REFINING CELLULOSE IN A SOLVENT FOR PRODUCTION OF NANOCELLULOSE MATERIALS

摘要

Cellulose precursor materials may be refined (e.g., fibrillated) in an ethanol medium, or other solvent medium, instead of water. Following refining, the solvent may be removed and recycled prior to incorporation into another material, or optionally, following such incorporation. The solvent may assist the incorporation of nanocellulose into another material (e.g., a polymer) for a composite, for example. In some variations, a process comprises fractionating a biomass feedstock in the presence of an acid, a solvent for lignin, and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; mechanically treating the cellulose-rich solids, in the presence of a refining solvent, to form cellulose fibrils and/or cellulose crystals, thereby generating a nanocellulose material; recovering and recycling the refining solvent; and recovering the nanocellulose material or incorporating the nanocellulose material into a composite material.