Wood-derived lignin composition

Abstract

A wood-derived lignin composition is disclosed, which contains, based on the total dry matter of the lignin composition, 80-90 wt. % of acid-insoluble lignin having an average molecular weight of 5,000-15,000 Da, 1.5-15 wt. % carbohydrates, and 0.2-1.5 wt. % nitrogen, and the weight ratio of oxygen to carbon is at least 0.5. Furthermore, a method for producing the wood-derived lignin composition is disclosed.

Description

[Technical Field]

[0001] This disclosure relates to wood-derived lignin compositions and their uses. This disclosure further relates to methods for producing wood-derived compositions. [Background technology]

[0002] Various methods are known for converting bio-based raw materials, such as lignocellulosic biomass, into liquid flows of various components. Providing a sufficiently pure lignin composition with properties suitable for further applications remains a challenge for researchers. [Overview of the project]

[0003] A wood-derived lignin composition is disclosed. The wood-derived lignin composition may contain 80-90% by weight of acid-insoluble lignin with an average molecular weight of 5000-15000 Da, 1.5-15% by weight of carbohydrates, and 0.2-1.5% by weight of nitrogen, based on the total dry matter content of the lignin composition, and the weight ratio of oxygen to carbon is at least 0.5.

[0004] Furthermore, a method for producing a wood-derived lignin composition is disclosed. The method may include the following steps. i) (Step i)) A step of preparing a wood-based raw material containing wood chips derived from wood-based raw materials, and pre-treating the wood-based raw material to form a fraction containing solid cellulose particles. Here, the total dry matter content of the fraction containing the solid cellulose particles is 8 to 20% by weight, and up to 3% by weight of the wood shives in the fraction containing the solid cellulose particles has a width greater than 1 mm as determined by the Somerville method. ii) (Step ii)) Enzymatic hydrolysis of the fraction containing the solid cellulose particles from step i) (Enzyme hydrolysis process) A process to carry out the following. Here, the enzyme hydrolysis step is iia) (Stage iia)) For the fraction containing the solid cellulose particles, the first enzymatic hydrolysis step is performed for 8 to 72 hours. (First enzymatic hydrolysis step) A step to produce the first hydrolysis product by performing the following (step) and, iib) (Stage iib)) First solid-liquid separation process (First solid-liquid separation process) This process separates the first hydrolysis product into a solid fraction containing lignin and a liquid carbohydrate fraction. (step) and, iic) (Stage iic)) A step of mixing the solid fraction containing the lignin separated in step iib) with a liquid to re-form a slurry. (step) and, iid) (stage iid)) The solid fraction containing the re-slurried lignin is subjected to a second enzymatic hydrolysis step for 8 to 72 hours. (Second enzymatic hydrolysis step) A step to produce a second hydrolysis product. (step) and, No) (Stage II)) Second solid-liquid separation process (Second solid-liquid separation process) This process separates the second hydrolysis product into a solid fraction containing lignin and a liquid carbohydrate fraction. (step) This includes. iii) (Step iii)) A step of obtaining the lignin composition by performing at least one purification step on the solid fraction containing the lignin obtained from the enzymatic hydrolysis step of step ii).

[0005] Furthermore, wood-derived lignin compositions obtained by the methods disclosed herein are also disclosed.

[0006] Furthermore, applications of the wood-derived lignin compositions disclosed herein for the manufacture of composites, fillers, adhesives, paints, or resins are disclosed.

[0007] The accompanying drawings included to provide a further understanding of the embodiments and to constitute part of this specification illustrate one embodiment.

Brief Description of the Drawings

[0008] [Figure 1] A flowchart of an embodiment of a method for producing a lignin composition derived from wood is shown.

Modes for Carrying Out the Invention

[0009] A lignin composition derived from wood is disclosed. The lignin composition derived from wood may contain 80 to 90% by weight of acid-insoluble lignin having an average molecular weight of 5000 to 15000 Da, 1.5 to 15% by weight of carbohydrates, and 0.2 to 1.5% by weight of nitrogen, based on the total dry matter of the lignin composition. And the weight ratio of oxygen to carbon thereof is at least 0.5.

