Abstract: A polymer-nanocellulose-lignin composite as disclosed comprises a polymer, nanocellulose, and lignin, wherein lignin forms a hydrophobic interface between the polymer and the nanocellulose.

Abstract: A polymer-nanocellulose-lignin composite as disclosed comprises a polymer, nanocellulose, and lignin, wherein lignin forms a hydrophobic interface between the polymer and the nanocellulose.

Abstract: 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.

Abstract: A polymer-nanocellulose-lignin composite as disclosed comprises a polymer, nanocellulose, and lignin, wherein lignin forms a hydrophobic interface between the polymer and the nanocellulose.

Abstract: Processes are described for fractionating lignocellulosic biomass into cellulose, hemicellulose, and lignin, comprising fractionating lignocellulosic biomass in the presence of a solvent for lignin (such as ethanol), a hydrolysis catalyst (such as sulfur dioxide), and water, to produce a liquor containing hemicellulose, cellulose-rich solids, and lignin; hydrolyzing the hemicellulose to produce hemicellulosic monomers; saccharifying the cellulose-rich solids to produce glucose; recovering the hemicellulosic monomers and the glucose, separately or in a combined stream, as fermentable sugars; and fermenting the fermentable sugars to a fermentation product having a higher normal boiling point than water. Process integration of mass and/or energy is disclosed in many specific embodiments. The fermentation product may include an organic acid, an alcohol, a diol, or combinations thereof.

Abstract: The disclosed invention is a modification of the AVAP® technology, employing CO2 (or derivatives thereof) rather than SO2 in the cooking liquor. In some variations, the invention provides a process for fractionating cellulosic biomass into cellulose, hemicellulose, and lignin, comprising: fractionating the feedstock in the presence of a solvent for lignin, carbon dioxide, and water, to produce a liquor containing hemicellulose, cellulose-rich solids, and lignin; substantially removing the cellulose-rich solids from the liquor; hydrolyzing the hemicellulose contained in the liquor, to produce hemicellulosic monomers; hydrolyzing at least some of the cellulose-rich solids to produce glucose (or recovering the cellulose-rich solids as a cellulose product); recovering the hemicellulosic monomers to produce fermentable sugars; and recovering the lignin which may be in the form of a lignocarbonate.

Abstract: The invention herein is an efficient, flexible biomass fractionation process comprising digesting a lignocellulosic-biomass material at about 120-220° C. and a pH of less than about 4, in an aqueous mixture containing an effective concentration of at least one solvent for lignin, and separating to recover a solid phase that contains a large fraction of the cellulose originally in the starting lignocellulosic material and a liquid phase that contains most of the lignin and hemicellulose originally in the starting lignocellulosic biomass. The process can produce a solid phase that contains at least 75% cellulose and less than 10% lignin. The cellulose-rich solid product can be converted very efficiently to glucose. The solid product can also be used in commercial pulp applications, such as papermaking or fluff pulp. Hemicellulose sugars and lignin can be used directly or converted to other products.