Abstract
This article reviews the state-of-the-art of heterotrophic photo fermentative hydrogen production, an infantile technology for wastewater treatment. Five tables were compiled from data scattered in literature, including bacteria strain, substrate, reactor design, maximum volumetric and specific production rates (ml-H2/l/h and/or ml-H2/g-VSS/h), yield as compared to stoichiometry (%), culture volume (ml), cell density (g-VSS/l), light source, and intensity (W/m2 or klux). Operational parameters discussed include light source and light intensity, pH, temperature, substrates, nitrogen source, trace metal elements, inhibitors, and reactor design, followed by a discussion on the outlook of this technology.
ACKNOWLEDGMENTS
The authors wish to thank the Hong Kong Research Grants Council for the financial support of this study (HKU 7106/04E and 7129/05E), and Ru Ying Li wishes to thank RGC for the research assistantship and HKU for the postgraduate studentship.