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Simultaneous hydrogen and ethanol production from cascade utilization of mono-substrate in integrated dark and photo-fermentative reactor.

Liu BF, Xie GJ, Wang RQ, Xing DF, Ding J, Zhou X, Ren HY, Ma C, Ren NQ - Biotechnol Biofuels (2015)

Bottom Line: Moreover, simultaneous hydrogen and ethanol production were achieved by coupling E. harbinese B49 and R. faecalis RLD-53 in the IDPFR.According to stoichiometry, the hydrogen and ethanol production efficiencies were 82.67% and 82.19%, respectively.Therefore, IDPFR was an effective strategy for coupling DFB and PFB to fulfill efficient energy recovery from waste biomass.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090 China.

ABSTRACT

Background: Integrating hydrogen-producing bacteria with complementary capabilities, dark-fermentative bacteria (DFB) and photo-fermentative bacteria (PFB), is a promising way to completely recover bioenergy from waste biomass. However, the current coupled models always suffer from complicated pretreatment of the effluent from dark-fermentation or imbalance between dark and photo-fermentation, respectively. In this work, an integrated dark and photo-fermentative reactor (IDPFR) was developed to completely convert an organic substrate into bioenergy.

Results: In the IDPFR, Ethanoligenens harbinese B49 and Rhodopseudomonas faecalis RLD-53 were separated by a membrane into dark and photo chambers, while the acetate produced by E. harbinese B49 in the dark chamber could freely pass through the membrane into the photo chamber and serve as a carbon source for R. faecalis RLD-53. The hydrogen yield increased with increasing working volume of the photo chamber, and reached 3.38 mol H2/mol glucose at the dark-to-photo chamber ratio of 1:4. Hydrogen production by the IDPFR was also significantly affected by phosphate buffer concentration, glucose concentration, and ratio of dark-photo bacteria. The maximum hydrogen yield (4.96 mol H2/mol glucose) was obtained at a phosphate buffer concentration of 20 mmol/L, a glucose concentration of 8 g/L, and a ratio of dark to photo bacteria of 1:20. As the glucose and acetate were used up by E. harbinese B49 and R. faecalis RLD-53, ethanol produced by E. harbinese B49 was the sole end-product in the effluent from the IDPFR, and the ethanol concentration was 36.53 mmol/L with an ethanol yield of 0.82 mol ethanol/mol glucose.

Conclusions: The results indicated that the IDPFR not only circumvented complex pretreatments on the effluent in the two-stage process, but also overcame the imbalance of growth and metabolic rate between DFB and PFB in the co-culture process, and effectively enhanced cooperation between E. harbinense B49 and R. faecalis RLD-53. Moreover, simultaneous hydrogen and ethanol production were achieved by coupling E. harbinese B49 and R. faecalis RLD-53 in the IDPFR. According to stoichiometry, the hydrogen and ethanol production efficiencies were 82.67% and 82.19%, respectively. Therefore, IDPFR was an effective strategy for coupling DFB and PFB to fulfill efficient energy recovery from waste biomass.

No MeSH data available.


Related in: MedlinePlus

Hydrogen production, glucose consumption, and acetate accumulation in IDPFR at different working volume ratios of dark chamber to photo chamber. (a) 1:2; (b) 1:3; (c) 1:4; (d) 1:5.
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Fig2: Hydrogen production, glucose consumption, and acetate accumulation in IDPFR at different working volume ratios of dark chamber to photo chamber. (a) 1:2; (b) 1:3; (c) 1:4; (d) 1:5.

Mentions: The hydrogen production volume increased with dark-to-photo chamber ratio from 1:2 to 1:4, and decreased with a ratio from 1:4 to 1:5 (Figure 2). At a working volume ratio of 1:2, hydrogen production by the dark chamber was 1,791.67 ml/L, while hydrogen production by the photo chamber was only 1,138.97 ml/L. The total hydrogen production was 2,930.63 ml/L with a hydrogen yield of 2.35 mol H2/mol glucose. With an increase of photo chamber working volume, more R. faecalis RLD-53 could use the end product from E. harbinense B49 for hydrogen production, while E. harbinense B49 was restricted in the small dark chamber. Acetic acid produced by E. harbinense B49 was not accumulated but converted into hydrogen by R. faecalis RLD-53. Consequently, hydrogen production by photo chamber increased significantly. At a working volume ratio of 1:4, hydrogen production by the dark and photo chambers reached maximum simultaneously at 1,991.67 and 2,225.15 ml/L, with a hydrogen yield of 3.38 mol H2/mol glucose. However, with a further decrease of the working volume ratio to 1:5, total hydrogen production decreased sharply to 3,269.29 ml/L with a hydrogen yield of 2.63 mol H2/mol glucose.Figure 2


Simultaneous hydrogen and ethanol production from cascade utilization of mono-substrate in integrated dark and photo-fermentative reactor.

