Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Bilimleri Enstitüsü, Fen Bilimleri Enstitüsü, Türkiye
Tezin Onay Tarihi: 2011
Öğrenci: ENDAM ÖZKAN
Danışman: UFUK GÜNDÜZ
Özet:Biological hydrogen production through integration of dark and photo-fermentation by using biomass is a promising alternative for energy supply problems. The main purpose of this study was to investigate photobiological H2 production by the purple non-sulfur (PNS) bacteria Rb. capsulatus on dark fermentation effluent of sugar beet thick juice (DFESBTJ). Presence of NH4+ in effluents is an important parameter since NH4+ inhibit the nitrogenase enzyme activity. Therefore, the influence of different NH4+ concentrations in the DFESBTJ by removing using natural zeolite clinoptilolite on photofermentative H2 production were studied using Rb. capsulatus DSM1710 and Rb. capsulatus YO3 (hup-). Also, the effect of EtOH concentrations (between 6.25 and 200 mM) in the defined medium on H2 production were studied using both bacterial strains since EtOH is a possible by-product of dark fermentation process. The experiments were carried out in small scale bottle photobioreactors (PBRs) and outdoor panel PBR (4 L). H2 productivity of 1.12 mmol/Lc/h was attained over 15 days of operation for panel PBR. The results showed that the zeolite was effective in removing NH4+ from the DFESBTJ as its concentration decreased by 95% after treatment. In both bacterial strains, an increase in the maximum productivities and molar H2 yields was observed with the decrease in NH4+concentrations. There was no significant effect of EtOH on H2 production except the inhibition at 200 mM. The main conclusions were that both bacterial strains could effectively utilize the DFESBTJ for growth and H2 production, therefore facilitating the integration of the dark and photo-fermentation for sustainable biohydrogen production.