Treatment of industrial wastewaters by algae-bacterial consortium with Bio-H2 production: Recent updates, challenges and future prospects.

Currently, scarcity/security of clean water and energy resources are the most serious problems worldwide. Industries use large volume of ground water and a variety of chemicals to manufacture the products and discharge large volume of wastewater into environment, which causes severe impacts on environment and public health. Fossil fuels are considered as major energy resources for electricity and transportation sectors, which release large amount of CO2 and micro/macro pollutants, leading to cause the global warming and public health hazards. Therefore, algae-bacterial consortium (A-BC) may be eco-friendly, cost-effective and sustainable alternative way to treat the industrial wastewaters (IWWs) with Bio-H2 production. A-BC has potential to reduce the global warming and eutrophication. It also protects environment and public health as it converts toxic IWWs into non or less toxic (biomass). It also reduces 94%, 90% and 50% input costs of nutrients, freshwater and energy, respectively during IWWs treatment and Bio-H2 production. Most importantly, it produce sustainable alternative (Bio-H2) to replace use of fossil fuels and fill the world's energy demand in eco-friendly manner. Thus, this review paper provides a detailed knowledge on industrial wastewaters, their pollutants and toxic effects on water/soil/plant/humans and animals. It also provides an overview on A-BC, IWWs treatment, Bio-H2 production, fermentation process and its enhancement methods. Further, various molecular and analytical techniques are also discussed to characterize the A-BC structure, interactions, metabolites and Bio-H2 yield. The significance of A-BC, recent update, challenges and future prospects are also discussed.

Bio-hydrogen-producing Potential Evaluation and Capacity Enhancement from Tobacco Processing Leftovers by Photo-fermentation Under Diverse Initial pH.

The use of tobacco growing and processing residues for bio-hydrogen production is an effective exploration to broaden the source of bio-hydrogen production raw materials and realize waste recycling. In this study, bio-hydrogen-producing potential was evaluated and the effect of diverse initial pH on hydrogen production performance was investigated. The cumulative hydrogen yield (CHY) and the properties of fermentation liquid were monitored. The modified Gompertz model was adopted to analyze the kinetic characteristics of photo-fermentation bio-hydrogen production process. Results showed that CHY increased firstly and then decreased with the increase of initial pH. Highest CHY and hydrogen production rate of appeared at the initial pH of 8, which were 257.7 mL and 6.15 mL/h, respectively. The acidic initial pH was found to severely limit the bio-hydrogen production capacity. The correlation coefficients (R2) of hydrogen production kinetics parameters were all greater than 0.99, meaning that the fitting effect was good. The main metabolites of bacteria in the system were acetic acid, butyric acid, and ethanol, and the consumption of acetic acid was promoted with the increase of initial pH.

Enhancing bio-hydrogen and bio-methane production of concentrated latex wastewater (CLW) by Co-digesting with palm oil mill effluent (POME): Batch and continuous performance test and ADM-1 modeling.

This study aimed at investigating the biohydrogen and biomethane potential of co-digestion from palm oil mill effluent (POME) and concentrated latex wastewater (CLW) in a two-stage anaerobic digestion (AD) process under thermophilic (55 ± 3 °C) and at an ambient temperature (30 ± 3 °C) conditions, respectively. The batch experiments of POME:CLW mixing ratios of 100:0, 70:30, 50:50, 30:70, and 0:100 was investigated with the initial loadings at 10 g-VS/L. The highest hydrogen yield of 115.57 mLH2/g-VS was obtained from the POME: CLW mixing ratio of 100:0 with 29.0 of C/N ratio. While, the highest subsequent methane production yield of 558.01 mLCH4/g-VS was achieved from hydrogen effluent from POME:CLW mixing ratio of 70:30 0 with 21.8 of C/N ratio. This mixing ratio revealed the highest synergisms of about 9.21% and received maximum total energy of 19.70 kJ/g-VS. Additionally, continuous hydrogen and methane production were subsequently performed in a series of continuous stirred tank reactor (CSTR) and up-flow anaerobic sludge blanket reactor (UASB) to treat the co-substate. The results indicated that the highest hydrogen yield of POME:CLW mixing ratio at 70:30 of 95.45 mL-H2/g-VS was generated at 7-day HRT, while methane production was obtained from HRT 15 days with a yield of 204.52 mL-CH4/g-VS. Thus, the study indicated that biogas production yield of CLW could be enhanced by co-digesting with POME. In addition, the two-stage AD model under anaerobic digestion model no. 1 (ADM-1) framework was established, 9.10% and 2.43% of error fitting of hydrogen and methane gas between model simulation data and experimental data were found. Hence, this research work presents a novel approach for optimization and feasibility for co-digestion of POME with CLW to generate mixed gaseous biofuel potentially.

