title: Applications of the Box-Wilson design model for bio-hydrogen production using Clostridium saccharoperbutylacetonicum N1-4 (ATCC 13564).
abstract: Box-Wilson design (BWD) model was applied to determine the optimum values of influencing parameters in anaerobic fermentation to produce hydrogen using Clostridium saccharoperbutylacetonicum N1-4 (ATCC 13564). The main focus of the study was to find the optimal relationship between the hydrogen yield and three variables including initial substrate concentration, initial medium pH and reaction temperature. Microbial growth kinetic parameters for hydrogen production under anaerobic conditions were determined using the Monod model with incorporation of a substrate inhibition term. The values of micro(max) (maximum specific growth rate) and K, (saturation constant) were 0.398 h(-1) and 5.509 g L(-1), respectively, using glucose as the substrate. The experimental substrate and biomass-concentration profiles were in good agreement with those obtained by the kinetic-model predictions. By varying the conditions of the initial substrate concentration (1-40 g L(-1)), reaction temperature (25-40 degrees C) and initial medium pH (4-8), the model predicted a maximum hydrogen yield of 3.24 mol H2 (mol glucose)(-1). The experimental data collected utilising this design was successfully fitted to a second-order polynomial model. An optimum operating condition of 10 g L(-1) initial substrate concentration, 37 degrees C reaction temperature and 6.0 +/- 0.2 initial medium pH gave 80% of the predicted maximum yield of hydrogen where as the experimental yield obtained in this study was 77.75% exhibiting a close accuracy between estimated and experimental values. This is the first report to predict bio-hydrogen yield by applying Box-Wilson Design in anaerobic fermentation while optimizing the effects of environmental factors prevailing there by investigating the effects of environmental factors.
authors.affiliation: Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Malaysia.
authors.forename: W M
authors.initials: WM
authors.lastname: Alalayah
authors.forename: M S
authors.initials: MS
authors.lastname: Kalil
authors.forename: A A H
authors.initials: AA
authors.lastname: Kadhum
authors.forename: J
authors.initials: J
authors.lastname: Jahim
authors.forename: A
authors.initials: A
authors.lastname: Zaharim
authors.forename: N M
authors.initials: NM
authors.lastname: Alauj
authors.forename: A
authors.initials: A
authors.lastname: El-Shafie
mesh_terms: D000693:Anaerobiosis; D001671:Biochemistry / Q000379:methods; D018533:Biomass; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods; D002138:Calibration; D003013:Clostridium / Q000378:metabolism*; D003246:Conservation of Energy Resources; D003470:Culture Media / Q000737:chemistry; D005285:Fermentation; D006859:Hydrogen / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008956:Models, Chemical; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D003470:Culture Media; D006859:Hydrogen