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 total mechanical energy may be less than 500 kilowatt-hours per ton. 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.

Abstract: This invention provides processes to convert biomass into energy-dense biomass for combustion, alone or in combination with another solid fuel. Some embodiments provide processes for producing energy-dense biomass from cellulosic biomass, comprising extracting the feedstock with steam and/or hot water to produce an extract liquor containing hemicellulosic oligomers, dissolved lignin, and cellulose-rich solids; separating the extract liquor, to produce dewatered cellulose-rich solids; hydrolyzing the dewatered cellulose-rich solids, thereby removing a portion of the cellulose, to produce intermediate solids (with higher energy density) and a hydrolysate; drying the intermediate solids to produce energy-dense biomass; and optionally recovering fermentable sugars from the hydrolysate. The energy-dense biomass may be pelletized into biomass pellets, which may have a similar energy density as torrefied pellets from wood.

Abstract: A method is disclosed for the production of alcohol and other bioproducts hemicelluloses extracted from biomass prior to thermal conversion of the biomass to energy. The process can be integrated with the host plant process to minimize the energy loss from extracting hemicelluloses. Also disclosed is a stepwise enzymatic break down of cellulose fibers from a pulping operation which is performed with the redeployment of equipment and vessels contained within typical existing pulp and paper manufacturing mills. The preferred feedstock is highly delignified pulp from acid or alkaline pulping process or from bleaching stage.

Abstract: This invention provides processes and apparatus to convert biomass, including wood and agricultural residues, into low-ash biomass pellets for combustion, alone or in combination with another solid fuel. Some embodiments provide processes for producing low-ash biomass from cellulosic biomass, comprising providing an aqueous extraction solution with acetic acid; extracting the feedstock to produce an extract liquor containing soluble ash, hemicellulosic oligomers, acetic acid, dissolved lignin, and cellulose-rich solids; dewatering and drying the cellulose-rich, lignin-rich solids to produce a low-ash biomass; hydrolyzing the hemicellulosic oligomers to produce hemicellulosic sugars, wherein additional acetic acid is generated; removing a vapor stream comprising vaporized acetic acid from the extract; and recycling the vapor or its condensate to provide some starting acetic acid for the extraction solution. The disclosed processes can produce clean power from biomass.

Abstract: The present invention relates to producing chemicals and biofuels from wood material, e.g. mixed forest biomass. Specifically, the invention concerns a process for conditioning spent liquor produced by SO2-ethanol-water (SEW) fractionation of wood chips for fermentation to butanol, ethanol and acetone/isopropanol (so called ABE process) by Clostridia bacteria.

Abstract: In some variations, the invention provides a process for fractionating biomass, comprising: in a digestor, fractionating a biomass feedstock in the presence of a solvent for lignin, sulfur 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 the cellulose-rich solids to produce glucose; neutralizing, with lime, a hydrolysate liquid containing the hemicellulosic monomers and the glucose, thereby generating gypsum; heating the gypsum to form calcium sulfate; reducing the calcium sulfate with a reductant (such as syngas) to generate calcium oxide and sulfur dioxide; and recycling the calcium oxide and the sulfur dioxide.

Abstract: This invention provides processes to convert biomass into energy-dense biomass for combustion, alone or in combination with another solid fuel. Some embodiments provide processes for producing fermentable sugars and energy-dense biomass from cellulosic biomass, comprising extracting the feedstock with steam and/or hot water to produce an extract liquor containing hemicellulosic oligomers, dissolved lignin, and cellulose-rich solids; separating the extract liquor, to produce dewatered cellulose-rich solids; hydrolyzing the dewatered cellulose-rich solids, thereby removing a portion of the cellulose, to produce intermediate solids (with higher energy density) and a hydrolysate; drying the intermediate solids to produce energy-dense biomass; and recovering fermentable sugars from the hydrolysate. The energy-dense biomass may be pelletized into biomass pellets, which may have a similar energy density as torrefied pellets from wood.