A review on biological biohydrogen production: Outlook on genetic strain enhancements, reactor model and techno-economics analysis.

Modernisation of industrial and transportation sector would have not imaginable without the help of fossil fuels, but constant usage has led to many environmental concerns. As a step forward, for safer next generation living we are forced to look into green fuels like bio­hydrogen and higher alcohols. This review mainly focuses on bio­hydrogen production via biological pathways, genetic improvements, knowledge gap, economics, and future directions. Dark and photo fermentation process with the factor influence the process (pH regulation, temperature, hydraulic retention time, organic loading rate, Maintenance, Nutrient) is studied. Integration of dark fermentation and microbial electrolysis cell is the most trending progression for sustainable bio­hydrogen production. Genetic improvement of microbe for biohydrogen production via inactivation of hydrogenase (H2ase) and improve oxygen tolerant H2ase. In future, bioaugmentation, multidisciplinary integrated process and microbial electrolysis needs to be experimented in industrial level scale for successful commercialization. About 41.47 mmol H2/g DCW h at 40 g/L of optimum biohydrogen production was obtained through glycerol fermentation. From the studies, the cost of biohydrogen production was found to high with respect to the direct bio photolysis it cost around $7.24 kg-1; for indirect bio photolysis it cost around $7.54 kg-1 and for fermentation it cost around $7.61 kg-1.

Enhanced biohydrogen yield and light conversion efficiency during photo-fermentation using immobilized photo-catalytic nano-particles.

Bacterial immobilization is a common method in anaerobic fermentation, since of the maintenance of high bacterial activity, insurance of high density microbial during continuous fermentation, and quick adaptability to the environment. While, the bio-hydrogen production capacity of immobilized photosynthetic bacteria (I-PSB) is seriously affected by the low light transfer efficiency. Hence, in this study, photo-catalytic nano-particles (PNPs) was added into the photo-fermentative bio-hydrogen production (PFHP) system, and its enhancement effects of bio-hydrogen production performance were investigated. Results showed that the maximum cumulative hydrogen yield (CHY) of I-PSB with 100 mg/L nano-SnO2 (154.33 ± 7.33 mL) addition was 18.54% and 33.06% higher than those of I-PSB without nano-SnO2 addition and control group (free cells), and the lag time was the shortest indicating a shorter cell arrest time, more cells and faster response. Maximum energy recovery efficiency and light conversion efficiency were also found to be increased by 18.5% and 12.4%, respectively.

Two-Stage Bio-Hydrogen and Polyhydroxyalkanoate Production: Upcycling of Spent Coffee Grounds.

Coffee waste is an abundant biomass that can be converted into high value chemical products, and is used in various renewable biological processes. In this study, oil was extracted from spent coffee grounds (SCGs) and used for polyhydroxyalkanoate (PHA) production through Pseudomonas resinovorans. The oil-extracted SCGs (OESCGs) were hydrolyzed and used for biohydrogen production through Clostridium butyricum DSM10702. The oil extraction yield through n-hexane was 14.4%, which accounted for 97% of the oil present in the SCGs. OESCG hydrolysate (OESCGH) had a sugar concentration of 32.26 g/L, which was 15.4% higher than that of the SCG hydrolysate (SCGH) (27.96 g/L). Hydrogen production using these substrates was 181.19 mL and 136.58 mL in OESCGH and SCGH media, respectively. The consumed sugar concentration was 6.77 g/L in OESCGH and 5.09 g/L in SCGH media. VFA production with OESCGH (3.58 g/L) increased by 40.9% compared with SCGH (2.54 g/L). In addition, in a fed-batch culture using the extracted oil, cell dry weight was 5.4 g/L, PHA was 1.6 g/L, and PHA contents were 29.5% at 24 h.

Influence of Nanomaterials and Other Factors on Biohydrogen Production Rates in Microbial Electrolysis Cells-A Review.

