title: Optimization of bio-hydrogen production from biodiesel wastes by Klebsiella pneumoniae.
abstract: Biodiesel wastes containing glycerol were utilized by Klebsiella pneumoniae DSM 2026 to produce hydrogen. The optimization of medium components was performed using both Plackett-Burman and uniform design methods. Using the Plackett-Burman design, glycerol, yeast extract, NH(4)Cl, KCl and CaCl2 were found to be the most important components, which were further investigated by uniform design and second-order polynomial stepwise regression analysis. The optimized medium containing 20.4 g.L(-1) glycerol, 5.7 g.L(-1) KCl, 13.8 g.L(-1) NH(4)Cl, 1.5 g.L(-1) CaCl(2) and 3.0 g.L(-1) yeast extract resulted in 5.0-fold increased level of hydrogen (57.6 mL/50 mL medium) production compared to initial level (11.6 mL/50 mL medium) after 24 h of fermentation The optimization of fermentation condition (pH, temperature and inoculum) was also conducted. When the strain grew in the optimized medium under optimal fermentation condition in a 5-L stirred tank bioreactor for batch production, hydrogen yield and production reached 0.53 mol/mol and 117.8 mmol/L, respectively. The maximum hydrogen evolution rate was 17.8 mmol/(L.h). Furthermore, 1,3-propanediol (6.7 g.L(-1)) was also obtained from the liquid medium as a by-product.
authors.affiliation: Province Key Laboratory of Industrial Biotechnology, Hua Qiao University, Quanzhou, Fujian, PR China.
authors.forename: Fei
authors.initials: F
authors.lastname: Liu
authors.forename: Baishan
authors.initials: B
authors.lastname: Fang
mesh_terms: D019149:Bioreactors / Q000382:microbiology; D002245:Carbon Dioxide / Q000378:metabolism; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D005285:Fermentation; D005990:Glycerol / Q000378:metabolism*; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007218:Industrial Microbiology / Q000379:methods; D007711:Klebsiella pneumoniae / Q000378:metabolism*; D008954:Models, Biological; D011409:Propylene Glycols / Q000378:metabolism; D013696:Temperature
chemical_list: D011409:Propylene Glycols; D002245:Carbon Dioxide; C041787:1,3-propanediol; D006859:Hydrogen; D005990:Glycerol