- Biomass pretreatment for biofuel production
- Product separation and recovery
- Paper pulping
- Other industries using ionic liquids, e.g., pharmaceutical, industrial chemical and polymer manufacturing; lithium ion battery additives; and specialty cleaning, among others
- Facilitates cost effective use of ionic liquids for biomass pretreatment
- Enables commercially viable ionic liquid biorefineries
- Creates ionic liquids from a renewable source
Researchers at the Joint BioEnergy Institute (JBEI) have developed a technology to convert chemicals derived from lignin into ionic liquids for use in biomass pretreatment and other industrial applications in which ionic liquids are used as solvents or co-solvents. Using the JBEI technology, lignin is depolymerized into targeted monolignols. These monolignols are converted into ionic liquids by way of reductive amination of monolignol aldehydes with secondary amines to produce tertiary amines that can be converted to ionic liquids by treatment with appropriate acids.
Using lignocellulosic biomass to produce sugars leaves a product stream consisting mainly of lignin. Therefore, this invention provides a low cost feedstock for ionic liquid production and a simple, inexpensive method of producing ions suitable for ionic liquid synthesis at temperatures including room temperature (RTIL). This approach is also applicable in the pulp and paper industry, where large amounts of lignin are generated.
Biomass pretreatment with ionic liquids increases yields of sugar monomers. However, most of the ionic liquids used to date are manufactured from cations that require elaborate synthetic and purification methods, raising their cost and necessitating the need for almost 100% recovery across the biomass pretreatment process. The cost effective generation of an RTIL from lignin addresses these obstacles. In addition, the JBEI technology could be developed to generate a suite of ionic species in one pot from mixtures of monolignols rather than with purified molecular entities.
DEVELOPMENT STAGE: Ongoing testing and development. Researchers were able to generate four new RTILs using the technology’s reductive amination process followed by salt metathesis reactions. These RTILs are capable of solubilizing a significant amount of lignin and are being used in the pretreatment of lignocellulose.
STATUS: Patent pending. Available for licensing or collaborative research.
REFERENCE NUMBER: EIO-2013-042
The Joint BioEnergy Institute (JBEI, www.jbei.org) is a scientific partnership led by the Lawrence Berkeley National Laboratory and including the Sandia National Laboratories, the University of California campuses of Berkeley and Davis, the Carnegie Institution for Science and the Lawrence Livermore National Laboratory. JBEI’s primary scientific mission is to advance the development of the next generation of biofuels.