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 low-cost process is provided to render lignocellulosic biomass accessible to cellulase enzymes, to produce fermentable sugars. Some variations provide a process to produce ethanol from lignocellulosic biomass (such as sugarcane bagasse or corn stover), comprising introducing a lignocellulosic biomass feedstock to a single-stage digestor; exposing the feedstock to a reaction solution comprising steam or liquid hot water within the digestor, to solubilize the hemicellulose in a liquid phase and to provide a cellulose-rich solid phase; refining the cellulose-rich solid phase, together with the liquid phase, in a mechanical refiner, thereby providing a mixture of refined cellulose-rich solids and the liquid phase; enzymatically hydrolyzing the mixture in a hydrolysis reactor with cellulase enzymes, to generate fermentable sugars; and fermenting the fermentable sugars to produce ethanol. Many alternative process configurations are described.

Abstract: An oleophilic and hydrophobic nanocellulose material is disclosed herein, for nanocellulose sponges and other applications. The oleophilic and hydrophobic nanocellulose material comprises lignin-coated cellulose nanofibrils and/or lignin-coated cellulose nanocrystals. In various embodiments, the nanocellulose material is in the form of a 2D coating or layer, or a 3D object (e.g., foam or aerogel). The nanocellulose material may be disposed onto a scaffold.

Abstract: A method of enzymatically hydrolyzing pretreated lignocellulosic biomass at high solids concentration includes introducing pretreated biomass to a hydrolysis reactor, to hydrolyze the cellulose to glucose monomer and glucose oligomers, and circulating a liquid stream, from which glucose is removed to reduce glucose inhibition of cellulose hydrolysis. A surfactant may be added to the hydrolysis reactor. Heat and/or acid treatment of the glucose oligomers may be used to generate additional glucose monomer. Some variations introduce pretreated biomass to a hydrolysis reactor to hydrolyze cellulose to glucose monomer and glucose oligomers, followed by conveying a portion of the solid phase to a mechanical refiner and/or a unit under reduced pressure, to generate a refined and/or exploded solid phase; and recycling the refined and/or exploded solid phase, optionally reheated, back to an input of the hydrolysis reactor.

Abstract: Processes disclosed are capable of converting biomass into high-crystallinity nanocellulose with surprisingly low mechanical energy input. In some variations, the process includes fractionating biomass with an acid (such as sulfur dioxide), a solvent (such as ethanol), and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; and mechanically treating the cellulose-rich solids to form nanofibrils and/or nanocrystals. The crystallinity of the nanocellulose material may be 80% or higher, translating into good reinforcing properties for composites. The nanocellulose material may include nanofibrillated cellulose, nanocrystalline cellulose, or both. In some embodiments, the nanocellulose material is hydrophobic via deposition of some lignin onto the cellulose surface. Optionally, sugars derived from amorphous cellulose and hemicellulose may be separately fermented, such as to monomers for various polymers.

Abstract: A composition comprising nanocellulose is disclosed, wherein the nanocellulose contains very low or essentially no sulfur content. The nanocellulose may be in the form of cellulose nanocrystals, cellulose nanofibrils, or both. The nanocellulose is characterized by a crystallinity of at least 80%, an onset of thermal decomposition of 300° F. or higher, and a low light transmittance over the range 400-700 nm. Other variations provide a composition comprising lignin-coated hydrophobic nanocellulose, wherein the nanocellulose contains very low or essentially no sulfur content. Some variations provide a composition comprising nanocellulose, wherein the nanocellulose contains about 0.1 wt % equivalent sulfur content, or less, as SO4 groups chemically or physically bound to the nanocellulose. In some embodiments, the nanocellulose contains essentially no hydrogen atoms (apart from hydrogen structurally contained in nanocellulose itself) bound to the nanocellulose.

Abstract: Some variations provide a new nanolignocellulose composition comprising, on a bone-dry, ash-free, and acetyl-free basis, from 35 wt % to 80 wt % cellulose nanofibrils, cellulose microfibrils, or a combination thereof, from 15 wt % to 45 wt % lignin, and from 5 wt % to 20 wt % hemicelluloses. The hemicelluloses may contain xylan or mannan as the major component. Novel properties arise from the hemicellulose content that is intermediate between high hemicellulose content of raw biomass and low hemicellulose content of conventional nanocellulose. The nanolignocellulose composition is hydrophobic due to the presence of lignin. Processes for making and using the nanolignocellulose compositions are also described.

