WO2022087431A1

WO2022087431A1 - Method of dewatering cellulose

Info

Publication number: WO2022087431A1
Application number: PCT/US2021/056278
Authority: WO
Inventors: Scott TUDMAN
Original assignee: Sweetwater Energy, Inc.
Priority date: 2020-10-25
Filing date: 2021-10-22
Publication date: 2022-04-28

Abstract

In some aspects, calcium carbonate is mixed with an aqueous solution of cellulose or another hydrophilic polymer and then water is removed, leaving an unagglomerated calcium carbonate-cellulose mixture for storage, transport, or incorporation into products. This mixture is especially useful for increasing the tensile strength of cement or concrete.

Description

METHOD OF DEWATERING CELLULOSE

CROSS-REFERENCE

[0001] This application claims the benefit of U.S. Provisional Application No. 63/105,306, filed on October 25, 2020, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] The special features of cellulose polymers in the form of microcrystalline cellulose (MCC), nanocellulose (NFC), microfibrillated cellulose (MFC) and the like make them an interesting material for various industrial sectors, such as construction materials, pharmaceuticals, food products, and packaging. MCC is pure partially depolymerized cellulose synthesized from a-cellulose precursor. The MCC can be synthesized by different processes such as reactive extrusion, enzyme mediated, mechanical grinding, ultrasonication, steam explosion and acid hydrolysis. The later process can be done using mineral acids such as H2SO4, HC1 and HBr as well as ionic liquids. The role of these reagents is to destroy the amorphous regions leaving the crystalline domains.

[0003] Nanocellulose is a term referring to nano- structured cellulose. This may be either cellulose nanocrystal (CNC or NCC), cellulose nanofibers (CNF) also called nanofibrillated cellulose (NFC). CNF is a material composed of nanosized cellulose fibrils with a high aspect ratio (length to width ratio). Typical fibril widths are 5-20 nanometers with a wide range of lengths, typically several micrometers. It is pseudo-plastic and exhibits thixotropy, the property of certain gels or fluids that are thick (viscous) under normal conditions, but become less viscous when shaken or agitated. When the shearing forces are removed the gel regains much of its original state. The fibrils are isolated from any cellulose containing source including woodbased fibers (pulp fibers) through high-pressure, high temperature and high velocity impact homogenization, grinding or microfluidization.

[0004] Nanocellulose can also be obtained from native fibers by an acid hydrolysis, giving rise to highly crystalline and rigid nanoparticles which are shorter (100 to 1000 nanometers) than the cellulose nanofibrils (CNF) obtained through homogenization, microfluiodization or grinding routes.

[0005] One serious drawback to using cellulose filaments such as MCC is the difficulty of preparing dry cellulose filaments without decreasing their dispersibility in aqueous media and/or their reinforcement ability. This difficulty is similar to that for the drying of other cellulose microfibrils or nanofibrils or even pulp fibers or other hydrophilic polymers by conventional means, and is due to so-called agglomeration or homification. Homification is attributed to many factors that include: the formation of irreversible hydrogen bonds (H-bonds) and/or the formation of lactone bridges (Fernandes Diniz, et al., “Homification — its origin and interpretation in wood pulps,” Wood Sci Techno! . Vol. 37, 2004, pp. 489-494). Homification or agglomeration produces a dried polymer filament material that cannot be re-dispersed into water, a water solution or a water suspension, such as a pulp and paper suspension, when the dry cellulose filaments are mixed with wood pulps in a pulper or mixing for usage as a paper strengthening additive.

[0006] To avoid the disadvantage of irreversible agglomeration that produces non- dispersible microfibrillated cellulose (MFC) or nanofibrillated cellulose (NFC), two approaches have been attempted: 1) processing MFC with additives or 2) derivatizing MFC or NFC.

[0007] All these methods involve expensive chemicals and multi-step processing or are energy consuming, containing the use of excessive pressures or temperatures, which risk thermally or physically damaging the structure of the fibrillated nanocellulose material. In spite of the tedious operations of the known methods, the dewatering results will still be on an unsatisfactory basis and the nanocellulose may become at least partially aggregated.

