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Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid
Published on: November 15, 2017
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Acetone-butanol-ethanol production in a novel continuous flow system
Elsayed Elbeshbishy1, Bipro Ranjan Dhar1, Hisham Hafez2
1University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Bioresource Technology
|May 13, 2015
Summary
This study demonstrates a novel biohydrogen reactor clarifier system for continuous acetone-butanol-ethanol (ABE) production. Recycling settled biomass achieved high concentrations, leading to sustainable ABE fermentation.
Area of Science:
- Biotechnology
- Biochemical Engineering
- Environmental Science
Background:
- Acetone-butanol-ethanol (ABE) fermentation is a crucial biofuel production process.
- Maintaining high biomass concentration is essential for efficient continuous fermentation.
- Integrated systems offer potential for process intensification.
Purpose of the Study:
- To evaluate a novel integrated biohydrogen reactor clarifier system (IBRCS) for continuous ABE production.
- To assess the impact of varying organic loading rates (OLRs) on ABE yield and productivity.
- To determine the feasibility of biomass recycling for sustained fermentation.
Main Methods:
- Utilized a mixed microbial culture in a continuous reactor system.
- Implemented an integrated biohydrogen reactor clarifier system (IBRCS) with biomass recycling.
- Operated the system at different organic loading rates (OLRs): 21, 64, and 128 gCOD/L/day.
Main Results:
- Achieved average ABE concentrations of 2.3, 7.0, and 14.6 gABE/L at the tested OLRs.
- Attained ABE production rates of 0.4, 1.4, and 2.8 gABE/L/h, respectively.
- Identified acetic, propionic, and butyric acids as major volatile fatty acids in the effluent, with shifts in predominance at higher OLRs.
Conclusions:
- The IBRCS with biomass recycling is a practical approach for achieving high biomass concentration and sustainable continuous ABE fermentation.
- Increasing OLR significantly enhanced ABE production rates and concentrations.
- The system demonstrates potential for efficient biofuel production from organic waste streams.
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