Potential use of thermophilic dark fermentation effluents in photofermentative hydrogen production by Rhodobacter capsulatus

Ozgur, Ebru
Afsar, Nilufer
de Vrije, Truus
Yucel, Meral
Gündüz, Ufuk
Claassen, Pieternel A. M.
Eroglu, Inci
Biological hydrogen production by a sequential operation of dark and photofermentation is a promising route to produce hydrogen. The possibility of using renewable resources, like biomass and agro-industrial wastes, provides a dual effect of sustainability in biohydrogen production and simultaneous waste removal. In this study, photofermentative hydrogen production on effluents of thermophilic dark fermentations on glucose, potato steam peels (PSP) hydrolysate and molasses was investigated in indoor, batch operated bioreactors. An extreme thermophile Caldicellulosiruptor saccharolyticus was used in the dark fermentation step, and Rhodobacter capsulatus (DSM1710) was used in the photofermentation step. Addition of buffer, Fe and Mo to dark fermentor effluents (DFEs) improved the overall efficiency of hydrogen production. The initial acetate concentration in the DFE needed to be adjusted to 30-40 mM by dilution to increase the yield of hydrogen in batch light-supported fermentations. The thermophilic DFEs are suitable for photofermentative hydrogen production, provided that they are supplemented with buffer and nutrients. The overall hydrogen yield of the two-step fermentations was higher than the yield of single step dark fermentations.


Biohydrogen production from beet molasses by sequential dark and photofermentation
Ozgur, Ebru; Mars, Astrid E.; Peksel, Beguem; Louwerse, Annemarie; Yucel, Meral; Gündüz, Ufuk; Claassen, Pieternel A. M.; Eroglu, Inci (2010-01-01)
Biological hydrogen production using renewable resources is a promising possibility to generate hydrogen in a sustainable way. In this study, a sequential dark and photofermentation has been employed for biohydrogen production using sugar beet molasses as a feedstock. An extreme thermophile Caldicellulosiruptor saccharolyticus was used for the dark fermentation, and several photosynthetic bacteria (Rhodobacter capsulatus wild type, R. capsulatus hup(-) mutant, and Rhodopseudomonas palustris) were used for t...
Photofermentative hydrogen production from molasses in tubular photobioreactor with pH control
Oflaz, Fatma Betül; Koku, Harun; Department of Chemical Engineering (2019)
Biological hydrogen production has the potential to supply hydrogen from various wastes as feedstock and operation under ambient conditions. In order to obtain cost effective production, photobioreactors (PBRs) that can operate for long durations while utilizing waste are necessary. Two primary issues limiting the duration are decrease in pH and the non-optimal C/N ratio. The main aim of this study was to construct and operate a pH control system for a pilot scale photobioreactor (20 L) to achieve prolonged...
Amelioration of photofermentative hydrogen production from molasses dark fermenter effluent by zeolite-based removal of ammonium ion
Androga, Dominic Deo; Ozgur, Ebru; EROĞLU, İNCİ; Gündüz, Ufuk; Yucel, Meral (2012-11-01)
One of the challenges in the development of integrated dark and photofermentative biological hydrogen production systems is the presence of ammonium ions in dark fermentation effluent (DFE). Ammonium strongly inhibits the sequential photofermentation process, and so its removal is required for successful process integration. In this study, the removal of ammonium ions from molasses DFE using a natural zeolite (clinoptilolite) was investigated. The samples were treated with batch suspensions of Na-form clino...
Significance of carbon to nitrogen ratio on the long-term stability of continuous photofermentative hydrogen production
Androga, Dominic Deo; Ozgur, Ebru; Eroglu, Inci; Gündüz, Ufuk; Yucel, Meral (2011-12-01)
The stable and optimized operation of photobioreactors (PBRs) is the most challenging task in photofermentative biological hydrogen production. The carbon to nitrogen ratio (C/N) in the feed is a critical parameter that significantly influences microbial growth and hydrogen production. In this study, the effects of changing the C/N ratio to achieve stable biomass and continuous hydrogen production using fed-batch cultures of Rhodobacter capsulatus YO3 (uptake hydrogenase deleted, hup-) were investigated. Th...
A compact tubular photobioreactor for outdoor hydrogen production from molasses
KAYAHAN, Emine; Eroglu, Inci; Koku, Harun (2017-01-26)
Hydrogen can be produced sustainably by photofermentation of biomass. For an economically feasible operation, the process should be implemented outdoors using low-cost organic material. In the current study, molasses from a sugar factory was utilized for photofermentative hydrogen production. The experiment was run with Rhodobacter capsulatus YO3 (hup-) in fed-batch mode under outdoor conditions in Ankara between July 12, 2015 and July 24, 2015. The stacked U-tube photobioreactor (9 L) designed for outdoor ...
Citation Formats
E. Ozgur et al., “Potential use of thermophilic dark fermentation effluents in photofermentative hydrogen production by Rhodobacter capsulatus,” JOURNAL OF CLEANER PRODUCTION, pp. 0–0, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/30300.