Ionic liquid composition and method for dissolving cellulose using the same
The present invention provides an ionic liquid composition containing an ionic liquid and water. The ionic liquid composition does not contain an enzyme capable of hydrolyzing cellulose. The ionic liquid is represented by the following chemical formula (I): [(CH 3 ) 3 N(CH 2 ) 2 OH] + [NH 2 -L-CHNH 2 —COO] − (I); where L is absent or a linker. A molar ratio of [(CH 3 ) 3 N(CH 2 ) 2 OH] + to [NH 2 -L-CHNH 2 —COO] − is not less than 0.87 and not more than 1.14. A weight ratio of the water to the ionic liquid composition is not more than 7.3%. The present invention provides an ionic liquid composition capable of dissolving cellulose without a cellulose-degrading enzyme, namely, an enzyme capable of hydrolyzing cellulose.
1. A solution in which cellulose has been dissolved in an ionic liquid composition, wherein the ionic liquid composition contains:
an ionic liquid; and
water,
wherein
the ionic liquid composition does not contain an enzyme capable of hydrolyzing cellulose;
the ionic liquid is represented by the following chemical formula (I):
[(CH 3 ) 3 N(CH 2 ) 2 OH] + [NH 2 -L-CHNH 2 —COO] − (I)
where
L is absent or a linker;
a molar ratio of [(CH 3 ) 3 N(CH 2 ) 2 OH] + to [NH 2 -L-CHNH 2 —COO] − is not less than 0.87 and not more than 1.14; and
a weight ratio of the water to the ionic liquid composition is not more than 7.3%.
2. The solution ionic liquid composition according to claim 1 , wherein
the molar ratio of [(CH 3 ) 3 N(CH 2 ) 2 OH] + to [NH 2 -L-CHNH 2 —COO] − is not less than 0.89 and not more than 1.12.
3. The solution according to claim 1 , wherein
L is —(CH 2 ) n —;
where n is a natural number.
4. The solution according to claim 3 , wherein
n is equal to 3 or 4.
5. The solution according to claim 1 , wherein
the weight ratio of the water to the ionic liquid composition is not less than 1.3%.
6. The solution according to claim 1 , wherein the ionic liquid composition further contains an aprotic polar solvent.
7. The solution according to claim 6 , wherein
the aprotic polar solvent is dimethyl sulfoxide.
8. The solution according to claim 7 , wherein
a weight ratio of the dimethyl sulfoxide to the ionic liquid is not more than 309%.
9. A method for dissolving cellulose, the method comprising:
(a) adding the cellulose to an ionic liquid composition;
wherein
the ionic liquid composition contains an ionic liquid and water;
the ionic liquid composition does not contain an enzyme capable of hydrolyzing cellulose;
the ionic liquid is represented by the following chemical formula (I):
[(CH 3 ) 3 N(CH 2 ) 2 OH] + [NH 2 -L-CHNH 2 —COO] − (I)
where
L is absent or a linker;
a molar ratio of [(CH 3 ) 3 N(CH 2 ) 2 OH] + to [NH 2 -L-CHNH 2 —COO] − is not less than 0.87 and not more than 1.14; and
a weight ratio of the water to the ionic liquid composition is not more than 7.3%.
10. The method according to claim 9 , wherein
the molar ratio of [(CH 3 ) 3 N(CH 2 ) 2 OH] + to [NH 2 -L-CHNH 2 —COO] − is not less than 0.89 and not more than 1.12.
11. The method according to claim 9 , wherein
L is —(CH 2 ) n —;
where n is a natural number.
12. The method according to claim 11 , wherein
n is equal to 3 or 4.
13. The method according to claim 9 , wherein
the weight ratio of the water to the ionic liquid composition is not less than 1.3%.
14. The method according to claim 9 , wherein the ionic liquid composition further contains
an aprotic polar solvent.
15. The method according to claim 14 , wherein
the aprotic polar solvent is dimethyl sulfoxide.
16. The method according to claim 15 , wherein
a weight ratio of the dimethyl sulfoxide to the ionic liquid is not more than 309%.
17. The method according to claim 9 , further comprising:
(b1) heating the ionic liquid composition to which the cellulose has been added to dissolve the cellulose in the ionic liquid composition after the step (a).
18. The method according to claim 9 , further comprising:
(b2) leaving the ionic liquid composition to which the cellulose has been added at rest to dissolve the cellulose in the ionic liquid composition after the step (a).
19. The method according to claim 9 , further comprising:
(b3) stirring the ionic liquid composition to which the cellulose has been added to dissolve the cellulose in the ionic liquid composition after the step (a).
20. A method for fabricating a cellulose film; the method comprising:
(a) adding cellulose to an ionic liquid composition to prepare a cellulose solution;
(b) applying the cellulose solution on a surface of a substrate to form a film on the surface;
(c) removing the ionic liquid composition from the film using a solvent; and
(d) removing the solvent from the film,
wherein
the ionic liquid composition contains an ionic liquid and water;
the ionic liquid composition does not contain an enzyme capable of hydrolyzing cellulose;
the ionic liquid is represented by the following chemical formula (I):
[(CH 3 ) 3 N(CH 2 ) 2 OH] + [NH 2 -L-CHNH 2 —COO] − (I)
where
L is absent or a linker;
a molar ratio of [(CH 3 ) 3 N(CH 2 ) 2 OH] + to [NH 2 -L-CHNH 2 —COO] − is not less than 0.87 and not more than 1.14; and
a weight ratio of the water to the ionic liquid composition is not more than 7.3%.
21. The method according to claim 20 , wherein
the molar ratio of [(CH 3 ) 3 N(CH 2 ) 2 OH] + to [NH 2 -L-CHNH 2 —COO] − is not less than 0.89 and not more than 1.12.
22. The method according to claim 20 , wherein
L is —(CH 2 ) n —;
where n is a natural number.
23. The method according to claim 22 , wherein
n is equal to 3 or 4.
24. The method according to claim 20 , wherein
the weight ratio of the water to the ionic liquid composition is not less than 1.3%.
25. The method according to claim 20 , wherein the ionic liquid composition further contains
an aprotic polar solvent.
26. The method according to claim 25 , wherein
the aprotic polar solvent is dimethyl sulfoxide.
27. The method according to claim 26 , wherein
a weight ratio of the dimethyl sulfoxide to the ionic liquid is not more than 309%.
28. A solution in which cellulose has been dissolved in an ionic liquid composition, wherein the ionic liquid is represented by the following chemical formula (I):
[(CH 3 ) 3 N(CH 2 ) 2 OH] + to [NH 2 -L-CHNH 2 —COO] − (I)
where
L is absent or a linker;
wherein a molar ratio of [(CH 3 ) 3 N(CH 2 ) 2 OH] + to [NH 2 -L-CHNH 2 —COO] − is not less than 0.87 and not more than 1.14.