BR112019027082B1 - NANOLIGNOCELLULOSE COMPOSITIONS AND PROCESSES FOR PRODUCING THESE COMPOSITIONS - Google Patents

Abstract

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

Description

PRIORITY DATA

[001] This international patent application claims priority to US Provisional Patent Application 62/523,293, filed on June 22, 2017, and US Patent Application 16/014,589, filed on June 21, 2018, each of which is incorporated by reference in the present invention.

FIELD

[002] The present invention relates, in general, to nanocellulose and related materials produced by fractionation of lignocellulosic biomass and further processing of the cellulose fraction.

BACKGROUND

[003] Biomass refining (or biorefining) has become more prevalent in industry. Cellulose fibers and sugars, hemicellulose sugars, lignin, singás, and derivatives of these intermediates are being used for the production of chemicals and fuels. In fact, we are now seeing the commercialization of integrated biorefineries that are capable of processing incoming biomass in the same way that petroleum refineries now process crude oil. Underutilized lignocellulosic biomass feedstocks have the potential to be much cheaper than oil on a carbon basis and also much better from an environmental life cycle perspective.

[004] Lignocellulosic biomass is the most abundant renewable material on the planet and has long been recognized as a potential feedstock for the production of chemicals, fuels and materials. Lignocellulosic biomass typically comprises mainly cellulose, hemicellulose and lignin. Cellulose and hemicellulose are natural sugar polymers, and lignin is an aromatic/aliphatic hydrocarbon polymer that reinforces the entire biomass network. Some forms of biomass (e.g. recycled materials) do not contain hemicellulose.

[005] Despite being the most available natural polymer on Earth, it is only recently that cellulose has gained prominence as a nanostructured material, in the form of nanocrystalline cellulose (NCC), nanofibrillar cellulose (NFC), and bacterial cellulose (BC). Nanocellulose is being developed for use in a wide variety of applications, such as polymer reinforcement, antimicrobial films, biodegradable food packaging, printing papers, pigments and inks, paper and board packaging, barrier films, adhesives, biocomposites , wound healing, pharmaceutical and drug dispensing, textiles, water-soluble polymers, construction materials, recyclable interior and structural components for the transport industry, rheology modifiers, low-calorie food additives, thickeners for cosmetics, binders for pharmaceutical tablets, bioactive paper, Pickering stabilizers for emulsion and particle-stabilized foams, ink formulations, optical switching films, and detergents.

[006] Cellulose pulp derived from biomass can be converted into nanocellulose by mechanical processing. Although the process may be simple, disadvantages include high energy consumption, damage to fibers and particles due to intense mechanical treatment, and a wide distribution in diameter and length of fibrils.

[007] Improved processes for producing nanocellulose from biomass at reduced energy costs are needed in the art. Furthermore, improved starting materials (i.e., cellulose pulps derived from biomass) are required in the art for the production of nanocellulose. For some applications, it is desirable to produce nanocellulose with high hydrophobicity.

[008] There is also a need in the art to increase the strength of weak cellulose fibers, and improve certain properties of paper, media pulp and cellulose pulp products.

SUMMARY

[009] Some variations provide a nanolignocellulose composition comprising, on a dry weight, ash-free and acetyl-free basis, from about 35% by weight to about 80% by weight cellulose nanofibrils, cellulose microfibrils or a combination thereof, from about 15% by weight to about 45% by weight lignin, and from about 5% by weight to about 20% by weight hemicelluloses. Hemicelluloses may contain xylan or mannan as the main component.

[010] In certain embodiments, the composition comprises from about 40% by weight to about 70% by weight cellulose nanofibrils, cellulose microfibrils, or a combination thereof on an ash-free, dry weight basis. and acetyl free.

[011] In certain embodiments, the composition comprises from about 45% by weight to about 60% by weight cellulose nanofibrils, cellulose microfibrils, or a combination thereof on an ash-free, dry weight basis. and acetyl free.

[012] In certain embodiments, the composition comprises from about 20% by weight to about 40% by weight lignin on a dry weight, ash-free and acetyl-free basis.

[013] In certain embodiments, the composition comprises from about 25% by weight to about 35% by weight lignin on a dry weight, ash-free and acetyl-free basis.

[014] In certain embodiments, the composition comprises from about 7% by weight to about 15% by weight hemicelluloses on a dry weight, ash-free and acetyl-free basis.

[015] In certain embodiments, the composition comprises from about 8% by weight to about 14% by weight hemicelluloses on a dry weight, ash-free and acetyl-free basis.

[016] In some embodiments, said nanolignocellulose composition is characterized by at least 99% completion of filtration (such as 100% completion) in less than 100 minutes.

[017] The present invention also provides a cellulose pulp product or a paper product containing the disclosed nanolignocellulose composition.

[018] Some variations provide a process for producing a nanolignocellulose composition, the process comprising: (a) providing a lignocellulosic biomass feedstock; (b) digesting the feedstock with a reaction solution including steam and/or hot water in a digester under effective reaction conditions to produce a digestate stream containing solids rich in cellulose, hemicellulose oligomers, and lignin; (c) optionally washing the cellulose-rich solids to remove at least a portion of the hemicellulose oligomers and/or at least a portion of the lignin from the cellulose-rich solids; (d) mechanically treating the cellulose-rich solids to form a nanolignocellulose composition containing cellulose nanofibrils and/or cellulose nanocrystals, hemicelluloses and lignin; and (e) recovering the nanolignocellulose composition.

[019] In some processes, the nanolignocellulose composition comprises, on a dry weight, ash-free and acetyl-free basis, from about 35% by weight to about 80% by weight cellulose nanofibrils, cellulose microfibrils , or a combination thereof, from about 15% by weight to about 45% by weight lignin, and from about 5% by weight to about 20% by weight hemicelluloses.

[020] In some processes, the nanolignocellulose composition is characterized by at least 99% completion of filtration in less than 100 minutes.

[021] The process may additionally include a cellulose pulp product or a paper product containing the nanolignocellulose composition. For example, the nanolignocellulose composition can be fed to a paper machine to produce a paper product.

BRIEF DESCRIPTION OF FIGURES

[022] FIG. 1A is an SEM image of an example nanocellulose produced experimentally by refining and homogenizing material produced from the extraction of biomass in hot water.

[023] FIG. 1B is an SEM image of an example nanocellulose produced experimentally by refining and homogenizing material produced from the extraction of biomass in hot water.

[024] FIG. 1C is an SEM image of an example nanocellulose produced experimentally, by refining and homogenizing material produced from the extraction of biomass in hot water.

[025] FIG. 2 is an optical micrograph at 40x magnification of washed nanolignocellulose produced in Example 1.

[026] FIG. 3 is an optical micrograph at 40x magnification of washed nanolignocellulose produced in Example 2.

[027] FIG. 4 is a graph of the filtration rate of the nanolignocellulose of Example 2 compared to the prior art Kraft cellulose pulp.

DETAILED DESCRIPTION OF SOME FORMS OF IMPLEMENTATION

[028] This description will allow one skilled in the art to make and use the invention, and describes various embodiments, adaptations, variations, alternatives and uses of the invention. These and other embodiments, features and advantages of the present invention will become more apparent to those skilled in the art when taken with reference to the following detailed description of the invention in conjunction with any accompanying drawings.

[029] As used in this specification and the attached claims, the singular forms “a”, “an” and “a” and “the” include plural referents, unless the context clearly indicates otherwise. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as is commonly understood by one of ordinary skill in the art to which this invention belongs. All percentage-based numbers and composition ranges are percentages by weight unless otherwise noted. All ranges of numbers or conditions must encompass any specific value contained in the range, rounded to any appropriate decimal point.

[030] Unless otherwise indicated, all numbers expressing parameters, reaction conditions, component concentrations, and so on used in the specification and claims should be understood as being modified in all cases by the term “ about". Suitably, unless otherwise indicated, the numerical parameters set forth in the following specification and in the attached claims are approximations that may vary depending on at least one specific analytical technique.

[031] The term “comprising”, which is synonymous with “including”, “containing” or “characterized by” is inclusive or open and does not exclude additional unspecified elements or steps of the method. “Comprising” is a technical term used in claim language that means the named claim elements are essential, but other claim elements can be added and still form a construct within the scope of the claim.

[032] As used in the present invention, the expression “consisting of” excludes any element, step or ingredient not specified in the claim. When the expression “consists of” (or variations thereof) appears in a body clause of a claim, rather than immediately following the preamble, it limits only the element set forth in that clause; other elements are not excluded from the claim as a whole. As used herein, the expression “consisting essentially of” limits the scope of a claim to the specified elements or method steps other than those that do not materially affect the basis and novel feature(s) of the claimed object.

[033] With respect to the terms “comprising”, “consisting of” and “consisting essentially of”, where one of these three terms is used in the present invention, the subject matter currently disclosed and claimed may include the use of any of the other two terms . Thus, in some embodiments not explicitly cited, any case of “comprising” may be replaced by “consisting of” or, alternatively, “consisting essentially of”.

[034] Some variations are based on the discovery of a surprisingly simple process for converting lignocellulosic biomass into nanocellulose or nanolignocellulose. Biomass can be steamed or immersed in hot water to dissolve hemicelluloses. This step is followed by mechanical refining of the cellulose-rich (and lignin-rich) solids.

[035] Some variations provide a nanolignocellulose composition comprising, on a dry weight, ash-free and acetyl-free basis, from about 35% by weight to about 80% by weight cellulose nanofibrils, cellulose microfibrils or a combination thereof, from about 15% by weight to about 45% by weight lignin, and from about 5% by weight to about 20% by weight hemicelluloses.

[036] In various embodiments, the nanolignocellulose composition may include about (or at least about, or at most about) 30, 35, 40, 45, 50, 55, 60, 65, 75, 75, 80, 85 or 90% by weight cellulose nanofibrils, cellulose microfibrils, or a combination thereof, based on dry weight, ash-free and acetyl-free.

[037] In various embodiments, the nanolignocellulose composition may include about (or at least about, or at most about) 10, 15, 20, 25, 30, 35, 40, 45 or 50% by weight of lignin, on a dry weight basis, ash-free and acetyl-free.

