Table 3 Results of fed-batch fermentation in biofilm reactors coupled with fixed-bed adsorption

Fermentation time (h)

57

64

135

Glucose fermented (g/L)

198

297

367

Resin used (g)

418

812

910

Adsorbed ethanol (g)

1.8

0.82

2.2

Adsorbed acetone (g)

12.3

35.7

23.6

Adsorbed butanol (g)

42.1

68.1

84.7

Adsorbed acetoin (g)

0.40

2.4

1.2

Adsorbed butyrate (g)

1.9

3.1

8.7

Equivalent ethanol concentration (g/L)

5.1

4.8

6.8

Equivalent acetone concentration (g/L)

14.8

30.9

28.8

Equivalent butanol concentration (g/L)

38.2

58.3

92.6

Equivalent acetoin concentration (g/L)

1.7

2.6

2.6

Equivalent butyrate concentration (g/L)

1.7

2.4

10.8

^aSolvent concentration (g/L)

59.8

96.5

130.7

^aSolvent productivity (g · L^-1 · h^-1)

1.05

1.51

0.97

^aSolvent yield (g/g)

0.302

0.325

0.356

^bTotal product yield (g/g)

0.311

0.333

0.386

Butanol-acetone molar ratio

2.6^c

1.9

3.2