SUMMARY

[0008] In one aspect, disclosed herein is a method of dewatering soluble polymers or hydrophilic polymers (polymer), comprising providing an aqueous suspension formed by a polymer in water; mixing the aqueous suspension with a drying agent to make a modified suspension comprising the polymer, wherein the drying agent is selected from the group consisting of: calcium carbonate, sodium bicarbonate, sodium carbonate, gypsum, potassium carbonate, calcium chloride, and any combination thereof; and physically removing water from the modified suspension to dewater the polymer.

[0009] In one aspect, disclosed herein is a method to increase tensile strength in concrete or cement, comprising: providing an aqueous suspension formed by a polymer in water; mixing the aqueous suspension with a drying agent to make a modified suspension comprising the polymer, wherein the drying agent is selected from the group consisting of: calcium carbonate, sodium bicarbonate, sodium carbonate, gypsum, potassium carbonate, calcium chloride, and any combination thereof; physically removing water from the modified suspension to dewater the polymer and produce a modified polymer product; and adding the modified polymer product to concrete or cement prior to curing.

[00010] In some embodiments, the polymer comprises microcrystalline cellulose (MCC). In some embodiments, the polymer comprises nanocellulose. In some embodiments, the nanocellulose is selected from the group consisting of: nanowhiskers, microfibrillated cellulose, nanocrystalline cellulose, nanofibrillated cellulose, and bacterial nanocellulose and combinations thereof. In some embodiments, the drying agent comprises calcium carbonate nanocrystals. In some embodiments, the calcium carbonate nanocrystals are derived from limestone, chalk, marble, travertine, shells, eggshells, calcite, aragonite, vaterite, calcium oxide, calcium hydroxide, or combinations thereof. In some embodiments, the calcium carbonate nanocrystals are mixed with the aqueous suspension in a ratio of 5% to 80%, 10% to 70%, 30% to 60%, or 40% to 50% CaCCh to polymer. In some embodiments, the water is removed from the modified suspension by centrifugation. In some embodiments, the water is removed from the modified suspension by filtration. In some embodiments, the water is removed from the modified suspension by evaporation. In some embodiments, the evaporation of the water from the modified suspension is carried out in a thin-film evaporator, a rotary evaporator, a falling film evaporator, a falling film evaporator, a thin film evaporator, a Kugelrohr evaporator, or a shorter long-path evaporator or a corresponding distillation device. In some embodiments, the method comprises removing at least 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90% of the water from the modified suspension. In some embodiments, the method comprises removing 20% to 90% of the water from the modified suspension. In some embodiments, the method comprises removing at least 90% of the water from the modified suspension. In some embodiments, the method comprises removing about 100% of the water from the modified suspension.

[00011] In some embodiments, the modified polymer product comprises the polymer and calcium carbonate. In some embodiments, the method results in reduction of the water content of the aqueous suspension by 20% to 90% or complete drying of the polymer. In some embodiments, the modified polymer product is added to the concrete or cement in a ratio of 0.01% to 25% of the concrete or cement by dry weight. In some embodiments, the modified polymer product is added to the concrete or cement in a suspension or dry.

BRIEF DESCRIPTION OF THE DRAWINGS

[00012] The novel features of the disclosure are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present disclosure will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the disclosure are utilized, and the accompanying drawings of which:

[00013] Figure 1 is a diagram depicting one embodiment for removing water from MCC or NFC with CaCCh and further potential processing steps. [00014] Figure 2 is a graph showing the difference in tensile strength between ordinary Portland cement (OPC) and Portland cement with the addition of MCC.

INCORPORATION BY REFERENCE

[00015] All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.

DETAILED DESCRIPTION

[00016] As used in the specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a purified monomer” includes mixtures of two or more purified monomers. The term “comprising” as used herein is synonymous with “including,” “containing,” or “characterized by,” and is inclusive or open-ended and does not exclude additional, unrecited elements or method steps.

[00017] “About” means a referenced numeric indication plus or minus 10% of that referenced numeric indication. For example, the term about 4 would include a range of 3.6 to 4.4. All numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth herein are approximations that can vary depending upon the desired properties sought to be obtained. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of any claims in any application claiming priority to the present application, each numerical parameter should be construed in light of the number of significant digits and ordinary rounding approaches.

[00018] Wherever the phrase “for example,” “such as,” “including” and the like are used herein, the phrase “and without limitation” is understood to follow unless explicitly stated otherwise. Therefore, “for example MCC production” means “for example and without limitation MCC production.