[038] In various embodiments, the nanolignocellulose composition may include about (or at least approximately or at most approximately) 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 , 14, 15, 16, 17, 18, 19 or 20% by weight of hemicelluloses, a dry weight basis, ash-free and acetyl-free. Hemicelluloses may contain xylan or mannan as the main component.

[039] A “dry weight basis, ash-free and acetyl-free” means that the concentrations cited are (i) absolutely free of any water, not including H-OH groups chemically contained, for example, in sugar polymers; (ii) free of any ash, including loose ash (e.g., sand or dirt) and bound ash (e.g., metal oxides that do not readily extract from solids); and (iii) acetyl groups attached to hemicellulose components, or free acetic acid derived from the acetyl groups.

[040] In certain embodiments, the composition comprises from about 40% by weight to about 70% by weight cellulose nanofibrils, cellulose microfibrils, or a combination thereof on an ash-free, dry weight basis. and acetyl free.

[041] In certain embodiments, the composition comprises from about 45% by weight to about 60% by weight cellulose nanofibrils, cellulose microfibrils or a combination thereof on a dry weight, ash-free and acetyl free.

[042] In certain embodiments, the composition comprises from about 20% by weight to about 40% by weight lignin on a dry weight, ash-free and acetyl-free basis.

[043] In certain embodiments, the composition comprises from about 25% by weight to about 35% by weight lignin on a dry weight, ash-free and acetyl-free basis.

[044] In certain embodiments, the composition comprises from about 7% by weight to about 15% by weight of hemicelluloses on a dry weight, ash-free and acetyl-free basis.

[045] In certain embodiments, the composition comprises from about 8% by weight to about 14% by weight hemicelluloses on a dry weight, ash-free and acetyl-free basis.

[046] The nanolignocellulose composition may contain water as moisture or in a slurry of solids, for example. The nanolignocellulose composition, on an ash-free and acetyl-free (but wet basis) basis, may contain at least about (or at least about, or at most about) 5, 10, 15, 20, 25 , 30, 35, 40, 45, 50, 60, 70, 80, 90% by weight of water or more.

[047] The nanolignocellulose composition may contain ash. The nanolignocellulose composition, on a dry weight basis and without acetyl, may contain at least about (or at least about or at most about) 0.1; 0.5; 1; two; 3; 4; 5% by weight of ash or more.

[048] The nanolignocellulose composition may contain acetyl groups. The nanolignocellulose composition, on an ash-free, dry weight basis, may contain at least about (or at least about, or at most about) 0.1; 0.5; 1.0; 1.5; 2.0; 2.5; 3.0% by weight acetyl content or more.

[049] In some embodiments, said nanolignocellulose composition is characterized by at least 99% completion of filtration (such as 100% completion) in less than 100 minutes.

[050] The present invention also provides a cellulose pulp product or a paper product containing a disclosed nanolignocellulose composition.

[051] In some variations, a paper mill co-produces nanolignocellulose and adds this material back to its own feedstock as a way to prepare a stronger sheet, or a smoother sheet, or to provide a cheaper feedstock. for the final paper product. In some embodiments, nanolignocellulose is produced using an existing low-consistency refiner, as a side operation in the factory or in a nearby factory. At least part of the resulting nanolignocellulose is added back to the mixture.

[052] This concept may result in the ability to use lower-cost wood as the main raw material to produce cellulose pulp. Many paper mills use a mixture of hardwoods and softwoods to achieve a desired combination of strength and sheet formation/smoothness. In addition to replacing higher-cost raw materials, nanolignocellulose can act as a retention aid for paper machines. Thus, a paper machine can use the function of a retention aid, and also the strength of the sheet of the same material (nanolignocellulose).

[053] The principles of the invention can be applied to any type of cellulose or mill, including chemical (e.g., AVAP®, kraft or sulfite), mechanical, thermomechanical, chemothermal, hydrothermal-mechanical (e.g., GreenBox+® or GP3+) ™) or other types of pulp. Chemical pulping generally degrades lignin and hemicellulose into small water-soluble molecules that can be washed from cellulose fibers without depolymerizing the cellulose fibers. AVAP® pulping removes lignin and hemicelluloses without significant sugar degradation, allowing the recovery of all main components (cellulose, hemicellulose and lignin). The various mechanical pulping methods, such as mechanical mill pulping and refining, physically tear the cellulose fibers from each other. Much of the lignin continues to adhere to the fibers. Strength is compromised because the fibers can be cut. Related hybrid pulping methods use a combination of chemical and heat treatment to initiate an abbreviated chemical pulping process, followed by a mechanical treatment to separate the fibers. These hybrid methods include thermomechanical and polymetromechanical pulping. Chemical and thermal treatments reduce the amount of energy subsequently required by mechanical treatment, and also reduce the amount of strength loss experienced by the fibers.

[054] In some preferred embodiments, the invention is applied to a thermomechanical cellulose pulp mill or a hydrothermal-mechanical cellulose pulp mill.

[055] In some embodiments, some of the thermomechanical or hydrothermal-mechanical cellulose pulps that are produced from the normal pulping operation are sent to a side nanocellulose production operation, involving mechanical refining of the thermomechanical or hydrothermal-mechanical cellulose pulp. hydrothermal-mechanical to generate nanocellulose particles (e.g. cellulose nanofibrils). Commonly owned US Patent Application No. 15/278,800 filed on September 28, 2016, entitled “PROCESSES FOR PRODUCING NANOCELLULOSE, AND NANOCELLULOSE COMPOSITIONS PRODUCED THEREFROM”, is incorporated by reference in the present invention for its teachings of thermomechanical pulp conversion or hydrothermal-mechanical in nanocellulose, in some embodiments.

[056] In some variations, nanocellulose can be added to corrugated medium cellulose pulp having inadequate strength properties, so that the resulting composite meets, or exceeds, the strength properties required for the intended application. Although the principles of these embodiments are not limited to any specific source of corrugated media or nanocellulose, preferred embodiments combine corrugated media produced by steam or hot water extraction (known as GreenBox+® technology) with nanocellulose produced by refining. of cellulose pulp obtained by fractionating biomass in acid solvent (known as AVAP® technology).

[057] In some preferred embodiments, steam or hot water extraction of the initial biomass is employed to produce cellulose pulp, which is then refined and optionally washed to produce corrugated medium cellulose pulp. Refers to commonly held US Patent Application No. 14/044,784 filed on October 2, 2013 (published as US 20140096922A1 on April 10, 2014), which is incorporated herein by reference in the present invention, for process conditions example for producing corrugated medium cellulose pulp, in various embodiments.

[058] In some embodiments, hot water extraction of the initial biomass is employed to produce cellulose pulp, which is then refined to produce nanolignocellulose. As intended in the present invention, "nanolignocellulose" is a material that contains cellulose particles closely associated (i.e., chemically and/or physically) with substantial amounts of lignin and hemicellulose. The cellulose (within the nanolignocellulose particles) may include nanofibrils and/or microfibrils. The percentage of lignin (within the nanolignocellulose particles) is generally at least about 20% by weight, and the percentage of hemicellulose (within the nanolignocellulose particles) is generally at least about 5% by weight. Certain embodiments employ hot water digestion and/or refining, as described in US Patent Application No. 15/047,608, published as US 20160244788 on August 25, 2016, which is incorporated herein by reference into the present invention. .

[059] Effective hot water extraction conditions may include contact of lignocellulosic biomass with steam (at various pressures in saturated, superheated or supersaturated form) and/or hot water. In some embodiments, the HWE step is performed using liquid hot water at a temperature of about 140-220°C, such as about 150°C, 160°C, 170°C, 175°C, 175°C , 180°C, 185°C, 190°C, 200°C or 210°C. In some embodiments, the HWE step is performed using liquid hot water with a residence time of about 1 minute to about 60 minutes, such as about 2, 2.5; 3; 3.5; 4; 5; 7.5; 10; 12.5; 15; 20; 25; 30; 35; 40; 45; 50 or 55 minutes.

[060] In certain embodiments, lignin-coated nanocellulose (preferably lignin-coated cellulose nanofibrils) is added to the corrugated medium cellulose pulp. Without being limited by theory, lignin in nanofibrils can strengthen the moisture resistance of corrugated media paper. The production of lignin-coated nanocellulose is described in detail below. In some embodiments, lignin fills the voids between the fibers during pressing.

[061] Using well-known techniques, the corrugated medium product can be produced from the cellulose pulp of the modified corrugated medium (with nanocellulose). See, for example, Twede and Selke, “Cartons, crates and corrugated board: handbook of paper and wood packaging technology,” DEStech Publications, pages 41-56, 2005; and Foster, “Boxes, Corrugated,” in The Wiley Encyclopedia of Packaging Technology, 1997, eds. Brody A and Marsh K, 2nd ed.

[062] As intended in the present invention, "nanocellulose" is broadly defined to include a range of cellulosic materials, including, but not limited to, microfibrillated cellulose (or cellulose microfibrils), nanofibrillated cellulose (or cellulose nanofibrils), microcrystalline cellulose , nanocrystalline cellulose, and particulate or fibrillated dissolving cellulose pulp. Typically, nanocellulose, as provided in the present invention, will include particles having at least one length dimension (e.g., diameter) on the nanometer scale.

[063] “Nanofibrillated cellulose” or equivalently “cellulose nanofibrils” means fibers or regions of cellulose that contain nanometer-sized particles or fibers, or micron-sized and nanometer-sized particles or fibers. “Nanocrystalline cellulose” or equivalently “cellulose nanocrystals” means particles, regions or crystals of cellulose that contain domains sized in nanometers, or domains sized in microns and nanometers. “Micron size” includes 1 μm to 100 μm and “nanometer” size includes 0.01 nm to 1000 nm (1 μm). Larger domains (including long fibers) may also be present in these materials.

[064] Certain exemplary embodiments of the invention will now be described. These embodiments are not intended to limit the scope of the invention as claimed. The order of steps may vary, some steps may be omitted and/or other steps may be added. Reference made in the present invention to the first stage, the second stage, etc. It is only for the purpose of illustrating some embodiments.

