Porous structure of activated carbons and tert-butylbenzene breakthrough dynamics

The structural and adsorptive characteristics of six activated carbons were studied by means of nitrogen and benzene adsorption and water desorption. Tert-butylbenzene (TBB) breakthrough dynamics was analyzed by using several integral equations solved with a regularization/singular-value decomposition procedure. TBB interaction with texturally different activated carbons with the presence of preadsorbed or adsorbed water under dynamic conditions was illustrated by the breakthrough plots handled with several models. The influence of the type of activated carbons, their pore size distributions, water vapor, and TBB flow rate on the breakthrough times (0 and the dynamic capacity of the carbon beds has been explored with better results for a carbon sample possessing a maximal contribution of mesopores at half-width x > 1.5 nm among the carbons studied (which also appears on benzene adsorption) and a major contribution of microporocity as V-Ds/V-p approximate to 0.88 and S-K/S-BET approximate to 0.15. Another adsorbent, which is characterized by a similar total porosity but a larger micropore volume, a smaller contribution of mesopores (S-K/S-BET approximate to 0.08), greater total and miroporous specific surface areas, and greater intensity of the pore size distribution at x < 1.5 nm, shows the second result in dynamic TBB retention. (C) 2002 Elsevier Science (USA).