Abstract
Sorption from the vapor phase is an important factor controlling the transport of volatile organic compounds (VOCs) in the vadose zone. Therefore, an accurate description of sorption behavior is essential to predict the ultimate fate of contaminants. Several measurement tech- niques are available in the case of water, however, when dealing with VOCs, the determination of sorption characteristics generally relies on gas chromatography. To avoid some drawbacks associated with this technology, we propose a new method to determine the sorption isotherm of any liquid compounds adsorbed in a soil. This method is based on standard and costless transducers (gas pressure, temperature) leading to a simple and transportable experimental de- vice. A numerical estimation underlines the good accuracy and this technique is validated on two examples. Eventually, this method is applied to determine the sorption isotherm of three liquid compounds (water, heptane and trichloroethylene) in a clayey soil.