Effect of thermal pre-treatment on inoculum sludge to enhance bio-hydrogen production from alkali hydrolysed rice straw in a mesophilic anaerobic baffled reactor

In the present piece of research, hydrogen production via the photo-reforming of glycerol (a byproduct from biodiesel generation) is studied. Catalysts consisted of titania modified by Ni (0.5% by weight) obtained through deposition–precipitation or impregnation synthetic methods (labelled as Ni-0.5-DP and Ni-0.5-IMP, respectively). Reactions were performed both under UV and solar irradiation. Activity significantly improved in the presence of Ni, especially under solar irradiation. Moreover, pre-reduced solids exhibited higher catalytic activities than untreated solids, despite the “in-situ” reduction of nickel species and the elimination of surface chlorides under reaction conditions (as evidenced by XPS). It is possible that the catalyst pretreatment at 400 °C under hydrogen resulted in some strong metal–support interactions. In summary, the highest hydrogen production value (ca. 2600 micromole H2·g−1) was achieved with pre-reduced Ni-0.5-DP solid using UV light for an irradiation time of 6 h. This value represents a 15.7-fold increase as compared to Evonik P25.

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Study on Surface Pre-Treatment of FeCrAl Metallic Substrate for Hydrogen Production Catalysts

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.813.465 ◽

2013 ◽

Vol 813 ◽

pp. 465-470

Author(s):

Xiao Xiao Zhang ◽

Kun Su ◽

Fan Lin Zeng ◽

Yu Wen Zhang ◽

Qi Fei Zhang ◽

...

Keyword(s):

Hydrogen Production ◽

Supported Catalysts ◽

Element Composition ◽

Metallic Substrate ◽

Air Atmosphere ◽

Fecral Alloy ◽

Film Adhesion ◽

Metal Support ◽

Active Coating ◽

Pre Treatment

Metal supported catalysts in hydrogen production reactor has a very broad application prospect. However, the film adhesion of active coating with the metal support is the key problem which needed to be solved urgently. In this paper, FeCrAl alloy was chosen as the metallic substrate. The effects of oxidation temperature and time on the morphology, crystal phase and element composition of the metal surface were investigated by XRD, SEM and EDAX. The results show that after pre-treatment of FeCrAl Metallic Substrate,a dense transition layer of α-Al2O3 formed on the surface of the metallic support. Thus the oxidized α-Al2O3 layer and the γ-Al2O3 coating could combine together better. The optimum pre-treatment condition is at 950°C for 10h in air atmosphere.

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Hydrogen production by the anaerobic fermentation from acid hydrolyzed rice straw hydrolysate

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2011.04.142 ◽

2011 ◽

Vol 36 (21) ◽

pp. 14280-14288 ◽

Cited By ~ 53

Author(s):

Alex C.C. Chang ◽

Ying-Hsuan Tu ◽

Ming-Hsiang Huang ◽

Chyi-How Lay ◽

Chiu-Yue Lin

Keyword(s):

Hydrogen Production ◽

Rice Straw ◽

Anaerobic Fermentation ◽

Rice Straw Hydrolysate

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Enhanced bio-energy recovery in a two-stage hydrogen/methane fermentation process

Water Science & Technology ◽

10.2166/wst.2009.236 ◽

2009 ◽

Vol 59 (11) ◽

pp. 2137-2143 ◽

Cited By ~ 11

Author(s):

M. J. Lee ◽

J. H. Song ◽

S. J. Hwang

Keyword(s):

Hydrogen Production ◽

Fermentation Process ◽

Continuous Production ◽

Strong Acid ◽

Treatment Method ◽

Engineering System ◽

Production Rates ◽

Two Stage ◽

Methane Fermentation ◽

Pre Treatment

A two-stage hydrogen/methane fermentation process has emerged as a feasible engineering system to recover bio-energy from wastewater. Hydrogen-producing bacteria (HPB) generate hydrogen from readily available carbohydrates, and organic acids produced during the hydrogen fermentation step can be degraded to generate methane in the following step. Three strong acids, HCl, H2SO4, and HNO3, were tested to determine the appropriate pre-treatment method for enhanced hydrogen production. The hydrogen production rates of 230, 290, and 20 L/kg-glucose/day was observed for the sludge treated with HCl, H2SO4, and HNO3, respectively, indicating that the acid pre-treatment using either HCl or H2SO4 resulted in a significant increase in hydrogen production. The fluorescent in situ hybridization method indicated that the acid pre-treatment selectively enriched HPB including Clostridium sp. of cluster I from inoculum sludge. After hydrogen fermentation was terminated, the sludge was introduced to a methane fermentation reactor. This experiment showed methane production rates of 100, 30, and 13 L/kg-glucose/day for the sludge pre-treated with HCl, H2SO4, and HNO3, respectively, implying that both sulfate and nitrate inhibited the activity of methane-producing bacteria. Consequently, the acid pre-treatment might be a feasible option to enhance biogas recovery in the two-stage fermentation process, and HCl was selected as the optimal strong acid for the enrichment of HPB and the continuous production of methane.