[0010] Furthermore, a method for producing a lignin composition derived from wood is disclosed. The method may include the following steps. i) Prepare a wood-based raw material derived from a wood-based raw material containing wood chips, and pretreat the wood-based raw material to form a fraction containing solid cellulose particles. Here, the total dry matter of the fraction containing solid cellulose particles is 8 to 20% by weight, and at most 3% of the wood shives in the fraction containing solid cellulose particles have a width determined by the Somerville method of more than 1 mm. ii) Perform an enzymatic hydrolysis step on the fraction containing the solid cellulose particles in step i). Here, the enzymatic hydrolysis step is iia) Perform a first enzymatic hydrolysis step on the fraction containing the solid cellulose particles for 8 to 72 hours to produce a first hydrolysis product. iib) Separate the first hydrolysis product into a solid fraction containing lignin and a liquid carbohydrate fraction by a first solid-liquid separation step. iic) Mix the solid fraction containing lignin separated in step iib) with a liquid to re-slurry. iid) subjecting the solid fraction containing the reslurried lignin to a second enzymatic hydrolysis step for 8 to 72 hours to produce a second hydrolysis product; iie) separating the second hydrolysis product into a solid fraction containing lignin and a liquid carbohydrate fraction by a second solid-liquid separation step. iii) obtaining the lignin composition by performing at least one purification step on the solid fraction containing lignin from the enzymatic hydrolysis step of step ii).

[0011] Furthermore, a lignin composition derived from wood obtained by the method disclosed herein is disclosed. In one embodiment, the lignin composition derived from wood obtained by the method disclosed herein is the lignin composition derived from wood disclosed herein. That is, the lignin composition derived from wood disclosed herein can be produced by the method disclosed herein.

[0012] Also disclosed is the use of the lignin composition derived from wood disclosed herein for producing a composite, a filler, an adhesive, a paint or a resin.

[0013] As used herein, the "Somerville method" conforms to standard Tappi T 275 sp-07 and has the following deviations. According to Tappi T 275 sp-07, the amount of sample added onto the flat screen is 50 g of oven-dried sample. In the "Somerville method" used herein, 50 g of sample (total solids) is added onto a Somerville 1.0 mm screen after cold disintegration, but the total suspended solid content in the sample depends on the amount of soluble components in the sample. Measurement by the Somerville method can be performed by weighing the original wet sample, obtaining 50 g of dry sample (TS), and cold dispersing it. Cold dispersion can be performed as follows.

[0014] A wet sample, calculated as 50g of oven-dryable material, is transferred to a dispersion cup, and water at 20±5°C is added to make a dispersion volume of 2000ml. The total dry matter (total solids TS) of the sample is measured in an oven at 60°C, and the total suspended solids are measured based on the following: The solid content of the sample is measured as the amount of solid material relative to the total dry matter (amount of solids + soluble matter). A warm slurry (approximately 50°C) with approximately 7% total suspended solids (often equivalent to ~10% total solids) is prepared, and extraction is carried out for 30 minutes while stirring. The formed slurry is filtered to wash away the solids from the cake. When the sample is filtered in this way, only solids remain in the filter. The sample is filtered using pre-weighed filter paper. If necessary, the filtrate can be collected and stored, and the filtered cake can be washed three times with a large amount of warm tap water (approximately 50°C). This cake is dried overnight or longer in an oven at 60°C or higher (dried to a constant weight). The sample concentration of solids is calculated using the following formula.

[0015]

number

[0016] The amount of sample required for analysis is calculated based on the total solid content.

[0017] After cold decay, a 1.0 mm flat screen is prepared. All of the dispersed sample (cold decay) is passed onto the 1.0 mm sieve, and the timer is started. The process is completed after 20 minutes. The flat screen is transferred to a collection container, and the sieve is carefully rinsed to remove all traces of sieve. Any sieve remaining on the sieve is washed onto pre-weighted filter paper. The sieve is dried overnight in a drying oven at 105°C ± 2°C. The sieve is cooled in a desiccator and weighed to an accuracy of 1 mg.

[0018] The amount of shavings can then be calculated as a percentage of the dry weight of the added suspended solids. Sommerville (primary shave) % = m(shave + filter paper) - m(filter paper) mTSS * 100, where, Somarvir (primary shave) = Somarvir primary shave content, m(shave + filter paper) = weight of shave and filter paper, in grams. m (filter paper) = weight of filter paper, g, mTSS = Total Suspension Solids of a sample dried in an oven (60°C), expressed in grams. mTSS can be calculated (TSS%) when the percentage of suspended solids in a sample is known, as it measures the total suspended solids based on the method described above. mTSS = msamples × TSS%, m sample = weight of the sample for Somarvil analysis, in grams. SS% = Total suspended solid content of the sample, expressed in percent.

