Table 2 Performance of CH3OH production in different types of membrane bioreactors
Refs. | Bacteria strain | Reactor type | Operation | Total production period (h) | MDH inhibition method | External reducing agent | CH3OH productivity (mmol L−1 h−1) | Conversion (%) |
|---|---|---|---|---|---|---|---|---|
This study | Methylococcus capsulatus Bath | Inverse membrane bioreactor | Gas: continuous supply at 0.2 mL min−1 (CH4:air = 1: 4 v/v) Aqueous: continuous supply at 4 mL h−1 Reaction volume: 5 mL | 76 | 10 μM Cyclopropanol | 10 mM sodium formate | 0.88 | Max: 37a Steady state: 27b |
This study | Methylococcus capsulatus Bath | Inverse membrane bioreactor | Gas: continuous supply at 3 mL min−1 (CH4:air = 1: 4 v/v) Aqueous: batch Reaction volume: 5 mL | 6 | 10 μM Cyclopropanol | 10 mM sodium formate | 0.62 | Max: 60c Overall: 24d |
Duan et al. (2011) [34] | Methylosinus trichosporium OB3b | Bubble free membrane bioreactor | Gas: continuous supply at 112 mL min−1 (CH4:O2 = 1: 1 v/v) Aqueous: batch Reaction volume: 300 mL | 40 | 400 mM phosphate 10 mM MgCl2 | 20 mM sodium formate | 0.74 | 64 |
Pen et al. (2014) [33] | Methylosinus trichosporium OB3b | Batch membrane bioreactor | Gas: continuous supply at 94 mL min−1 (CH4:O2 = 1: 1 v/v) Aqueous: Batch Reaction volume: 50 mL | 24 | 12.9 mM phosphate 100 mM NaCl 1.0 mM EDTA | 20 mM sodium formate | 0.38 | N/D |
Pen et al. (2016) [36] | Methylosinus trichosporium OB3b | Fed-batch membrane bioreactor | Gas: continuous supply at 94 mL min−1 (CH4:O2 = 1: 1 v/v) Aqueous: semi-batch Reaction volume: 150 mL | 48 | 12.9 mM phosphate 100 mM NaCl 1.0 mM EDTA | 20 mM sodium formate | 8.15 × 10–2 | N/D |
Xin et al. (2004) [35] | Methylosinus trichosporium IMV 3011 | Continuous stirred membrane reactor | Gas: continuous supply at 5 mL min−1 (CH4:O2:N2: CO2  = 1:1:1:2 v/v) Aqueous: continuous supply at 7 mL h−1 Reaction volume: 40 mL | 198 | Carbon dioxide | Partial CH3OH oxidation for NADH regeneration | 2.90 × 10–3 | N/D |