The Experts below are selected from a list of 2418 Experts worldwide ranked by ideXlab platform
Jianlong Wang - One of the best experts on this subject based on the ideXlab platform.
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Predictive functional profiling of microbial communities in Fermentative Hydrogen Production system using PICRUSt
International Journal of Hydrogen Energy, 2021Co-Authors: Yanan Yin, Jianlong WangAbstract:Abstract PICRUSt (phylogenetic investigation of communities by reconstruction of unobserved states) is based on 16S rRNA sequencing data, which can analyze the microbial functions in fermentation system. In this study, PICRUSt was adopted to figure out the direct evidence of functions of the microbial community in bioHydrogen Production system. PICRUSt analysis demonstrated that metabolic flux shifted from acid-producing pathway to Hydrogen-producing pathway, and the Hydrogen-consuming homoacetogenic pathway was eliminated by ionizing radiation pretreatment at 5 kGy. KEGG (Kyoto Encyclopedia of Genes and Genomes) based functional genes analysis showed enriched energy metabolism and diminished homoaceto gene, which enhanced the Hydrogen Production. However, the diminished carbohydrate metabolism indicated that the pretreatment reduced the activity of microbial consortia to degrade various substrates. This study suggested that PICRUSt is an effective approach to analyze the functional profiling of microbial community in Fermentative Hydrogen Production system.
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Comparison of Fermentative Hydrogen Production from glycerol using immobilized and suspended mixed cultures
International Journal of Hydrogen Energy, 2021Co-Authors: Yang Chen, Yanan Yin, Jianlong WangAbstract:Abstract This study explored the Fermentative Hydrogen Production by immobilized microorganisms from glycerol, which is the byproduct of biodiesel Production, and compared it with suspended fermentation. The effect of immobilization on Hydrogen Production process was examined. Results showed that both cumulative Hydrogen Production (CHP) and Hydrogen yield (HY) were enhanced by microbial immobilization. The highest CHP and HY of 64 mL/100 mL and 0.52 mol H2/mol glycerol were obtained by immobilized microorganisms, compared to 9 mL/100 mL and 0.29 mol H2/mol glycerol in suspended microorganisms. Immobilization enhanced CHP and HY by 611.1% and 79.3%. In addition, immobilized microorganisms showed stronger tolerance to high substrate concentration and higher capability in glycerol utilization, which is of great significance for Hydrogen Production from glycerol. The enhanced Hydrogen Production may be due to the favorable micro-environment for different microorganisms in immobilized beads.
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Recent advance in inhibition of dark Fermentative Hydrogen Production
International Journal of Hydrogen Energy, 2021Co-Authors: Yang Chen, Yanan Yin, Jianlong WangAbstract:Abstract Dark Fermentative Hydrogen Production is an effective and feasible technology for biological Hydrogen Production. However, this technology has not been commercially applied yet. One of the major reasons is that several inhibitory factors limit Hydrogen Production and the commercial potential. In this review paper, the various inhibitory factors which influence the dark fermentation Hydrogen Production were systematically analyzed and summarized, including inorganic inhibitors (heavy metal ions, light metal ions, ammonia, sulfate and Hydrogen gas), organic inhibitors (volatile fatty acids, furan derivative and phenolic components), and bio-inhibitors (bacteriocins and thiosulfinate). The inhibitory concentration and mechanism were discussed in-depth and comprehensively. The strategies for mitigating these inhibitory factors were also introduced and discussed. Suggestion for future study in this aspect was proposed to promote the scale-up and commercial application of dark Fermentative Hydrogen Production.
