Abstract: The heat of adsorption was derived from the temperature dependence of retention time for eluted peaks on a series of carbonated (pyrolyzed) resins.In view of chromatographic kinetics and thermodynamics the separative power, selectivity of the carbonaceous adsorbents and the factors influencing column efficiency are discussed theoretically.It is found that the diffusion effect controlled by inner structure of the adsorbent particle is the basic reason affecting separation and column efficiency.The conditions under which useful adsorbent could be made are revealed.