Comparative study of gas adsorption and small angle X-ray scattering by active carbons, in relation to heterogeneity

A comparative study of selected active carbons shows that the spread of the structural parameter <i>B</i>, implied by the generalized adsorption equation of Stoeckli, is compatible with the spread of the Guinier gyration radii suggested by the small-angle scattering of X-rays. In the case of a molecular-sieve carbon having a large micropore volume, there is no spread for either parameter. It is suggested, that all available SAXS and adsorption data should be reconsidered in terms of continuous distributions.