[0019] The wood-derived lignin compositions disclosed herein relate to compositions containing lignin, but may also contain other components and / or elements as disclosed herein. Therefore, the "wood-derived lignin composition" can be considered as either a "wood-derived composition containing lignin" or a "wood-derived composition containing lignin."

[0020] In this specification, the amounts of each component / element in the wood-derived lignin composition are expressed in weight percent based on the total dry matter content of the lignin composition. In this specification, "total dry matter content of the lignin composition" refers to the weight of the lignin composition obtained after removing the liquid and drying it at 105°C for 24 hours. The effectiveness of liquid removal can be evaluated by weighing the sample, drying it at a predetermined temperature for 2 hours, and then weighing it again. If the measured weights are the same, the total weight may be recorded as the drying is complete.

[0021] As will be apparent to those skilled in the art, the total amount of each component / element in the wood-derived lignin composition does not need to exceed 100% by weight. The weight percentage of each component / element in the wood-derived lignin composition may vary within a predetermined range.

[0022] In one embodiment, a lignin composition is provided that contains 0.5 to 6% by weight, or 0.75 to 4% by weight, or 1 to 3% by weight, or 1.5 to 2% by weight of a soluble component.

[0023] In this way, the lignin composition can be obtained by performing an enzymatic hydrolysis step on a fraction containing solid cellulose particles.

[0024] The inventors have surprisingly found that the method disclosed herein can provide a wood-derived lignin composition in which the content of soluble components may be as low as 2% by weight, for example, less than 1% by weight. That is, the method disclosed herein has the added utility of enabling the production of a high-purity lignin composition.

[0025] In one embodiment, the lignin composition contains 0.5 to 2.5% by weight, or 1 to 2% by weight, of acid-soluble lignin based on the total dry matter content of the lignin composition. The amount of acid-soluble lignin can be determined in accordance with the TAPPI UM 250 standard.

[0026] In one embodiment, the lignin composition contains 80-90% by weight, or 82-90% by weight, or 84-90% by weight, or 87-90% by weight, or 88-90% by weight, of acid-insoluble lignin, based on the total dry matter amount of the lignin composition.

[0027] The amount of acid-insoluble lignin can be determined according to the modified standard of TAPPI T 222. Specifically, the amount of acid-insoluble lignin can be measured gravimetrically by filtration using the following method: The sample is treated in a water bath with 72% sulfuric acid at a constant temperature (30°C) for 1 hour, and then autoclaved at 120°C and 1 bar for 1 hour. The acid precipitates the lignin, which can then be determined gravimetrically. The precipitated lignin is separated by vacuum filtration of the sample. The acid-insoluble lignin content in the sample can then be calculated using the following formula.

[0028]

number

[0029] In one embodiment, the average molecular weight of the lignin is 5500 to 12000 Da, or 6000 to 10000 Da. The average molecular weight can be determined by size exclusion chromatography (SEC) using 0.1 M NaOH as the eluent, with a sample volume of approximately 1 mg / ml dissolved in 0.1 M NaOH. The molecular weight is measured relative to a polystyrene sulfonate standard. A UV detector with a wavelength of 280 nm is used. In this specification, "average molecular weight" should be understood as weight-average molecular weight unless otherwise specified.

[0030] In one embodiment, the lignin composition contains 3 to 12% by weight, or 4 to 9% by weight, of carbohydrates relative to the total dry matter content of the lignin composition. Therefore, it is suggested that the wood-derived lignin composition has a considerably low carbohydrate content, and that a high purity can be obtained compared to the manufactured wood-derived lignin composition.

[0031] The amount of the aforementioned carbohydrates can be determined according to the SCAN-CM 71:09 standard.

[0032] In one embodiment, the lignin composition contains 0.2 to 1.0% by weight or 0.4 to 0.8% by weight of nitrogen based on the total dry matter content of the lignin composition. The amount of nitrogen in the wood-derived lignin composition can serve as an indicator of protein traces. The amount of nitrogen present in the lignin composition can be measured using any suitable method known to those skilled in the art, such as the Kjeldahl method or catalytic pyrolysis / chemiluminescence method.

[0033] In one embodiment, the lignin composition contains 2.5 to 3.1 mmol / g or 2.6 to 3.0 mmol / g of phenolic hydroxyl groups.