[065] Some variations provide a cellulose pulp product comprising cellulose and nanolignocellulose, wherein the nanocellulose includes cellulose nanofibrils and/or cellulose nanocrystals, and wherein the nanolignocellulose is derived from cellulose in a separate step of the pulping process to produce cellulose.

[066] In some embodiments, the pulping process is thermomechanical pulping or hydrothermal-mechanical pulping. The cellulose pulp product may be paper or a structural object (e.g. box, panel, wood derivatives, etc.) other than paper.

[067] In preferred embodiments, the cellulose pulp product is stronger than an identical cellulose pulp product without nanolignocellulose. In some embodiments, the cellulose pulp product is softer than an identical cellulose pulp product without the nanolignocellulose.

[068] The pulping process is thermomechanical pulping, in certain embodiments, and the nanolignocellulose essentially consists of nanofibrils containing cellulose, lignin and hemicellulose. Nanofibrils can be produced by mechanically refining the cellulose precursor (with significant amounts of lignin and hemicelluloses) from thermomechanical pulping.

[069] Other variations provide a corrugated medium cellulose pulp composition comprising cellulose pulp and nanolignocellulose, wherein the nanolignocellulose includes hydrophobic nanofibrils. In some embodiments, the nanolignocellulose is present in a concentration of at least about 0.1 wt%, 0.5 wt%, 1 wt%, 2 wt%, 5 wt%, or 10 wt%. weight of the composition on a dry basis. In certain embodiments, the nanolignocellulose is a significant portion of the cellulose feedstock, i.e., about 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt% or more. .

[070] In some embodiments of the corrugated medium cellulose composition, the cellulose pulp is a mechanical cellulose pulp or thermomechanical cellulose pulp (for example, GreenBox+® cellulose). In some embodiments, the cellulose pulp is a chemical cellulose pulp (e.g., AVAP®, kraft, sulfite or soda cellulose pulp).

[071] In some embodiments, the process further comprises producing a corrugated medium product from the corrugated medium cellulose pulp composition. The first amount of lignocellulosic biomass and the second amount of lignocellulosic biomass may be from the same biomass source or different biomass sources.

[072] In some embodiments, nanolignocellulose is hydrophobic cellulose containing lignin. In these or other embodiments, the nanolignocellulose is predominantly in the form of nanofibrils, microfibrils or a mixture thereof.

[073] In some embodiments, a system is provided to perform the process, as disclosed. The system may include a first subsystem for producing the first cellulose pulp at a first location and a second subsystem for producing the nanolignocellulose at a second location other than the first location. Production of the final product can be done in one of the first or second subsystems or in another location.

[074] In some embodiments, nanolignocellulose is derived from a biomass source selected from the group consisting of hardwoods, softwoods, agricultural residues and combinations thereof.

[075] In some embodiments, nanolignocellulose is obtained from the fractionation of 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 refine the cellulose-rich solids to generate nanolignocellulose. In certain embodiments, the acid is sulfur dioxide and the solvent is ethanol. In certain embodiments, an AVAP® process is used to produce nanolignocellulose to reinforce cellulose fibers.

[076] “Strengthening” can be carried out by simple mixing, crushing, grinding, stirring, deposition/drying or other treatments, in various embodiments.

[077] In some embodiments, the method further comprises producing a single fiber product from cellulose fibers. In these or other embodiments, the method additionally comprises producing a composite from cellulose fibers. Reinforcing weak fibers with nanolignocellulose can increase strength in composite and single fiber products and other products.

[078] In some embodiments, a product is first made from cellulose fibers and then the product (not cellulose pulp) is reinforced with nanolignocellulose. In these embodiments, if desired, reinforcement can be made to the bulk product or to selected surfaces or regions, for example.

[079] The biomass feedstock can be selected from hardwoods, softwoods, forestry residues, eucalyptus, industrial wastes, cellulose and paper pulp wastes, consumer wastes or combinations thereof. Some embodiments use agricultural residues, which include lignocellulosic biomass associated with food crops, annual grasses, energy crops or other annually renewable raw materials. Example agricultural residues include, but not limited to, corn stover, corn fiber, wheat straw, sugar cane bagasse, sugar cane straw, rice straw, oat straw, barley straw, miscanthus, straw /energy sugarcane residue, or combinations thereof. The process disclosed in the present invention benefits from the flexibility of the raw material; It is effective for a wide variety of cellulose-containing raw materials.

[080] As used in the present invention, “lignocellulosic biomass” means any material that contains cellulose, lignin and hemicellulose. Mixtures of one or more types of biomass can be used. In some embodiments, the biomass feedstock comprises a lignocellulosic component (such as that described above), in addition to a sucrose-containing component (e.g., sugar cane or energy cane) and/or a starch component ( e.g. corn, wheat, rice, etc.). Various moisture levels can be associated with the initial biomass. The biomass feedstock need not be, but can be, relatively dry. In general, biomass is in the form of particles or chips, but particle size is not critical in this invention.

[081] In some embodiments, the cellulose-rich solids are treated with a total mechanical energy of less than about 5,000 kilowatt-hours per ton (1 ton = 907.18 kg) of the cellulose-rich solids, such as less than around 4000, 3000, 2000 or 1000 kilowatt-hours per ton (1 ton = 907.18 kg) of cellulose-rich solids. Power consumption may be measured in any other suitable unit. An ammeter that measures the current drawn by a motor that drives the mechanical treatment device is one way to obtain an estimate of total mechanical energy.

[082] Mechanical treatment may employ one or more known technique(s), such as, but in no way limited to, grinding, crushing, beating, sonication or any other means to form or release nanofibrils and/or nanocrystals in cellulose. Essentially, any type of factory or device that physically separates fibers into fibrils can be used. These plants are well known in the industry and include, without limitation, Valley beaters, single disc refiners, double disc refiners, conical refiners including wide angle and narrow angle, cylindrical refiners, homogenizers, microfluidizers and other types of grinding apparatus or crushing. See, for example, Smook, Handbook for Pulp & Paper Technologists, Tappi Press, 1992; and Hubbe et al., “Cellulose Nanocomposites: A Review,” BioResources 3(3), 929-980 (2008).

[083] The extent of mechanical treatment can be monitored during the process by any of several means. Certain optical instruments can provide continuous data relating to fiber length distributions and % fines, one of which can be used to define end points for the mechanical treatment step. Time, temperature and pressure may vary during mechanical treatment. For example, in some embodiments, sonication for a time of about 5 minutes to 2 hours, at room temperature and pressure, can be used.

[084] In some embodiments, a portion of the cellulose-rich solids is converted into nanofibrils, while the remainder of the cellulose-rich solids is not fibrillated. In various embodiments, about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 99% or substantially all of the cellulose-rich solids are fibrillated. in nanofibrils. In some embodiments, a portion of the nanofibrils are converted into nanocrystals, while the remainder of the nanofibrils are not converted into nanocrystals. During drying, it is possible that some nanocrystals come together again and form nanofibrils.

[085] After mechanical treatment, the nanocellulose material can be classified by particle size. A portion of the material may be subjected to a separate process, such as enzymatic hydrolysis to produce glucose. This material may have good crystallinity, for example, but may not have a desirable particle size or degree of polymerization.

[086] The process may additionally comprise treating cellulose-rich solids with one or more enzyme(s) or with one or more acid(s). When acids are employed, they may be selected from the group consisting of sulfur dioxide, sulfurous acid, lignosulfonic acid, acetic acid, formic acid and combinations thereof. Acids associated with hemicellulose, such as acetic acid or uronic acids, can be used, alone or together with other acids. Additionally, the process may include treating cellulose-rich solids with heat. In some embodiments, the process does not employ enzymes or acids.

[087] When an acid is used, the acid can be a strong acid, such as sulfuric acid, nitric acid or phosphoric acid, for example. Weaker acids can be used under more severe temperatures and/or time. Enzymes that hydrolyze cellulose (i.e., cellulases) and possibly hemicellulose (i.e., with hemicellulase activity) can be employed, instead of acids, or potentially in a sequential configuration before or after acid hydrolysis.

[088] In some embodiments, the process comprises enzymatically treating cellulose-rich solids to hydrolyze amorphous cellulose. In other embodiments, either sequentially before or after the enzymatic treatment, the process may comprise acid treating the cellulose-rich solids to hydrolyze the amorphous cellulose.

[089] In some embodiments, the process additionally comprises enzymatic treatment of crystalline cellulose. In other embodiments, either sequentially before or after enzymatic treatment, the process further comprises treating crystalline cellulose by acid treatment.

[090] If desired, an enzymatic treatment can be used before, or possibly simultaneously with, the mechanical treatment. However, in preferred embodiments, enzymatic treatment is not required to hydrolyze the amorphous cellulose or weaken the fiber wall structure prior to isolating the nanofibers.

[091] After mechanical treatment, nanolignocellulose can be recovered. The separation of cellulose nanofibrils and/or nanocrystals can be performed using a device capable of disintegrating the ultrastructure of the cell wall while preserving the integrity of the nanofibrils. For example, a homogenizer may be employed. In some embodiments, aggregated cellulose fibrils are recovered, having component fibrils in the range of 1-100 nm in width, wherein the fibrils have not been completely separated from each other.

[092] In some embodiments, the nanolignocellulose material is characterized by an average particle length and width aspect ratio of about 10 to about 1000, such as about 15, 20, 25, 35, 50, 75, 100, 150, 200, 250, 300, 400 or 500. Nanofibrils are generally associated with larger aspect ratios than nanocrystals. Nanocrystals, for example, can have a length range of about 100 nm to 500 nm and a diameter of about 1 to 10 nm. Nanofibrils can have a length of about 2000 nm and diameter range of 5 to 50 nm, translating to an aspect ratio of 40 to 400. In some embodiments, the aspect ratio is less than 50, less than 45 , less than 40, less than 35, less than 30, less than 25, less than 20, less than 15 or less than 10.

[093] Optionally, the process further comprises hydrolyzing amorphous cellulose into glucose, recovering the glucose, and fermenting the glucose into a fermentation product. Optionally, the process further comprises recovering, fermenting or further treating hemicellulosic sugars derived from part of the hemicellulose. Optionally, the process further comprises the recovery, combustion or further treatment of the lignin.

