Biohydrogen Production Research Articles

Improvement of biohydrogen production from biomass using supercritical water gasification and CaO adsorption

Producing biohydrogen is a promising alternative to fossil fuels, sourced from renewable energy like wind, solar, and biomass, known for its eco-friendliness and minimal greenhouse gas emissions. This study focuses on the process design and simulation of producing biohydrogen from biomass (bagasse) gasification. New integration of the water gas shift reactor and CaO adsorption process is connected to biomass gasification with the steam/supercritical water agents for improving the hydrogen production process. Simulations show that steam gasification integrated with CaO adsorption (SG-CaO) is optimized at specific conditions, resulting in high-purity hydrogen at 99.95 %. Similarly, the supercritical water gasification integrated with CaO adsorption (SCWG-CaO) requires specific conditions, achieving exceptionally pure hydrogen at 99.99 %. In terms of energy analysis, SCWG-CaO outperforms SG-CaO, with higher hydrogen yield (14.16 % vs. 14.12 %) and greater energy efficiency (42.32 % vs. 40.26 %). It shows that the SCWG-CaO is a suitable and efficient approach for biohydrogen production, considering factors such as hydrogen purity, yield, and energy efficiency.

Biohydrogen production from DEPOME (dark fermented effluent palm oil mill effluent) via photo-fermentation utilizing indigenous bacteria

The research experimentally investigated biohydrogen production with a light intensity of 4500 lux using indigenous bacteria in DEPOME. The study was conducted in three stages: identified indigenous bacteria through next-generation sequencing (NGS) DNA, analyzed DEPOME characteristics, and produced biohydrogen. Biohydrogen production was carried out under two initial substrate pH conditions: neutral (pH 7) and natural pH substrate (4.9–5.4) for 88 h at a controlled temperature of 30 °C, with measurements of gas production and observations of changes in dissolved oxygen (DO), oxidation-reduction potential (ORP), and substrate pH taken at 4-h intervals. Rhodopseudomonas palustris bacteria was identified as indigenous bacteria for photo-fermentation in POME. The yield, gas production rate, and light conversion efficiency (LCE) were found to be 147.65 mg-H2/L-Depome, 1.68 mg-H2/L-Depome/h, and 11.75 % under the initial pH neutralization treatment, while without initial pH treatment, the values were 78.5 mg-H2/L-Depome, 0.89 mg-H2/L-Depome/h, and 6.25 %.

Biohydrogen Production from Buckwheat Residue Using Anaerobic Mixed Bacteria

In the world, wastes/residues from agricultural activities are rapidly increasing, causing environmental problems. These wastes/residues can be used for the production of biohydrogen as a raw material. In this context, buckwheat crop residue, which has not been found in any study on biohydrogen production potential in the literature research, was investigated for biological hydrogen production via the dark fermentation method. This study was conducted in anaerobic batch bioreactors containing buckwheat or buckwheat extract + pretreated anaerobic mixed bacteria + nutrients, in a darkroom, at 37 ± 1 °C. Gas analyses, organic acid analyses and taxonomic content analyses were performed in bioreactors under different operating conditions (initial pH and organic loading rate). Biological hydrogen production was determined in all bioreactors. In addition, hydrogen production was found to be higher in bioreactors where biomass was used directly. The maximum biohydrogen production was determined to be 11,749.10−4 mL at 1.20 g. buckwheat/L and 446.10−4 mL at 1.20 g. buckwheat extract/L at pH 4.5. According to the taxonomic content species’ level ratios, (i) in bioreactors where biomass was used directly, Hathewaya histolytica and Clostridium butyricum were detected at pH values of 4.5 and 4.0, respectively; and (ii) in bioreactors where biomass extract liquid was used, Clostridium butyricum and Clostridium tertium were determined as the most dominant bacteria at pH values of 4.5 and 4.0, respectively.

Evaluation of short-circuited electrodes in combination with dark fermentation for promoting biohydrogen production process

Short-circuited electrodes, in combination with dark fermentation, were evaluated in a biohydrogen production process. The system is based on an innovative design of a non-compartmented electromicrobial bioreactor with a conductive tubular membrane as cathode and a graphite felt as anode. In particular, the electrode specialization occurred when the bioreactor was inoculated with manure as the whole medium and when a vacuum was applied in the tubular membrane, for allowing continuous extraction of gaseous species (H2, CH4, CO2) from the bioreactor. This specialization of the electrodes as anode and cathode was further confirmed by microbial ecology analysis of biofilms and by cyclic voltammetry measurements. In these experimental conditions, the potential of the electrochemical system (short-circuited electrodes) reached values as low as −320 mV vs. SHE, associated with a significant bioH2 production. Moreover, a higher bioH2 production occurred and a potential of the electrochemical system as low as −429 mV vs SHE was temporarily observed, when additional heat treatments of the whole manure were applied in order to remove methanogen microorganisms (i.e., hydrogen consumers). In the bioreactor, the higher production of bioH2 would be promoted by electrofermentation from the current flow observed between short-circuited anode and cathode.