Microbial Electrolysis Cells (MECs) are one of the bioreactors that have been used to produce bio-hydrogen by biological methods. The objective of this comprehensive review is to study the effects of MEC configuration (single-chamber and double-chamber), electrode materials (anode and cathode), substrates (sodium acetate, glucose, glycerol, domestic wastewater and industrial wastewater), pH, temperature, applied voltage and nanomaterials at maximum bio-hydrogen production rates (Bio-HPR). The obtained results were summarized based on the use of nanomaterials as electrodes, substrates, pH, temperature, applied voltage, Bio-HPR, columbic efficiency (CE) and cathode bio-hydrogen recovery (C Bio-HR). At the end of this review, future challenges for improving bio-hydrogen production in the MEC are also discussed.

Household food waste conversion to biohydrogen via steam gasification over copper and nickel-loaded SBA-15 catalysts.

Household food waste (FW) was converted into biohydrogen-rich gas via steam gasification over Ni and bimetallic Ni (Cu-Ni and Co-Ni) catalysts supported on mesoporous SBA-15. The effect of catalyst method on steam gasification efficiency of each catalyst was investigated using incipient wetness impregnation, deposition precipitation, and ethylenediaminetetraacetic acid metal complex impregnation methods. H2-TPR confirmed the synergistic interaction of the dopants (Co and Cu) and Ni. Furthermore, XRD and HR-TEM revealed that the size of the Ni particle varied depending on the method of catalyst synthesis, confirming the formation of solid solutions in Co- or Cu-doped Ni/SBA-15 catalysts due to dopant insertion into the Ni. Notably, the exceptional activity of the Cu-Ni/SBA-15-EMC catalyst in FW steam gasification was attributed to the fine distribution of the concise Ni nanoparticles (9 nm), which resulted in the highest hydrogen selectivity (62 vol%), gas yield (73.6 wt%). Likewise, Cu-Ni solid solution decreased coke to 0.08 wt%.

Dataset of response characteristics of H2-producing bacteria consortium to ß-lactams, aminoglycosides, macrolides, quinolones antibiotics.

Antibiotics on H2 producing bacteria shall be considered as being one of the critical elements in biological H2 production utilizing livestock manure as raw resources. Despite the fact that the manure stands a significance role in bio-fermentation, the possibility of antibiotics being contained in excreta shall not be eliminated. Findings of whether the above saying might threaten the safety of bio-H2 production needs to be further studied. The experiment subjects include: six single and three combined antibiotics were tested and analyzed by the application of the gradient experiment method. Along with the H2 production rate, CHO content, pH and OD600 were used to analyze the effects of various antibiotics introduction on the hydrolysis, fermentation and H2 production. To a further extent, four typical representative samples were selected for biodiversity analysis from the single antibiotic experiment groups. Amounting more than 6000 pieces of data were obtained in a series of experiments. Data suggested that remarkable measure of antibiotics have various degrees of H2 production inhibition, while some antibiotics, Penicillin G, Streptomycin Sulfate, and their compound antibiotics, could promote the growth of Ethanoligenens sp. and improve H2 yield in the contrary. Correspondent to the transition of key metabolic intermediates and end products, the mechanism of each antibiotic type and dose on H2 production were summarized as follows: the main inhibitory mechanisms were: (1) board-spectrum inhibition, (2) partial inhibition, (3) H2 consumption enhancement; and the enhancement mechanisms were: (1) enhance the growth of H2-producing bacteria, (2) enhanced starch hydrolysis, (3) inhibitory H2 consumption or release of acid inhibition. Meanwhile, data analysis found that the effect of antibiotics on H2 producing was not only related to type, but also to dosage. Even one kind of antibiotic may have completely opposite effects on H2-producing bacteria under different dosage conditions. Inhibition of H2 yield was highest with Levofloxacin at 6.15 mg/L, gas production was reduced by 88.77%; and enhancement of H2 yield was highest with Penicillin G at 7.20 mg/L, the gas production increased by 72.90%.

Unraveling the roles of lanthanum-iron oxide nanoparticles in biohydrogen production.