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microbial community diversity during Fermentative Hydrogen Production inoculating various pretreated cultures
International Journal of Hydrogen Energy, 2019Co-Authors: Guang Yang, Yanan Yin, Jianlong WangAbstract:Abstract This study adopted five pretreatment means (base, aeration, γ-radiation, acid and heat-shock) for enriching Hydrogen-producing bacteria from anaerobically digested sludge, aiming to investigate the microbial community diversity during Fermentative Hydrogen Production using various pretreatments as inoculum. The experimental results indicated that all five pretreatments could effectively enrich Hydrogen-producing bacteria from the seed sludge, while the microbial communities showed a great difference among various pretreated groups. The most three dominant genera were Paraclostridium (28.6%), Clostridium sensu stricto 1 (19.8%) and Terrisporobacter (19.4%) for base pretreated group, Enterococcus (67.2%), Clostridium sensu stricto 1 (10%) and Citrobacter (5.6%) for aeration pretreated group, Clostridium sensu stricto 1 (63.9%), Paeniclostridium (9.3%) and Romboutsia (7%) for γ-radiation pretreated group, Clostridium sensu stricto 1 (51.9%), Romboutsia (22.4%) and Paeniclostridium (8.2%) for acid pretreated group, and Paraclostridium (61.2%), Exiguobacterium (23.1%) and Clostridium sensu stricto 1 (8.1%) for heat-shock pretreated group, respectively. Different microbial communities resulted in diverse process performance and metabolic pathway. Heat-shock pretreatment achieved the maximum Hydrogen yield of 1.58 mol/mol-glucose and maximum Hydrogen Production rate of 37.65 mL/h. The dominance of genus Paraclostridium was supposed to be responsible for the highest Hydrogen Production.
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Fermentative Hydrogen Production from macroalgae laminaria japonica pretreated by microwave irradiation
International Journal of Hydrogen Energy, 2019Co-Authors: Yanan Yin, Jianlong WangAbstract:Abstract Pretreatment is an essential procedure to enhance the biodegradability when algae biomass is used as substrate for Fermentative Hydrogen Production, In this study the potential of microwave pretreatment for enhancing the Hydrogen Production from macroalgae biomass Laminaria japonica was investigated. Microwave pretreatment at different temperatures (100–180 °C, 30 min) was explored, algae biomass disruption increased with increasing temperature, while highest Hydrogen yield of 15.8 mL/g TSadded was obtained from 160 °C microwave treated algae biomass. Hydrogen Production can be indicated by the deHydrogenase activity. After the microwave treatment, Hydrogen Production process altered from butyrate-type to acetate-type fermentation. Maximum Hydrogen yield was enhanced by 1.9 fold compared with the control test. Indicating microwave treatment can be a good candidate in enhancing the Hydrogen Production from macroalgae biomass.
Nanqi Ren - One of the best experts on this subject based on the ideXlab platform.
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Enhanced photo-Fermentative Hydrogen Production of Rhodopseudomonas sp. nov. strain A7 by biofilm reactor
International Journal of Hydrogen Energy, 2017Co-Authors: Han-quan Wen, Nanqi Ren, Du Jian, Defeng Xing, Jie Ding, Bing-feng LiuAbstract:Abstract To achieve stable and efficient photo-Fermentative Hydrogen Production, this work investigated photo-Fermentative Hydrogen Production by forming biofilm on the surface of carrier in the biofilm reactor (BR). Results showed the Hydrogen Production performance was greatly improved by formed biofilm. The time of Hydrogen Production and efficiency of substrate utilization were enhanced obviously compared to the control reactor (CR). When the CR was used, Hydrogen Production stopped at 7th day and maximum cumulative Hydrogen volume and Hydrogen yield were 1730 ± 87 mL/L and 1.44 ± 0.07 mol H 2 /mol acetate, respectively. However, in the BR Hydrogen Production volume of 3028 ± 150 mL/L and Hydrogen yield of 2.52 ± 0.13 mol H 2 /mol acetate were obtained, which were enhanced about 75% compared to that of the CR. The time of Hydrogen Production extended from 7 days of CR to 12 days of BR and the substrate conversion efficiency increased from 36% of CR to 63% of BR. It was worth noting at 8th day that substrate was almost utilized completely but Hydrogen Production still lasted for 4 days. This suggested that the formation of biofilm in BR was favorable to continuous Hydrogen Production and substrate utilization with high efficiency. Results demonstrated the BR can get a more stable and consistent operating process and it was a proper and potential way to produce Hydrogen by photo-Fermentative bacteria (PFB).