[0034] In one embodiment, the lignin composition contains 2.3 to 3.2 mmol / g or 2.4 to 3.0 mmol / g of aliphatic hydroxyl groups.

[0035] Phenolic hydroxyl groups and aliphatic hydroxyl groups are 31 The lignin composition can be analyzed by 1P NMR. Preparation of the sample for NMR analysis involves first dissolving the lignin composition in a dilute NaOH solution at pH 13.0 and 65°C, and then precipitating the lignin solubilized with sulfuric acid at pH 3.0. The resulting solid material is thoroughly washed with water. For NMR analysis, each lignin composition sample is accurately weighed (25 mg), placed in a 4 ml vial, and dissolved in N,N-dimethylformamide (150 μl). After complete dissolution, pyridine (100 μl), internal standard solution (ISTD) (200 μl), endo-N-hydroxy-5-norbornene-2,3-dicarboimide (e-HNDI, 0.005 mmol), and Cr(acac)3 solution (50 μl) (11.4 mg / l) in pyridine / CDCl3 (1.6 / 1, v / v) are added. Next, add 2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphosphorane [PR(II)] from the phophytylation reagent (150 μl). Finally, add CDCI3 (300 μl) to the solution to obtain a clear dark brown solution. Immediately after preparing a freshly prepared sample at room temperature. 31Measurements are performed using 1P NMR. A Bruker 500 MHz NMR spectrometer is used for the measurement. The chemical shift is reported as a sharp signal (132.2 ppm) originating from the reaction between water and PRII.

[0036] In one embodiment, the lignin composition contains 200 to 1000 ppm or 300 to 700 ppm of sulfur. The amount of sulfur can be determined in accordance with the standard SFS-EN ISO 11885 (2009) using microwave decomposition and ICP-OES method.

[0037] In one embodiment, the weight ratio of oxygen to carbon is 0.5 to 0.8, or 0.5 to 0.7, or 0.5 to 0.6.

[0038] A method for producing a wood-derived lignin composition disclosed herein includes a step of preparing a fraction containing solid cellulose particles, wherein the total dry matter weight of the fraction containing the solid cellulose particles is 8 to 20% by weight, and the fraction containing the solid cellulose particles contains up to 3% by weight of wood shaves larger than 1 mm in size. The step of preparing such a fraction includes the following:

[0039] The fraction containing the solid cellulose particles may be supplied, for example, from a wood-based raw material including wood chips, and may be pre-treated to form a liquid fraction and a fraction containing solid cellulose particles. In this specification, "pre-treatment" should be understood as a process of converting the wood-based raw material into a fraction containing solid cellulose particles unless otherwise specified. As a result of the pre-treatment, a liquid fraction may be formed in addition to the fraction containing solid cellulose particles. The liquid fraction may be separated from the fraction containing solid cellulose particles. The fraction containing solid cellulose particles may contain a further amount of lignocellulose particles in addition to lignin. Lignocellulose contains lignin chemically bonded to cellulose particles.

[0040] The wood-based raw material can be selected from the group consisting of hardwood, softwood, and combinations thereof. The wood-based raw material may be derived from, for example, pine, poplar, beech, aspen, spruce, eucalyptus, ash, birch, etc. The wood-based raw material may be any combination or mixture thereof. The wood-based raw material may be broadleaf tree. The wood-based raw material is preferably broadleaf tree because it has a relatively high inherent sugar content, but this does not preclude the use of other types of wood. The broadleaf tree may be selected from the group consisting of beech, birch, ash, oak, maple, chestnut, willow, poplar, and mixtures thereof.

[0041] Generally, wood and wood-based raw materials are substantially composed of cellulose, hemicellulose, lignin, and extracts. Cellulose is a polysaccharide consisting of chains of glucose units. Hemicellulose includes polysaccharides such as xylan, mannan, and glucan.

[0042] In one embodiment, the wood-derived lignin composition is a lignin composition derived from hardwoods. In this way, the wood-derived lignin composition can be produced from wood such as hardwoods, hardwoods, and softwoods.

[0043] The process of preparing the wood-based raw material may include a step of forming the wood-based raw material by performing a mechanical treatment on the wood-based raw material, selected from debarking, chipping, splitting, cutting, beating, grinding, crushing, dividing, sorting, and / or washing.

