Table 2.
Effect of ILs and their mass fractions on the IL/water/K2CO3 pretreatment and IL recovery
| IL | Mass fraction (%) | Solvent pH | Lignin removal (%) | Sugar yield (%)a | IL recovery (%) |
|---|---|---|---|---|---|
| [C8mim]Cl | 50 | 10.85 | 5.37 (± 0.06) | 32.57 (± 0.96) | 98.36 (± 1.24) |
| [C6mim]Cl | 50 | 11.08 | 24.07 (± 0.84) | 36.11 (± 0.35) | 94.25 (± 0.71) |
| [C4mim]Cl | 50 | 12.31 | 43.46 (± 0.95) | 60.97 (± 1.21) | 92.77 (± 1.25) |
| [C2mim]Cl | 50 | 13.21 | 74.36 (± 1.00) | 86.25 (± 0.05) | 90.45 (± 1.12) |
| [C2mim]Cl | 10 | 11.08 | 43.10 (± 1.58) | 74.27 (± 1.20) | 70.17 (± 0.73) |
| [C2mim]Cl | 20 | 11.74 | 50.88 (± 1.23) | 76.54 (± 0.34) | 75.66 (± 0.42) |
| [C2mim]Cl | 30 | 12.29 | 58.03 (± 1.34) | 78.48 (± 0.88) | 82.23 (± 1.03) |
| [C2mim]Cl | 40 | 12.86 | 72.38 (± 1.67) | 84.99 (± 0.51) | 88.53 (± 0.69) |
| [C2mim]Cl | 60 | 14.11 | 74.86 (± 2.46) | 86.67 (± 1.23) | 94.26 (± 1.43) |
Mass fraction of K2CO3 was 2%, pretreatment temperature was 110 °C, and pretreatment time was 1 h
aEnzymatic hydrolysis time was 72 h