Synergetic effects of conductive materials and bacterial population in inoculum on mixed-culture biohydrogen production

This study examined the effect of conductive materials (softwood pellet biochar pyrolyzed at 550 °C and 700 °C, powdered activated carbon and stainless-steel) on the two series of batch biohydrogen production inoculated with three types of heated-treated anaerobic digester sludge. Biochar pyrolyzed at 550 °C and stainless-steel exhibited the highest enhanced hydrogen yield up to 117 % in the first and second series of experiments, respectively. Importantly, the enhancement effect by the introduction of conductive materials was significantly affected by the microbial population in inoculum, particularly the relative abundance of electroactive H2-producing Clostridium sp. Metabolic flux analysis revealed that the enhanced H2 yield was concurrent with the decrease of lactate production and the increase of H2-producing acetogenesis. Conductive materials also improved electron transport system activity and NADH/NAD+ ratio, which are related with the metabolic activity. This study shows that introducing conductive material can control intracellular redox environment, thereby reinforcing the metabolic activity selectively.

Impact of light spectra on photo-fermentative biohydrogen production by Rhodobacter sphaeroides KKU-PS1

Purple non-sulphur bacteria can only capture up to 10 % light spectra and only 1–5 % of light is converted efficiently for biohydrogen production. To enhance light capture and conversion efficiencies, it is necessary to understand the impact of various light spectra on light harvesting pigments. During photo-fermentation, Rhodobacter sphaeroides KKU-PS1 cultivated at 30 °C and 150 rpm under different light spectra has been investigated. Results revealed that red light is more beneficial for biomass accumulation, whereas green light showed the greatest impact on photo-fermentative biohydrogen production. Light conversion efficiency by green light is 2-folds of that under control white light, hence photo-hydrogen productivity is ranked as green > red > orange > violet > blue > yellow. These experimental data demonstrated that green and red lights are essential for photo-hydrogen and biomass productions of R. sphaeroides and a clearer understanding that possibly pave the way for further photosynthetic enhancement research.

Stenotrophomonas goyi sp. nov., a novel bacterium associated with the alga Chlamydomonas reinhardtii

Background A culture of the green algae Chlamydomonas reinhardtii was accidentally contaminated with three different bacteria in our laboratory facilities. This contaminated alga culture showed increased algal biohydrogen production. These three bacteria were independently isolated. Methods The chromosomic DNA of one of the isolated bacteria was extracted and sequenced using PacBio technology. Tentative genome annotation (RAST server) and phylogenetic trees analysis (TYGS server) were conducted. Diverse growth tests were assayed for the bacterium and for the alga-bacterium consortium. Results Phylogenetic analysis indicates that the bacterium is a novel member of the Stenotrophomonas genus that has been termed in this work as S. goyi sp. nov. A fully sequenced genome (4,487,389 base pairs) and its tentative annotation (4,147 genes) are provided. The genome information suggests that S. goyi sp. nov. is unable to use sulfate and nitrate as sulfur and nitrogen sources, respectively. Growth tests have confirmed the dependence on the sulfur-containing amino acids methionine and cysteine. S. goyi sp. nov. and Chlamydomonas reinhardtii can establish a mutualistic relationship when cocultured together. Conclusions S. goyi sp. nov. could be of interest for the design of biotechnological approaches based on the use of artificial microalgae-bacteria multispecies consortia that take advantage of the complementary metabolic capacities of their different microorganisms.

