EXAMPLE 12.1 Ray and Box [Ind. Eng. Chem., 42(1950) 1315] reported the following data on adsorption of pure propane on Columbia grade L activated carbon at different temperatures and pressures. p= pressure of propane (kPa);q= amount of propane adsorbed at equilibrium (millimol/g carbon). (a) Draw the adsorption isotherms ( q vs. p ) at the above four temperatures, and the adsorption isosters (ln p vs. 1/T ) at constant solute loadings of q=2.0,2.5,3.0 and 3.5(mmol/g carbon). (b) Test the applicability of the Langmuir and the Freundlich isotherms for the given data. (c) Determine the isosteric heat of adsorption