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The development of chemical engineering process technologies in recent years has led to an increase in the quantities of volatile organic compounds (VOCs) released into the atmosphere. Some of these VOCs such as ethylbenzene and n-hexane, in addition to being polluting, are found to be harmful to human health. Multiple techniques have been developed for the capture of these VOCs in ambient air. Adsorption processes are recognized as being very competitive for the removal of VOCs regarding the efficiency and the costs of its application. In this work, the adsorption equilibria of ethylbenzene and n-hexane in a commercial activated carbon (Norit RB4) was studied at the temperatures of 398 K, 423 K and 448 K and pressures between 0.01 up to 0.1 bar using gas chromatography. At the temperature of 398 K and partial pressure of 0.1 bar the sorption uptake capacity of ethylbenzene is around 2.34 mol.kg-1, with a heat of adsorption in the range of 50.0 ~ 59.5 kJ.mol-1. For similar conditions the n-hexane sorption uptake is smaller being around 1.61 mol.kg-1 with a heat of adsorption in the range of 52.5 ~ 59.2 kJ.mol-1. The experimental adsorption equilibrium data was modelled with the Langmuir, Freundlich, Sips, Toth and Redlich-Peterson adsorption isotherms. It is shown that the best isotherm model that fits the experimental data is given by the Toth isotherm for the ethylbenzene, while the Freundlich isotherm is best suited for n-hexane.