[094] The glucose that is generated from the hydrolysis of amorphous cellulose can be integrated into a general process to produce ethanol or another fermentation co-product. Thus, in some embodiments, the process further comprises hydrolyzing amorphous cellulose to glucose, and recovering the glucose. Glucose can be purified and sold. Or the glucose may be fermented to a fermentation product, such as, but not limited to, ethanol. Glucose or a fermentation product can be recycled to the input, such as for hemicellulose sugar processing, if desired.

[095] When hemicellulosic sugars are recovered and fermented, they can be fermented to produce a monomer or precursor thereof. The monomer can be polymerized to produce a polymer, which can then be combined with nanocellulose material to form a polymer-nanocellulose composite.

[096] In some embodiments, the process further comprises chemically converting the nanolignocellulose material into one or more nanolignocellulose derivative(s). For example, nanolignocellulose derivatives may be selected from the group consisting of nanolignocellulose esters, nanolignocellulose ethers, nanolignocellulose ether esters, alkylated nanolignocellulose compounds, cross-linked nanolignocellulose compounds, acid-functionalized nanolignocellulose compounds, acid-functionalized nanolignocellulose compounds. base, and combinations thereof.

[097] Various types of nanolignocellulose functionalization or derivation can be employed, such as functionalization using polymers, chemical surface modification, functionalization using nanoparticles (i.e., nanoparticles other than nanolignocellulose), modification with inorganics or surfactants or biochemical modification.

[098] High lignin loading rates have been achieved in thermoplastics. Even higher loading levels are obtained with well-known lignin modifications. The preparation of useful polymeric materials containing a substantial amount of lignin has been the subject of investigations for more than thirty years. Typically, lignin can be blended into polyolefins or polyesters by extrusion up to 25-40% by weight while satisfying the mechanical characteristics. In order to increase the compatibility between lignin and other hydrophobic polymers, different approaches have been used. For example, chemical modification of lignin can be carried out through esterification with long-chain fatty acids.

[099] A significant factor limiting the application of lightweight nanocellulose and enhancing strength in composites is the inherent hydrophilicity of cellulose. Modifying the surface of nanocellulose to impart hydrophobicity to enable uniform dispersion in a hydrophobic polymer matrix is an active area of study. It has been found that nanolignocellulose, as provided in the present invention, is hydrophobic.

[100] Optionally, the process for producing a hydrophobic nanolignocellulose material may further include chemically modifying the lignin to increase the hydrophobicity of the nanolignocellulose material. Any known chemical modifications can be performed on the lignin, to further increase the hydrophobic nature of the nanolignocellulose material provided by the embodiments of this invention.

[101] Some variations of the present invention are based on relatively simple processes for generating high viscosity compounds prepared from cellulosic biomass. High viscosity compounds act as rheological modifiers when mixed in small proportions with different fluids, such as drilling fluids, paints, etc.

[102] In hydraulic fracturing fluid formulations, particularly water-based formulations, but also for oil-based formulations, these compositions can function as gelling agents. Easy mixing and handling allow customization of each reservoir characteristic. Several properties of these rheology modifiers present strong advantages when compared to products currently available on the market. Some of these properties are: higher thermal stability, strong pesudoplasticity, thixotropic qualities and water solubility. Another important property of these new compounds is that they are biodegradable, and their production does not involve chemicals other than biomass and water.

[103] Some variations provide a process for producing a nanocellulose material, the process comprising: (a) providing a lignocellulosic biomass feedstock; (b) digesting the feedstock with a reaction solution including steam and/or hot water in a digester under effective reaction conditions to produce a digestate stream containing solids rich in cellulose, hemicellulose oligomers and lignin; (c) optionally washing the cellulose-rich solids to remove at least a portion of the hemicellulose oligomers and/or at least a portion of the lignin from the cellulose-rich solids; (d) mechanically treating the cellulose-rich solids to form a nanocellulose material containing cellulose nanofibrils and/or cellulose nanocrystals; and (e) recovering the nanocellulose material.

[104] The process may additionally include treating cellulose-rich solids with one or more enzyme(s) (e.g., cellulases) or with one or more acid(s), such as sulfur dioxide, sulfurous acid, acid lignosulfonic acid, acetic acid, formic acid or combinations thereof. The process may additionally include treating the cellulose-rich solids with heat. In some embodiments, steps (b)-(d) do not employ any externally added enzymes or acids.

[105] The nanocellulose material may include cellulose nanofibrils or a mixture of cellulose nanofibrils and cellulose nanocrystals. Figs. 1A-1C show SEM images of example experimentally produced nanocellulose by refining and homogenizing material produced from hot water extraction of biomass. The nanocellulose material may also include lignin, including lignin particles less than 1 micron in diameter. The process may include bleaching the cellulose-rich solids and/or bleaching the nanocellulose material after it is produced.

[106] In some embodiments, the process further comprises the recovery, fermentation or further treatment of hemicellulosic sugars derived from hemicellulose oligomers. For example, hemicellulosic sugars can be fermented to a fermentation product such as (but not limited to) ethanol.

[107] In some embodiments, the process further comprises hydrolyzing a portion of the cellulose-rich solids to glucose, recovering the glucose, and optionally fermenting the glucose into a fermentation product, such as n-butanol or 1 ,4-butanediol.

[108] The process may further include recovering, combusting or further treating the lignin that is washed from the cellulose-rich solids. Some or all of the initial lignin (in the initial feedstock) may become part of the nanocellulose material, which will be at least partially hydrophobic due to the presence of the lignin.

[109] In some embodiments, the process further comprises chemically converting the nanocellulose material into one or more nanocellulose derivative(s). For example, nanocellulose derivatives may be selected from the group consisting of nanocellulose esters, nanocellulose ethers, nanocellulose ether esters, alkylated nanocellulose compounds, cross-linked nanocellulose compounds, acid-functionalized nanocellulose compounds, base-functionalized nanocellulose compounds. , and combinations thereof.

[110] In certain embodiments, step (d) includes disc refining followed by homogenization of the cellulose-rich solids. Step (d), or a portion thereof, may be conducted with a solid consistency of at least 10% by weight, such as at least 20% by weight.

[111] The process includes, in some embodiments, exploding cellulose fibers contained in cellulose-rich solids. Fiber explosion can be achieved using steam explosion and/or rapid pressure reduction, for example. In certain embodiments, step (d) uses a blower line refiner, optionally with pressure reduction.

[112] Some variations of the invention provide a process for producing a biomass-derived rheology modifier from cellulosic biomass, the process comprising: (a) providing a feedstock comprising cellulosic biomass; (b) digesting the feedstock with a reaction solution including steam and/or hot water in a digester under effective reaction conditions to produce a digestate stream containing solids rich in cellulose, hemicellulose oligomers and lignin; (c) refining the cellulose-rich solids in a first high-intensity refining unit, thereby generating refined cellulose solids; (d) washing the refined cellulose solids after step (c) and/or washing the digested stream before step (c) followed by refining, thereby generating washed refined cellulose solids; (e) gelling the washed refined cellulose solids in a second high-intensity refining unit, thereby generating gelled cellulose solids; and (f) homogenizing the gelled cellulose solids in a high shear homogenizer, thereby generating a biomass-derived rheology modifier containing cellulose nanofibrils, cellulose nanocrystals, or a mixture of cellulose nanofibrils and cellulose nanocrystals.

[113] Optionally, the process further comprises wet or dry cleaning of the raw material before step (b). Optionally, regardless of whether the raw material is cleaned or not, the process further comprises reducing the size of the raw material before step (b).

[114] Step (b) can be conducted at a digestion temperature of about 140°C to about 210°C. Step (b) can be conducted for a digestion time of about 5 minutes to about 45 minutes. Step (b) can be conducted at a liquid/solid weight ratio of about 2 to about 6.

[115] The process may include a pressure reduction by hot or cold insufflation of the digested stream, after step (b).

[116] The first high-intensity refining unit may use discs or a conical plate, for example. In various embodiments, the first high-intensity refining unit transfers energy to the cellulose-rich solids in an amount of about 20 kW/ton to about 200 kW/ton (dry weight basis).

[117] Washing in step (d) can be conducted at a temperature of about 18°C to about 95°C. In some embodiments, washing in step (d) uses a pressurized screw press.

[118] The second high-intensity refining unit may use discs or a conical plate, for example. The first and second high-intensity refining units preferably have different patterns with different groove and dam dimensions. In various embodiments, the second high-intensity refining unit transfers energy to the washed refined cellulose solids in an amount of about 20 kW/ton to about 200 kW/ton (dry weight basis).

[119] In some embodiments, the high shear homogenizer transfers a shear force equivalent to a shear force produced under a pressure of about 10,000 psig (68.95 MPa man.) to about 25,000 psig (172. 37 MPa man.).

[120] In some embodiments, the washed refined cellulose solids are stored for a period of time before step (e). Step (e) may be performed in a different location than steps (a)-(d). Furthermore, step (f) may be performed in a different location than steps (a)-(e).

[121] Other variations of the invention provide a process for producing a biomass-derived rheology modifier from cellulosic biomass, the process comprising: (a) providing a pretreated feedstock comprising cellulose-rich solids; (b) refining the cellulose-rich solids in a first high-intensity refining unit, thereby generating refined cellulose solids; (c) optionally washing the refined cellulose solids after step (b) and/or optionally washing the digested stream before step (b) followed by refining, thereby generating washed refined cellulose solids; (d) gelling the washed refined cellulose solids in a second high-intensity refining unit, thereby generating gelled cellulose solids; and (e) homogenizing the gelled cellulose solids in a high shear homogenizer, thereby generating a biomass-derived rheology modifier containing cellulose nanofibrils.

[122] In some embodiments, the pretreated raw material is kraft cellulose pulp derived from wood or lignocellulosic biomass. In some embodiments, the pretreated feedstock is wood-derived sulfite cellulose pulp or lignocellulosic biomass. In some embodiments, the pretreated feedstock is wood-derived soda cellulose pulp or lignocellulosic biomass. In some embodiments, the pretreated raw material is mechanical cellulose pulp derived from wood or lignocellulosic biomass. In some embodiments, the pretreated raw material is thermomechanical pulp derived from wood or lignocellulosic biomass. In some embodiments, the pretreated raw material is chemomechanical cellulose pulp derived from wood or lignocellulosic biomass.