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Enhanced photo-Fermentative Hydrogen Production of Rhodopseudomonas sp. nov. strain A7 by the addition of TiO2, ZnO and SiC nanoparticles
International Journal of Hydrogen Energy, 2017Co-Authors: Bing-feng Liu, Defeng Xing, Jie Ding, Yaruo Jin, Zhijiang Wang, Nanqi RenAbstract:Abstract In order to strengthen photo-Fermentative Hydrogen Production by different photocatalytic nanoparticles, Hydrogen Production by photo-Fermentative bacteria with addition of TiO 2 , ZnO and SiC nanoparticles in batch culture were investigated in this study. The results indicated that three nanoparticles could improve Hydrogen Production performance of Rhodopseudomonas sp. nov. strain A7 under respective optimal conditions. The Hydrogen yield of 2.81 mol-H 2 /mol-acetate was obtained when TiO 2 nanoparticles with a concentration of 300 mg/L and size of 25 nm. The concentration of ZnO nanoparticles was at 100 mg/L, Hydrogen yield reached 2.64 mol-H 2 /mol-acetate. Compared with TiO 2 and ZnO nanoparticles, SiC nanoparticles exhibited greatest potential for enhancing photo-Hydrogen Production. By addition of nano-SiC with concentration of 200 mg/L which was prepared at temperature of 1500 °C, the maximum Hydrogen volume, average Hydrogen content and Hydrogen yield of strain A7 were achieved at 2272 mL-H 2 /L-culture, 85.2% and 2.99 mol-H 2 /mol-acetate, respectively. And Hydrogen Production was 18.6% higher than that of alone strain A7 without the addition of nanoparticles. Therefore, the addition of SiC nanoparticles is a promising strategy to improve photo-Fermentative Hydrogen Production from wastewater.
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Fermentative Hydrogen Production using wheat flour hydrolysate by mixed culture
International Journal of Hydrogen Energy, 2015Co-Authors: Wei Han, Xiaonan Wang, Jingang Huang, Junhong Tang, Nanqi RenAbstract:Abstract Wheat bran was first used to produce glucoamylase by Aspergillus awamori from solid-state fermentation (SSF). Wheat flour with different mass ratios of 2%–8% (w/v) were hydrolyzed by glucoamylase to generate the wheat flour hydrolysates (containing glucose concentrations of 10.69–35.14 g/L) which were then utilized as substrate for Fermentative Hydrogen Production by heat pretreated sludge. The cumulative Hydrogen Production increased from 1181.3 ml to 2379.6 ml as glucose concentration increased from 10.69 g/L to 35.14 g/L. The modified Gompertz model was used to describe the cumulative Hydrogen Production for different glucose concentrations. However, the maximum Hydrogen yield of 1.9 mol H 2 /mol glucose was observed at glucose concentration of 10.69 g/L probably due to the products inhibition and oxidization/reduction of NADH. The wheat flour hydrolysate could be used to replace commercial glucose for Fermentative Hydrogen Production and therefore reduce the cost of Hydrogen Production for large scale.
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Fermentative Hydrogen Production from molasses wastewater in a continuous mixed immobilized sludge reactor.
