In this article, we complete the study of size-scaling effects and of the Keller model, presenting a detailed analysis of the application of this model to a broad range of experimental data on microporous materials (in particular, activated carbon and zeolites). Particular attention is focused on the temperature dependence of the Freundlich exponents ai, on the functional form of the adsorption energies, and on the application of Keller adsorption isotherms in a predictive way to generic multicomponent mixtures.