Research group Crystallization and Membrane Processes


Head of group: Prof. Dr. Axel König

Membrane-Assisted Thermal Separation Processes

Membrane modules

One of the main focuses of this research group is the combination of membrane processes and conventional thermal separation technology with the aim to generate a kind of hybrid processes. Against this background, membrane-assisted extraction, absorption, stripping and pertraction are examined. Membrane-assisted distillation and crystallization are also main tasks.

Furthermore, we design and build our own flat and capillary membrane modules (so-called membrane contactors) which we use in our experimental setups. Beyond the experimental part, the modeling and simulation of the underlying transport phenomena and processes is of high significance in this research group. Thus, experimental values are compared to the calculated ones or used as boundary conditions in the calculations respectively. Consequently these values are used for process development, too.

Industrial Crystallization Processes


On the one hand the crystallization section in our department deals with purification and ultra-purification of e. g. ionic liquids by melt crystallization, layer and suspension crystallization techniques, thermometrical investigations and crystal size distribution determinations via photo-centrifuge. In addition, nucleation and crystal growth kinetics are estimated.

On the other hand crystallization as a thermal separation technique is combined with membrane processes like membrane distillation. This concept allows well-controlled crystallization because the generation of the supersaturation is controlled and adjusted respectively. With the aim to design process applications, the coupled system of generation and degradation of supersaturation is modeled and simulated by means of solving partial differential equation systems.

Trinkwasser - Eine globale Herausforderung (Lange Nacht der Wissenschaften 2007)

Poster I

Poster II

Current Research Topics

Ionic liquids

Paper: Ionic Liquids - Cation analysis using ion chromatography

Paper: Ionic Liquids - Anion analysis using ion chromatography

Paper: Ultrapurification of Ionic Liquids by melt crystallization

Poster: Production of valuable ILs by membrane dialysis

Poster: Analysis of complex IL mixtures using IC

Abstract:_Bipolar Membrane Electro Dialysis

Abstract:_Production of valuable ionic liquids

Membrane based crystallization

Poster - Produktdesign durch membrangestützte Antisolventkristallisation (Posterpreis ProcessNET-Jahrestagung 2007)

Paper: Membrane Based Evaporation Crystallization

Poster:_Membrane Based Evaporation Crystallization

Poster: Aufarbeitung von gipsgesättigten Lösungen

Abstract:_Membrandialyse zur Fällung definierter BaSO4-Kristalle

Abstract:_Membrangestützte Kristallisation von NaCl

Crystallization kinetics

Poster:_Untersuchungen zur Auflösekinetik von Kaliumchlorid

Abstract:_Untersuchungen zur Auflösekinetik von Kaliumchlorid


Poster:_Orangensaftkonzentrierung durch Umkehrosmose