[00019] The term “biomass” as used herein has its ordinary meaning as known to those skilled in the art and can include one or more carbonaceous biological materials that can be converted into a biofuel, chemical or other product.

[00020] Biomass as used herein is synonymous with the term “feedstock” and includes silage, agricultural residues (corn stalks, grass, straw, grain hulls, bagasse, etc.), nuts, nut shells, coconut shells, animal waste (manure from cattle, poultry, and hogs), Distillers Dried Solubles, Distillers Dried Grains, Condensed Distillers Solubles, Distillers Wet Grains, Distillers Dried Grains with Solubles, woody materials (wood or bark, sawdust, wood chips, timber slash, and mill scrap), municipal waste (waste paper, recycled toilet papers, yard clippings, etc.), and energy crops (poplars, willows, switchgrass, alfalfa, prairie bluestem, algae, including macroalgae such as members of the Chlorophyta, Phaeophyta, Rhodophyta, etc.). One exemplary source of biomass is plant matter. Plant matter can be, for example, woody plant matter, non- woody plant matter, cellulosic material, lignocellulosic material, hemicellulosic material, sugar cane, grasses, switchgrass, rice, Spartina sp., sorghum, high biomass sorghum, bamboo, algae and material derived from these. Plants can be in their natural state or genetically modified, e.g., to increase the cellulosic or hemicellulosic portion of the cell wall, or to produce additional exogenous or endogenous enzymes to increase the separation of cell wall components. Plant matter can be further described by reference to the chemical species present, such as proteins, polysaccharides and oils.

[00021] Polysaccharides include polymers of various monosaccharides and derivatives of monosaccharides including glucose, fructose, lactose, galacturonic acid, rhamnose, etc. Plant matter also includes agricultural waste byproducts or side streams such as pomace, corn steep liquor, corncobs, corn fiber, corn steep solids, distillers’ grains, peels, pits, fermentation waste, straw, lumber, sewage, garbage and food leftovers. Peels can be citrus which include, but are not limited to, tangerine peel, grapefruit peel, orange peel, tangerine peel, lime peel and lemon peel. These materials can come from farms, forestry, industrial sources, households, etc. Another non-limiting example of biomass is animal matter, including, for example milk, bones, meat, fat, animal processing waste, and animal waste. “Feedstock” is frequently used to refer to biomass being used for a process, such as those described herein.

[00022] Nanocellulose can also be obtained from bacterial (“bacterial nanocellulose, BNC), for example bacteria of the strain Gluconacetobacter xylinus (also known as Acetobacter xylimtm). BNC has also been used for a variety of commercial applications including textiles, cosmetics, and food products, and it has a high potential for medical applications.

[00023] One of the major issues in utilizing specialty cellulose materials, such as MCC, NFC, and other cellulose materials is that when they are dried for shipment, they agglomerate by forming hydrogen bonds and the material does not disperse into the concrete mixture, greatly diminishing performance. It is extremely difficult to dewater these cellulose materials in their native state, so shipping and storage of large quantities becomes difficult due to the water content. Cellulose materials for use in such products can include nanowhiskers, microfibrillated cellulose, nanocrystalline cellulose, nanofibrillated cellulose, and bacterial nanocellulose and combinations thereof.

[00024] Described herein is a method to dewater the cellulose materials while preventing the hydrogen bonding and agglomeration of the material, allowing for effective, economical shipment and storage of the modified cellulose. It is estimated that, using this method, up to 90% or all of the water of the cellulose solution can be removed for large-scale commercial use, and that the cellulose remains useful for many applications. In one aspect, the water content of the aqueous cellulose suspension is reduced by 20% to 90% or completely dried.

[00025] For example, MCC, nanofibrillated cellulose, and other specialty cellulose materials have been shown to increase the strength of cement, mortar, and concrete applications. The methods described herein not only provide economical shipment of cellulose products but a method of easily incorporating them into concrete, thereby providing concrete strength enhancement.

[00026] An acid hydrolysis process described in US2016/0273009A1 is much faster and more effective than traditional pretreatment processes, and further processing steps remove other impurities such acids, sugars and other residues, yielding a refined clean cellulose and lignin. The sugars and sugar polymers from this process are cleaner can be used to make useful end-products such as MCC, NFC, biofuels, bioplastics and the like. Further, the homogenous and consistently small particle size of the starting material (ensuring the carbohydrate and lignin residues have a small particle size), are derived through the removal of the amorphous cellulose and hemicellulose.