[0044] Thus, the process of preparing wood-based raw materials derived from wood-based raw materials may include a step of mechanically processing the wood-based raw materials to form the wood-based raw materials. The mechanical processing may include debarking, chipping, splitting, cutting, beating, grinding, crushing, dividing, sorting, and / or washing of the wood-based raw materials. During the mechanical processing, for example, logs can be debarked and / or wood chips of a predetermined size and structure can be formed. The formed wood chips can be washed, for example, with water to remove sand, grit, stones, etc. The structure of the wood chips may also be loosened before the pre-treatment step. The wood-based raw materials may include a certain amount of bark from logs.

[0045] The process of preparing the wood-based raw materials may include the process of purchasing the wood-based raw materials. The purchased wood-based raw materials may include purchased wood chips or sawdust derived from wood-based raw materials.

[0046] The pretreatment of the wood-based raw material may include different pretreatment steps. Different pretreatment steps will alter the wood-based raw material. The purpose of the pretreatment is to form a fraction containing solid cellulose particles for further processing.

[0047] The pretreatment i) may include pre-steaming the wood-based raw material. The pretreatment may include pre-steaming the wood-based raw material obtained by the mechanical treatment. The pretreatment may include impregnation treatment and steam explosion treatment, and may include impregnation treatment and steam explosion treatment of the wood-based raw material, followed by pre-steaming of the wood-based raw material. In one embodiment, the pretreatment in step i) includes pre-steaming the wood-based raw material before the impregnation treatment to form a pre-steamed wood-based raw material. The pre-steaming of the wood-based raw material can be carried out with steam at atmospheric pressure and a temperature of 100 to 130°C. During the pre-steaming, the wood-based raw material is treated with low-pressure steam. The pre-steaming can also be carried out with steam at a temperature of 100°C or lower, or 98°C or lower, or 95°C or lower. The pre-steaming has the added benefit of reducing or removing air from inside the wood-based raw material. The aforementioned pre-steaming can be carried out in at least one pre-steaming reactor.

[0048] Furthermore, the pretreatment may include a step of impregnating the wood-based raw material with an impregnation solution at least once. The impregnation treatment can be performed on the wood-based raw material obtained by mechanical treatment and / or pre-boiling. The impregnation solution may be selected from water, at least one acid, at least one alkali, at least one alcohol, or a mixture thereof. In one embodiment, the pretreatment in step i) includes performing an impregnation treatment on the wood-based raw material at least once to form an impregnated wood-based raw material.

[0049] The wood-based raw material may be subjected to mechanical treatment and / or pre-steaming before being fed into an impregnation process. The feeder may be a screw feeder such as a plug screw feeder. The feeder may compress the wood-based raw material during the transition. Subsequently, when the wood-based raw material enters the impregnation process, it may expand and absorb the impregnation liquid.

[0050] The impregnation solution may contain water, at least one acid, at least one alkali, at least one alcohol, or a mixture thereof. The at least one acid may be selected from the group consisting of inorganic acids such as sulfuric acid (H2SO4), nitric acid, and phosphoric acid, organic acids such as acetic acid, lactic acid, formic acid, and carbonic acid, and any combination or mixture thereof. In one embodiment, the impregnation solution contains sulfuric acid, for example, dilute sulfuric acid. The concentration of the acid may be 0.3-5.0% w / w, 0.5-3.0% w / w, 0.6-2.5% w / w, 0.7-1.9% w / w, or 1.0-1.6% w / w. The impregnation solution may act as a catalyst that affects the hydrolysis of hemicellulose in the wood-based raw material. In one embodiment, impregnation is carried out using only water, i.e., by auto-hydrolysis. In one embodiment, the wood-based raw material may be impregnated by alkaline hydrolysis. The alkali used in the alkaline hydrolysis may be any metal hydroxide. Examples of alkalis used in the aforementioned alkaline hydrolysis include NaOH, KOH, and Ca2(OH)3.

[0051] The impregnation treatment may be carried out in at least one impregnation reactor or container. In one embodiment, two or more impregnation reactors are used. Transfer from one impregnation reactor to another may be performed by a screw feeder.

[0052] The impregnation treatment may be carried out by transporting the wood-based material through at least one impregnation reactor that is at least partially filled with the impregnation liquid, that is, the wood-based material may be transported into the impregnation reactor, submerged in the impregnation liquid, and then transported out of the impregnation reactor so that the wood-based material is homogeneously impregnated in the impregnation liquid. As a result of the impregnation treatment, an impregnated wood-based material is formed. The impregnation treatment may be carried out in a batch or in a continuous manner.

