Influence of the Pore Geometry on the Micropore Size Distribution Function of Active Carbons

A simple procedure for the evaluation of the micropore size distribution function of active carbons from the experimental adsorption isotherm of a single gas is discussed. In this method, the adsorption potential distribution and the dependencies of this potential on the micropore size for three different models, i.e. slit-like, cylindrical and spherical, are utilized. It was shown that the geometrical shape of pores may have a substantial influence on the micropore size distribution. While the micropore size distributions calculated assuming slit-like and cylindrical pore geometries are similar, spherical pore geometry leads to a substantially different distribution. A qualitative agreement was found between the micropore size distribution obtained by the current procedure, which is equivalent to the Horvath–Kawazoe method, and that evaluated by the density functional theory (DFT) method.