Carbonaceous adsorbents produced from mixtures of novolac resin and olive stone biomass in various proportions were investigated with respect to their ability to adsorb toluene and cyclohexane from the vapour phase. The adsorption of toluene on all adsorbents was found to be higher than that of cyclohexane. The overall diffusion coefficient, D, of the adsorption process, the specific surface area and the pore volume of the adsorbents have been calculated. The results are discussed in terms of the size and shape of the pores, the polarity of the adsorbate and the dispersion forces between adsorbent and adsorbate. It is concluded that slit-shaped pores are also present in the adsorbents which are characteristic of carbon molecular sieves. Toluene can enter more pores than cyclohexane for the adsorbents used. The adsorbent derived from the mixture of novolac/biomass=20/80 shows the highest adsorption (i.e. equilibrium uptake, diffusion coefficient, specific surface area and pore volume) of toluene and cyclohexane.