[0053] The residence time of the wood-based raw material in the impregnation reactor, that is, the time the wood-based raw material is in contact with the impregnation liquid, may be 5 seconds to 5 minutes, 0.5 to 3 minutes, or about 1 minute. The temperature of the impregnation liquid may be, for example, 20 to 99°C, 40 to 95°C, or 60 to 93°C. Lowering the temperature of the impregnation liquid to 100°C or below provides the added benefit of preventing or reducing the dissolution of hemicellulose.

[0054] After the impregnation treatment, the impregnated wood-based raw material can be left in a storage tank or silo for a predetermined time to stabilize the impregnation liquid absorbed by the wood-based raw material. This predetermined time may be 15 to 60 minutes, or for example, about 30 minutes.

[0055] In one embodiment, the wood-based raw material is impregnated with dilute sulfuric acid at a concentration of 1.32% w / w and a temperature of 92°C.

[0056] The pretreatment may include a step of performing a steam explosion treatment on the wood-based raw material. The steam explosion treatment may also be performed on the wood-based raw material after the impregnation treatment. That is, the pretreatment may include a step of performing a steam explosion treatment on the impregnated wood-based raw material to form a steam-treated wood-based raw material.

[0057] In one embodiment, the pretreatment includes mechanical treatment of a wood-based material to form a wood-based raw material, pre-steaming of the wood-based raw material to form a pre-steamed wood-based raw material, impregnation treatment of the pre-steamed wood-based raw material to form an impregnated wood-based raw material, and steam-explosion treatment of the impregnated wood-based raw material. In one embodiment, the pretreatment includes pre-steaming of the wood-based raw material, impregnation treatment of the pre-steamed wood-based raw material, and steam-explosion treatment of the impregnated wood-based raw material. In one embodiment, the pretreatment includes impregnation treatment of the wood-based raw material and steam-explosion treatment of the impregnated wood-based raw material. That is, the wood-based raw material after the impregnation treatment may be subjected to steam-explosion treatment thereafter. Alternatively, the wood-based raw material after pre-steaming may be subjected to impregnation treatment, and then the wood-based raw material after the impregnation treatment may be subjected to steam-explosion treatment.

[0058] The wood-based raw material can be stored, for example, in a chip bin or silo between different processing steps. Alternatively, the wood-based raw material may be continuously transported from one processing step to the other.

[0059] In one embodiment, the pretreatment in step i) includes steaming and exploding the impregnated wood-based material to form a steamed wood-based material. The pretreatment may include steaming and exploding the impregnated wood-based material, which is performed by treating the impregnated wood-based material with steam at a temperature of 130 to 240°C, 180 to 200°C, or 185 to 195°C under a pressure of 0.17 to 3.25 MPaG, followed by rapidly and explosively depressurizing the wood-based material. The impregnated wood-based material may be treated with steam for 1 to 20 minutes, or 1 to 20 minutes, or 2 to 15 minutes, or 4 to 13 minutes, or 3 to 10 minutes, or 3 to 8 minutes before the steamed wood-based material is rapidly and explosively depressurized.

[0060] In this specification, "steam explosion treatment" may refer to a semi-hydrolysis process in which the raw material is treated in a reactor (steam explosion reactor) with steam at a temperature of 130-240°C, 180-200°C, or 185-195°C under a pressure of 0.17-3.25 MPaG, and then a rapid and explosive depressurization is performed to break the fibrous structure of the raw material.

[0061] The steaming and explosion treatment may be carried out in a pressurized reactor. The steaming and explosion treatment in the pressurized reactor may be carried out by treating the impregnated wood-based raw material with steam at a temperature of 130 to 240°C, 180 to 200°C, or 185 to 195°C under a pressure of 0.17 to 3.25 MPaG, followed by a rapid and explosive depressurization of the raw material. The impregnated wood-based raw material may be introduced into the pressurized reactor using a compression conveyor such as a screw feeder. If used during transport by the screw feeder, the liquid acid is removed, a portion of the impregnation liquid absorbed by the wood-based raw material is removed as a presert, and the majority remains in the raw material. The impregnated wood-based raw material may be introduced into the pressurized reactor together with steam and / or gas. The pressure of the pressurized reactor can be controlled by adding steam. The pressurized reactor may be operated continuously or in batch mode. The impregnated wood-based raw material, for example, the wood-based raw material after impregnation treatment, may be introduced into the pressurized reactor at a temperature of 25 to 140°C. The residence time of the raw material in the pressurized reactor can be 0.5 to 120 minutes. In this specification, "residence time" means the time from when the raw material is introduced into or enters the pressurized reactor, etc., until the raw material is discharged or ejected, unless otherwise specified.

