Hydrogen generation by Rhodobacter spahaeroides O.U. 001: the effect of photobioreactor construction material

Genertation of hydrogen by purple, non-sulfur bacteria of Rhodobacter sphaeroides O.U.001 was tested in photobioreactors made of different materials. Reactors made of ordinary sodium-type glass, borosilicate glass (Pyrex) or polycarbonate were applied in the present study. The applied medium containing malic acid and sodium glutamate inoculated with 0.11 or 0.31 g dry wt. of Rhodobacater sphaeroides was illuminated with 5 or 17 klx. Simultanous measurements of evolved hydrogen, biomass growth, and COD were performed. The concentration of carotenoides and bacteriochlorophyll was tested. In all tests the highest yield of hydrogen was obtained applying sodium glass photobioreactors illuminated with of 5 klx. Application of borosilicate glass or polycarbonate reactors reduced the amount of evolved hydrogen by 75 %. The best yield of hydrogen (2.1 dm 3 of H2 per dm 3 of medium) was obtained after illumination with 5 klx.