title: Effective conversion of maize straw wastes into bio-hydrogen by two-stage process integrating H2 fermentation and MECs.
abstract: The enhanced H2 production from maize straw had been achieved through the two-stage process of integrating H2 fermentation and microbial electrolysis cells (MECs) in the present work. Several key parameters affecting hydrolysis of maize straw through subcritical H2O were optimized by orthogonal design for saccharification of maize straw followed by H2 production through H2 fermentation. The maximum reducing sugar (RS) content of maize straw reached 469.7 mg/g-TS under the optimal hydrolysis condition with subcritical H2O combining with dilute HCl of 0.3% at 230 °C. The maximum H2 yield, H2 production rate, and H2 content was 115.1 mL/g-TVS, 2.6 mL/g-TVS/h, and 48.9% by H2 fermentation, respectively. In addition, the effluent from H2 fermentation was used as feedstock of MECs for additional H2 production. The maximum H2 yield of 1060 mL/g-COD appeared at an applied voltage of 0.8 V, and total COD removal reached about 35%. The overall H2 yield from maize straw reached 318.5 mL/g-TVS through two-stage processes. The structural characterization of maize straw was also carefully investigated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) spectra.
authors.affiliation: College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, 450052, People's Republic of China.
authors.forename: Yan-Hong
authors.initials: YH
authors.lastname: Li
authors.affiliation: College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, 450052, People's Republic of China.
authors.forename: Yan-Xia
authors.initials: YX
authors.lastname: Bai
authors.affiliation: Biotechnology Department, Henan University of Animal Husbandry and Economy, Zhengzhou, 450011, People's Republic of China. pancm7570@163.com.
authors.forename: Chun-Mei
authors.initials: CM
authors.lastname: Pan
authors.affiliation: College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, 450052, People's Republic of China.
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Li
authors.affiliation: College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, 450052, People's Republic of China.
authors.forename: Hui-Qin
authors.initials: HQ
authors.lastname: Zheng
authors.affiliation: College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, 450052, People's Republic of China.
authors.forename: Jing-Nan
authors.initials: JN
authors.lastname: Zhang
authors.affiliation: College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, 450052, People's Republic of China. yt.fan@zzu.edu.cn.
authors.forename: Yao-Ting
authors.initials: YT
authors.lastname: Fan
authors.affiliation: College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, 450052, People's Republic of China.
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Hou
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D004572:Electrolysis; D005285:Fermentation; D006859:Hydrogen / Q000737:chemistry / Q000378:metabolism*; D006868:Hydrolysis; D007218:Industrial Microbiology; D018547:Plant Stems / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*; D014866:Waste Products / Q000032:analysis; D014961:X-Ray Diffraction; D003313:Zea mays / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*
chemical_list: D014866:Waste Products; D006859:Hydrogen
keywords: Bio-hydrogen production; Hydrogen fermentation; Maize straw; Microbial electrolysis cells (MECs); Subcritical water hydrolysis