Process design of extraction of bioproducts with ionic liquids Martin
Transcription
Process design of extraction of bioproducts with ionic liquids Martin
Process design of extraction of bioproducts with ionic liquids Martin Stoffers, Andrzej Górak Martin Stoffers project started 01.06.09 Laboratory of Fluid Separations Separations, Department of Biochemical and Chemical Engineering, TU Dortmund [email protected] Introduction Acetone-Butanol-Ethanol-(ABE)-fermentation is getting more and more interesting for the production of alcohols, but efficient purification technology of fermentation broth is still a bottleneck. M i drawbacks: Main d b k toxicity i i off butanol b l towards d the h microorganisms i i resulting l i in i a limited li i d productivity d i i high purification costs due to energy-intensive distillation step Extraction with ionic liquids (ILs) for bioalcohol recovery is an interesting but very challenging option: Possibility of in-situ liquid-liquid-extraction in order to avoid product inhibition Commonly used organic extraction solvents are often flammable, hazardous or toxic Objectives: Design of a downstream processing method for biobutanol recovery from fermentation broth while certain class of ionic liquids is used as extraction solvent Experimental investigation of the extraction step in lab lab-scale scale Modelling and simulation of the extraction step and investigation of different process concepts Results Experimental setup Liquid-liquid extraction experiments are conducted in agitated and tempered glass vessels. Distribution coefficient ffi i and d selectivity l i i are indicators i di f for the quality of the butanol extraction. These data are useful for the modelling of the extraction process Mass fraction : wi = mi m tot IL,eq Di = Distribution coefficient : wi aq,eq wi IL Selectivity : Si, j = Di Dj wi aq = wi IL-phase IL wj aq wj aqueous phase with components : i, j ionic liquid, aqueous phases : IL, aq Analytics The h aqueous phase h is analysed l d by b High h Performance f Liquid d Chromatography (HPLC). The ionic liquid phase is analysed by Karl-Fischer titration. The calculation of the distribution coefficient and selectivity is made with the help of HPLC-, KarlFischer results and weighted samples. 0,008 Butanol Butyric acid Acetone Acetic acid 0,006 wiaq,eq [-] Investigation of extraction time I former In f studies di extraction i time i was set to 24 h to ensure that h phase h equilibrium is reached. Concentrations between 0 and 120 min extraction time are analysed. No significant change in four concentrations in the first hour could be observed. Thus, extraction time is reduced from 24 to 1 h 0,004 0,002 0 0 Acknowledgements The support of Merck KGaA is highly acknowledged. CLIB-Graduate Cluster Industrial Biotechnology: Project Presentation. 30 60 90 Extraction E t ti time ti [min] [ i ] 120