[00027] The acid and steam explosion process described herein to extract biomass components is a rapid treatment process that releases over 80% of the lignin available in the feedstock. The treatment is carried out by reducing the particle size to small, uniform pieces of approximately 0.1 pm to 10 pm and further reducing the size as the particles are treated to pressurized acid hydrolysis and high temperatures, then subjected to steam explosion. Because the whole process is uniform throughout and only takes seconds, there is little inhibitor and ash formation in the resulting pretreated material. The yields of both carbohydrates, MCC, NFC, sugars and lignin are high.

[00028] A rapid pretreatment system using an extruder, such as described in US 2016/0273009 Al or WO2018/151833A1, each incorporated herein by reference in its entirety, offers a unique pathway for the deconstruction of biomass and release of lignin from other biomass components. The combination of mechanical fibrillation, dilute acid hydrolysis, and steam explosion, all accomplished in under 20 seconds, yields a very clean slurry of soluble sugars, microcrystalline cellulose, and lignin. The short, yet intense, treatment duration yields a unique cellulose product that has been rendered into a highly reactive state without the condensing or sulfonation that occurs in most other processes.

[00029] In the process system, a biomass feedstock is pretreated through an extruder system wherein the particle size of the biomass is reduced substantially, and the resulting product is subjected to uniform elevated temperature and pressure under acid conditions, then steam explosion also simultaneously. The C5 polymers and portions of the cellulose (C6 polymers) are hydrolyzed and separated from the pretreated stream. The pH in the resulting cellulose/lignin slurry is then elevated to solubilize the lignin which is then removed from the cellulose portion. The cellulose produced by this method is comprised of shorter fibers than other processes. It can be further purified and decolorized if necessary, for particular applications. Other methods to separate the lignin from MCC, NFC and other forms of cellulose can be used as well.

[00030] This method avoids multistep processing of MCC or NFC or other forms of cellulose.

[00031] In one aspect, disclosed herein is a method for commercial applications. In some embodiments, in a method disclosed herein, CaCCh can serve as a drying agent for MCC or NFC and can improve the chemistry of the product so that it is useful as a biopolymer reinforcing agent for direct incorporation in compounds such as concrete to make an improved product. The CaCCh can be derived from limestone, chalk, marble, travertine, shells, eggshells, calcite, aragonite, vaterite, calcium oxide, calcium hydroxide, or combinations thereof.

[00032] Other products that can be used for this purpose as a drying agent include hydrated lime, sodium bicarbonate, sodium carbonate, gypsum, potassium carbonate, and calcium chloride.

[00033] In one embodiment, this process precipitates nanocrystals of select minerals onto the surface of the specialty cellulose in order to reduce the overall water affinity of the cellulose and to facilitate the dewatering of the mineral-cellulose material without the formation of the cellulose-cellulose hydrogen bonds that cause the cellulose to agglomerate when dried. The nanocrystals of the mineral bind to the hydroxyl groups of the cellulose or other hydrophilic polymer.

[00034] In one example, the nanocrystals can be selected so that this component also further enhances the strength of concrete. For example, if calcium carbonate is the mineral chosen for this purpose, CaCCh nanocrystals have been shown to improve the hydration of cement, mortar, or concrete along with increasing compression strength. However, this product can also agglomerate when dried, thus cannot be added directly to concrete. See, U.S. Patent No. 9,492,945B2. Microcrystalline cellulose has been shown to increase the tensile strength of cement products (see Example 1 and Figure 2 infra), thus the combination of the specialty cellulose with the precipitated calcium carbonate nanocrystals can increase both tensile and compressive strength, making for a more robust final product.

