Jürgen Gmehling

Jürgen Gmehling (born January 13, 1946 in Duisburg) is a German professor for technical and industrial chemistry at the Carl von Ossietzky University of Oldenburg.

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Biography

His career startet with an apprenticeship as laboratory assistant at the Duisburg copper works before he studied chemical engineering at the engineering school in Essen and then chemistry in Dortmund and Clausthal. He received his diploma from the Dortmund University in 1970 and the Ph.D. (Dr. rer. nat., inorganic chemistry) in 1973. After this he worked as scientific coworker in Dortmund before he became a private lecturer and, after his habilitation, an assistant professor.

Gmehling was appointed full professor for technical chemistry at the university in Oldenburg in 1989.

Fields of research

Gmehling's main focusses are measurement, collection and estimation of thermophysical properties of components and component mixtures. The following list summarizes several fields of his scientific work in a concise manner but is in no way complete.

Measurements

• Phase equilibrium data (vapor-liquid equilibria,^[1] liquid-liquid equilibria, solid-liquid equilibria,^[2] gas solubilities, heats of mixing, activity coefficients^[3] and more)
• Pure component properties (heats of phase transitions, vapor pressures, densities, viscosities)
• Kinetics of reaction (heterogeneous catalysis)

Data collection

Gmehling began in the 1970s with the systematic evaluation of the scientific literature with the goal to build a data bank for vapor-liquid equilibria. These data were needed for the development of a new method for the prediction of activity coefficients named UNIFAC. This data bank is still named Dortmund Data Bank,^[4] although it has expanded dramatically over the last decades, and is now maintained by a company located in Oldenburg.

Development of estimation and correlation models

Gmehling developed, together with coworkers and in cooperations, especially Professor Aage Fredenslund from the Danmarks Tekniske Universitet, models for the estimation of several thermodynamic and thermophysical properties:

• Activity coefficient models like UNIFAC^[5][6] (see group contribution methods) and extensions. For the further development of these widely used methods Gmehling founded an industry consortium where many international companies are participating.
• Equations of state (EOS)^[7] including mixing rules for applying EOS to mixtures.
• g^E models
• Prediction of pure component properties (normal boiling point, liquid viscosity, critical data)

Software development

Considerable developments are besides the implementation of his own methods

• an expert system^[8] for the entrainer selection for the azeotropic and extractive distillation.
• programs for fitting parameters of g^E models and many equations describing pure component properties

Other fields of work

Gmehling is also working on the research and optimization of chemical processes like reactive distillation and membrane processes.

Prices

Gmehling received the Arnold Eucken price from the GVC (VDI society for chemical engineering).

Company foundations

Gmehling has founded two companies:

• The DDBST GmbH has been founded in 1989. Its main purpose is the further development of the Dortmund Data Bank.
• The LTP GmbH has been founded in 1999. The main purpose is the experimental determination of thermophysical data.

Publications

Gmehling has published, besides numerous scientific articles, several books. These are textbooks (e.g. Thermodynamics and Unit Operations) as well as data collections that have been published by the DECHEMA (DECHEMA Chemistry Data Series, DCDS) and the publishers Wiley-VCH (Azeotropic Data).

Selection of scientific articles

1. ^ Horstmann S., Fischer K., Gmehling J., "Isothermal Vapor-Liquid Equilibrium and Excess Enthalpy Data for the Binary Systems Water + Sulfolane and Methanol + N-Methyl-2-pyrrolidone", J.Chem.Eng.Data, 49(6), 1499-1503, 2004
2. ^ Joh R., Kreutz J., Gmehling J., "Measurement and Prediction of Ternary Solid-Liquid Equilibria", J.Chem.Eng.Data, 42(5), 886-889, 1997
3. ^ Gruber D., Topphoff M., Gmehling J., "Measurement of activity coefficients at infinite dilution using gas-liquid chromatography. 8. Results for 22 solutes in tetraethylene glycol dimethyl ether and 18 solutes in triethylene glycol dibutyl ether at 303.15 K and 343.15 K", Eldata Int.Electron.J.Phys.-Chem.Data, 3, 215-224, 1997
4. ^ Gmehling J., Weidlich U., "Die Dortmunder Datenbank. Basis für die Weiterentwicklung der UNIFAC-Methode", Chem.Ing.Tech., 57(5), 447-449, 1985
5. ^ Fredenslund Å., Gmehling J., Michelsen M.L., Rasmussen P., Prausnitz J.M., "Computerized Design of Multicomponent Distillation Columns Using the UNIFAC Group Contribution Method for Calculation of Activity Coefficients", Ind.Eng.Chem. Process Des.Dev., 16(4), 450-462, 1977
6. ^ Weidlich U., Gmehling J., "A Modified UNIFAC Model. 1. Prediction of VLE, hE, and gamma Infinite", Ind.Eng.Chem.Res., 26(7), 1372-1381, 1987
7. ^ Holderbaum T., Gmehling J., "PSRK: A Group-Contribution Equation of State based on UNIFAC", Fluid Phase Equilib., 70, 251-265, 1991
8. ^ Möllmann C., Gmehling J., "Auswahl selektiver Zusatzstoffe für die Rektifikation durch kombinierten Zugriff auf experimentelle und vorausberechnete Gleichgewichtsdaten", Chem.Ing.Tech., 69(3), 324-328, 1997

Reviewing

Gmehling is co-publisher of three scientific journals and reviewer for several others. Additionally he has been reviewing scientific projects for the German (Deutsche Forschungsgemeinschaft), Czech, Finnish, and Slowenian scientific societies.