[0062] The impregnated raw material placed in the pressurized reactor may be immersed in an impregnation solution such as sulfuric acid. In one embodiment, the amount of sulfuric acid in the steam explosion treatment may be 0.10 to 0.75% by weight relative to the total dry matter amount of the wood-based raw material. The amount of acid present in the steam explosion treatment can be determined by measuring the sulfur content of the liquid of the wood-based raw material after steaming or the liquid portion of the wood-based raw material after steaming. The amount of sulfuric acid in the steam explosion reactor can be determined by subtracting the amount of sulfur in the wood-based raw material from the measured amount of total sulfur in the steamed wood-based raw material.

[0063] As a result of the partial hydrolysis of the wood-based raw material affected by the steam explosion treatment in the reactor, the hemicellulose present in the wood-based raw material may be hydrolyzed or decomposed into, for example, xylose oligomers and / or monomers. Hemicellulose contains polysaccharides such as xylan, mannan, and glucan. This causes xylan to be hydrolyzed into xylose, a monosaccharide. In one embodiment, the conversion rate of xylan present in the wood-based raw material to xylose by partial hydrolysis is 87-95%, 83-93%, or 90-92%.

[0064] Therefore, by steaming and exploding the raw material, a steamed wood-based raw material may be formed. The steamed wood-based raw material after steaming and exploding may be subjected to steam separation. The steamed wood-based raw material after steaming and exploding may be mixed with or combined with a liquid such as water. The steamed wood-based raw material after steaming and exploding may be mixed with a liquid to form a slurry. The liquid may be pure water or water containing C5 sugar. The water containing C5 sugar may be reclaimed water after separating and / or washing the fraction containing the solid cellulose particles before enzymatic hydrolysis. The steamed wood-based raw material may be mixed with a liquid, and the resulting mass may be mechanically homogenized to decompose the aggregates. The slurry may contain a liquid phase and a solid phase. The slurry may contain solid cellulose particles.

[0065] In one embodiment, the pretreatment in step i) includes mixing the steamed wood-based raw material with a liquid to form a slurry.

[0066] The liquid fraction and the fraction containing solid cellulose particles can be separated from the slurry, for example, by a solid-liquid separation step. The solid-liquid separation step may include a washing step. The washing can be carried out until the amount of soluble organic components in the fraction containing solid cellulose particles is 0.5 to 5% by weight, or 1 to 4% by weight, or 1.5 to 3% by weight, relative to the total dry matter.

[0067] The solid-liquid separation step can be carried out by displacement washing or countercurrent washing.

[0068] Displacement washing, or exchange washing, is a method of separating solids from liquids using a small amount of washing solution. Thus, displacement washing can be considered an operation that allows for the washing of solid particles with a minimal amount of washing solution, such as water.

[0069] In backwashing, the fraction containing the solid cellulose particles typically moves in the forward direction, while the washing solution, such as water, flows in the reverse direction. For displacement washing, the consumption of the washing solution can be significantly reduced even with backwashing.

[0070] Backwashing may include at least two solid-liquid separation steps and one dilution with a washing solution in between. The washing solution may be clean water. The amount of water required depends on the total number of solid-liquid separation steps, the total amount of dry matter in the feed for the solid-liquid separation steps, and the total amount of dry matter in the fraction containing the solid cellulose particles after each solid-liquid separation step.

[0071] The cleaning solution may be fresh cleaning water or recycled cleaning water. The cleaning water may be fresh water, drinking water, or a sugar-containing solution with low sugar content. The conductivity of the cleaning solution can be about 0.1 mS / cm.

[0072] The ratio of the cleaning solution to the solid content may be 0.5:1 to 8:1 (w / w), or 0.5:1 to 5:1 (w / w), or 0.5:1 to 3:1 (w / w), or 0.5:1 to 2:1 (w / w) in the case of displacement cleaning.

