Table 3 Pretreatment conditions, efficiency, and results of different ketone organosolv pretreatment systems

Acetone

Barley straw

50% w/w

1:20

140

20 min

–

66.7% high total xylose recovery, 75.4% enzymatic digestibility

(Salapa et al. 2018)

Pinus radiata D. Don

50% w/w

1:7

183–197

4–46 min

–

Solid recoveries of 54.6% (70.9% glucan), 40% (46.3% glucan) and 36 g/L (99.5%) ethanol productivity

(Araque et al. 2008)

Mustard

80%

1:10

121

90 min

H₂SO₄

32.9% lignin reduction and 13.67% maximum glucose yield

(Singh et al. 2021)

Wheat straw

50% w/w aqueous acetone

1:10

140

120 min

H₂SO₄

96.8 wt% C5 sugar recovery and 91.4 wt% C6 sugar recovery 79.1 wt% delignification

(Smit & Huijgen 2017)

Hardwood (birch)

50% w/w

1:5

140

120 min

H₂SO₄

87.7 wt% C6 recovery, 92.0 wt% C5 recovery, 86.4 wt% delignification

Softwood (pine)

50% w/w

1:5

140

120 min

H₂SO₄

74.2 wt% C6 recovery, 88.6 wt% C5 recovery, 31.6 wt% delignification

Methyl isobutyl ketone–acetone–water

Corn stover

–

–

140

56 min

H₂SO₄

Cellulose-enriched fraction contained 88%

Glucan content, lignin enriched fraction contained 85% lignin content

(Katahira et al. 2014)

Sugarcane bagasse

–

1:40

180

15–60 min

Acidic ionic liquid catalyst

Highest conversion of bagasse (85.8–92.7%) and the 76.3% lignin extraction ratio

(Teng et al. 2016)