Optimization of integrated reaction/separation processes for the kinetic resolution of rac-1-phenylethanol using supported liquid membranes based on ionic liquids
Special Symposium - EPIC-1: European Process Intensification Conference - 1
EPIC-1: Poster Session (EPIC - Poster) - P1
Keywords: kinetic resolution, supported liquid membranes, process integration, ionic liquids, lipase
Optimization of integrated reaction/separation processes for the kinetic resolution of rac-1-phenylethanol using supported liquid membranes based on ionic liquids
A. P. de los Ríos*, F. J. Hernández-Fernández, F. Tomás-Alonso, D. Gómez, M. Rubio and G. Víllora
Department of Chemical Engineering , Faculty of Chemistry, University of Murcia,P.O. Box 4021, Campus de Espinardo, E-30100, Murcia, Spain.
E-mail: aprios@um.es
Enantiopure compounds have undoubtedly gained a vital role in the develop of modern chemical technology. From among many methods for obtaining such enantiomerically pure compounds, the processes performed in the enzymatic membrane reactors are considered as especially useful [1]. These reactors integrate the enantioselective catalytic action of the enzyme and the selective permeability of the compounds. The use of room temperature ionic liquids (ILs) as an immobilized phase in a supporting membrane is particularly interesting due to the non-volatile character of the ILs and their solubility properties in the surrounding phases, which makes it possible to obtain very stable supported liquid membranes without any observable loss of the IL to the atmosphere or the contacting phases [2].
The present work studies the kinetic resolution of rac-1-phenylethanol catalysed by a commercial immobilized Candida antarctica lipase B (Novozym 435) using a membrane bioreactor containing a supported liquid membrane based on ionic liquids. In previous works, the reaction [3] and separation processes [4] were studied separately, which allowed us to choose optimal reaction and separation conditions to be used in the integrated reaction/separation process. The integrated reaction and separation experiments were carried out in a glass diffusion cell with two independent compartments of equal volumes separated by the SLM.
First of all, the effect of enzyme concentration in the reaction compartment on the efficiency of the process was studied. It was observed an increase in the efficiency of the process with increasing concentration of the enzyme within the experimental interval. Furthermore, the effect of different vynil esters used as acyl-donor was also analysed. The efficiency of the process enhanced with the increasing in alkyl chain length of the vynil ester.
In conclusion, the best conditions for the kinetic resolution of rac-1-phenylethanol in an integrated reaction separation process was found, in which propionic acid is nearly not produced and the product reaction ((R)-1-phenylethylpropionate) is separated from unreacted (S)-enantiomer ((S)-phenylethanol).
Acknowledgements:
This work was partially supported by the CICYT CTQ2005-09238/PPQ.
References:
[1] Wu D.R., Cramer S.M., Belfort G. (1993). Biotechnol. Bioeng. 41, 979-992.
[2] L. C. Branco, J. G. Grespo, C. A. M. Afonso, Chem. Eur. J. 2002, 8, 3865-3871.
[3] F. J. Hernández, A. P. de los Ríos, M. Rubio, D. Gómez, F. Tomás-Alonso, G. Víllora. (2007). Communication in “Chemical Reaction Engineering XI: Green Chemical Reactor Engineering”, Accepted.
[4] F.J.Hernández, A.P. de los Ríos, E. Heinen, M. Rubio, F. Tomás-Alonso, D. Gómez, G. Víllora. (2006). Communication in “6th ANQUE International Congress of Chemistry and Sustainable Development”, T2-76.
Presented Wednesday 19, 13:30 to 14:40, in session EPIC-1 Poster Session (EPIC - Poster) - P1.