Bioresource technology, 2012Co-Authors: Wei Han, Bing Wang, Yan Zhou, De-xin Wang, Yan Wang, Li-ran Yue, Nanqi RenAbstract:A novel continuous mixed immobilized sludge reactor (CMISR) containing activated carbon as support carrier was used for Fermentative Hydrogen Production from molasses wastewater. When the CMISR system operated at the conditions of influent COD of 2000-6000mg/L, hydraulic retention time (HRT) of 6h and temperature of 35°C, stable ethanol type fermentation was formed after 40days operation. The H(2) content in biogas and chemical oxygen demand (COD) removal were estimated to be 46.6% and 13%, respectively. The effects of organic loading rates (OLRs) on the CMISR Hydrogen Production system were also investigated. It was found that the maximum Hydrogen Production rate of 12.51mmol/hL was obtained at OLR of 32kg/m(3)d and the maximum Hydrogen yield by substrate consumed of 130.57mmol/mol happened at OLR of 16kg/m(3)d. Therefore, the continuous mixed immobilized sludge reactor (CMISR) could be a promising immobilized system for Fermentative Hydrogen Production.
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Effect of L-cysteine on Continuous Fermentative Hydrogen Production
Applied Mechanics and Materials, 2012Co-Authors: Wan Qian Guo, Jie Ding, Nanqi RenAbstract:Two continuously stirred tank reactors (CSTR) were used to investigate the effect of L-cysteine on continuous dark Fermentative Hydrogen Production system. L-cysteine was added into one of the reactors at 0.1 g/L continuously, the other reactor was without L-cysteine addition. Liquid end products, oxidation-reduction potential (ORP), pH, biomass and Hydrogen Production rate (HPR) were examined during the operation. The lag time of ethanol generation in the L-cysteine added reactor was shortened to 21 days compared to 25 days in the blank. The HPR increased from 2.73 L/d in the reactor without L-cysteine addition to 2.82 L/d in the added one. The volatile suspended solids (VSS) in the reactor with L-cyateine was 10.1 g/L by the end of the operation compared to 9.2 g/L in the other. Addition of L-cysteine into the Hydrogen Production system accelerates the formation of ethanol-type fermentation and enhances the Hydrogen Production by creating an optimal low ORP environment, and by increasing the biomass growth simultaneously.
Bing-feng Liu - One of the best experts on this subject based on the ideXlab platform.
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Enhanced photo-Fermentative Hydrogen Production of Rhodopseudomonas sp. nov. strain A7 by biofilm reactor
International Journal of Hydrogen Energy, 2017Co-Authors: Han-quan Wen, Nanqi Ren, Du Jian, Defeng Xing, Jie Ding, Bing-feng LiuAbstract:Abstract To achieve stable and efficient photo-Fermentative Hydrogen Production, this work investigated photo-Fermentative Hydrogen Production by forming biofilm on the surface of carrier in the biofilm reactor (BR). Results showed the Hydrogen Production performance was greatly improved by formed biofilm. The time of Hydrogen Production and efficiency of substrate utilization were enhanced obviously compared to the control reactor (CR). When the CR was used, Hydrogen Production stopped at 7th day and maximum cumulative Hydrogen volume and Hydrogen yield were 1730 ± 87 mL/L and 1.44 ± 0.07 mol H 2 /mol acetate, respectively. However, in the BR Hydrogen Production volume of 3028 ± 150 mL/L and Hydrogen yield of 2.52 ± 0.13 mol H 2 /mol acetate were obtained, which were enhanced about 75% compared to that of the CR. The time of Hydrogen Production extended from 7 days of CR to 12 days of BR and the substrate conversion efficiency increased from 36% of CR to 63% of BR. It was worth noting at 8th day that substrate was almost utilized completely but Hydrogen Production still lasted for 4 days. This suggested that the formation of biofilm in BR was favorable to continuous Hydrogen Production and substrate utilization with high efficiency. Results demonstrated the BR can get a more stable and consistent operating process and it was a proper and potential way to produce Hydrogen by photo-Fermentative bacteria (PFB).
