The challenges for the aftertreatment of fuel vapor in adsorbers of petrol-engined passenger cars are increasing considerably due to the steady tightening of emission control laws. For the total work capacity of an adsorber, the sorption ability of the included adsorbent is crucial and, in turn, depends heavily on the particular fuel vapor being adsorbed. The corresponding adsorptive mixtures are analyzed by means of characterizing representative fuels. On this basis, characteristic material properties are compared and, thus, various adsorbents are evaluated.