Characterization of modified activated carbons: Equilibria and dynamics studies Original Research Article

The effect of pore structure on the adsorption equilibria and dynamics of a commercial activated carbon has been investigated. Pore structure was varied by carefully activating the virgin carbon in CO2 atmosphere at 800 °C. We have found that surface area and micropore volumes generally increase with the degree of burn-off. Adsorption capacities of two sorbates, propane and benzene, are found to increase in the range of 0–10% burn-off, and decrease in the range 10–19%, beyond which they increase again. Within the range of burn-off studied in this investigation, this increase in the adsorption capacity was 22% for propane and 27% for benzene. These activated carbons of various degrees of burn-off are also evaluated in terms of their rate of adsorption of 10% propane at 30 °C. It was found that the rate of adsorption increases montonically with the degree of burn-off.