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Enhanced photo-Fermentative Hydrogen Production of Rhodopseudomonas sp. nov. strain A7 by the addition of TiO2, ZnO and SiC nanoparticles
International Journal of Hydrogen Energy, 2017Co-Authors: Bing-feng Liu, Defeng Xing, Jie Ding, Yaruo Jin, Zhijiang Wang, Nanqi RenAbstract:Abstract In order to strengthen photo-Fermentative Hydrogen Production by different photocatalytic nanoparticles, Hydrogen Production by photo-Fermentative bacteria with addition of TiO 2 , ZnO and SiC nanoparticles in batch culture were investigated in this study. The results indicated that three nanoparticles could improve Hydrogen Production performance of Rhodopseudomonas sp. nov. strain A7 under respective optimal conditions. The Hydrogen yield of 2.81 mol-H 2 /mol-acetate was obtained when TiO 2 nanoparticles with a concentration of 300 mg/L and size of 25 nm. The concentration of ZnO nanoparticles was at 100 mg/L, Hydrogen yield reached 2.64 mol-H 2 /mol-acetate. Compared with TiO 2 and ZnO nanoparticles, SiC nanoparticles exhibited greatest potential for enhancing photo-Hydrogen Production. By addition of nano-SiC with concentration of 200 mg/L which was prepared at temperature of 1500 °C, the maximum Hydrogen volume, average Hydrogen content and Hydrogen yield of strain A7 were achieved at 2272 mL-H 2 /L-culture, 85.2% and 2.99 mol-H 2 /mol-acetate, respectively. And Hydrogen Production was 18.6% higher than that of alone strain A7 without the addition of nanoparticles. Therefore, the addition of SiC nanoparticles is a promising strategy to improve photo-Fermentative Hydrogen Production from wastewater.
Yanan Yin - One of the best experts on this subject based on the ideXlab platform.
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Recent advance in inhibition of dark Fermentative Hydrogen Production
International Journal of Hydrogen Energy, 2021Co-Authors: Yang Chen, Yanan Yin, Jianlong WangAbstract:Abstract Dark Fermentative Hydrogen Production is an effective and feasible technology for biological Hydrogen Production. However, this technology has not been commercially applied yet. One of the major reasons is that several inhibitory factors limit Hydrogen Production and the commercial potential. In this review paper, the various inhibitory factors which influence the dark fermentation Hydrogen Production were systematically analyzed and summarized, including inorganic inhibitors (heavy metal ions, light metal ions, ammonia, sulfate and Hydrogen gas), organic inhibitors (volatile fatty acids, furan derivative and phenolic components), and bio-inhibitors (bacteriocins and thiosulfinate). The inhibitory concentration and mechanism were discussed in-depth and comprehensively. The strategies for mitigating these inhibitory factors were also introduced and discussed. Suggestion for future study in this aspect was proposed to promote the scale-up and commercial application of dark Fermentative Hydrogen Production.
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Comparison of Fermentative Hydrogen Production from glycerol using immobilized and suspended mixed cultures
International Journal of Hydrogen Energy, 2021Co-Authors: Yang Chen, Yanan Yin, Jianlong WangAbstract:Abstract This study explored the Fermentative Hydrogen Production by immobilized microorganisms from glycerol, which is the byproduct of biodiesel Production, and compared it with suspended fermentation. The effect of immobilization on Hydrogen Production process was examined. Results showed that both cumulative Hydrogen Production (CHP) and Hydrogen yield (HY) were enhanced by microbial immobilization. The highest CHP and HY of 64 mL/100 mL and 0.52 mol H2/mol glycerol were obtained by immobilized microorganisms, compared to 9 mL/100 mL and 0.29 mol H2/mol glycerol in suspended microorganisms. Immobilization enhanced CHP and HY by 611.1% and 79.3%. In addition, immobilized microorganisms showed stronger tolerance to high substrate concentration and higher capability in glycerol utilization, which is of great significance for Hydrogen Production from glycerol. The enhanced Hydrogen Production may be due to the favorable micro-environment for different microorganisms in immobilized beads.
