PROLONGED EVOLUTION OF PHOTOHYDROGEN BY INTERMITTENT SUPPLY OF NITROGEN USING A COMBINED SYSTEM OF PHORMIDIUM-VALDERIANUM, HALOBACTERIUM-HALOBIUM, AND ESCHERICHIA-COLI

Continuous and stable hydrogen production was achieved by immobilizing the combined system of Phormidium valderianum, Halobacterium halobium , and Escherichia coli in a PVA-alginate film. The intermittent supply of nitrogen was found to be essential to retain cellular metabolic ac tivities which in turn showed prolonged production of hydrogen. The su pply of combined nitrogen was optimized and hydrogen production contin ued for more than four months. (C) 1998 International Association for Hydrogen Energy.