[123] Variations of the invention provide a water-based hydraulic fracturing fluid formulation or additive comprising (i) a nanocellulose material produced in accordance with a described process or (ii) a biomass-derived rheology modifier produced according to a process as described.

[124] Variations of the invention provide an oil-based hydraulic fracturing fluid formulation or additive comprising (i) a nanocellulose material produced in accordance with the described process or (ii) a biomass-derived rheology modifier produced from according to the process as described.

[125] Variations of the invention provide a water-based drilling fluid formulation or additive comprising (i) a nanocellulose material produced in accordance with the described process or (ii) a biomass-derived rheology modifier produced in accordance with with the described process.

[126] Variations of the invention provide an oil-based drilling fluid formulation or additive comprising (i) a nanocellulose material produced in accordance with the described process or (ii) a biomass-derived rheology modifier produced in accordance with the process described.

[127] Some variations provide a polymer-nanocellulose composite comprising (i) a nanocellulose material produced in accordance with the described process or (ii) a biomass-derived rheology modifier produced in accordance with the described process. Example polymers include, but are not limited to, polylactide, poly(vinyl alcohol), polyethylene, polypropylene, etc.

[128] In some embodiments, this process creates high viscosity compounds with sizes between 1 micron and 100 microns, such as between 15 microns and 50 microns. These new compounds produced without any chemicals (except biomass and water) can be used as rheological modifiers and, being based on cellulose, are completely biodegradable.

[129] The process has several advantages. The design allows the process to be fully integrated into one line from the start of biomass to the production of high viscosity compounds. Or the process can be separated into several modules that can be located in different geographic locations.

[130] The biomass feedstock can be selected from hardwoods, softwoods, forestry residues, agricultural residues (such as sugarcane bagasse), industrial residues, consumer residues or combinations thereof. In any of these processes, the raw material may include sucrose. In some embodiments with sucrose present in the raw material, the majority of the sucrose is recovered as part of the fermentable sugars.

[131] Some embodiments of the invention allow for the processing of “agricultural waste”, which for current purposes is intended to include lignocellulosic biomass associated with food crops, annual grasses, energy crops or other annually renewable feedstocks. Example agricultural residues include, but are not limited to, corn stover, corn fiber, wheat straw, sugar cane bagasse, rice straw, oat straw, barley straw, miscanthus, energy cane or combinations thereof. In certain embodiments, the agricultural residue is sugar cane bagasse, energy cane bagasse, sugar cane straw or energy cane straw.

[132] In some embodiments, the process further comprises wet or dry cleaning of the raw material before step (b). In some embodiments, the process further comprises reducing the size of the raw material prior to step (b). The process may include size reduction, hot water immersion, dehydration, steam treatment or other operations, upstream of the digester.

[133] Step (b) can be conducted at a digestion temperature of about 140°C to about 210°C, such as from about 175°C to about 195°C. Step (b) may be carried out for a digestion time of from about 5 minutes to about 45 minutes, such as from about 15 minutes to about 30 minutes. Step (b) may be conducted at a liquid/solid weight ratio of about 2 to about 6, such as about 3; 3.5; 4; 4.5 or 5.

[134] In some embodiments, the reaction solution comprises steam in saturated, superheated or supersaturated form. In some embodiments, the reaction solution comprises hot water.

[135] The pressure in the pressurized container can be adjusted to maintain the aqueous liquor as a liquid, a vapor, or a combination thereof. Example pressures are from about 1 atm to about 30 atm, such as about 3 atm, 5 atm, 10 atm, or 15 atm.

[136] The solid phase residence time for the digester (pressurized extraction vessel) can vary from about 2 minutes to about 4 hours, such as about 5 minutes to about 1 hour. In certain embodiments, the residence time of the digester is controlled at about 5 to 15 minutes, such as 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15 minutes. The liquid phase residence time for the digester can vary from about 2 minutes to about 4 hours, such as about 5 minutes to about 1 hour. The residence time in the vapor phase of the digester can vary from about 1 minute to about 2 hours, for example, such as about 3 minutes to about 30 minutes. Residence times in the solid phase, liquid phase, and vapor phase can be practically the same, or can be controlled independently according to reactor engineering principles (e.g., recycle and internal recirculation strategies).

[137] In some embodiments, the process further comprises a reduction in pressure by hot blowing of the digested stream, after step (b). Alternatively, a pressure reduction by cold insufflation of the digested stream, after step (b), can be employed.

[138] To reduce pressure, a blower tank can be situated between the digester and the refining unit. In some embodiments, the steam is separated from the inflation tank and heat is recovered from at least part of the steam. Optionally, at least part of the vapor is compressed and returned to the digester, and/or at least part of the vapor is purged from the process. Note that “blowback tank” should be broadly interpreted to include not just a tank, but any other appliance or equipment capable of permitting a pressure reduction in the process stream. Thus, an inflation tank (or inflation medium) may be a tank, vessel, section of pipe, valve, separation device or other unit.

[139] Each mechanical refiner may be selected from the group consisting of a hot blow refiner, a hot charge refiner, a disc refiner, a conical refiner, a cylindrical refiner, an in-line defibrator, a homogenizer, and combinations of the same. Mechanical treatment (refining) may employ one or more known technique(s), such as, but in no way limited to, grinding, crushing, beating, sonication or any other means to reduce the size of cellulose particles. These refiners are well known in the industry and include, without limitation, Valley beaters, single disc refiners, double disc refiners, conical refiners including wide angle and narrow angle, cylindrical refiners, homogenizers, microfluidizers and other similar grinding and crushing apparatus. . See, for example, Smook, Handbook for Pulp & Paper Technologists, Tappi Press, 1992.

[140] Refining can be conducted over a wide range of solids concentrations (consistency), including from about 2% to about 50% consistency, such as about 3%, 4%, 5%, 6% , 7%, 8%, 9%, 10%, 11%, 12%, 15%, 20%, 30%, 35% or 40% consistency.

[141] Each mechanical refiner can be configured to transfer from about 20 to about 200 kW/ton (i.e., refining power in kW per ton (1 ton = 907.18 kg) of fiber, based on the solid phase which is converted into the refined stream). In certain embodiments, the mechanical refiner is configured to transfer from about 75 to about 150 kW of refining power per ton of fiber. For example, a mechanical refiner with plates can be adjusted by changing the plate type, clearance, speed, etc. to obtain these power inputs.

[142] The extent of mechanical treatment can be monitored during the process by any of several means. Certain optical instruments can provide continuous data relating to fiber length distributions and % fines, one of which can be used to define end points for the mechanical treatment step. Time, temperature and pressure may vary during mechanical treatment. For example, in some embodiments, sonication for a time of about 5 minutes to 2 hours, at ambient temperature and pressure, can be used.

[143] In some embodiments, a portion of the cellulose-rich solids is converted to fibrillated and/or gelled, while the remainder of the cellulose-rich solids is not fibrillated and/or gelled. In various embodiments, about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 99% or substantially all of the cellulose-rich solids are fibrillated. and/or gelled.

[144] The first high-intensity refining unit may use discs or a conical plate, for example. In some embodiments, the first high-intensity refining unit transfers energy to the cellulose-rich solids in an amount of about 20 kW/ton (1 ton = 907.18 kg) to about 200 kW/ton (1 ton = 907.18 Kg) (dry weight basis), such as from about 75 kW/ton (1 ton = 907.18 Kg) to about 150 kW/ton (dry weight basis).

[145] In some embodiments, washing in step (d) is carried out at a temperature of from about 18°C to about 95°C, such as from about 70°C to about 80°C. Washing in step (d) may utilize a pressurized screw press.

[146] In some embodiments, the second high-intensity refining unit uses discs or a conical plate. The first and second high-intensity refining units preferably have different patterns with different groove and dam dimensions. In some embodiments, the second high-intensity refining unit transfers energy to the washed refined cellulose solids in an amount of from about 20 kW/ton (1 ton = 907.18 kg) to about 200 kW/ton ( 1 ton = 907.18 Kg) (dry weight basis), such as from about 75 kW/ton (1 ton = 907.18 Kg) to about 150 kW/ton (dry weight basis).

[147] In some embodiments, the high shear homogenizer (or other unit operation capable of imparting shear) transfers a shear force equivalent to a shear force produced under a pressure of about 1,000 psig (6.89 MPa man.) to about 50,000 psig (344.74 MPa man.), such as about 10,000 psig (68.94757 MPa man.) to about 25,000 psig (172.37 MPa man.).

[148] The washed refined cellulose solids can be stored for a period of time before step (e), which can be conducted in a location different from steps (a)-(d). In some embodiments, step (f) is not conducted at a location other than steps (a)-(e).

[149] In some embodiments, the biomass-derived rheology modifier may be characterized by a particle size (e.g., fiber or fibril length or effective length) of about 1 micron to about 100 microns, such as about 1 micron to about 50 microns. In certain embodiments, the majority (such as about 50%, 60%, 70%, 80%, 90% or 95%) of the particles are in the 10-15 micron size range. The biomass-derived rheology modifier may include particles smaller than 5 microns, such as 4, 3, 2, 1 micron(s) or less (i.e., nanoparticles). The width of the particles can be less than 1 micron. Particles larger than 100 microns, such as 150, 200, 250, 300, 400, 500 microns or more, may be present.

[150] In some embodiments, the biomass-derived rheology modifier may be characterized by a particle size (e.g., length or effective length) less than about 10 microns, such as about 9, 8, 7, 6, 5, 4, 3, 2, 1 micron(s) or less. In certain embodiments, the nanocellulose particle length is about 900, 800, 700, 600, 500, 400, 300, 200, 100 nm or less. In these or other embodiments (including lengths greater than 1 micron), the diameter of the nanocellulose particles may be from about 3 nm to about 1000 nm, from about 5 nm to about 500 nm, or from about 10 nm to about 200 nm or about 5, 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, 150, 200, 250, 300, 350, 400 or 450 nm . In some of these embodiments, the nanoparticles (or a portion thereof) can be characterized as nanocrystals.

