Collaborative Research Center/Transregio 63

"Integrated Chemical Processes in Liquid Multiphase Systems"

>Research>Completed Projects>Project A8 E

A8 Thermodynamics of Crystallization and Adsorption of Linear and Branched Molecules (completed)

Sub-Coordinators: Dr.-Ing. Tim Zeiner, Prof. Dr. Sabine Enders
Researcher: M.Sc. Thomas Goetsch

State of the art

The separation of long chain isomers or mono- and diester is a special challenge as distillation is very elaborative because of the small separation factor and extraction processes do not match the high purity demands. In principal this separation task can be achieved by processes based on crystallization or liquid chromatography. For the design of these processes thermodynamic data is necessary, but this data cannot be measured as the branched molecules are not commercially available in the needed purity. Furthermore a lot of experiments are necessary to find an appropriate adsorption material for the liquid chromatography.

Research goals

The goal is to develop the physical knowledge of a process model for the separation of long chain molecules with different architectures. To consider the influence of branching on thermodynamic phase behavior the Lattice Cluster Theory (LCT) is used to consider architectural influence of linear and branched molecules. This framework forms the basis for the modeling of crystallization of linear and branched molecules. The results are verified by selected experiments. The combination of the LCT with the density functional theory aims to the development of a method to predict adsorption isotherms of mixtures based on adsorptions isotherms of pure components.

More information
  • Application of innovative materials for the  separation of complex molecules in extraction and adsorptive processes
  • process concepts for the use of renewable components
  • Phase equilibria and interfacial properties of complex mixtures


Recent Publications

Goetsch, T.; Zimmermann, P.; Scharzec, B.; Enders, S.; Zeiner, T. Adsorption Isotherms of Liquid Isomeric Mixtures. Ind. Eng. Chem. Res., 57, 11210-11218, 2018. [DOI: 10.1021/acs.iecr.8b02296]

Zimmermann, P.; Walowski, C.; Enders, S. Impact of higher order diagrams on phase equilibrium calculations for small molecules using Lattice Cluster Theory. Journal of Chemical Physics, 148, 94103, 2018. []


Butz, J.; Zimmermann, P.; Enders, S. Impact of the equation of state on calculated adsorption isotherm using DFT. Chem. Eng. Sci., 171, 513-519, 2017. []

Goetsch, T.; Zimmermann, P.; van den Bongard, R.; Enders, S.; Zeiner, T. Superposition of Liquid–Liquid and Solid–Liquid Equilibria of Linear and Branched Molecules: Ternary Systems. Ind. Eng. Chem. Res., 56(1), 417-423, 2017. [doi: 10.1021/acs.iecr.6b04253]

Goetsch, T.; Danzer, A.; Zimmermann, P.; Kohler, A.; Kissing, K.; Enders, S.; Zeiner, T. Liquid-Liquid Equilibrium and Interfacial Tension of Hexane Isomers-Methanol Systems. Ind. Eng. Chem. Res., 56, 9743-9752, 2017. [doi: 10.1021/acs.iecr.7b02099]

Kruber, K. F.; Krapoth, M.; Zeiner, T. Interfacial mass transfer in ternary liquid-liquid systems. Fluid phase Equilibria, 440, 54-63, 2017. []

Zimmermann, P.; Goetsch, T.; Enders, S. Modelling of adsorption isotherms of isomers using density functional theory. Mol. Phys., 115(9-12), 1389-1407, 2017. [doi:]


Goetsch, T.; Zimmermann, P.; Enders, S.; Zeiner, T. Tuneable extraction systems based on hyperbranched polymers. Chem. Eng. Process., 99, 175-182, 2016. [doi:10.1016/j.cep.2015.07.021]

Goetsch, T.; Zimmermann, P.; van den Bongard, R.; Enders, S.; Zeiner, T. Superposition of Liquid-Liquid and Solid-Liquid Equilibria of Linear and Branched Molecules: Binary Systems. Ind. Eng. Chem. Res., 55(42), 11167-11174, 2016. [doi: 10.1021/acs.iecr.6b02798]

Zimmermann, P.; Goetsch, T.; Zeiner, T.; Enders, S. Prediction of adsorption isotherms on n-aldehydes mixtures using density functional theory in combination with Peng-Robinson equation of state. Fluid Phase Equilib., 424, 173-181, 2016. [doi:10.1016/j.fluid.2016.04.006]


Riechert, O.; Husham, M.; Sadowski, G.; Zeiner, T. Solvent effects on esterification equilibria. AIChE J., 61(9), 3000–3011, 2015. [doi:10.1002/aic.14873]


Kulaguin Chicaroux, A. Phasengleichgewichte und Stofftransport in polymerbasierten wässrigen Zwei-Phasen Systemen. Technische Universität Dortmund, 2016. [More]

Last updated:18-01-2022