[00035] Because calcium carbonate nanocrystals also show a tendency to agglomerate, reducing their effectiveness in applications, in one aspect, the deposition of the CaCCE nanocrystals onto the cellulose surface allows the cellulose to remain un-agglomerated when dehydrated, and also allows the calcium carbonate nanocrystals remain un-agglomerated, thereby increasing the overall effectiveness of both materials. In another aspect, other minerals, such as hydrated lime, and other common minerals typically incorporated into concrete can also be used for this application and can be tuned to generate varying enhancements to the final product. The mineral precipitation will also allow for the removal of water from the cellulose material using mechanical separation (filters, presses, centrifuges, etc.) or evaporation, greatly enhancing the transportability and storage of the material prior to end use. Evaporation of the water from the modified suspension can be carried out in a thin-film evaporator, a rotary evaporator, a falling film evaporator, a thin film evaporator, a Kugelrohr evaporator or a shorter long-path evaporator or a corresponding distillation device. In some embodiments, the moisture content of the cellulose material can be reduced from 80-85% in the raw cellulose to 20-30% or less moisture in the mineral-enhanced material.

[00036] Example 1

[00037] MCC paste at 14% total MCC solids was added to a cement mortar mixture at two different percentages to test for strength enhancements. See Table 1. The abbreviations w/c and a/c refer to the water to cement and aggregate to cement ratios, respectively. “OPC” refers to Ordinary Portland Cement. 170g of the MCC paste was added to the mixture, so there was a net addition of 23.8g of MCC on a dry basis. The results show the addition of 23.8g of MCC increased tensile strength (Figure 2). This is a 0.6% inclusion on a dry weight basis.

Table 1 w/c a/c MCC% MCC%/mix

0.5 3 2.5% 14%

OPC[g] Sand [g] MCC mix[g]

Control 1000 3000 0

1000 3000 179

Exemplary Embodiments Embodiment 1. A method to combine of dewatering soluble polymers or hydrophilic polymers (polymer), comprising:

(a) providing an aqueous suspension formed by a polymer in water;

(b) mixing the aqueous suspension with nanocrystals of CaCCE to make a modified suspension of CaCCE and polymer; and

(c) physically separating water from the modified suspension to dewater the polymer.

Embodiment 2. A method according to Embodiment 1, wherein the polymer is microcrystalline cellulose (MCC).

Embodiment 3. A method according to Embodiment 1, wherein the polymer is nanocellulose.

Embodiment 4. A method according to Embodiment 3, wherein nanocellulose is selected from the group consisting of: nanowhiskers, microfibrillated cellulose, nanocrystalline cellulose, nanofibrillated cellulose, and bacterial nanocellulose and combinations thereof.

Embodiment 5. A method according to Embodiment 1, wherein the CaCCE is derived from limestone, chalk, marble, travertine, shells, eggshells, calcite, aragonite, vaterite, calcium oxide, calcium hydroxide, or combinations thereof.

Embodiment 6. A method according to Embodiment 1, wherein the CaCCE is replaced by sodium bicarbonate, sodium carbonate, gypsum, potassium carbonate, and calcium chloride.

Embodiment 7. A method according to Embodiment 1, wherein the water is separated from the modified suspension by centrifugation.

Embodiment 8. A method according to Embodiment 1, wherein the water is separated from the modified suspension by filtration.

Embodiment 9. A method according to Embodiment 1, wherein the water is separated from the modified suspension by evaporation.

Embodiment 10. The method according to Embodiment 9, wherein the step of evaporation of water from the modified suspension is carried out in a thin-film evaporator, a rotary evaporator, a falling film evaporator, a falling film evaporator, a thin film evaporator, a Kugelrohr evaporator or a short- or long-path evaporator or a corresponding distillation device.

Embodiment 11. A method according to Embodiment 1, wherein the CaCCE is mixed with the polymer in a ratio of 5% to 80% CaCCE to polymer.

Embodiment 12. A method to increase tensile strength in concrete or cement, comprising:

(a) providing an aqueous suspension formed by a polymer in water;

(b) mixing the aqueous suspension with nanocrystals of CaCCE to make a modified suspension of CaCCE and polymer; (c) physically separating all or almost all the water from the modified suspension to dewater the polymer and produce a modified CaCCE-polymer product; and

(d) adding the CaCCE-polymer product to concrete or cement prior to curing.

Embodiment 13. A method according to Embodiment 12, wherein the polymer is microcrystalline cellulose (MCC).

Embodiment 14. A method according to Embodiment 12, wherein the polymer is nanocellulose.

Embodiment 15. A method according to Embodiment 14, wherein nanocellulose is selected from the group consisting of: nanowhiskers, microfibrillated cellulose, nanocrystalline cellulose, nanofibrillated cellulose, and bacterial nanocellulose and combinations thereof.

