ADSORPTION–CALORIMETRIC DETERMINATION OF THE SURFACE ENERGY OF DISPERSED OXIDES

A new method is proposed for the determination of the surface free energy _S and interfacial free energy sigma SL, based on their linear dependence on the specific heat of wetting of dispersed materials by water. The sigma S and sigma SL values of Silochrome, silica gel, and gamma-aluminum oxide were determined first by this method. The obtained results are compared with data obtained from the similarity method and the empirical relationship between sigma S and the surface pressure. It is demonstrated that the methods can be used to determine sigma S for the investigated sorbents. Conclusions about the hydrophilicity–hydrophobicity of their surface were reached on the basis of the results.