Biological H2(g) Production and Modelling with Computational Fluid Dynamics (CFD)

In this study, bio-hydrogen gas [bio-H2(g)] production and modeling with a three-phase computational fluid dynamics (CFD) model, heat and mass transfer of bio-hydrogen production, reaction kinetics, and fluid dynamics; It was investigated by dark fermentation process in an anaerobic continuous plug flow reactor (ACPFR). The three-phase CFD model was used to determine the bio-H2(g) production in an ACPFR. The effect of different operating parameters, increasing hydrolic retention times (HRTs) (1, 2, 4, 8, and 12 days), different pH values (4.0, 5.0, 6.0, 7.0, and 8.0), and increasing feed rate as organic loading rates (OLRs) (0.5, 1.0, 2.0, 4.0, 8.0 and 10.0 g COD/l.d) on the bio-H2(g) production rates were operated in municipal sludge wastes (MSW) with Thermoanaerobacterium thermosaccharolyticum SP-H2 methane bacteria during dark fermentation for bio-H2(g) production. The effect of HRT, pH, and feed rate on the bioH2(g) efficiencies and H2(g) production rates were examined in the simulation stage. Production of volatile fatty acids (VFAs) namely, acetic acids, butyric acids, and propionic acids were important points influencing the bio-H2(g) production yields. The artificial neural network (ANN) model substrate inhibition on bio-H2(g) production to the methane (CH4) bacteria was also investigated. The reaction kinetics model used Thermotoga neapolitana microorganisms with the Andrews model of substrate inhibition. Furthermore, the ANN model was well-fitted to the experimental data to simulate the bio-H2(g) production from chemical oxygen demand (COD).

Simulation and optimization for biohydrogen production potential of various organic waste via anaerobic digestion

A simulation model was developed for biohydrogen production from organic feeds such as cow dung (CD), banana stem (BS), and waste paper pulps (WPP). Data from the model was used to generate a design of experiment (DoE) that analysed the data and optimizes the input parameters for optimized biohydrogen yield. Three input parameters taken for optimization were pretreatment temperature (PTT), hydraulic retention time (HRT), and feed-to-water (F/W) ratio. Results showed the optimal sequence of influencing parameters is PTT > HRT > F/W ratio. The optimal value of PTT was 75 ℃ for all feeds. In contrast, the HRT and F/W ratios were 13.1 days and 0.5 ratio for CD, 16.6 days and 1.5 ratio for BS, and 11.7 days and 1.4 ratio for WPP. At the same time, the optimal biohydrogen yield was 24.59 % (CD), 25.27 % (BS), and 24.21 % (WPP). Therefore, the current simulation and optimization had convincing results in optimizing commercial plants' biohydrogen production.

Cleaner production of biohydrogen using poplar leaves: Experimental and optimization studies

Biohydrogen (bioH2) is recognized as a potential carbon-neutral energy vector, and developing novel methods has received increasing attention with a prime goal of producing H2 more efficient and cost effective manner. This study aimed to develop a unique reactor to investigate dark fermentative H2 production from poplar biomass using commercially available and inexpensive microorganism cultures. Therefore, six factors of the Box-Behnken design (BBD) were performed to evaluate the individual and combined effects of operational parameters: acid concentration (2–10%), biomass concentration (2–10 g), initial pH (5–8), temperature (30–40 °C), mixing ratio (150–350 rpm), and microorganism concentration (2–6 g) on bioH2 production. Among the operational parameters, the acid concentration was the most effective parameter on bioH2 production. The bioH2 production increased from 11.33 to 18.15 mg/g biomass with increasing acid concentration from 6 to 10%. Moreover, the optimum levels of operational variables were as follows: acid concentration of 9.9%, biomass amount of 2 g, pH of 6.56, temperature of 35 °C, mixing ratio of 345 rpm, and microorganism amount of 4.5 g for the highest bioH2 production of 20 mg/g-biomass according to the experimental design. Consequently, the bioH2 production performance of the dark fermentation process showed that bioH2 production from poplar biomass using commercially available microorganisms had a competitive advantage.

Influence of organic carbon source on hydrogen production and nutrient removal by microbial consortium in anaerobic photobioreactors

Microalgae and cyanobacteria interactions with autochthonous bacteria have been demonstrated as a feasible alternative for biohydrogen production and wastewater treatment. In the present study, hydrogen production and nutrient removal from different organic carbon sources (glycerin, sucrose, glucose and organic acids, and pentose-rich liquor) by microbial consortia through biophotolysis and photofermentation in batch anaerobic bioreactors have been evaluated. Chlamydomonas sp. strains (CC425, CC4169, and CHL02) demonstrated higher hydrogen production from sucrose-enriched wastewater, 4.33 ± 0.25 mmol H2 L−1 (CC425) and 1.02 ± 0.25 mmol H2 L−1 (CHL02), and better organic carbon removal, 66.0 % (CC4169). Anabaena sp. (UTEX1448) yielded better nitrogen removal (average of 31.6 %) and promising results of hydrogen production from pentose-rich liquor. The results showed that the organic carbon source influenced hydrogen production due to the occurrence of different metabolic pathways by microbial consortia and that this production can be associated with the biological wastewater treatment.

