Oil spillage and discharge of organic solvents are not only an environmental and ecological problem but also an economical issue. In the recent, open cell hydrophobic/oleophilic foams have been shown to be a promising candidate to clean up the floating oils and water-insoluble organic solvents by efficient sorption. Most of the current studies focus on the fabrication of advanced porous foams with superhydrophobicity/superoleophilicity. There are few works paying attention to the thermodynamics and kinetics of the sorption processes. Here, we provide a systematic analysis to clarify the intrinsic nature of sorption capacity and kinetics associated with the oil and organic solvent sorption into open cell foams. Kinetic models derived from surface adsorption (e.g., pseudo first- and second-order rate models) are widely used to fit the kinetics data of oil sorption into the open cell foams. This is a misapplication of adsorption kinetic models by confusing surface adsorption and bulk absorption. In fact, the oil sorption into the open cellular foams is a capillary phenomenon. Therefore, the Beltran equation (Br. Ceram. Trans. J., 1988, 87: 64) developed to describe liquid penetration into cylindrical capillaries was used to fit the sorption kinetics data and the validity of that equation in oil sorption into open cell foams was verified by investigating the impacts of oil properties (i.e., density, viscosity and surface tension) and of bubble structure of the foams. The sorption capacity is another critical parameter when evaluating the performance of open cellular foams for the removal of oil spills and water-insoluble organic solvents. We measured the sorption capacity of a given stiff foam (not squeezable) for different oils and organic solvents and found that the volumetric sorption capacities for different liquids were statistically the same. These findings indicate that the sorption capacity of open cellular foams is mainly dependent on the void fraction of the f