MEASUREMENT OF EFFECTIVE DIFFUSIVITIES OF TOLUENE IN ACTIVATED CARBON IN THE PRESENCE OF SUPERCRITICAL CARBON-DIOXIDE

The effective diffusivities of toluene in supercritical carbon dioxide in activated carbon pellets were measured from the sorption curves of toluene in a spinning basket reactor at temperatures 308, 318, and 328 K and pressures up to 163 bar. It was observed that the effective diffusivities at supercritical conditions were strongly dependent on carbon dioxide density but weakly dependent on temperature and the amount of toluene adsorbed. The equilibrium amount of toluene adsorbed on activated carbon was also obtained from the sorption rate experiment which could be correlated by the Toth isotherm expression.