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: A method for the production water insoluble reactive lignin having low sulfur content and lignosulfonates from lignocellulosic material in a batch or continuous process. Lignocellulosic material is fractionated to produce water insoluble native lignin and lignosulfonates in various ratios, while preserving the cellulose and hydrolyzed hemicelluloses using water, ethanol and sulfur dioxide.

Abstract: This invention provides processes to convert biomass, including wood and agricultural residues, to levulinic acid and co-products. Some variations treat feedstock with steam and/or hot water to produce an extract liquor containing hemicellulosic oligomers, lignin, and cellulose-rich solids, wherein the hemicellulosic oligomers comprise C5 hemicelluloses and C6 hemicelluloses; separate the cellulose-rich solids from the extract liquor, to produce dewatered solids containing cellulose and lignin; dehydrate the hemicellulosic oligomers to convert the C6 hemicelluloses directly to 5-hydroxymethylfurfural; and convert the 5-hydroxymethylfurfural to levulinic acid. Also, the cellulose may be dehydrated directly to 5-hydroxymethylfurfural, which may then be converted to additional levulinic acid. Various biorefinery embodiments are disclosed, in which C5 and C6 sugars are processed separately or in combination.

Abstract: In some variations, the invention provides a deicer composition comprising alkali acetate, a solvent (such as water) for the alkali acetate, and a corrosion inhibitor comprising lignin or a lignin derivative. The acetate and the lignin or lignin derivative are preferably each derived from the same biomass feedstock. In some embodiments, the alkali is selected from the group consisting of potassium, sodium, magnesium, calcium, and combinations thereof. In some embodiments, the alkali acetate is present in a concentration from about 30 wt % to about 99 wt %. Deicer products may be a crystallized or dried form of the deicer composition.

Abstract: A method is presented for the production of cellulosic ethanol, acetic acid and derivatives from the extract containing fibers and hemicelluloses after steam cooking of biomass in a host plant. The process is integrated with the host plant process to minimize the effect of loss of heat value from the extracted hemicelluloses and eliminate the need for the waste water treatment plant.

Abstract: In some variations, the invention provides a process for fractionating biomass, comprising: fractionating the biomass in the presence of a solvent for lignin, sulfur dioxide, and water, to produce a liquor containing hemicellulose, cellulose-rich solids, and lignin; hydrolyzing the hemicellulose contained in the liquor, to produce hemicellulosic monomers; hydrolyzing the cellulose-rich solids to produce glucose; and recovering the hemicellulosic monomers and the glucose, as fermentable sugars, wherein a metal sulfite or metal bisulfite additive is introduced to react directly or indirectly with lignin to produce sulfonated lignin. The disclosed processes may enhance lignin separations as well as promote the co-product potential of lignin.

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: In some variations, the invention provides a process for producing furfural, 5-hydroxymethylfurfural, and/or levulinic acid from cellulosic biomass, comprising: fractionating the feedstock in the presence of a solvent for lignin, sulfur dioxide, and water, to produce a liquor containing hemicellulose, cellulose-rich solids, and lignin; hydrolyzing the hemicellulose contained in the liquor, to produce hemicellulosic monomers; dehydrating the hemicellulose to convert at least a portion of C5 hemicelluloses to furfural and to convert at least a portion of C6 hemicelluloses to 5-hydroxymethylfurfural; converting at least some of the 5-hydroxymethylfurfural to levulinic acid and formic acid; and recovering at least one of the furfural, the 5-hydroxymethylfurfural, or the levulinic acid. Other embodiments provide a process for dehydrating hemicellulose to convert oligomeric C5 hemicelluloses to furfural and to convert oligomeric C6 hemicelluloses to 5-hydroxymethylfurfural.

