|
pH 7
|
pH 6
|
---|
N2sparging ( Case I)
|
No sparging ( Case II)
|
N2sparging ( Case III)
|
No sparging ( Case IV)
|
---|
P
H2max (kPa)
|
8
|
69
|
6
|
74
|
μ
max (h-1)
|
1.09 ± 0.09
|
1.09 ± 0.08
|
0.43 ± 0.03
|
0.38 ± 0.05
|
Biomass concentration (g/l)
|
0.99 ± 0.03
|
1.13 ± 0.01
|
1.02 ± 0.03
|
1.01 ± 0.01
|
YX/ATP (gCDW/mol ATP)
|
11.5 ± 0.3
|
9.3 ± 0.1
|
6.3 ± 0.4
|
7.9 ± 0.2
|
YATP/S (mol ATP/mol glucose)
|
3.24 ± 0.03
|
3.18 ± 0.02
|
3.4 ± 0.08
|
3.48 ± 0.17
|
Q
H2 (mmol H2/l/h)
|
27.1 ± 1.5
|
33.0 ± 0.1
|
19.9 ± 0.8
|
20.6 ± 0.5
|
Product yield (mol/mol glucose)
| | | | |
YX
a
|
0.71 ± 0.01
|
0.75 ± 0.03
|
0.72 ± 0.01
|
0.75 ± 0.01
|
YH2
a
|
2.32 ± 0.13
|
2.06 ± 0.13
|
3.10 ± 0.06
|
2.60 ± 0.03
|
YA
a
|
1.24 ± 0.01
|
1.28 ± 0.01
|
1.47 ± 0.07
|
1.35 ± 0.02
|
YF
a
|
0.37 ± 0.02
|
0.71 ± 0.12
|
0.14 ± 0.07
|
0.33 ± 0.06
|
YE
a
|
0.27 ± 0.01
|
0.37 ± 0.01
|
0.10 ± 0.01
|
0.39 ± 0.03
|
RVEP
b
|
2.87 ± 0.11
|
2.8 ± 0.12
|
3.31 ± 0.08
|
3.39 ± 0.03
|
HAc/EtOH
|
4.5 ± 0.2
|
3.5 ± 0.1
|
14.2 ± 1.0
|
3.4 ± 0.3
|
Carbon recovery (%)
|
92.6 ± 0.6
|
94.0 ± 0.7
|
94.8 ± 4.2
|
100.3 ± 1.9
|
Redox recovery (%)
|
90.0 ± 0.6
|
97.5 ± 0.6
|
93.2 ± 4.1
|
102.3 ± 2.2
|
-
aY indicates the yield of product (where x=biomass, H2=hydrogen, A=acetate, F=formate and E=ethanol) per mole of glucose consumed.
-
bTotal molar reduction values of reduced end-products (RVEP = YH2 + 2 * YE) [19].