KINETIC STUDIES ON ADSORPTION OF ODOR-CAUSING SUBSTANCES BY ACTIVATED CARBON

This study investigated the feasibility of removing 2-methylisoborneol (2-MIB) at the partsper-trillion (ppt) level from water by activated carbon (AC). The effect of carbon properties on the adsorption of 2-MIB by AC was evaluated using kinetic tests. The sorption kinetics was tested for the first-order reaction, pseudo-first-order, pseudo-second-order, and intraparticle diffusion models at different experimental conditions. The rate constants of sorption for all these kinetic models were calculated. Good correlation coefficients were obtained for the intra-particle diffusion model showing that the adsorption of 2-MIB onto AC is diffusion-controlled. The effective diffusion coefficient (De) was calculated using a heterogeneous diffusional mass transfer model. The De values are 0.74 to 1.69 × 10 -10 m 2 s -1 for 2-MIB adsorption on three ACs. The effective pore volume diffusivity was greater than the surface diffusivity of 2-MIB in aqueous solution, indicating that the overall rate of adsorption is mainly controlled by intra-particle diffusion.