Production of biomethane, biohydrogen, and volatile fatty acids from Nordic phytoplankton biomass grown in blended wastewater

Upgrading carbon-negative microalgal biomass to biofuels and value-added products presents a three-pronged solution for waste treatment, carbon capture, and economically viable bioenergy production. Acidogenesis and methanogenesis are versatile processes at the core of anaerobic digestion systems, facilitating the conversion of diverse biogenic substrates into energy and a wide range of biobased products. The present study was conducted to integrate acidogenesis and methanogenesis for coproduction of biohydrogen, biomethane, and volatile fatty acids from Nordic phytoplankton consortia. For this purpose, microalgal consortia was cultivated in a raceway pond equipped with high surface area structures. Harvested microalgal biomass was subjected to thermoalkaline (2% NaOH solution at 121 °C) and enzymatic (cellulase) pretreatments. The hydrolysates of the pretreated biomass were inoculated with thermally treated sludge for acidogenic fermentation and with mixture of untreated sludge and cow dung (1:1 v/v ratio) for anerobic digestion. The acidogenic process produced a significant amount of biohydrogen (maximum 164.8 mL bioH2/VSload) along with volatile fatty acids (maximum 7.9 g COD/L), while methanogenesis resulted in biomethane production of maximum 210.7 mL bioCH4/VSload, accompanied by an ammonium recovery of 1278 mg NH4+/L. These maximum yields were all achieved by enzymatic pretreatment of the biomass fraction harvested from high surface area brush head structures inserted in the raceway pond. These results have important implications for designing phytoplankton cultivation systems and upstream pathways to optimize energy production from carbon-negative phytoplankton biomass.

Biohydrogen production from lactic acid: Use of food waste as substrate and evaluation of pretreated sludge and native microbial community as inoculum

Nowadays, lactic acid (HLa) has caught the eye as a precursor of H2 production from substrates that harbor a significant amount of lactic acid bacteria (LAB), such as Lactobacillus and Lactococcus. Since the native microbial community of food waste (FW) is dominated by LAB, the production of H2 during dark fermentation might be inhibited by the displacement of H2-producing bacteria by LAB. Therefore, lactate-driven dark fermentation in two steps is an alternative to overcome the overproliferation of LAB. In this process, FW is converted into HLa, which can subsequently be transformed into H2 by HLa-consuming bacteria during a cross-feeding mechanism with H2-producing bacteria. In the present study, FW was evaluated for HLa production at different organic loading rates (OLR) (12.5, 25.0, 37.5, and 50.0 gVS/L/d) in a semi-continuous reactor, and the HLa obtained was used for the H2 production. Results showed that OLR significantly influences HLa production during the self-fermentation of FW (p < 0.05). The highest ORL of 50.0 gVS/L/d and an HRT of 1.25 days generated the net maximum HLa production of 10.8 g/L. The HLa production was companied by the presence of acetate, propionate, and succinate, which accounted for only 20 % of the total organic acids produced. Then, effluent with HLa concentrations of 5.0, 10.0, 15.0, 20.0, and 25.0 g/L was evaluated for H2 production in batch tests using thermally pretreated sludge and the native microbial community of the effluent as inoculum. Even though different metabolic pathways for H2 production can be noted during the fermentation, which differs from one inoculum to another, the highest value of H2 production of 596.3 mL/Lreactor was obtained with the native microbial community at the highest concentration of HLa (25.0 g/L). During the fermentation process for H2 production, HLa and propionate were mainly transformed into butyrate and acetate. The present study demonstrated the feasibility of obtaining H2 from a complex substrate, such as effluent from a previous fermentation, using different inocula.

Development and techno-economic analysis of Calophyllum inophyllum biorefinery for the production of biodiesel, biohydrogen, bio-oil, and biochar: Waste to energy approach

Development and techno-economic analysis of Calophyllum inophyllum biorefinery for the production of biodiesel, biohydrogen, bio-oil, and biochar: Waste to energy approach

Application of Escherichia coli and Enterobacter aerogenes as Electroactive Bacteria for Bio-Hydrogen Production in Microbial Electrolysis Cells

Application of Escherichia coli and Enterobacter aerogenes as Electroactive Bacteria for Bio-Hydrogen Production in Microbial Electrolysis Cells

A Systematic Review on Photocatalytic Biohydrogen Production from Waste Biomass

A Systematic Review on Photocatalytic Biohydrogen Production from Waste Biomass

Biological production of hydrogen: From basic principles to the latest advances in process improvement

