TY - JOUR
T1 - Extractive fermentation with non-ionic surfactants to enhance butanol production
AU - Dhamole, Pradip B.
AU - Wang, Zhilong
AU - Liu, Yuanqin
AU - Wang, Bin
AU - Feng, Hao
N1 - Funding Information:
The project was funded by Energy Biosciences Institute grant No. 555794-231000 . We are grateful to Mr. John Jerrell for his assistance in GC analysis.
Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2012/5
Y1 - 2012/5
N2 - One of the major limitations in butanol fermentation is the end product toxicity which limits the butanol yield and increases the downstream processing costs. In this work, a range of non-ionic surfactants (Triton X 114, L64, L62LF, L61, and L62) was tested to enhance the acetone-butanol (AB) production, and to extract and separate butanol from the fermentation broth. In biocompatibility tests, a volume fraction of 3% L62, L62LF, and L61 did not show inhibition to AB production in 72-h fermentation using Clostridium pasteurianum. Three-percent L64 reduced the AB yield whereas Triton X 114 (3%) inhibited the AB production. Further optimization with L62 at 6% resulted in a butanol yield of 225% higher than the control. The partition coefficient of butanol in L62-water two phase systems in cloud point extraction ranged from 3 to 4. A considerable enrichment of butanol (6 times) was achieved in the surfactant-rich phase over the control. In addition, the downstream process volume was reduced by 4-6 times. Butanol was separated from the surfactant-rich phase (obtained from model system) by evaporation between 120 and 130 °C. The butanol was enriched in the condensate reaching a concentration of 106.8 g l -1, under which butanol automatically separated into two phases. The L62 was recovered by evaporation and reused for 3 times without affecting the partition coefficient, volume reduction, and butanol recovery in the surfactant-rich phase. The results demonstrated that the L62 not only significantly enhanced the butanol production but also functioned as a good extractant for separating butanol from the fermentation broth.
AB - One of the major limitations in butanol fermentation is the end product toxicity which limits the butanol yield and increases the downstream processing costs. In this work, a range of non-ionic surfactants (Triton X 114, L64, L62LF, L61, and L62) was tested to enhance the acetone-butanol (AB) production, and to extract and separate butanol from the fermentation broth. In biocompatibility tests, a volume fraction of 3% L62, L62LF, and L61 did not show inhibition to AB production in 72-h fermentation using Clostridium pasteurianum. Three-percent L64 reduced the AB yield whereas Triton X 114 (3%) inhibited the AB production. Further optimization with L62 at 6% resulted in a butanol yield of 225% higher than the control. The partition coefficient of butanol in L62-water two phase systems in cloud point extraction ranged from 3 to 4. A considerable enrichment of butanol (6 times) was achieved in the surfactant-rich phase over the control. In addition, the downstream process volume was reduced by 4-6 times. Butanol was separated from the surfactant-rich phase (obtained from model system) by evaporation between 120 and 130 °C. The butanol was enriched in the condensate reaching a concentration of 106.8 g l -1, under which butanol automatically separated into two phases. The L62 was recovered by evaporation and reused for 3 times without affecting the partition coefficient, volume reduction, and butanol recovery in the surfactant-rich phase. The results demonstrated that the L62 not only significantly enhanced the butanol production but also functioned as a good extractant for separating butanol from the fermentation broth.
KW - Biocompatibility
KW - Biofuel
KW - Butanol
KW - Extractive fermentation
KW - Non-ionic surfactant
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U2 - 10.1016/j.biombioe.2012.02.007
DO - 10.1016/j.biombioe.2012.02.007
M3 - Article
AN - SCOPUS:84862783844
SN - 0961-9534
VL - 40
SP - 112
EP - 119
JO - Biomass and Bioenergy
JF - Biomass and Bioenergy
ER -