Js. Porto et al., ADSORPTION DYNAMICS OF BENZENE ON ACTIVATED CARBON IN THE PRESENCE OFSUPERCRITICAL CARBON-DIOXIDE, Journal of Chemical Engineering of Japan, 28(4), 1995, pp. 388-392
The dynamics of adsorption of benzene dissolved in supercritical carbo
n dioxide on activated carbon were studied by analysis of breakthrough
curves in the nonlinear region of the adsorption isotherm, The column
was long enough to ensure constant pattern conditions, and the shapes
of the experimental breakthrough curves were used for identification
of the controlling mass transfer processes, The effects of intrapartic
le diffusion and external mass transfer were investigated by numerical
solution of the corresponding differential equations, Surface diffusi
on was found to be the main transport mechanism inside the adsorbent p
articles. No considerable variation of the effective surface diffusivi
ty was observed in the range of experimental conditions, and the measu
red values are in the order 10(-10)m(2)/s.