Abstract: Processes disclosed are capable of converting biomass into high-crystallinity nanocellulose with surprisingly low mechanical energy input. In some variations, the process includes fractionating biomass with an acid (such as sulfur dioxide), a solvent (such as ethanol), and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; and mechanically treating the cellulose-rich solids to form nanofibrils and/or nanocrystals. The crystallinity of the nanocellulose material may be 80% or higher, translating into good reinforcing properties for composites. The nanocellulose material may include nanofibrillated cellulose, nanocrystalline cellulose, or both. In some embodiments, the nanocellulose material is hydrophobic via deposition of some lignin onto the cellulose surface. Optionally, sugars derived from amorphous cellulose and hemicellulose may be separately fermented, such as to monomers for various polymers.

Abstract: This disclosure provides lignin-based enzymatic hydrolysis enhancer that includes ethanol-soluble, partially sulfonated lignin. Some embodiments provide a lignin-based enzymatic hydrolysis enhancer comprising AVAP® lignin. Certain embodiments provide a lignin-based enzymatic hydrolysis enhancer comprising AVAP® lignin and lignosulfonates. In some variations, a process for producing a lignin-based enzymatic hydrolysis enhancer comprises fractionating biomass with an acid, a solvent for lignin, and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; recovering the lignin; and generating a lignin-based enzymatic hydrolysis enhancer comprising the lignin. Surprisingly, the lignin-based enzymatic hydrolysis enhancer is experimentally able to enhance glucose yields by 10% or more.

Abstract: Some variations provide a process for producing a nanocellulose material, comprising: providing a biomass feedstock comprising a bleached or unbleached pulp material; fractionating the 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; and mechanically treating the cellulose-rich solids to form cellulose fibrils and/or cellulose crystals, thereby generating a nanocellulose material. The process is preferably co-located with, or adjacent to, a mill that generates the pulp material. There are several advantages of a bolt-on AVAP® nanocellulose plant to an existing pulp mill, as disclosed herein.

Abstract: A low-cost process is provided to render lignocellulosic biomass accessible to cellulase enzymes, to produce fermentable sugars. Some variations provide a process to produce ethanol from lignocellulosic biomass (such as sugarcane bagasse or corn stover), comprising introducing a lignocellulosic biomass feedstock to a single-stage digestor; exposing the feedstock to a reaction solution comprising steam or liquid hot water within the digestor, to solubilize the hemicellulose in a liquid phase and to provide a cellulose-rich solid phase; refining the cellulose-rich solid phase, together with the liquid phase, in a mechanical refiner, thereby providing a mixture of refined cellulose-rich solids and the liquid phase; enzymatically hydrolyzing the mixture in a hydrolysis reactor with cellulase enzymes, to generate fermentable sugars; and fermenting the fermentable sugars to produce ethanol. Many alternative process configurations are described.

Abstract: Nanocellulose-reinforced cellulose fibers can increase the strength of hardwood fibers or agricultural-residue cellulose fibers, to simulate the strength of softwood fibers in pulp or pulp products (including composites). In some variations, the invention provides a method of reinforcing cellulose fibers, comprising providing cellulose fibers derived from hardwoods, agricultural residues, or a combination thereof; providing a source of nanocellulose comprising cellulose nanofibrils and/or cellulose nanocrystals; and reinforcing the cellulose fibers with the nanocellulose to increase strength of the cellulose fibers. In some embodiments, the nanocellulose is obtained from fractionating biomass in the presence of an acid, a solvent for lignin, and water, to generate cellulose-rich solids and a liquid phase; and then mechanically refining the cellulose-rich solids to generate the nanocellulose.

Abstract: The present invention provides a process for producing a nanocellulose material, comprising: fractionating a lignocellulosic biomass feedstock in the presence of a solvent for lignin and water, but no acid catalyst, to generate cellulose-rich solids; and then mechanically treating the cellulose-rich solids to form a nanocellulose material comprising cellulose nanofibrils and/or cellulose nanocrystals. Many organic or inorganic solvents are possible. In some embodiments, the solvent for lignin is an oxygenated organic compound, such as a C1-C18 alcohol, e.g. ethanol, ethylene glycol, propanol, propanediol, glycerol, butanol, or butanediol. The solvent for lignin may be an aromatic alcohol, such as phenol, cresol, or benzyl alcohol. The solvent for lignin may be a ketone, an aldehyde, or an ether, such as methyl ethyl ketone or diethyl ether. The solvent for lignin may be a non-oxygenated alkane, olefin, or aromatic hydrocarbon. In some embodiments, the solvent for lignin is an ionic liquid.

