- Ionic liquid manufacturing
- Potential to reduce capital costs of lignocellulosic biorefineries
- Improves ability to create high-valued ionic liquids from biomass
Researchers led by Blake Simmons and Seema Singh at the Joint BioEnergy Institute (JBEI) have demonstrated that mucic acid – the aldaric acid of galactose – can form an ionic liquid (IL) effective at pretreating lignocellulosic biomass, when paired with a choline cation.
Typically, ILs used for biomass pretreatment are manufactured from non-lignocellulosic carbon sources, adding extra capital costs to a lignocellulosic biorefinery. To lower costs, attempts have been made to generate ILs from lignocellulosic feedstocks, which are inexpensive and could be produced onsite at a lignocellulosic biorefinery. One method to do this is to convert monomeric sugars into ionic liquid anions and cations. These sugars can be derived from lignocellulosic biomass hydrolysates rich in glucose and xylose or from any other sugar present in biomass, such as galactose, arabinose, mannose, etc. To generate anions, the sugars can be chemically or enzymatically converted to their uronic, aldonic, or aldaric acid form. These anions can be paired with other non-sugar derived IL cations, such as choline or 1-ethyl-3-methylimidazolium, or with sugar cations generated by forming positively charged salts, using processes such as amination.
STATUS: Patent pending. Available for licensing or collaborative research
DEVELOPMENT STAGE: A 36 wt. % choline:mucic acid IL generated from a mixture of choline hydroxide and mucic acid titrated to a pH of 13 was used to pretreat switchgrass at 140°C for 1 hour. Then, the pH was adjusted to pH 5 and the IL concentration to 20%. This slurry was then enzymatically hydrolyzed with a commercial cellulase cocktail at 10mgEP/g glucan and liberated 76% glucose and 49% xylose-based ionic liquid.
REFERENCE NUMBER: 2015-059