Adsorption of nitrogen on thermally treated peat soils: The role of energetic and geometric heterogeneity

We investigate adsorption isotherms of nitrogen at 80 K on several peat soi ls. In addition to natural soil samples we also study samples thermally tre ated at 50, 100, and 150 degrees C. The experimental adsorption isotherms a re used to evaluate the surface fractal dimension and the energy distributi on functions. Moreover, for some samples we have also determined the pore s ize distributions from mercury intrusion data. We compare the surface fract al dimensions evaluated from the mercury intrusion data and from adsorption isotherms and discuss how the thermal treatment changes the energetic hete rogeneity of the samples. (C) 1999 Academic Press.