Experimental Investigations of Different Unit Operations
1. Reactive Distillation
Reactive rectification is an interesting alternative to classical combinations of reactors and separation units (rectification, ...) especially in the case of reversible and consecutive chemical reactions. By performing reaction and separation simultaneously, it is possible to reach conversions far beyond equilibrium compositions.
A 10 meter column e.q. with a heterogeneous catalyst (Katapaks by Sulzer) is used for the production of methyl acetate. On the basis of thermodynamic and kinetic data determined with the help of different equipments (calorimeter, static stills, different type of reactors), the results are checked against simulation results. One of the aims is to decide, which unit operation models are applicable to solve the complex material and enthalpy balances for reactive distillation processes.
2. Membrane Processes
Membrane processes are of growing importance for the separation of multicomponent mixtures. With the help of a pervaporation apparatus, permeation rates e.g. of alcohol - water systems can be determined as function of various operating parameters using a hydrophobic solubility/diffusion membrane (PDMS). A microbalance was used for the measurement of solubilities and diffusion coefficients of the different components in the membrane.
3. Enzyme and Enantiomere Separation
Because of the denaturating effect of organic solvents, special polymer/salt/water 2-phase systems are discussed for the separation of bioproducts like for example enzymes. The applicability of these systems for separation processes is investigated with the help of liquid - liquid countercurrent chromatography (LLCCC).
The same technique (LLCCC) is also employed for the separation of enantiomers using a chiral selector in the stationary liquid phase.