Produzione di bio-H2 da batteri rossi non-sulfurei coltivati in fotobioreattori irradiati da una o due opposte sorgenti radianti artificiali

Microbial photosynthetic process is an efficient system to convert fatty acids into bio-hydrogen and biomass, when an appropriate light source is furnished to the system. In a photobioreactor (PBR) irradiated either from one or two opposite sides, we investigated on bio-hydrogen production using Rhodopseudomonas palustris as cell-factory. Irradiating the photobioreactor over a total period of 352 h from one side, in the presence of malic acid, we achieved a reactor hydrogen production of 2.786 l(H2) PBR-1. Hydrogen photo-evolution rose to 3.162 l(H2) PBR-1 when we irradiated the PBR from two opposite sides. The PBR was also irradiated from two opposite sides using a second carbon source as acetic acid. Experiments were carried out without controlling the culture pH; it was demonstrated that the pH stabilized at 7.3 in the medium containing malic acid and at 7.6 in that containing acetic acid. The hydrogen production rate was higher with malic than with acetic acid. Moreover, the hydrogen to biomass ratio (Rp) was 1.91 l g-1 in the medium containing malic acid and 1.07 l g-1 in that containing acetic acid.