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Published on: August 9, 2024
Extractive acetonobutylic fermentation by coupling ultrafiltration and distillation
M Minier1, R Grateloup, E Blanc-Ferras
1Département de Génie Biochimique et Alimentaire, UA-CNRS-No. 544, Institut National des Sciences Appliquées-C.T.B.M., Avenue de Rangueil, F-31077 Toulouse Cedex, France.
Biotechnology and Bioengineering
|April 15, 1990
Summary
This study optimized an extractive acetonobutylic fermentation process using integrated bioproduction, ultrafiltration, and distillation. The enhanced method significantly boosted solvent production and productivity while minimizing medium replacement.
Area of Science:
- Biotechnology
- Chemical Engineering
- Fermentation Technology
Background:
- Acetone-butanol-ethanol (ABE) solvent production via fermentation is often limited by product inhibition and low solvent titers.
- Traditional ABE fermentation processes struggle with efficient product recovery and continuous operation.
Purpose of the Study:
- To develop and optimize an integrated extractive fermentation process for enhanced ABE solvent production.
- To investigate the role of extracellular autolytic enzymes and optimize distillation parameters to improve process efficiency.
Main Methods:
- Integration of bioproduction with Ultrafiltration (UF) for biomass retention and distillation for in-situ solvent recovery.
- Performing successive batch and continuous fermentations with varying distillation temperatures and pressures.
- Analysis of extracellular autolytic enzyme activity under different fermentation conditions.
Main Results:
- The integrated process enabled simultaneous biomass retention, inhibitor removal, and solvent purification.
- Normal pressure distillation (98°C) enhanced solvent production by threefold with minimal medium exchange (dilution rate 0.002 h⁻¹).
- Optimized continuous operation with reduced distillation temperature/pressure achieved a solvent productivity of 2.6 g/L/h at a 0.036 h⁻¹ dilution rate, using 156 g/L glucose.
Conclusions:
- Extractive fermentation using UF and optimized distillation is a viable strategy for high-titer ABE solvent production.
- High-temperature distillation can negatively impact the culture medium; lower temperatures are preferable.
- The developed process offers significant improvements in solvent productivity and efficiency for industrial applications.
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