Fixed-bed Adsorption of Trichloroethylene onto Activated Carbon

The present work deals with the study of the adsorption of Trichloroethylene (TCE) onto a commercial granular activated carbon (GAC). Thermodynamic (batch) and dynamic (fixed-bed column) tests were carried out, under a wide range of operating conditions. In particular, adsorption isotherms were preliminary determined to support the investigation on a fixed-bed column at lab-scale. The main fluid dynamic and physical parameters such as flow rate, TCE concentration and GAC particle size were investigated. Experimental data on fixed-bed column show that an increase in TCE initial concentration and, more markedly, an increase in flow rate lead to a shorter breakpoint time. In fact, the breakthrough curves become steeper as a consequence of higher velocity that enhances the external mass transport. Finally, a thorough modeling analysis of the fixed-bed column was carried out using a model that includes axial dispersion and external-film diffusion followed by internal diffusion. A good accordance between experimental data and model results was observed.