Freundlich Adsorption Isotherm
(i) Freundlich adsorption isotherm is obeyed by the adsorptions where the adsorbate forms a monomolecular layer on the surface of the adsorbent.
(Freundlich adsorption isotherm) or
where x is the weight of the gas adsorbed by m gm of the adsorbent at a pressure p, thus x/m represents the amount of gas adsorbed by the adsorbents per gm (unit mass), k and n are constant at a particular temperature and for a particular adsorbent and adsorbate (gas), n is always greater than one, indicating that the amount of the gas adsorbed does not increase as rapidly as the pressure.
(ii) At low pressure, the extent of adsorption varies linearly with pressure.
(iii) At high pressure, it becomes independent of pressure.
(iv) At moderate pressure depends upon pressure raised to powers