FRACTAL DIMENSION OF MICROPOROUS ACTIVATED CARBON FROM HENRYS LAW OF ADSORPTION

The method of determination of the factal dimension (D) from adsorptio n isotherms at low coverages, developed by Cole, Holter and Pfeifer, w as verified experimentally. The temperature dependence of adsorption o f CH2Cl2, CH3CN and CH3NO2 on microporous carbon was measured using ga s chromatography in the Henry's law region. The main problem of the th eoretical approach for fractal dimension determination is the using of correct adsorbate diameter. However, the acquaintance of the chemical surface nature of an investigated material may provide a probable arr angement of adsorbed molecules on the surface and may lead to determin ation of their diameters using structural data of molecules. Despite t his difficulty the procedure seems to be successful and leads to the f ractal dimension of investigated carbon equal to 2.398.