Horvath-Kawazoe method limitation

Pore Size Distribution. As mentioned earlier, NLDFT and GCMC are considered to be the most accurate methods for micro- and mesopore size analysis. Their application is limited by the availability of kernel isotherms. Although semiempirical analytical methods may fill the gap, it is however worthwhile to recall that these methods often underestimate the pore sizes for a given equilibrium pressure. The approach of Horvath and Kawazoe (HK) is based on a fundamental statistical analysis of a fluid confined to a slit-shaped pore (24). An extension of this method to cylindrical and spherical pore models was made by Saito and Foley (SF, (25)) and Cheng and Yang, respectively (26). 

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