[151] Rheology-modifying compounds are mainly cellulose-based polymers, with some microcrystalline form such as nanocellulose, including part of the initial biomass lignin in the structure. In some embodiments, the properties of the compound are predominantly hydrophilic, allowing strong stability of water-based drilling fluid and water-based fracturing fluids. In some embodiments with suitable lignin content and high-intensity refining, the compounds are hydrophobic, moderately hydrophobic, or a combination of hydrophilic and hydrophobic.

[152] The present disclosure provides a water-based hydraulic fracturing fluid formulation or additive comprising a biomass-derived rheology modifier produced in accordance with the processes described in the present invention.

[153] The present disclosure provides an oil-based hydraulic fracturing fluid formulation or additive comprising a biomass-derived rheology modifier produced in accordance with the processes described in the present invention.

[154] The present disclosure provides a water-based drilling fluid formulation or additive comprising a biomass-derived rheology modifier produced in accordance with the processes described in the present invention.

[155] The present disclosure provides an oil-based drilling fluid formulation or additive comprising a biomass-derived rheology modifier produced in accordance with the processes described in the present invention.

[156] The process may additionally include removing one or more fermentation inhibitor(s) (such as acetic acid or furfural) by removal. This removal can be accomplished by treating the hydrolyzed cellulose stream prior to fermentation. Alternatively, or additionally, removal may be conducted in a stream after digestion, such as in the insufflation line.

[157] The process in some embodiments additionally comprises a step of fermenting the fermentable sugars, contained in the liquid phase derived from the initial digestion, into a diluted fermentation product. The process may further comprise concentration and purification of the fermentation product. The fermentation product can be selected from ethanol, n-butanol, 1,4-butanediol, succinic acid, lactic acid or combinations thereof, for example. Additionally, a solid stream containing lignin can be removed, either before fermentation or downstream of fermentation.

[158] A step may include hydrolyzate conditioning to remove part or most of the volatile acids and other fermentation inhibitors. Evaporation may include flash evaporation or stripping to remove sulfur dioxide, if present, prior to removal of volatile acids. The evaporation step is preferably carried out below the acetic acid dissociation pH of 4.8, and more preferably a pH selected from about 1 to about 2.5. In some embodiments, additional evaporation steps may be employed. These additional evaporation steps can be conducted under different conditions (e.g., temperature, pressure, and pH) compared to the first evaporation step.

[159] In some embodiments, part of or all of the evaporated organic acids may be recycled, as vapor or condensate, to the first step (cooking step) to assist in the removal of hemicelluloses or minerals from the biomass. This recycling of organic acids, such as acetic acid, can be optimized along with process conditions that can vary depending on the amount recycled, to improve cooking effectiveness.

[160] A step may include the recovery of fermentable sugars, which may be stored, transported or processed. A step may include fermentation of the fermentable sugars into a coproduct (the primary product being a rheology modifier).

[161] A step may include preparing solid waste (containing lignin) for combustion. This step may include refining, grinding, fluidization, compaction and/or pelletization of the extracted and dried biomass. Solid waste can be fed to a reboiler in the form of fine powder, loose fiber, granules, briquettes, extrudates or any other suitable form. Using known equipment, solid waste can be extruded through a pressurized chamber to form uniformly sized granules or briquettes.

[162] After fermentation, residual solids (such as distillation bottom product) can be recovered, either burned in solid or slurry form, or recycled to be combined into biomass granules. The use of residual fermentation solids may additionally require mineral removal. Generally, any remaining solids can be used for burning after concentration of the distillation bottoms.

[163] Alternatively, or additionally, the process may include recovery of residual solids as a co-product of fermentation in solid, liquid or slurry form. The fermentation co-product can be used as a fertilizer or fertilizer component, as it will typically be rich in potassium, nitrogen and/or phosphorus.

[164] The process can be continuous, semi-continuous or batch. When continuous or semi-continuous, the removal column can be operated in countercurrent, concurrent or a combination thereof.

[165] The process may further comprise bleaching cellulose-rich solids prior to a refining step and/or as part of refining. Alternatively, or additionally, the process may further comprise bleaching the refined material, the gelled material or the homogenized material. Any known bleaching technology or sequence can be employed, including enzymatic bleaching.

[166] Rheology modifiers, as provided in the present invention, can be incorporated into drilling fluids, drilling fluid additives, fracturing fluids and fracturing fluid additives. Rheology modifiers may be present in a wide range of concentrations, such as from about 0.001% by weight to about 10% by weight or more, e.g., about 0.01% by weight, 0.05% by weight, weight, 0.1% by weight, 0.5% by weight, 1% by weight or 2% by weight.

[167] The invention, in some variations, is related to a group of cellulosic compounds that can be used in different applications. One application is to use them as drilling fluid product enhancers. Rheology modifiers can serve one or more functions in drilling fluids. For example, the rheology modifier may serve as a gelling agent to increase viscosity, or a viscosifier in general. The rheology modifier can serve as a friction reducer. Furthermore, rheology modifiers can be a drilling polymer, displacing other polymers or adding to them.

[168] Drilling fluids are fluids used in drilling in the natural gas and petroleum industries, as well as in other industries that use large drilling equipment. Drilling fluids are used to lubricate, provide hydrostatic pressure, keep the bit cool, and keep the hole as clean as possible from drill cuts. Rheology modifiers provided in the present invention are suitable as additives to such drilling fluids.

[169] In some embodiments, enzymes can be used as a “reducer” with the compositions to reduce rheology modifiers after some period of time or under certain conditions (e.g., temperature or pH).

[170] In some embodiments, lignosulfonates are incorporated to enhance lubrication in drilling applications. Furthermore, the ability of lignosulfonates to reduce the viscosity of mineral slurries may be beneficial in oil drilling muds.

[171] In some embodiments, native lignin or non-sulfonated lignin, or derivatives of non-sulfonated lignin, are incorporated into the compositions.

[172] Embodiments provide a drilling fluid additive comprising rheology modifiers.

[173] Some embodiments provide a drilling fluid additive comprising rheology modifiers, wherein the additive further comprises lignosulfonates.

[174] Some embodiments provide a drilling fluid additive comprising rheology modifiers, wherein the additive further comprises non-sulfonated lignin.

[175] Some embodiments provide a drilling fluid additive comprising rheology modifiers, wherein the additive further comprises a crosslinking agent.

[176] Some embodiments provide a drilling fluid additive comprising cross-linked rheology modifiers and lignosulfonates.

[177] Some embodiments provide drilling fluids comprising drilling fluid additives, as disclosed. The drilling fluid may be a water-based drilling fluid, an oil-based drilling fluid, or a water-based/oil-based hybrid drilling fluid.

[178] In various embodiments, the drilling fluid further comprises one or more of a biomass-derived weighting material, a biomass-derived filtration control agent, a biomass-derived rheology control agent, a biomass-derived pH control, a biomass-derived lost circulation material, a biomass-derived surface activity modifier, a biomass-derived lubricant, and a biomass-derived flocculant and/or a biomass-derived stabilizer.

[179] In some variations, the invention provides a method of using a drilling fluid additive, the method comprising combining a drilling fluid additive as disclosed in a base fluid to generate a drilling fluid. In some variations, the invention provides a method comprising introducing a disclosed drilling fluid additive directly or indirectly into a geological formation.

[180] In some variations, a drilling method includes introducing a drilling fluid additive directly or indirectly into a geological formation, wherein the drilling fluid additive includes an enzyme for degelation under effective conditions. In related variations, a drilling method includes introducing a drilling fluid additive directly or indirectly into a geological formation and subsequently introducing an enzyme for de-icing under effective conditions.

[181] Some variations provide a process for producing a drilling fluid additive, the process comprising refining biomass under effective pretreatment conditions and refining conditions to generate a drilling fluid additive, as disclosed. In some embodiments, effective pretreatment conditions include the generation of lignosulfonic acids. Optionally, at least a portion of the lignosulfonic acids is not removed and remains present in the drilling fluid additive. In certain embodiments, the drilling fluid additive comprises a liquid slurry derived from the process. For example, the slurry may contain biomass-derived rheological modifiers, as well as water and pretreatment chemicals (such as acids, solvents, etc.).

[182] Another application of these compositions is to use them as product enhancers of hydraulic fracturing fluids. The improvement in this purpose is mainly due to the impact on reduced friction, improved pumping of lifting agents at a higher rate, reduced pressure and predictable viscosity at high temperatures. Additionally, these products are completely biodegradable; they are produced from biomass, and are less susceptible to biofouling, as other products, such as galactomannan derivatives, could be.

[183] Rheology modifiers can be cross-linked for robust gelation in fracturing fluids. In some embodiments, cross-linking rheology modifiers results in a stronger gel with more hydration.

[184] Biomass-derived ash (from the biomass structure) or sand (from washing) can be used as a lifting agent to displace the mined silica.

[185] The present invention, in other variations, provides fracturing fluid additives.

[186] Some embodiments provide a fracturing fluid additive comprising rheology modifiers.

[187] Some embodiments provide a fracturing fluid additive comprising rheology modifiers, wherein the additive further comprises lignosulfonates.

[188] Some embodiments provide a fracturing fluid additive comprising rheology modifiers, wherein the additive further comprises non-sulfonated lignin.

[189] Some embodiments provide a fracturing fluid additive comprising rheology modifiers, wherein the additive further comprises a crosslinking agent.

[190] Some embodiments provide a fracturing fluid additive comprising cross-linked rheology modifiers and lignosulfonates.

[191] Some embodiments provide a fracturing fluid comprising the fracturing fluid additive, as disclosed. The fracturing fluid may be a water-based fracturing fluid, an oil-based fracturing fluid, or a hybrid water-based/oil-based fracturing fluid.