Low hydrogen (H2) yield via dark fermentation often occurs, being mainly due to H2 generation pathway shift. In this study, lanthanum-iron oxide nanoparticles (LaFeO3 NPs) were prepared to investigate their effects on bioH2 production. The highest H2 yield of 289.8 mL/g glucose was found at 100 mg/L of LaFeO3, being 47.6% higher than that from the control (196.3 mL/g glucose). The relative abundance of Firmicutes increased from 54.2% to 67.5%. The large specific surface area of LaFeO3 provided sufficient sites for the colonization of Firmicutes and increased the bacterial access to nutrients. Additionally, the La3+ gradually released from LaFeO3 NPs raised microbial transmembrane transport capacity, promoting glycolytic efficiency and Fe availability, thereby increasing hydrogenase content, and shifting the bioH2 evolution to butyrate pathway for more H2. This provides the novelty for biochemical utilization of La and new insights into the improved H2 yield amended with LaFeO3.

Surfactant induced microwave disintegration for enhanced biohydrogen production from macroalgae biomass: Thermodynamics and energetics.

This research work aimed about the enhanced bio-hydrogen production from marine macro algal biomass (Ulva reticulate) through surfactant induced microwave disintegration (SIMD). Microwave disintegration (MD) was performed by varying the power from 90 to 630 W and time from 0 to 40 min. The maximum chemical oxygen demand (COD) solubilisation of 27.9% was achieved for MD at the optimal power (40%). A surfactant, ammonium dodecyl sulphate (ADS) is introduced in optimal power of MD which enhanced the solubilisation to 34.2% at 0.0035 g ADS/g TS dosage. The combined SIMD pretreatment significantly reduce the treatment time and increases the COD solubilisation when compared to MD. Maximum hydrogen yield of 54.9 mL H2 /g COD was observed for SIMD than other samples. In energy analysis, it was identified that SIMD was energy efficient process compared to others since SIMD achieved energy ratio of 1.04 which is higher than MD (0.38).

Effect of 5-HMF and furfural additives on bio-hydrogen production by photo-fermentation from giant reed.

Substances harmful to photo-fermentative biological hydrogen production (PFHP) were produced during cellulose hydrolysis. This study aimed to evaluate the effect of by-products (5-hydroxymethylfurfural (5-HMF) and furfural) released from lignocellulose during enzymatic hydrolysis process on PFHP. The exist of 5-HMF inhibited the hydrogen production. However, 0.2 g/L furfural improved the hydrogen production by 19 % compared to no addition (511.6 mL) with a maximum concentration of nitrogenase (109.96 IU/L) at 96 h. Furthermore, a 18.7 % enhancement of hydrogen production was also observed when 0.2 g/L 5-HMF and furfural were mixed at a ratio of 1:1, while decrement of hydrogen production at higher addition was observed as well. Through the scatter matrix analysis, it was concluded that 5-HMF and furfural additives had significant effects on PFHP. This study gave an insight into effect of lignocellulosic by-products on biohydrogen production.

Comparison of three ionic liquids pretreatment of Arundo donax L. For enhanced photo-fermentative hydrogen production.

Ionic liquids (ILs) pretreatment has been regarded as a promising green way to treat lignocellulosic biomass. 1-Butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4), 1-allyl-3-methylimidazolium chloride ([Amim]Cl), and 1-Butyl-3-methylimidazolium Hydrogen Sulfate ([Bmim]HSO4) with different loadings (2, 4, 8, and 16 g/L) were adopted to pretreat the Arundo donax L.. 16 g/L [Bmim]HSO4 pretreated Arundo donax L. obtained the highest sugar yield of 7.9 g/L during the enzymatic hydrolysis and hydrogen yield of 106.1 mL/g TS during the photo-fermentation, which were 68.8 % and 35.3 % higher than those of untreated Arundo donax L., respectively. Moreover, volatile fatty acids (VFAs) distribution revealed that acetic acid was the main by-product during hydrogen production process with ILs pretreated Arundo donax L.. Besides, the relationship between sugar yield and hydrogen yield was the closest based on scatter matrix analysis. This study helps to understand of correlation between ILs pretreatment with the behavior of bioenergy production.

Bio-Hydrogen Production Using Landfill Leachate Considering Different Photo-Fermentation Processes.

