Biohydrogen production by dark fermentation of wheat powder solution: Effects of C/N and C/P ratio on hydrogen yield and formation rate

Argun H., Kargi F., Kapdan F. K., Oztekin R.

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, vol.33, no.7, pp.1813-1819, 2008 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 33 Issue: 7
  • Publication Date: 2008
  • Doi Number: 10.1016/j.ijhydene.2008.01.038
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1813-1819
  • Keywords: biohydrogen, Box-Wilson experiment design, dark fermentation, wheat powder solution (WPS), C/N and C/P ratio, H-2 PRODUCTION, RHODOBACTER-SPHAEROIDES, CLOSTRIDIUM-BUTYRICUM, MIXED CULTURE, STARCH, ACETATE
  • Dokuz Eylül University Affiliated: Yes


The effects of C/N and C/P ratio on hydrogen yield and specific production rate were investigated in dark fermentation of wheat powder solution (WPS) by external addition of N and P since the wheat powder was N and P deficient. A Box-Wilson statistical experiment design approach was used. C/N ratio was varied between 20 and 200 while C/P ratio was between 50 and 1000. A quadratic response function was used to correlate the objective functions with the independent variables and the response function coefficients were determined by regression analysis. Hydrogen yield increased with increasing C/N and C/P ratios. Low nitrogen concentrations required low phosphorous contents for high hydrogen yields. A C/N ratio of 200 and C/P ratio of 1000 yielded the highest H-2 yield of 281. ml H-2 g(-1) starch at STP. SHPR also increased with increasing C/N and C/P ratios. Again the highest SHPR (98 ml H-2 g(-1) biomass h(-1) at STP) was obtained at C/N and C/P ratios of 200 and 1000, respectively. The C/N/P ratio maximizing the yield and formation rate of hydrogen was 100/0.5/0.1 (w w(-1) w(-1)). (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.