Abstract: The invention provides processes for producing fermentable sugars from whole biomass that includes cellulose, hemicellulose, lignin, and non-lignocellulosic sugars. Some variations fractionate the whole feedstock in the presence of sulfur dioxide, a solvent for lignin, and water, to produce a liquor containing hemicellulose, cellulose-rich solids, lignin, and the non-lignocellulosic sugars. After removing the cellulose-rich solids from the liquor, the hemicellulose is hydrolyzed to hemicellulosic monomers; the cellulose-rich solids are hydrolyzed to glucose; and the hemicellulosic monomers, the glucose, and the non-lignocellulosic sugars are all recovered (separately or in combination) as fermentable sugars. The whole biomass feedstock may be selected from sugarcane, energy cane, corn, wheat, rice, sugar beets, energy beets, etc. Typical non-lignocellulosic sugars are sucrose or starch, which may be converted to monomer sugars during initial fractionation.

Abstract: The present invention provides a process for fractionating lignocellulosic biomass, comprising: contacting biomass with SO2, water, and optionally a first solvent, to produce intermediate solids; then contacting the intermediate solids with SO2, water, and a second solvent, to produce cellulose-rich solids and a liquid phase comprising hemicelluloses and lignin. The first concentration of SO2 may be lower or higher than the second concentration of SO2. It is desirable to vary the SO2 and solvent concentrations in different stages to optimize the removal of hemicellulose versus lignin. The resulting cellulose-rich material can contain very low hemicellulose, very low lignin, or both low hemicellulose and low lignin. High-purity cellulose is useful both for producing glucose as well as for cellulose products or derivatives. The hemicelluloses may be hydrolyzed to produce monomeric sugars, and the lignin may be recovered as a co-product.

Abstract: In some variations, the invention provides a process for producing purified cellulose, comprising: providing a feedstock comprising lignocellulosic biomass; contacting the feedstock with sulfur dioxide, water, and a solvent for lignin, to produce intermediate solids and a liquid phase comprising hemicelluloses and lignin; mildly bleaching the intermediate solids to further delignify the intermediate solids, thereby generating cellulose-rich solids; and washing the cellulose-rich solids to generate purified cellulose with less than 2 weight percent lignin. The bleaching may employ bleaching agents including lignin-modifying enzymes. The bleaching and washing steps may be combined. It is also possible to carry out bleaching prior to, or simultaneously with, biomass fractionation in the digestor, which may help reduce downstream lignin precipitation. The purified cellulose may be utilized for making cellulose materials or cellulose derivatives, or for hydrolysis to produce glucose.

Abstract: Aspects of the AVAP® and Green Power+® technologies may be integrated, as disclosed herein. The present invention, in some variations, couples a first step of steam or hot-water extraction of biomass, with fractionation of the resulting solids using sulfur dioxide (or other acid), an alcohol (or other solvent), and water. In other variations, a first step of fractionation with sulfur dioxide (or other acid), an alcohol (or other solvent), and water is followed by treatment with steam or hot water to reduce hemicellulose content of the final solids. Some embodiments provide cellulose materials with low lignin and low hemicellulose content. Such cellulose materials are useful for making glucose by hydrolysis, as a pulp product, or as purified cellulose for making cellulose derivatives.

Abstract: The present invention generally provides methods of improving lignin separation during biomass fractionation with an acid to release sugars and a solvent for lignin (such as ethanol). In some embodiments, a digestor is employed to fractionating a feedstock in the presence of a solvent for lignin, sulfur dioxide, and water, to produce a liquor containing hemicellulose, cellulose-rich solids, and lignin. A solid additive is added to the digestor, wherein the solid additive combines with at least a portion of the lignin. Then a mixture of lignin and the solid additive is separated from the liquor, prior to hemicellulose recovery. Optionally, a solid additive may also be introduced to a hydrolysis reactor for converting hemicellulose oligomers to monomers, to improve separation of acid-catalyzed lignin. In some embodiments, the solid additive is gypsum or a gypsum/lignin mixture.