Abstract: In some variations, a process is provided for producing a pulp product at a biorefinery site, comprising: converting a woody cellulosic material to a first pulp stream; converting a non-woody cellulosic material to a second pulp stream; blending the second pulp stream into the first pulp stream; and recovering or further processing the blended pulp stream as a pulp product. Biorefinery site infrastructure may be shared between the woody and non-woody lines. Also, the process may include process integration of mass and/or energy between the woody and non-woody lines. The process may be a retrofit addition to a pulp plant, or a greenfield biorefinery site. The non-woody line also can generate fermentable sugars, for fermentation to ethanol (or other products). Through allocation of carbon credits from the ethanol to the pulp, the final pulp product life-cycle profile can be improved.

Abstract: In some variations, OCC is screened, cleaned, deinked, and mechanically refined to generate cellulose nanofibrils. The OCC may be subjected to further chemical, physical, or thermal processing, prior to mechanical refining. For example, the OCC may be subjected to hot-water extraction, or fractionation with an acid catalyst, a solvent for lignin, and water. In certain embodiments to produce cellulose nanocrystals, OCC is exposed to AVAP® digestor conditions. The resulting pulp is optionally bleached and is mechanically refined to generate cellulose nanocrystals. In certain embodiments to produce cellulose nanofibrils, OCC is exposed to GreenBox+® digestor conditions. The resulting pulp is mechanically refined to generate cellulose nanofibrils. The site of a system to convert OCC to nanocellulose may be co-located with an existing OCC processing site. The nanocellulose line may be a bolt-on retrofit system to existing infrastructure.

Abstract: Processes disclosed are capable of converting biomass into high-crystallinity, hydrophobic cellulose. In some variations, the process includes fractionating biomass with an acid (such as sulfur dioxide), a solvent (such as ethanol), and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; and depositing lignin onto cellulose fibers to produce lignin-coated cellulose materials (such as dissolving pulp). The crystallinity of the cellulose material may be 80% or higher, translating into good reinforcing properties for composites. Optionally, sugars derived from amorphous cellulose and hemicellulose may be separately fermented, such as to monomers for various polymers. These polymers may be combined with the hydrophobic cellulose to form completely renewable composites.

Abstract: The present invention provides a pulp product (e.g., paper) comprising cellulose and nanocellulose, wherein the nanocellulose is derived from the cellulose in a mechanical and/or chemical step that is separate from the main pulping process. The pulping process may be thermomechanical pulping or hydrothermal-mechanical pulping, for example. The pulp product is stronger and smoother with the presence of the nanocellulose. The nanocellulose further can function as a retention aid, for a step of forming the pulp product (e.g., in a paper machine). Other embodiments provide a corrugated medium pulp composition comprising cellulose pulp and nanocellulose, wherein the nanocellulose includes cellulose nanofibrils and/or cellulose nanocrystals and the nanocellulose may be hydrophobic. The nanocellulose improves the strength properties of the corrugated medium. In some embodiments, the cellulose pulp is a GreenBox+® pulp and the nanocellulose is derived from the AVAP® process.

Abstract: This disclosure provides drilling fluids and additives as well as fracturing fluids and additives that contain cellulose nanofibers and/or cellulose nanocrystals. In some embodiments, hydrophobic nanocellulose is provided which can be incorporated into oil-based fluids and additives. These water-based or oil-based fluids and additives may further include lignosulfonates and other biomass-derived components. Also, these water-based or oil-based fluids and additives may further include enzymes. The drilling and fracturing fluids and additives described herein may be produced using the AVAP® process technology to produce a nanocellulose precursor, followed by low-energy refining to produce nanocellulose for incorporation into a variety of drilling and fracturing fluids and additives.

Abstract: The disclosure provides a process for separating fermentation inhibitors from a biomass-derived hydrolysate, comprising: introducing a biomass-derived liquid hydrolysate stream to a stripping column; introducing a steam-rich vapor stream to the stripping column to strip fermentation inhibitors (such as acetic acid) from the liquid hydrolysate stream; recovering a stripped liquid stream and a stripper vapor output stream; compressing the stripper vapor output stream; introducing the compressed vapor stream, and a water-rich liquid stream, to an evaporator; recovering, from the evaporator, an evaporated liquid stream and an evaporator output vapor stream; and recycling the evaporator output vapor stream to the stripping column as the steam-rich vapor stream. Other variations utilize a rectification column to recover a rectified liquid stream and a rectification column vapor stream, and recycle the rectification column vapor stream to the stripping column as the steam-rich vapor stream.

Abstract: Various processes are disclosed for producing nanocellulose materials following steam extraction or hot-water digestion of biomass. Processes are also disclosed for producing nanocellulose materials from a wide variety of starting pulps or pretreated biomass feedstocks. The nanocellulose materials may be used as rheology modifiers in many applications. Water-based and oil-based drilling fluid formulations and additives are provided. Also, water-based and oil-based hydraulic fracturing fluid formulations and additives are provided. In other embodiments, polymer-nanocellulose composites are provided.