Synthesis of novel ionic liquids from lignin-derived compounds
Methods and compositions are provided for synthesizing ionic liquids from lignin. Methods and compositions are also provided for treating lignin with ionic liquids.
1. A compound selected from:
wherein two of the R groups of each nitrogen are CH 2 CH 3 ;
one of the R groups of each nitrogen is H;
R′, R″, and R′″ are independently selected from the group consisting of H, OH, and OCH 3 ;
R 4 is selected from the group consisting of H, OH, and CH 2 OH; and
X is an acid anion selected from the group consisting of acetate, dihydrogen phosphate, and hydrogen sulfate.
2. A mixture comprising at least two of the compounds of claim 1 .
3. A mixture comprising at least three of the compounds of claim 1 .
4. A mixture comprising at least four of the compounds of claim 1 .
5. A mixture comprising at least five of the compounds of claim 1 .
6. A mixture comprising at least six of the compounds of claim 1 .
7. A mixture comprising at least seven of the compounds of claim 1 .
8. A mixture comprising at least eight of the compounds of claim 1 .
9. A mixture comprising at least nine of the compounds of claim 1 .
10. A mixture comprising about 10% w/v of at least one compound of claim 1 .
11. A lignin-derived ionic liquid prepared by
contacting a starting material comprising lignin with a depolymerization agent to depolymerize the lignin and form a mixture of aldehyde containing compounds;
contacting the mixture of aldehyde containing compounds with an amine under conditions suitable to convert the mixture of aldehyde containing compounds to a mixture of amine containing compounds; and
contacting the mixture of amine containing compounds with a mineral acid under conditions suitable to form an ammonium salt, thereby preparing the lignin-derived ionic liquid,
wherein the lignin-derived ionic liquid is selected from:
wherein two the R groups of each nitrogen are CH 2 CH 3 ;
one of the R groups of each nitrogen is H;
R′, R″, and R′″ are independently selected from the group consisting of H, OH, and OCH 3 ;
R 4 is selected from the group consisting of H, OH, and CH 2 OH; and
X is an acid anion selected from the group consisting of acetate, dihydrogen phosphate, and hydrogen sulfate.
12. The ionic liquid of claim 11 , wherein the ionic liquid is a room temperature ionic liquid.
13. The ionic liquid of claim 11 , wherein the ionic liquid has a melting point at atmospheric pressure of less than about 100° C.