[192] The fracturing fluid may additionally include, in addition to a disclosed fracturing fluid additive, one or more of a biomass-derived acid (such as acetic acid, formic acid, levulinic acid and/or lignosulfonic acid), an inhibitor a biomass-derived corrosion inhibitor (such as lignin or a lignin derivative), a biomass-derived friction reducer (such as lignosulfonate or a lignosulfonate derivative), a biomass-derived clay control agent, a cross-linking agent derived from biomass, a biomass-derived scale inhibitor, a biomass-derived reducer, a biomass-derived iron control agent, a biomass-derived biocide (e.g., biomass hydrolyzate), and/or a biorefinery-derived source of recycled water or recovered. Typically, the fracturing fluid carries, includes, or must be combined with a lifting agent, which may be a biomass-derived lifting agent (such as ash contained in the biomass structure and/or sand, ash, or dirt collected with biomass). .

[193] Some variations of the invention provide a method of using a fracturing fluid additive, the method comprising combining a disclosed fracturing fluid additive into a base fluid to generate a fracturing fluid. Some methods include introducing a fracturing fluid additive directly or indirectly into a geological formation.

[194] In some variations, a process for producing a fracturing fluid additive comprises refining biomass under effective pretreatment conditions and refining conditions to generate a fracturing fluid additive, as disclosed. In some embodiments, pretreatment conditions include the generation of lignosulfonic acids, which are optionally not fully removed and are present in the fracturing fluid additive. In some embodiments, the fracturing fluid additive comprises a liquid slurry derived from the process. For example, the slurry may contain biomass-derived rheological modifiers, as well as water and pretreatment chemicals (e.g., solvents, acids, bases, and so on).

[195] The rheology modifiers of some embodiments are characterized by an average degree of cellulose polymerization of about 100 to about 2000, such as from about 400 to about 1200 or from about 500 to about 800 In certain embodiments, the rheology modifiers are enzyme-free.

[196] The present disclosure is in no way limited to rheology modifiers. The material produced by the multiple refining steps (after biomass pretreatment), as disclosed, can be used in a wide variety of applications. For example, the rheology modifier may be incorporated into the product selected from the group consisting of a structural object, a foam, an airgel, a polymer compound, a carbon compound, a film, a coating, a coating precursor, a current or voltage carrier, a filter, a membrane, a catalyst, a catalyst substrate, a coating additive, a paint additive, an adhesive additive, a cement additive, a paper coating, a thickening agent, a rheological modifier , an additive to a drilling fluid and combinations or derivatives thereof.

[197] Some embodiments provide products with applications for sensors, catalysts, antimicrobial materials, current energy transport and storage capabilities. Cellulose crystals have the ability to assist in the synthesis of metallic and semiconductor chains.

[198] Some embodiments provide composites containing refined cellulose and a carbon-containing material, such as (but not limited to) lignin, graphite, graphene or carbon aerogels.

[199] Cellulose crystals can be coupled with the stabilizing properties of surfactants and exploited to manufacture architectures of various semiconductor materials.

[200] The reactive surface of -OH side groups in refined cellulose facilitates the grafting of chemical species to obtain different surface properties. Surface functionalization allows tailoring of particle surface chemistry to facilitate self-assembly, controlled dispersion within a wide range of matrix polymers, and control of particle-particle and matrix-particle bond strength. Composites can be transparent, have greater tensile strength than cast iron, and have a very low coefficient of thermal expansion. Potential applications include, but are not limited to, barrier films, antimicrobial films, transparent films, flexible displays, reinforcing fillers for polymers, biomedical implants, dispensers for pharmaceuticals, pharmaceuticals, fibers and textiles, molds for electronic components, membranes. separation, batteries, supercapacitors, electroactive polymers and many others.

[201] Other suitable applications of the present invention include reinforced polymers, adhesives, high strength spunbond fibers and textiles, advanced composite materials, films for barrier and other properties, additives for coatings, paints, varnishes, adhesives, optical devices switchable materials, pharmaceuticals and drug dispensing systems, bone replacement and tooth repair, improved paper, packaging and construction products, food and cosmetic additives, catalysts and hydrogels.

[202] Aerospace and transportation composites can benefit from these rheology modifiers. Automotive applications include composites of cellulose with polypropylene, polyamide (e.g. Nylons) or polyesters (e.g. PBT).

[203] Rheology modifiers provided in the present invention can be suitable as additives to enhance the strength of renewable and biodegradable composites. Cellulosic fibrillar structures can function as a binder between two organic phases to improve fracture toughness and prevent crack formation for applications in packaging, construction materials, utensils, and renewable fibers.

[204] The rheology modifiers provided in the present invention can be additives and substrates that enhance dimensional stable and transparent resistance for application in flexible displays, flexible circuits, printable electronic components and flexible solar panels. Cellulose is incorporated into the substrate - sheets are formed by vacuum filtration, dried under pressure and calendered, for example. In a plate structure, cellulose acts as a glue between the filler aggregates. The calendered sheets formed are smooth and flexible.

[205] Rheology modifiers provided in the present invention can be suitable for composite and cement additives, allowing the reduction of cracks and greater toughness and resistance. Cellulose-concrete hybrid cellular and foamed materials enable lightweight structures with reduced cracking and increased strength.

[206] Strength enhancement with cellulose increases bond area and bond strength for high strength, high volume, high filler content paper and board applications with enhanced moisture and oxygen barrier properties. The cellulose pulp and paper industry, in particular, can benefit from the rheology modifiers provided in the present invention.

[207] Porous cellulose can be used for cellular bioplastics, insulation and plastics, and bioactive membranes and filters. Highly porous cellulose materials are generally of high interest in the manufacture of filtration media as well as for biomedical applications, for example in dialysis membranes.

[208] Rheology modifiers provided in the present invention can be suitable as additives to improve paint durability, protecting paints and varnishes from friction caused by UV radiation.

[209] Rheology modifiers provided in the present invention are suitable as thickening agents in food and cosmetic products. Rheology modifiers can be used as a thixotropic, biodegradable and dimensionally stable thickener (stable against temperature and salt addition). The rheology modifying materials provided in the present invention can be suitable as a Pickering stabilizer for emulsions and particle stabilized foam.

[210] The large surface area of these rheology modifiers in combination with their biodegradability makes them attractive materials for highly porous and mechanically stable aerogels.

[211] In some embodiments, the process comprises forming a structural object that includes the nanolignocellulose material, or a derivative thereof.

[212] In some embodiments, the process comprises forming a foam or airgel that includes nanolignocellulose material, or a derivative thereof.

[213] In some embodiments, the process comprises combining the nanolignocellulose material, or a derivative thereof, with one or more other materials to form a composite. For example, the other material may include a polymer selected from polyolefins, polyesters, polyurethanes, polyamides or combinations thereof. Alternatively, or additionally, the other material may include carbon in various forms.

[214] In some embodiments, the process comprises forming a film comprising nanolignocellulose material, or a derivative thereof. The film is optically transparent and flexible in certain embodiments.

[215] In some embodiments, the process comprises forming a coating or coating precursor comprising nanolignocellulose material, or a derivative thereof. In some embodiments, the nanolignocellulose-containing product is a paper coating.

[216] In some embodiments, the nanolignocellulose-containing product is configured as a catalyst, catalyst substrate or cocatalyst. In some embodiments, the nanolignocellulose-containing product is electrochemically configured to carry or store an electrical current or voltage.

[217] In some embodiments, the nanolignocellulose-containing product is incorporated into a filter, membrane or other separation device.

[218] In some embodiments, the nanolignocellulose-containing product is incorporated as an additive in a coating, paint or adhesive. In some embodiments, the nanolignocellulose-containing product is incorporated as a cement additive.

[219] In some embodiments, the nanolignocellulose-containing product is incorporated as a thickening agent or rheological modifier. For example, the nanolignocellulose-containing product may be an additive in a drilling fluid, such as (but not limited to) an oil recovery fluid and/or a gas recovery fluid or a fracturing fluid.

[220] A product containing nanolignocellulose can include any of the disclosed nanolignocellulose compositions. Many products containing nanolignocellulose are possible. For example, a product containing nanolignocellulose may be selected from the group consisting of a structural object, a foam, an airgel, a polymer composite, a carbon composite, a film, a coating, a coating precursor, a current carrier or voltage, a filter, a membrane, a catalyst, a catalyst substrate, a coating additive, a paint additive, an adhesive additive, a cement additive, a paper coating, a thickening agent, a rheological modifier, an additive for a drilling fluid and combinations or derivatives thereof.

[221] Certain products containing nanolignocellulose provide high transparency, good mechanical strength and/or enhanced gas barrier properties (e.g. O2 or CO2), for example. Certain nanolignocellulose-containing products containing hydrophobic nanocellulose materials provided in the present invention may be useful as anti-wetting and anti-freeze coatings, for example.

[222] Some embodiments provide products containing nanolignocellulose with applications for sensors, catalysts, antimicrobial materials, current transport capabilities and power storage.

[223] Some embodiments provide composites containing nanolignocellulose and a carbon-containing material, such as (but not limited to) lignin, carbon black, graphite, graphene or carbon aerogels.

[224] The reactive surface of -OH side groups on nanolignocellulose facilitates the grafting of chemical species to obtain different surface properties. Surface functionalization allows tailoring of particle surface chemistry to facilitate self-assembly, controlled dispersion within a wide range of matrix polymers, and control of particle-particle and matrix-particle bond strength. Composites can be transparent, have greater tensile strength than cast iron, and have a very low coefficient of thermal expansion. Potential applications include, but are not limited to, barrier films, antimicrobial films, transparent films, flexible displays, reinforcing fillers for polymers, biomedical implants, pharmaceutical dispensers, pharmaceuticals, fibers and textiles, molds for electronic components, membranes separation, batteries, supercapacitors, electroactive polymers and many others.

[225] Other applications of nanolignocellulose suitable for the present invention include reinforced polymers, high-strength spunbond fibers and textiles, advanced composite materials, films for barrier and other properties, additives for coatings, paints, varnishes and adhesives, optical devices switchable materials, pharmaceuticals and drug dispensing systems, bone replacement and tooth repair, improved paper, packaging and construction products, food and cosmetic additives, catalysts and hydrogels.

[226] Aerospace and automotive applications include nanolignocellulose composites with polypropylene, polyamide (e.g., Nylons) or polyesters (e.g., PBT).