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Predictive functional profiling of microbial communities in Fermentative Hydrogen Production system using PICRUSt
International Journal of Hydrogen Energy, 2021Co-Authors: Yanan Yin, Jianlong WangAbstract:Abstract PICRUSt (phylogenetic investigation of communities by reconstruction of unobserved states) is based on 16S rRNA sequencing data, which can analyze the microbial functions in fermentation system. In this study, PICRUSt was adopted to figure out the direct evidence of functions of the microbial community in bioHydrogen Production system. PICRUSt analysis demonstrated that metabolic flux shifted from acid-producing pathway to Hydrogen-producing pathway, and the Hydrogen-consuming homoacetogenic pathway was eliminated by ionizing radiation pretreatment at 5 kGy. KEGG (Kyoto Encyclopedia of Genes and Genomes) based functional genes analysis showed enriched energy metabolism and diminished homoaceto gene, which enhanced the Hydrogen Production. However, the diminished carbohydrate metabolism indicated that the pretreatment reduced the activity of microbial consortia to degrade various substrates. This study suggested that PICRUSt is an effective approach to analyze the functional profiling of microbial community in Fermentative Hydrogen Production system.
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microbial community diversity during Fermentative Hydrogen Production inoculating various pretreated cultures
International Journal of Hydrogen Energy, 2019Co-Authors: Guang Yang, Yanan Yin, Jianlong WangAbstract:Abstract This study adopted five pretreatment means (base, aeration, γ-radiation, acid and heat-shock) for enriching Hydrogen-producing bacteria from anaerobically digested sludge, aiming to investigate the microbial community diversity during Fermentative Hydrogen Production using various pretreatments as inoculum. The experimental results indicated that all five pretreatments could effectively enrich Hydrogen-producing bacteria from the seed sludge, while the microbial communities showed a great difference among various pretreated groups. The most three dominant genera were Paraclostridium (28.6%), Clostridium sensu stricto 1 (19.8%) and Terrisporobacter (19.4%) for base pretreated group, Enterococcus (67.2%), Clostridium sensu stricto 1 (10%) and Citrobacter (5.6%) for aeration pretreated group, Clostridium sensu stricto 1 (63.9%), Paeniclostridium (9.3%) and Romboutsia (7%) for γ-radiation pretreated group, Clostridium sensu stricto 1 (51.9%), Romboutsia (22.4%) and Paeniclostridium (8.2%) for acid pretreated group, and Paraclostridium (61.2%), Exiguobacterium (23.1%) and Clostridium sensu stricto 1 (8.1%) for heat-shock pretreated group, respectively. Different microbial communities resulted in diverse process performance and metabolic pathway. Heat-shock pretreatment achieved the maximum Hydrogen yield of 1.58 mol/mol-glucose and maximum Hydrogen Production rate of 37.65 mL/h. The dominance of genus Paraclostridium was supposed to be responsible for the highest Hydrogen Production.
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Fermentative Hydrogen Production from macroalgae laminaria japonica pretreated by microwave irradiation
International Journal of Hydrogen Energy, 2019Co-Authors: Yanan Yin, Jianlong WangAbstract:Abstract Pretreatment is an essential procedure to enhance the biodegradability when algae biomass is used as substrate for Fermentative Hydrogen Production, In this study the potential of microwave pretreatment for enhancing the Hydrogen Production from macroalgae biomass Laminaria japonica was investigated. Microwave pretreatment at different temperatures (100–180 °C, 30 min) was explored, algae biomass disruption increased with increasing temperature, while highest Hydrogen yield of 15.8 mL/g TSadded was obtained from 160 °C microwave treated algae biomass. Hydrogen Production can be indicated by the deHydrogenase activity. After the microwave treatment, Hydrogen Production process altered from butyrate-type to acetate-type fermentation. Maximum Hydrogen yield was enhanced by 1.9 fold compared with the control test. Indicating microwave treatment can be a good candidate in enhancing the Hydrogen Production from macroalgae biomass.