Recently, it has become imperative to find new sustainable and renewable sources of energy, in order to avoid dependence on non-renewable traditional energy resources. This would help to overcome the depleting of natural resources for energy production. Hydrogen gas production using biological processes is one of the most attractive solutions in this regard, due to its high energy content and ecofriendly nature. Production of hydrogen using single photo-fermentation process and landfill leachate as substrate was carried out in this paper, by utilizing batch bio-reactor and anaerobic conditions. The pH value and temperature, play an essential role in a bio-hydrogen production process. Thus, in this study, the pH values considered were 6, 6.5, and 7.2, respectively, at a controlled temperature of 37 ± 1°C. This study investigated various schemes that have the possibility of producing hydrogen using; landfill leachate alone, with leachate and addition of inoculum such as sewage sludge, and with substrate such as sucrose and glucose. All experiments were conducted with and without mixing, for effective comparative study. Heat and pH pretreatment were applied in each experiment with the objectives of decreasing the activities of methane-producing bacteria and enhancing the activities of hydrogen-producing bacteria. The hydraulic retention time used in this study was 48 h, in order to obtain optimal performance of the schemes employed. Analysis of liquid leachate was performed for each experiment, and based on the obtained results, the maximum yield of hydrogen produced was 5,754 ml H2/L, with a medium pH scale of 6.0, fermentation temperature of 37 ± 1°C and constant mixing speed of 100 rpm.

Improving sustainable hydrogen production from green waste: [FeFe]-hydrogenases quantitative gene expression RT-qPCR analysis in presence of autochthonous consortia.

BACKGROUND: Bio-hydrogen production via dark fermentation of low-value waste is a potent and simple mean of recovering energy, maximising the harvesting of reducing equivalents to produce the cleanest fuel amongst renewables. Following several position papers from companies and public bodies, the hydrogen economy is regaining interest, especially in combination with circular economy and the environmental benefits of short local supply chains, aiming at zero net emission of greenhouse gases (GHG). The biomasses attracting the largest interest are agricultural and urban green wastes (pruning of trees, collected leaves, grass clippings from public parks and boulevards), which are usually employed in compost production, with some concerns over the GHG emission during the process. Here, an alternative application of green wastes, low-value compost and intermediate products (partially composted but unsuitable for completing the process) is studied, pointing at the autochthonous microbial consortium as an already selected source of implementation for biomass degradation and hydrogen production. The biocatalysts investigated as mainly relevant for hydrogen production were the [FeFe]-hydrogenases expressed in Clostridia, given their very high turnover rates. RESULTS: Bio-hydrogen accumulation was related to the modulation of gene expression of multiple [FeFe]-hydrogenases from two strains (Clostridium beijerinckii AM2 and Clostridium tyrobutyricum AM6) isolated from the same waste. Reverse Transcriptase quantitative PCR (RT-qPCR) was applied over a period of 288 h and the RT-qPCR results showed that C. beijerinckii AM2 prevailed over C. tyrobutyricum AM6 and a high expression modulation of the 6 different [FeFe]-hydrogenase genes of C. beijerinckii in the first 23 h was observed, sustaining cumulative hydrogen production of 0.6 to 1.2 ml H2/g VS (volatile solids). These results are promising in terms of hydrogen yields, given that no pre-treatment was applied, and suggested a complex cellular regulation, linking the performance of dark fermentation with key functional genes involved in bio-H2 production in presence of the autochthonous consortium, with different roles, time, and mode of expression of the involved hydrogenases. CONCLUSIONS: An applicative outcome of the hydrogenases genes quantitative expression analysis can be foreseen in optimising (on the basis of the acquired functional data) hydrogen production from a nutrient-poor green waste and/or low added value compost, in a perspective of circular bioeconomy.

Photo-fermentative biohydrogen production from corncob treated by microwave irradiation.

The complex structure of corncob is the bottleneck that restricts its efficient biohydrogen production. Hence, effective treatment is an important exploration to break this limitation. The effect of microwave irradiation (MI) on photo-fermentative biohydrogen production (PFHP) process was evaluated in this paper. Diverse conditions (irradiation time, microwave power, and surfactant addition) were applied. Comparisons of cumulative hydrogen yield (CHY), microstructure, liquid products, and substrate conversion efficiency (Sconv) were conducted. Results showed that the highest CHY of 27.34 ± 1.13 mL/g TS was achieved when the corncob was treated by MI assisted with surfactant addition. Optimal treatment conditions (5.51 min irradiation time, 772.03 W microwave power, and 0.08 g/L rhamnolipids addition) were obtained. MI assisted with surfactant addition helped with the structure destroys and content degradation, displaying a great improves on PFHP. Lower ethanol content and higher butyric acid content were obtained. An 80.94% increase in CHY and Sconv of 90.44% were obtained than untreated corncob.

Experimental study on optimization of initial pH for photo-fermentation bio-hydrogen under different enzymatic hydrolysis of chlorella vulgaris.

