The petrochemical industry is confronted with the requirement for thermodynamic data on complex phase equilibrium problems for enhanced oil recovery (EOR), and COSMOtherm has proved to be a useful tool when solving these problems. As a first-principles based prediction method, COSMOtherm can be used either to directly calculate thermodynamic properties or as a foundation to build new models based on the physically meaningful  COSMOtherm results or descriptors.

Predicted properties

  • Partition coefficients of polar ingredients
  • Extraction and liquid-liquid equilibria
  • Solubility and solid-liquid equilibria
  • Gas solubility and vapor pressures of complex mixtures
  • Adsorption models
  • Interfacial tension
  • Pure compound density and viscosity
  • Mixture phases containing surfactants, polymers and ionic liquids

Use COSMOtherm to:

  • Predict equilibrium properties of complex liquid mixtures
  • Achieve the best possible solutions and optimize their processes
  • Predict properties where no experimental data is available
  • Plan experimental setups and reduce laboratory time
  • Complement other theoretical and experimental data models

Relevant features for the oil industry

Phase equilibria and extraction

The COSMOtherm software provides a wide variation of solution methods for phase equilibrium problems between liquid, gaseous and solid phases. Complex tasks, such as multicomponent and multiphase extraction equilibria or vapor-liquid separations with entrainers that shift or break azeotropes, can be modeled in a straightforward and simple manner.

Solvent screening

With the solvent screening capabilities, the optimum solvent, the best anti-solvent, or the most selective solvent for extraction or downstream processes can be identified. Virtual pre-screening over a large database of solvents can reduce the required amount of measurements and even support the development of new improved solvents. 


COSMOtherm utilizes one of the few theoretical models that can predict thermodynamic properties of systems containing surfactants. With the plug-in COSMOmic it is even possible to predict some important properties of micellar systems.

Polymers & adsorption

Compounds with unspecified molar weight such as polymers, or complex matrices such as activated carbon can be treated by COSMOtherm, although some additional effort is required to obtain quantitative predictions. For example, it is possible to treat adsorption to a complex matrix via empirical QSPR models that use descriptors obtained from COSMOtherm. Some properties of polymers such as solubility in the polymer can be predicted accordingly in a qualitative, or, with some additional effort, semi-quantitative manner. See also polymer applications

Interfacial tension (IFT)

COSMOtherm can be used to predict the interfacial tension not only between water and organic compounds, but also between mixtures and non-water two-phase systems. To achieve this, several methods has been implemented, where the simpler approaches are based on empirical relations to predicted water / organic phase separation, and the more advanced model utilizes the FlatSurf functionality of COSMOtherm.
Please refer to
DOI: 10.1021/ct500266z and DOI: 10.2118/169663-MS for details.

Ionic liquids

COSMOtherm is the only method that predicts the thermodynamic properties of ionic liquids in the same way and with the same accuracy as any other class of compounds. Because cations and anions of ionic liquids are treated as independent species, large screening tasks can accomplished quite easily. More on ionic liquids.

Process modeling & engineering simulation

Process modeling & engineering (PME) simulations can be provided with predicted thermodynamic data in the form of activity coefficient model parameters such as NRTL, UNIQUAC, or Wilson’s equation. Alternatively cou can feed the PME with COSMOtherm's CAPE OPEN interface.