Characteristic Adsorption Curve on Activated Carbon in Gas and Liquid Phases

Abstract

The characteristic adsorption curves on activated carbon with different pore size distributions have been determined in gas and liquid phases. The adsorption isotherms of benzene in gas phase were measured and the parameters in the Dubinin-Astakhov equation were calculated. The linear relationship exists between n_G and E_G. The adsorption volume (W_G) was calculated from the limiting vapor adsorption at P/P₀→1. The linear relationships exist between W^O_G/W_G and n_G or E_G. In liquid phase, the adsorption isotherms of anisole from aque ous solution were measured and correlated by the following equation:
where ε s1 =R T In Cs/C, Cs is solubility, and C an equilibrium concentration. The linear relationship exist between nL and E_L, and between W^O_G/W_G and n_L or E_L. The values of n and E in liquid phase are smaller than those in gas phase. The magnitude of W^O_L is similar to that of W^O_G. This suggests that in liquid phase, pores, having such large diameters as occur capilary condensation, are also utilized for an adsorption.