The development of net-zero emission fuels is a priority area of modern research due to the imminent reduction of fossil fuel reserves and environmental problems caused by their combustion. One of the promising fuels is hydrogen, which has a high heat of combustion and is eco-friendly, forms water as the only byproduct. Recently, methods of hydrogen production by microorganisms, which use directly the solar energy or utilize the organic waste during fermentation, have been intensively developed and applied. In this review, the basic principles of the main light-dependent (biophotolysis, photofermentation) and light-independent (dark fermentation and microbial electrolysis) methods of biological hydrogen production are discussed. Particular attention is paid to the advantages and disadvantages of these methods, the possibility of combining them into a single system, as well as various strategies for improving biohydrogen production aimed at transition from laboratory research to full-scale application.

Nanomaterials mediated valorization of agriculture waste residue for biohydrogen production

Hydrogen is consider as clean fuel with potential source of unlimited clean power. The global market for the hydrogen generation is expected to be $317.39 billion by 2030. The key factors responsible for hydrogen generation market includes high demand of conventional fuel in steel, cement and power generation industries and government initiatives for green and sustainable environment. It is of the utmost note that the major production of hydrogen is based on conversion from fossil fuels such as coal, petroleum etc. Among green hydrogen production method transformation of biomass to biohydrogen via anaerobic fermentation is considered as carbon neutral source of energy. However, the yield of hydrogen production is low and depends upon various factors such waste composition, bioreactor type, and microorganisms used its production, but production is limited due to shortage of raw materials. Since, the biomass such as agriculture waste residues are largely available as corn stover, sugar beet juice, beverage waste; water, wheat straw, rice straw, wood chips, sawdust, shrubs, and branches etc. The major hurdle in dark fermentation is lower biohydrogen yield due to inefficient conversion of carbohydrates into biohydrogen. Nanomaterials can help in valorization of agriculture residue for efficient biohydrogen production. Nano-technological application like increasing surface area, enzyme stability and saccharification efficiency of enzyme can contribute in biohydrogen production. Nanoparticles may result in a shift in the microbial community and the metabolic pathway for hydrogen production. This review explore the impending application of nanomaterial for valorization of agriculture biomass, biochemical pathways, and possible application of nanomaterial as individual or in composite to improve biohydrogen production.

Potential of Bacillus subtilis as oxygen-removal agent for biohydrogen production by Clostridium acetobutylicum

Molasses are a source of fermentable sugars, the substrate utilized for this study, as it is a subproduct from sugarcane processing for sucrose recovery. These sugars can be metabolized for bioH2 production by bacterial strains, particularly strict-anaerobe Clostridium acetobutylicum (Clac) and its media preparation requires chemical of O2 removal and N2 flushing to promote anaerobiosis. Bacillus subtilis (Bsub) can deplete O2 from culture media and promotes anaerobiosis, which is an aspect that would benefit from further research. Clac was grown in an anaerobic medium and produced 269 mL of hydrogen at 72 h. By co-culturing Clac and Bsub, 502 mL of bioH2 were produced in a cysteine/N2 flushed medium, while 203 mL of bioH2 at 72 h were produced by aerobic co-culture. Additionally, in an untreated/aerobic conventional growth culture for Clac, no production of H2 was detected, reinforcing the utility of Bsub for anaerobiosis generation.

Improved estimation of dark fermentation biohydrogen production utilizing a robust categorical boosting machine-learning algorithm

Dark fermentation is attracting great attention due to some capabilities such as wastewater treatment and biofuel production. In this study, the performance of different machine learning algorithms, including Bagging-Extreme Gradient Boosting (BagXGBoost), Categorical Boosting (CatBoost), K Nearest Neighborhood (KNN), Light Gradient Boosting Machine (LightGBM), and Decision Trees (DT) in the prediction of biohydrogen production from wastewater during dark fermentation is investigated. Effect of parameters Ni, Fe, biomass, pH, chemical oxygen demand (COD), HRT, acetate, ethanol, butyrate, and acetate/butyrate ratio as inputs were considered for the model development. A databank with 208 data points was culled from the literature. For the validation of the proposed models, various statistical criteria were determined. CatBoost and BagXGBoost exhibited superior performance in predicting fermentative hydrogen (H2) production. Shapley additive explanations were used for relative analysis, revealing the highest absolute SHAP values of 1.1, 1, and 0.07 for COD, nickel, and butyrate, respectively, highlighting their significance in H2 production. The insights gained from this study can contribute to further optimization of the dark biohydrogen fermentation process.