PhOH, methylene blue and BuNH(2) were adsorbed from lig. or gaseous phases on kaolin, bentonite and 3 montmorillonites to compare their adsorption ability. Kaolin showed a low pore vol. and low adsorption capacity in all cases. The highest adsorption capacity was obsd. for montmorillonite balls (pore vol. 0.32 cm(3)/g, pore size 5.6 nm).