[227] The nanolignocellulose materials provided in the present invention are suitable as additives to enhance the strength of renewable and biodegradable composites. Cellulosic nanofibrillar structures can function as a binder between two organic phases for improved fracture toughness and prevent crack formation for applications in packaging, construction materials, appliances, and renewable fibers.

[228] The nanolignocellulose materials provided in the present invention are suitable as additives and substrates that enhance transparent and dimensional resistance, for application in flexible displays, flexible circuits, printable electronic components, and flexible solar panels. Nanolignocellulose is incorporated into the substrate - the sheets are formed by vacuum filtration, dried under pressure and calendered, for example. In a sheet structure, nanocellulose acts as a glue between the filler aggregates. The calendered sheets formed are smooth and flexible.

[229] The nanolignocellulose materials provided in the present invention are suitable for composite and cement additives, allowing for reduced cracking and increased toughness and strength. Sparkling nanolignocellulose-concrete cellular hybrid materials, with reduced cracking and increased resistance.

[230] Strength enhancement with nanolignocellulose increases bond area and bond strength for high strength, high volume, high filler content paper and board applications with enhanced moisture and oxygen barrier properties. The pulp and paper industry, in particular, can benefit from the nanolignocellulose materials provided in the present invention.

[231] Nanofibrillated cellulose nanopaper has a higher density and tensile mechanical properties than conventional paper. It can also be optically transparent and flexible, with low thermal expansion and excellent oxygen barrier characteristics. The functionality of nanopaper can be further expanded by incorporating other entities, such as carbon nanotubes, nanoclays or a conductive polymer coating.

[232] Rojo et al., “Comprehensive elucidation of the effect of residual lignin on the physical, barrier, mechanical and surface properties of nanocellulose films,” Green Chem., 2015, 17, 1853-1866, is incorporated herein by reference in present invention.

[233] Porous nanolignocellulose can be used for cellular bioplastics, insulation and plastics, and bioactive membranes and filters. Highly porous materials are generally of high interest in the manufacture of filtration media as well as for biomedical applications, for example in dialysis membranes.

[234] The nanolignocellulose materials provided in the present invention are suitable as coating materials with oxygen barrier and affinity with wood fibers for application in food packaging and printing papers.

[235] The nanolignocellulose materials provided in the present invention are suitable as additives to improve paint durability, protecting paints and varnishes from friction caused by UV radiation.

[236] The nanolignocellulose materials provided in the present invention are suitable as thickening agents in food and cosmetic products. Nanolignocellulose can be used as a thixotropic, biodegradable and dimensionally stable thickener (stable against temperature and salt addition). The nanolignocellulose materials provided in the present invention are suitable as a Pickering stabilizer for emulsions and particle stabilized foam.

[237] The large surface area of these nanolignocellulose materials in combination with their biodegradability makes them attractive materials for highly porous and mechanically stable aerogels.

[238] The present invention also provides systems configured for carrying out the disclosed processes and compositions produced therefrom. Any stream generated by the disclosed processes may be partially or completely recovered, purified or further treated and/or marketed or sold.

[239] In this detailed description, reference has been made to various embodiments of the invention and to non-limiting examples relating to how the invention can be understood and practiced. Other embodiments that do not provide all of the features and advantages presented in the present invention may be used, without departing from the spirit and scope of the present invention. This invention incorporates routine experimentation and optimization of the methods and systems described in the present invention. Such modifications and variations are considered to be within the scope of the invention defined by the claims.

[240] All publications, patents and patent applications cited in this specification are incorporated herein by reference in their entirety, as if each publication, patent or patent application were specifically and individually set forth in the present invention.

[241] Where the methods and steps described above indicate certain events occurring in a certain order, those skilled in the art will recognize that the order of certain steps may be modified and that such modifications are in accordance with variations of the invention . Additionally, some of the steps can be executed simultaneously in a parallel process when possible, as well as executed sequentially.

[242] Therefore, to the extent that there are variations of the invention, which are within the spirit of the disclosure or equivalent to the inventions found in the appended claims, it is intended that this patent also covers these variations. The present invention should be limited only by what is claimed.

EXAMPLES Example 1: Nanolignocellulose Produced from Softwood.

[243] Softwood (pine) chips are processed in a pilot steam gun digester at a temperature of 185°C and 20 minutes, resulting in a cellulose pulp yield of about 80%. The cellulose pulp is passed through a pilot plant disc refiner to defibrillate the cooked chips at about 100 drain rate. The cellulose pulp drain rate provides a measure of the rate at which a diluted cellulose pulp suspension cellulose can be drained (see TAPPI T221 “Pulp Pulp Draining Time”). The cellulose pulp is then passed through a laboratory-scale homogenizer three times to a target of 80-85% fines, to produce unwashed nanolignocellulose. The percentage of fines (refined material) can be increased with more passes of the homogenizer. The unwashed nanolignocellulose is washed with water three times at 60°C for 30 min at about 2, 1 and 1 kg of water per kg of cellulose pulp, to produce washed nanolignocellulose.

[244] FIG. 2 shows an optical micrograph at 40x magnification of the washed nanolignocellulose produced in this example.

[245] The nanolignocellulose in this example is a combination of precipitated lignin particles (with diameters of about 50 to 300 nanometers), lignocellulose nanofibrils (with lengths of about 500 nanometers, widths of about 10 to 500 nanometers, and lengths of tens of microns), and lignocellulose fines (length <76 microns and width <5 microns).

[246] The washed solids are analyzed for composition. Total carbohydrates are about 66.8% by weight of solids. Glucan is 54% by weight, xylan is 9.2% by weight, galacatan is 1.3% by weight, arabinan is 0.6% by weight, and mannan is 1.7% by weight . The concentration of acetyl groups is 1.9% by weight in the solids. Total lignin is 35.8% by weight, of which 33.3% by weight (in solids) is Klason lignin and 2.5% by weight (in solids) is acid-soluble lignin.

[247] A liquid phase analysis shows 0.98 wt% glucose, 7.44 wt% xylose, 0.42 wt% galactose, 0.35 wt% arabinose, and 0.79 wt% weight of mannose, all sugars being a percentage of the original total solids (% in wood). Formic acid is 0.07% by weight, acetic acid is 0.28% by weight, HMF is 0.02% by weight, furfural is 0.02% by weight, and dissolved lignin is 1, 82% by weight, again being a percentage of the total original solids.

Example 2: Nanolignocellulose produced from Hardwood.

[248] Wood chips are processed in a pilot steam gun digester at a temperature of 185°C and 15 minutes, resulting in a cellulose pulp yield of about 80%. The cellulose pulp is passed through a pilot plant disc refiner to defibrillate the cooked chips at about 100 drain rate. The cellulose pulp is then passed through a laboratory-scale homogenizer three times to a target of 80 -85% fines, to produce unwashed nanolignocellulose. The percentage of fines (refined material) can be increased with more passes of the homogenizer. The unwashed nanolignocellulose is washed with water three times at 60°C for 30 min at about 2, 1 and 1 kg of water per kg of cellulose pulp, to produce washed nanolignocellulose.

[249] FIG. 3 shows an optical micrograph at 40x magnification of the washed nanolignocellulose produced in this example.

[250] The cellulose pulp produced in this example is also passed through the homogenizer 7 times, resulting in 92% fines. This is compared to bleached softwood Kraft cellulose pulp, refined by Masuko, 14 passes, 93% fines by area. FIG. 4 is a graph of the filtration rate of this nanolignocellulose compared to the prior art Kraft cellulose pulp. Filtration is Buchner filtration at 0.8% by weight total solids, with an initial volume of 450 mL (total available filtrate is 430 mL based on 17% total solids in the nanocellulose pad). The filter paper is Whatman 4 (pore size 20-25 μm).

[251] FIG. 4 shows a considerably higher filtration rate for this nanolignocellulose versus bleached Kraft fibrils. In particular, nanolignocellulose essentially has 100% filtration completion in less than 100 minutes. Due to the high lignin content, the water retention and drainage value of nanolignocellulose fibrils is much higher than that of pure cellulose fibrils. This is believed to be a key performance attribute for using nanolignocellulose in a paper machine.

Claims (11)

1. A nanolignocellulose composition characterized by at least 99% filtration completion in less than 100 minutes, wherein said nanolignocellulose composition comprises, on an ash-free and acetyl-free dry weight basis, from 35% by weight to 80% by weight cellulose nanofibrils, from 25% by weight to 35% by weight lignin, and from 7% by weight to 15% by weight hemicelluloses, wherein the cellulose nanofibrils are cellulose fibers containing particles or nanometer-sized fibers, wherein the nanometer-sized particles or fibers have at least one length dimension of 0.01 nm to 1000 nm, wherein the nanolignocellulose particles are closely associated with substantial amounts of lignin and hemicellulose. 2. Nanolignocellulose composition, according to claim 1, characterized by the fact that the percentage of lignin in the nanolignocellulose particles is 20%. 3. Nanolignocellulose composition according to claim 1, characterized by the fact that the percentage of hemicellulose in the nanolignocellulose particles is 5%. 4. Nanolignocellulose composition according to claim 1, characterized by the fact that said composition comprises from 40% by weight to 70% by weight of cellulose nanofibrils, on a dry weight, ash-free and carbon-free basis. acetyl. 5. Nanolignocellulose composition according to claim 1, characterized by the fact that said composition comprises from 45% by weight to 60% by weight of cellulose nanofibrils on a dry weight, ash-free and acetyl-free basis . 6. Nanolignocellulose composition according to claim 1, characterized by the fact that the nanolignocellulose material has an average particle length-width aspect ratio of 10 to 1000. 7. Nanolignocellulose composition according to claim 1, characterized by the fact that the nanofibrils have an aspect ratio of 40 to 400. 8. Nanolignocellulose composition according to claim 1, characterized by the fact that said composition comprises from 8% by weight to 14% by weight of hemicelluloses on a dry weight, ash-free and acetyl-free basis. 9. Nanolignocellulose composition according to claim 1, characterized by the fact that said hemicelluloses contain xylan as the main component. 10. Nanolignocellulose composition according to claim 1, characterized by the fact that said hemicelluloses contain mannan as the main component. 11. Cellulose pulp product or paper product characterized by the fact that it contains the nanolignocellulose composition as defined in claim 1.