Table 6.
Comparison of hydrogen yields obtained in this study in continuous and batch mode with the ones reported in literature.
| Process | Operation mode | HRT (h) | Inoculum | Substrate | Zeolite | Hydrogen yielda (mmol mmol−1) | References |
|---|---|---|---|---|---|---|---|
| Dark fermentation | Continuous | 12 | Granular sludge | Glucose and arabinose (12.5 + 12.5 mM) | – | 2.33 | This study |
| 6 | – | 0.19 | |||||
| 6 | Zeolite type 13X | 0.53 | |||||
| Batch | – | Granular sludge | Glucose and arabinose (12.5 + 12.5 mM) | – | 0.53 ± 0.02 | This study | |
| – | Zeolite type 13X | 0.70 ± 0.03 | |||||
| – | Granular sludge | Sargassum sp. | – | 2.63 ± 0.03b | |||
| – | Zeolite type 13X | 3.37 ± 0.16b | |||||
| Continuous | 8 | Heat treated sludge granules | Glucose and arabinose (12.5 + 12.5 mM) | – | 0.77 ± 0.05 | 20 | |
| 10 | Granular sludge | Glucose (13.8 mM) | – | 0.80 ± 0.03 | 39 | ||
| 10 | Granular sludge | Arabinose (33.3 mM) | – | 1.10 ± 0.01 | 39 | ||
| Dark fermentation and AD | Batch | – | Caldicellulosiruptor saccharolyticus | Sargassum sp. | – | 91.30 ± 3.30c | 3 |
| Dark- and photo-fermentation | Batch | – | Heat-treated anaerobic sludge | Arthrospira platensis wet biomass | Natural zeolite | 337d | 13 |
| – | Lactobacillus delbrueckii NBRC13953 and R. sphaeroides RV | Glucose | – | 7.10 | 40 |
ammole of H2 per mmole of substrate.
bH2 produced per mass of Sargassum sp. (in VS) (mmol g−1).
cVolume of H2 produced per mass of Sargassum sp. (in VS) (L kg−1).
dVolume of H2 produced per mass of cellular dry weight (in VS) (L kg−1).
emmol of H2 produced per bioreactor culture volume per hour of operation.