In the paper, Use Chlorella as raw material, HAU-M1 Photosynthetic bacteria (PSB) as hydrogen-producing bacteria, the influence of initial pH on bio-hydrogen by photosynthetic organisms from Chlorella vulgaris with diverse enzyme addition was studied. The results showed that when using cellulase as hydrolase, the optimum initial pH was 7.0 and highest bio-hydrogen was 25.99 mL/g dry cell weight. Using neutral protease as hydrolase, the optimum initial pH was 8.0 and highest bio-hydrogen was 16.47 mL/g dry cell weight. Using mixed enzyme of cellulase and protease as hydrolase, the optimal initial pH was 7.0 and highest bio-hydrogen was 27.43 mL/g dry cell weight. The bio-hydrogen from Chlorella after mixed enzymatic hydrolysis is better than that of single enzymatic hydrolysis, we think the mixed enzymatic hydrolysis of cellulase and protease was superior to the single enzymatic hydrolysis of the two enzymes, which provides a scientific reference and low-cost bio-hydrogen technology by microalgae.

Study of the interrelationship between nano-TiO2 addition and photo-fermentative bio-hydrogen production of corn straw.

This study explored the interrelationship between nano-TiO2 addition and photo-fermentative hydrogen production (PFHP) of corn straw. The maximum cumulative hydrogen volume (CHV) was up to 688.8 mL under the optimal photo-fermentative process conditions with nano-TiO2 addition of 300 mg/L. Initial pH and interaction between substrate concentration and light intensity had highly significant effects on PFHP of corn straw with nano-TiO2 addition. With the improvement of CHV, nano-TiO2 addition decreased the optimal initial pH and substrate concentration for PFHP of corn straw. Moreover, nano-TiO2 addition promoted the metabolism of butyric acid and acetic acid by photosynthetic bacteria HAU-M1, and significantly reduced the total concentration of intermediate byproducts during hydrogen production to a low level of 1.6-2.5 g/L, thus making the CHV, maximum hydrogen production rate (HPR) and average hydrogen content (HC) increased by 32.6%, 27.9% and 8.3% respectively over the control without nano-TiO2 addition.

Review on hydrothermal liquefaction aqueous phase as a valuable resource for biofuels, bio-hydrogen and valuable bio-chemicals recovery.

Hydrothermal liquefaction (HTL) of biomass results in the formation of bio-oil, aqueous phase (HTL-AP), bio-char, and gaseous products. Safer disposal of HTL-AP is difficult on an industrial scale since it comprises low molecular acid compounds. This review provides a comprehensive note on the recent articles published on the effective usage of HTL-AP for the recovery of valuable compounds. Thermo-chemical and biological processes are the preferred techniques for the recovery of biofuel, platform chemicals from HTL-AP. From this review, it was evident that the composition of HTL-AP and product recovery are the integrated pathways, which depend on each other. Substitute as reaction medium in HTL process, growth medium for algae and microbes are the most common mode of reuse and recycle of HTL-AP. Future research is needed to depict the mechanism of HTL process when HTL-AP is used as a reaction medium on an industrial scale. Need to find a solution for the hindrance in commercializing HTL process and recovery of value-added compounds from HTL-AP from lab scale to industry level. Integrated pathways on reuse and HTL-AP recycle helps in reduced environmental concerns and sustainable production of bio-products.

Role of surfactant in affecting photo-fermentative bio-hydrogen production performance from corncob.

Surfactant addition can cause a significant change in the interface state of the solution system, which is helpful to avoid agglomeration and sedimentation of solid state, and improve the mass transfer capacity. Hence, the performance of high-solid photo-fermentative bio-hydrogen production system with bio-surfactant addition was evaluated in this work. Corncob was selected as raw material, and cumulative hydrogen yield (CHY) was taken as reference. The effect of Rhamnolipids (RLs) and Tea Saponin (TSn) addition on hydrogen yield capacity was investigated. The results showed that CHY was effectively increased by the addition of RLs and TSn, the highest CHY of 356.42 ± 16.5 mL and 265.38 ± 7.5 mL appeared when the concentrations of surfactant addition were 0.08 g/L RLs and 1.5 g/L TSn, which were 67.85% and 24.97% higher than control group, respectively. The maximum energy conversion efficiency reached 5.47% and 4.08% with an increase of 67.8% and 25.2%.