. In addition, the adsorption-desorption effect of the rotating bed was compared with the results of a fixed bed. The results showed that a rotating bed effectively increased the adsorption rate of toluene on AC and the desorption efficiency of AC compared with a fixed bed. AC in a rotating bed provided more effective adsorption sites, thereby improving the utilisation of AC; also, a desorption model showed that the rotating bed had a higher desorption rate and greatly reduced desorption time. In addition, AC in a rotating bed still exhibited excellent adsorption capacity after many adsorption-desorption cycles. Therefore, rotating bed can enable higher adsorption and desorption rates and effectively improve the utilisation of AC, providing an economical and environmentally friendly method. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.