Embodiment 16. A method according to Embodiment 12, wherein the CaCCE is derived from limestone, chalk, marble, travertine, shells, eggshells, calcite, aragonite, vaterite, calcium oxide, calcium hydroxide, or combinations thereof.

Embodiment 17. A method according to Embodiment 12, wherein the CaCCE is replaced by sodium bicarbonate, sodium carbonate, gypsum, potassium carbonate, and calcium chloride.

Embodiment 18. A method according to Embodiment 12, wherein the water is separated from the modified suspension by centrifugation.

Embodiment 19. A method according to Embodiment 12, wherein the water is separated from the modified suspension by filtration.

Embodiment 20. A method according to Embodiment 12, wherein the water is separated from the modified suspension by evaporation.

Embodiment 21. The method according to Embodiment 20, wherein the step of evaporation of water from the modified suspension is carried out in a thin-film evaporator, a rotary evaporator, a falling film evaporator, a falling film evaporator, a thin film evaporator, a Kugelrohr evaporator or a short- or long-path evaporator or a corresponding distillation device.

Embodiment 22. A method according to Embodiment 12, wherein the CaCCE is mixed with the polymer in a ratio of 5% to 80% CaCCE to polymer.

Embodiment 23. A method according to Embodiment 12, wherein the water content of the aqueous suspension is reduced by 20% to 90% or completely dried.

Embodiment 24. A method according to Embodiment 12, wherein the CaCCE-polymer product is added to the concrete or cement in a ratio of 0.01% to 25% of the concrete or cement by dry weight. Embodiment 25. A method according to Embodiment 12, wherein the CaCCE-polymer product is added to the concrete or cement in a suspension or dry.

[1] A method of dewatering soluble polymers or hydrophilic polymers (polymer), comprising:

(a) providing an aqueous suspension formed by a polymer in water;

(b) mixing the aqueous suspension with a drying agent to make a modified suspension comprising the polymer, wherein the drying agent is selected from the group consisting of: calcium carbonate, sodium bicarbonate, sodium carbonate, gypsum, potassium carbonate, calcium chloride, and any combination thereof; and

(c) physically removing water from the modified suspension to dewater the polymer.

[2] The method according to paragraph [1], wherein the polymer comprises microcrystalline cellulose (MCC).

[3] The method according to paragraph [1], wherein the polymer comprises nanocellulose.

[4] The method according to paragraph [3], wherein the nanocellulose is selected from the group consisting of: nanowhiskers, microfibrillated cellulose, nanocrystalline cellulose, nanofibrillated cellulose, and bacterial nanocellulose and combinations thereof.

[5] The method according to any one of paragraphs [1 ]-[4], wherein the drying agent comprises calcium carbonate nanocrystals.

[6] The method according to paragraph [5], wherein the calcium carbonate nanocrystals are derived from limestone, chalk, marble, travertine, shells, eggshells, calcite, aragonite, vaterite, calcium oxide, calcium hydroxide, or combinations thereof.

[7] The method according to paragraph [5] or [6], wherein the calcium carbonate nanocrystals are mixed with the aqueous suspension in a ratio of 5% to 80%, 10% to 70%, 30% to 60%, or 40% to 50% CaCCE to polymer.

[8] The method according to any one of paragraphs [1 ]-[7], wherein the water is removed from the modified suspension by centrifugation.

[9] The method according to any one of paragraphs [1 ]-[7], wherein the water is removed from the modified suspension by filtration.

[10] The method according to any one of paragraphs [1 ]-[7], wherein the water is removed from the modified suspension by evaporation.

[11] The method according to paragraph [10], wherein the evaporation of the water from the modified suspension is carried out in a thin-film evaporator, a rotary evaporator, a falling film evaporator, a falling film evaporator, a thin film evaporator, a Kugelrohr evaporator, or a short- or long-path evaporator or a corresponding distillation device. [12] The method according to any one of paragraphs [1 ]-[ 11], wherein the method comprises removing at least 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90% of the water from the modified suspension.

[13] The method according to any one of paragraphs [1]-[11], wherein the method comprises removing 20% to 90% of the water from the modified suspension.

[14] The method according to any one of paragraphs [1]-[11], wherein the method comprises removing at least 90% of the water from the modified suspension.

