ISBN 978-3-8439-1373-7

978-3-8439-1373-7, Reihe Verfahrenstechnik

Francesca Santangelo
Ionic Liquids as extraction solvents for Biobutanol purification

169 Seiten, Dissertation Technische Universität Dortmund (2013), Softcover, B5

Zusammenfassung / Abstract

Biobutanol produced by fermentation has received considerable attention recently. Butanol recovery from fermentation broth through distillation is too costly. Extraction by ionic liquids (IL) can overcome this and is exploited in this research. An experimental approach by first screening different ILs with a simplified system (synthetic broth) through validating the obtained results by experiments using real fermentation broth is used. As assessment criteria for the selection of IL: distribution coefficient of butanol and side-products and the selectivity of the IL for butanol compared to water are applied in this work. As reference oleyl alcohol (OA) is selected. The simplified approach using synthetic broth is sufficient for the investigation of extraction capacity of ILs and their selection. The obtained screening results show the importance of the balance between polar and non-polar forces in the solvent structure/ IL structure. Using a real fermentation broth the selected IL 1-decyl-3-methylimidazolium tetracyanoborate showed under all tested process conditions a better performance than the reference solvent OA because it can recover also the valuable side-product acetone.

The lack of available physico-chemical data on ILs makes detailed computer-aided modelling challenging. Therefore a model of phase equilibria is developed and used to obtain a conceptual process design of the extraction based process.