Thermodynamic approach to the surface area and pore size analysis of active carbons

摘要

Application of the adsorption potential distribution (APD) to calculate the average micropore width and the specific surface area is discussed. The monolayer capacity is evaluated from the amount adsorbed corresponding to the minimum between the monolayer formation and secondary mi8cropore filling peaks on APD. Thus obtained monolayer capacity is used to calculate the specific surface area, which in turn allows one to evaluate the average micropore size from the micropore volume, assuming slit-like pore geometry. It is shown that low-pressure nitrogen isotherms and APDs for various activated carbons and activated carbon fibers with similar average micropore sizes are very analogous. This suggests that different microporous carbons may have similar microporous structures and similar widths of micropore size distributions.