Liu BF, Xie GJ, Wang RQ, Xing DF, Ding J, Zhou X, Ren HY, Ma C, Ren NQ - Biotechnol Biofuels (2015)

Hydrogen production, glucose consumption, and acetate accumulation in IDPFR at different working volume ratios of dark chamber to photo chamber. (a) 1:2; (b) 1:3; (c) 1:4; (d) 1:5.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4308915&req=5

Fig2: Hydrogen production, glucose consumption, and acetate accumulation in IDPFR at different working volume ratios of dark chamber to photo chamber. (a) 1:2; (b) 1:3; (c) 1:4; (d) 1:5.
Mentions: The hydrogen production volume increased with dark-to-photo chamber ratio from 1:2 to 1:4, and decreased with a ratio from 1:4 to 1:5 (Figure 2). At a working volume ratio of 1:2, hydrogen production by the dark chamber was 1,791.67 ml/L, while hydrogen production by the photo chamber was only 1,138.97 ml/L. The total hydrogen production was 2,930.63 ml/L with a hydrogen yield of 2.35 mol H2/mol glucose. With an increase of photo chamber working volume, more R. faecalis RLD-53 could use the end product from E. harbinense B49 for hydrogen production, while E. harbinense B49 was restricted in the small dark chamber. Acetic acid produced by E. harbinense B49 was not accumulated but converted into hydrogen by R. faecalis RLD-53. Consequently, hydrogen production by photo chamber increased significantly. At a working volume ratio of 1:4, hydrogen production by the dark and photo chambers reached maximum simultaneously at 1,991.67 and 2,225.15 ml/L, with a hydrogen yield of 3.38 mol H2/mol glucose. However, with a further decrease of the working volume ratio to 1:5, total hydrogen production decreased sharply to 3,269.29 ml/L with a hydrogen yield of 2.63 mol H2/mol glucose.Figure 2

Bottom Line: Moreover, simultaneous hydrogen and ethanol production were achieved by coupling E. harbinese B49 and R. faecalis RLD-53 in the IDPFR.According to stoichiometry, the hydrogen and ethanol production efficiencies were 82.67% and 82.19%, respectively.Therefore, IDPFR was an effective strategy for coupling DFB and PFB to fulfill efficient energy recovery from waste biomass.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090 China.

ABSTRACT

Background: Integrating hydrogen-producing bacteria with complementary capabilities, dark-fermentative bacteria (DFB) and photo-fermentative bacteria (PFB), is a promising way to completely recover bioenergy from waste biomass. However, the current coupled models always suffer from complicated pretreatment of the effluent from dark-fermentation or imbalance between dark and photo-fermentation, respectively. In this work, an integrated dark and photo-fermentative reactor (IDPFR) was developed to completely convert an organic substrate into bioenergy.

Results: In the IDPFR, Ethanoligenens harbinese B49 and Rhodopseudomonas faecalis RLD-53 were separated by a membrane into dark and photo chambers, while the acetate produced by E. harbinese B49 in the dark chamber could freely pass through the membrane into the photo chamber and serve as a carbon source for R. faecalis RLD-53. The hydrogen yield increased with increasing working volume of the photo chamber, and reached 3.38 mol H2/mol glucose at the dark-to-photo chamber ratio of 1:4. Hydrogen production by the IDPFR was also significantly affected by phosphate buffer concentration, glucose concentration, and ratio of dark-photo bacteria. The maximum hydrogen yield (4.96 mol H2/mol glucose) was obtained at a phosphate buffer concentration of 20 mmol/L, a glucose concentration of 8 g/L, and a ratio of dark to photo bacteria of 1:20. As the glucose and acetate were used up by E. harbinese B49 and R. faecalis RLD-53, ethanol produced by E. harbinese B49 was the sole end-product in the effluent from the IDPFR, and the ethanol concentration was 36.53 mmol/L with an ethanol yield of 0.82 mol ethanol/mol glucose.

Conclusions: The results indicated that the IDPFR not only circumvented complex pretreatments on the effluent in the two-stage process, but also overcame the imbalance of growth and metabolic rate between DFB and PFB in the co-culture process, and effectively enhanced cooperation between E. harbinense B49 and R. faecalis RLD-53. Moreover, simultaneous hydrogen and ethanol production were achieved by coupling E. harbinese B49 and R. faecalis RLD-53 in the IDPFR. According to stoichiometry, the hydrogen and ethanol production efficiencies were 82.67% and 82.19%, respectively. Therefore, IDPFR was an effective strategy for coupling DFB and PFB to fulfill efficient energy recovery from waste biomass.

No MeSH data available.


Related in: MedlinePlus