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The Performance Characteristics of Anaerobic Baffled Reactor (ABR) Fermentation System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.610-613.347 ◽

2012 ◽

Vol 610-613 ◽

pp. 347-351

Author(s):

Guo Chen Zheng ◽

Zhu Jun Tian ◽

Jian Zheng Li ◽

Li Wei ◽

Ajay Kumar Jha ◽

...

Keyword(s):

Hydrogen Production ◽

Activated Sludge ◽

Production Efficiency ◽

Oxygen Demand ◽

H2 Production ◽

Anaerobic Baffled Reactor ◽

Steady Stage ◽

Start Up ◽

Acid Type ◽

H2 Yield

A anaerobic baffled reactor (ABR) with an effective volume of 28.7 L was adopted, and the hydrogen production efficiency was investigated with diluted molasses as the substrate. Using a mixture of aerobic and anaerobic activated sludge, the ABR was start-up with a hydraulic retention time (HRT) of 24 h and 35°C. When the influent chemical oxygen demand (COD) concentration was gradually increased from 500 mg/L to 6000 mg/L after a 63-day operation, the ABR kept a steady state. The increase of influent COD concentration, from 6000 mg/L to 8000 mg/L stage by stage, had the remarkable changes on the fermentative system. The ethanol-type fermentation was formed in the first three compartments, while butyric acid-type fermentation in the 4th compartment. In the steady stage at the influent COD of 8000 mg/L, the biogas (H2) yield was found 61.54 L/d (12.85 L/d) while specific H2 production rate of the activated sludge was 48 L/kgMLVSS∙d. Although the ABR system accumulated hydrogen-producing acetogen, due to the hydrogen-consuming bacteria (methanogen and homoacetogenic bacteria), the hydrogen production efficiency was badly inhibited.

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Effect of physicochemical pre-treatment of rice straw on its digestibility by Clostridium cellulolyticum

Bioprocess and Biosystems Engineering ◽

10.1007/s00449-016-1652-3 ◽

2016 ◽

Vol 39 (11) ◽

pp. 1775-1784 ◽

Cited By ~ 1

Author(s):

Metinee Wasoontharawat ◽

Sirima Suvarnakuta Jantama ◽

Sunthorn Kanchanatawee ◽

Kaemwich Jantama

Keyword(s):

Rice Straw ◽

Clostridium Cellulolyticum ◽

Pre Treatment

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Heat Pre-Treatment of Beverages Wastewater on Hydrogen Production

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/210/1/012023 ◽

2017 ◽

Vol 210 ◽

pp. 012023 ◽

Cited By ~ 1

Author(s):

S Z Uyub ◽

N S Mohd ◽

S Ibrahim

Keyword(s):

Hydrogen Production ◽

Pre Treatment

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Assessment of Photocatalytic Hydrogen Production from Biomass or Wastewaters Depending on the Metal Co-Catalyst and Its Deposition Method on TiO2

Catalysts ◽

10.3390/catal9070584 ◽

2019 ◽

Vol 9 (7) ◽

pp. 584 ◽

Cited By ~ 11

Author(s):

Mikel Imizcoz ◽

Alberto V. Puga

Keyword(s):

Hydrogen Production ◽

Noble Metals ◽

Treatment Method ◽

H2 Production ◽

Catalyst Loading ◽

Co Catalyst ◽

Photocatalytic Hydrogen Production ◽

Loading Method ◽

Pre Treatment ◽

Loading Methods

A systematic study on the solar photocatalytic hydrogen production (photoreforming) performance of M/TiO2 (M = Au, Ag, Cu or Pt) using glucose as a model substrate, and further extended to lignocellulose hydrolysates and wastewaters, is herein presented. Three metal (M) co-catalyst loading methods were tested. Variation of the type of metal results in significantly dissimilar H2 production rates, albeit the loading method exerts an even greater effect in most cases. Deposition-precipitation (followed by hydrogenation) or photodeposition provided better results than classical impregnation (followed by calcination). Interestingly, copper as a co-catalyst performed satisfactorily as compared to Au, and slightly below Pt, thus representing a realistic inexpensive alternative to noble metals. Hydrolysates of either α-cellulose or rice husks, obtained under mild conditions (short thermal cycles at 160 °C), were rich in saccharides and thus suitable as feedstocks. Nonetheless, the presence of inhibiting byproducts hindered H2 production. A novel photocatalytic UV pre-treatment method was successful to initially remove the most recalcitrant portion of these minor products along with H2 production (17 µmol gcat−1 h−1 on Cu/TiO2). After a short UV step, simulated sunlight photoreforming was orders of magnitude more efficient than without the pre-treatment. Hydrogen production was also directly tested on two different wastewater streams, that is, a municipal influent and samples from operations in a fruit juice producing plant, with remarkable results obtained for the latter (up to 115 µmol gcat−1 h−1 using Au/TiO2).

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