[15] The method according to any one of paragraphs [1]-[11], wherein the method comprises removing about 100% of the water from the modified suspension.

[16] A method to increase tensile strength in concrete or cement, comprising:

(a) providing an aqueous suspension formed by a polymer in water;

(b) mixing the aqueous suspension with a drying agent to make a modified suspension comprising the polymer, wherein the drying agent is selected from the group consisting of: calcium carbonate, sodium bicarbonate, sodium carbonate, gypsum, potassium carbonate, calcium chloride, and any combination thereof;

(c) physically removing water from the modified suspension to dewater the polymer and produce a modified polymer product; and

(d) adding the modified polymer product to concrete or cement prior to curing.

[17] The method according to paragraph [16], wherein the polymer comprises microcrystalline cellulose (MCC).

[18] The method according to paragraph [16], wherein the polymer comprises nanocellulose.

[19] The method according to paragraph [18], wherein the nanocellulose is selected from the group consisting of: nanowhiskers, microfibrillated cellulose, nanocrystalline cellulose, nanofibrillated cellulose, and bacterial nanocellulose and combinations thereof.

[20] The method according to any one of paragraphs [16]-[l 9], wherein the drying agent comprises calcium carbonate nanocrystals.

[21] The method according to paragraph [20], wherein the calcium carbonate nanocrystals are derived from limestone, chalk, marble, travertine, shells, eggshells, calcite, aragonite, vaterite, calcium oxide, calcium hydroxide, or combinations thereof.

[22] The method according to paragraph [20] or [21], wherein the calcium carbonate nanocrystals are mixed with the polymer in a ratio of 5% to 80%, 10% to 70%, 30% to 60%, or 40% to 50% CaCCh to polymer.

[23] The method according to any one of paragraphs [20]-[22], wherein the modified polymer product comprises the polymer and calcium carbonate. [24] The method according to any one of paragraphs [16]-[23], wherein the method comprises removing at least 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90% of the water from the modified suspension.

[25] The method according to any one of paragraphs [16]-[23], wherein the method comprises removing 20% to 90% of the water from the modified suspension.

[26] The method according to any one of paragraphs [16]-[23], wherein the method comprises removing at least 90% of the water from the modified suspension.

[27] The method according to any one of paragraphs [16]-[23], wherein the method comprises removing about 100% of the water from the modified suspension.

[28] The method according to any one of paragraphs [16]-[27], wherein the water is removed from the modified suspension by centrifugation.

[29] The method according to any one of paragraphs [16]-[27], wherein the water is removed from the modified suspension by filtration.

[30] The method according to any one of paragraphs [16]-[27], wherein the water is removed from the modified suspension by evaporation.

[31] The method according to paragraph [30], wherein the evaporation of the water from the modified suspension is carried out in a thin-film evaporator, a rotary evaporator, a falling film evaporator, a falling film evaporator, a thin film evaporator, a Kugelrohr evaporator, or a short- or long-path evaporator or a corresponding distillation device.

[32] The method according to any one of paragraphs [16]-[31], wherein method results in reduction of the water content of the aqueous suspension by 20% to 90% or complete drying of the polymer.

[33] The method according to any one of paragraphs [16]-[32], wherein the modified polymer product is added to the concrete or cement in a ratio of 0.01% to 25% of the concrete or cement by dry weight.

[34] The method according to any one of paragraphs [16]-[33], wherein the modified polymer product is added to the concrete or cement in a suspension or dry.

[00038] While preferred embodiments of the present disclosure have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the disclosure. It should be understood that various alternatives to the embodiments of the disclosure described herein may be employed in practicing the disclosure. It is intended that the following claims define the scope of the disclosure and that methods and structures within the scope of these claims and their equivalents be covered thereby.

