Adsorption hysteresis near saturation pressure for nitrogen on two carbon blacks

Abstract

Interparticle capillary condensation of nitrogen on standard graphitized carbon blacks, Sterling FT-G (2700) and Vulcan 3-G (2700), becomes extensive near saturation pressure at ca. 77 K. Using a simple model to describe the physical structure of these adsorbents, the relative pressures have been calculated for the fusion of adsorbate interparticle pendular rings. These values are in reasonable agreement with relative pressures corresponding to the lower closure points of each hysteresis loop.