Gerasimos Lyberatos - One of the best experts on this subject based on the ideXlab platform.
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Modeling of Fermentative Hydrogen Production from sweet sorghum extract based on modified ADM1
International Journal of Hydrogen Energy, 2012Co-Authors: Georgia Antonopoulou, Hariklia N. Gavala, Ioannis V. Skiadas, Gerasimos LyberatosAbstract:The Anaerobic digestion model 1 (ADM1) framework can be used to predict Fermentative Hydrogen Production, since the latter is directly related to the acidogenic stage of the anaerobic digestion process. In this study, the ADM1 model framework was used to simulate and predict the process of Fermentative Hydrogen Production from the extractable sugars of sweet sorghum biomass. Kinetic parameters for sugars’ consumption and yield coefficients of acetic, propionic and butyric acid Production were estimated using the experimental data obtained from the steady states of a CSTR. Batch experiments were used for kinetic parameter validation. Since the ADM1 does not account for metabolic products such as lactic acid and ethanol that are crucial during the Fermentative Hydrogen Production process, the structure of the model was modified to include lactate and ethanol among the metabolites and to improve the predictions. The modified ADM1 simulated satisfactorily batch experiments although further modifications could be made in order to further improve the predictions for the Hydrogenogenic process.
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Effect of substrate concentration on Fermentative Hydrogen Production from sweet sorghum extract
International Journal of Hydrogen Energy, 2011Co-Authors: Georgia Antonopoulou, Hariklia N. Gavala, Ioannis V. Skiadas, Gerasimos LyberatosAbstract:Abstract The aim of the present study was to assess the influence of substrate concentration on the Fermentative Hydrogen Production from sweet sorghum extract, in a continuous stirred tank bioreactor. The reactor was operated at a Hydraulic Retention Time (HRT) of 12 h and carbohydrate concentrations ranging from 9.89 to 20.99 g/L, in glucose equivalents. The maximum Hydrogen Production rate and yield were obtained at the concentration of 17.50 g carbohydrates/L and were 2.93 ± 0.09 L H 2 /L reactor/d and 0.74 ± 0.02 mol H 2 /mol glucose consumed, corresponding to 8.81 ± 0.02 L H 2 /kg sweet sorghum, respectively. The main metabolic product at all steady states was butyric acid, while ethanol Production was high at high substrate concentrations. The experiments showed that Hydrogen productivity depends significantly on the initial carbohydrate concentration, which also influences the distribution of the metabolic products.
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Influence of pH on Fermentative Hydrogen Production from sweet sorghum extract
International Journal of Hydrogen Energy, 2010Co-Authors: Georgia Antonopoulou, Hariklia N. Gavala, Ioannis V. Skiadas, Gerasimos LyberatosAbstract:Abstract The present study focused on the influence of pH on the Fermentative Hydrogen Production from the sugars of sweet sorghum extract, in a continuous stirred tank bioreactor. The reactor was operated at a Hydraulic Retention Time of 12 h and a pH range of 3.5–6.5. The maximum Hydrogen Production rate and yield were obtained at pH 5.3 and were 1752 ± 54 mL H 2 /d or 3.50 ± 0.07 L H 2 /L reactor/d and 0.93 ± 0.03 mol H 2 /mol glucose consumed or 10.51 L H 2 /kg sweet sorghum, respectively. The main metabolic product at this pH value was butyric acid. The Hydrogen productivity and yield were still at high levels for the pH range of 5.3–4.7, suggesting a pH value of 4.7 as optimum for Hydrogen Production from an economical point of view, since the energy demand for chemicals is lower at this pH. At this pH range, the dominant fermentation product was butyric acid but when the pH culture sharply decreased to 3.5, Hydrogen evolution ceased and the dominant metabolic products were lactic acid and ethanol.