Claims

WHAT IS CLAIMED IS: . A method of dewatering soluble polymers or hydrophilic polymers (polymer), comprising:

(a) providing an aqueous suspension formed by a polymer in water;

(c) physically removing water from the modified suspension to dewater the polymer. . The method according to claim 1, wherein the polymer comprises microcrystalline cellulose (MCC). . The method according to claim 1, wherein the polymer comprises nanocellulose. . The method according to claim 3, wherein the nanocellulose is selected from the group consisting of: nanowhiskers, microfibrillated cellulose, nanocrystalline cellulose, nanofibrillated cellulose, and bacterial nanocellulose and combinations thereof. . The method according to claim 1, wherein the drying agent comprises calcium carbonate nanocrystals. . The method according to claim 5, wherein the calcium carbonate nanocrystals are derived from limestone, chalk, marble, travertine, shells, eggshells, calcite, aragonite, vaterite, calcium oxide, calcium hydroxide, or combinations thereof. . The method according to claim 5 or 6, wherein the calcium carbonate nanocrystals are mixed with the aqueous suspension in a ratio of 5% to 80%, 10% to 70%, 30% to 60%, or 40% to 50% CaCCh to polymer. . The method according to claim 1, wherein the water is removed from the modified suspension by centrifugation. . The method according to claim 1, wherein the water is removed from the modified suspension by filtration. 0. The method according to claim 1, wherein the water is removed from the modified suspension by evaporation. 1. The method according to claim 10, wherein the evaporation of the water from the modified suspension is carried out in a thin-film evaporator, a rotary evaporator, a falling film evaporator, a falling film evaporator, a thin film evaporator, a Kugelrohr evaporator, or a short- or long-path evaporator or a corresponding distillation device. The method according to claim 1, wherein the method comprises removing at least 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90% of the water from the modified suspension. The method according to claim 1, wherein the method comprises removing 20% to 90% of the water from the modified suspension. The method according to claim 1, wherein the method comprises removing at least 90% of the water from the modified suspension. The method according to claim 1, wherein the method comprises removing about 100% of the water from the modified suspension. A method to increase tensile strength in concrete or cement, comprising:

(a) providing an aqueous suspension formed by a polymer in water;

(b) mixing the aqueous suspension with a drying agent to make a modified suspension comprising the polymer, wherein the drying agent is selected from the group consisting of calcium carbonate, sodium bicarbonate, sodium carbonate, gypsum, potassium carbonate, calcium chloride, and any combination thereof;

(d) adding the modified polymer product to concrete or cement prior to curing. The method according to claim 16, wherein the polymer comprises microcrystalline cellulose (MCC). The method according to claim 16, wherein the polymer comprises nanocellulose. The method according to claim 18, wherein the nanocellulose is selected from the group consisting of nanowhiskers, microfibrillated cellulose, nanocrystalline cellulose, nanofibrillated cellulose, and bacterial nanocellulose and combinations thereof. The method according to claim 16, wherein the drying agent comprises calcium carbonate nanocrystals. The method according to claim 20, wherein the calcium carbonate nanocrystals are derived from limestone, chalk, marble, travertine, shells, eggshells, calcite, aragonite, vaterite, calcium oxide, calcium hydroxide, or combinations thereof. The method according to claim 20 or 21, wherein the calcium carbonate nanocrystals are mixed with the polymer in a ratio of 5% to 80%, 10% to 70%, 30% to 60%, or 40% to 50% CaCCh to polymer. The method according to claim 20, wherein the modified polymer product comprises the polymer and calcium carbonate. The method according to claim 16, wherein the method comprises removing at least 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90% of the water from the modified suspension. The method according to claim 16, wherein the method comprises removing 20% to 90% of the water from the modified suspension. The method according to claim 16, wherein the method comprises removing at least 90% of the water from the modified suspension. The method according to claim 16, wherein the method comprises removing about 100% of the water from the modified suspension. The method according to claim 16, wherein the water is removed from the modified suspension by centrifugation. The method according to claim 16, wherein the water is removed from the modified suspension by filtration. The method according to claim 16, wherein the water is removed from the modified suspension by evaporation. The method according to claim 30, wherein the evaporation of the water from the modified suspension is carried out in a thin-film evaporator, a rotary evaporator, a falling film evaporator, a falling film evaporator, a thin film evaporator, a Kugelrohr evaporator, or a short- or long-path evaporator or a corresponding distillation device. The method according to claim 16, wherein method results in reduction of the water content of the aqueous suspension by 20% to 90% or complete drying of the polymer. The method according to claim 16, wherein the modified polymer product is added to the concrete or cement in a ratio of 0.01% to 25% of the concrete or cement by dry weight. The method according to claim 16, wherein the modified polymer product is added to the concrete or cement in a suspension or dry.

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