PHYSISORPTION OF GASES BY CARBON-BLACKS

Carbon blacks have been featured as model adsorbents in many fundament al investigations of gas adsorption. In particular, the use of graphit ized blacks has led to important advances in the understanding of adso rbent-adsorbate interactions and the interpretation of adsorption data . However, in the light of recent work it is necessary to reassess the significance of earlier isotherm and hear of adsorption measurements. Thus, not all carbon blacks behave as nonporous adsorbents, and in so me cases (for example, samples of Spheron 6) there is evidence of slig ht microporosity. Furthermore, the graphitized sur face generally exhi bits some degree of energetic heterogeneity. No current theory is able to provide a general mathematical description of physisorption isothe rms, and various empirical procedures are used for the analysis of exp erimental data. Caution must be exercised in the interpretation of der ived values of surface area and porosity.