[0073] By measuring the conductivity of the liquid fraction recovered through this process, the progress of displacement washing and backwashing can be monitored. When the conductivity of the liquid fraction is below a predetermined threshold of 0.35 mS / cm, it can be determined that the desired amount of C5 sugar and other soluble impurities has been removed, and washing may be terminated. In one embodiment, washing is continued until the conductivity of the liquid fraction becomes 0.1 to 1.0 mS / cm or 0.2 to 0.5 mS / cm.

[0074] As a result of washing, a fraction is formed containing solid cellulose particles with a total dry matter content of 15-50% by weight. In one embodiment, a fraction is formed containing solid cellulose particles with a total dry matter content of 15-50% by weight, or 21-40% by weight, or 25-40% by weight, or 30-40% by weight, or 35-40% by weight.

[0075] The fraction containing the separated solid cellulose particles may be diluted to a total dry matter content of 8-20% by weight, 10-18% by weight, or 15-16% by weight. Therefore, if necessary, the fraction containing the separated solid cellulose particles may be diluted in step i). The need for dilution depends on the total dry matter content that the fraction containing the solid cellulose particles may have as a result of the separation step. That is, if the total dry matter content of the fraction containing the solid cellulose particles exceeds 20% by weight as a result of the separation step, the fraction containing the solid cellulose particles may be diluted. If the total dry matter content of the fraction containing the solid cellulose particles is 8-20% by weight as a result of the separation step, dilution is not necessary. The fraction containing the solid cellulose particles may be diluted with water and / or other liquids containing at least soluble carbohydrates.

[0076] In one embodiment, in step i), the fraction containing the solid cellulose particles may be diluted with water so that the total dry matter content is 8-20% by weight, 10-18% by weight, or 15-16% by weight.

[0077] The liquid fraction may contain sugars from hydrolyzed hemicellulose and by-products such as soluble lignin. In one embodiment, the liquid fraction contains carbohydrates such as C5 sugars (C5H 10 O5 or C5(H2O) n ). The liquid fraction may contain monosaccharides (C6H 12 O6 or C5H 10 O5), disaccharides (C 12 H 22 O 11 ), oligosaccharides and / or polysaccharides ((C6H 10 O5) n or (C5H8O4) n ) and other carbohydrates. In one embodiment, the liquid fraction contains soluble C5 carbohydrates (C5H 10 O5 or C5(H2O) n ) and other carbohydrates. The liquid fraction may contain other components.

[0078] The fraction containing the solid cellulose particles may contain lignin in addition to cellulose. In one embodiment, the fraction containing the solid cellulose particles contains carbohydrates, such as solid C6 carbohydrates (C6H 12 O6 or C6(H2O) n ) and lignin. The fraction containing the solid cellulose particles may contain other carbohydrates and other components.

[0079] In one embodiment, the step of pretreating the woody raw material is a step of pre-steaming the woody raw material with steam at a temperature of 100 to 130 °C under atmospheric pressure; a step of impregnating the pre-steamed raw material with an impregnating solution containing sulfuric acid at a concentration of 0.3 to 5.0% w / w, or 0.5 to 3.0% w / w, or 0.6 to 2.5% w / w, or 0.7 to 1.9% w / w, or 1.0 to 1.6% w / w and at a temperature of 20 to 99 °C, or 40 to 95 °C, or 60 to 93 °C; a step of subjecting the impregnated woody raw material to steam at a temperature of 130 to 240 °C, or 180 to 200 °C, or 185 to 195 °C, and then performing a cooking explosion treatment of rapidly and explosively reducing the pressure; The process involves mixing the steamed wood-based raw material with a liquid to form a slurry, The process includes separating the slurry into a liquid fraction and a fraction containing solid cellulose particles.

[0080] In this way, a fraction containing solid cellulose particles with a size larger than 1 mm as measured by the Somerville method is obtained, containing up to 3% by weight of wood shaves. In one embodiment, the total dry matter content of the fraction containing the solid cellulose particles is 8-20% by weight, or 10-18% by weight, or 15-16% by weight. Surprisingly, the inventors found that having a total dry matter content of 8-20% by weight of the fraction containing the solid cellulose particles when performing the enzymatic hydrolysis step ii) adds the benefit of improved conversion efficiency. Enzymatic hydrolysis If the total dry matter content in the fraction subjected to decomposition is too high, mixing in the enzymatic hydrolysis reactor may be poor, resulting in a low conversion rate of cellulose to carbohydrates. This may increase the amount of unwanted carbohydrates in the lignin. The specified total dry matter content is used in the enzymatic hydrolysis steps, namely the first enzymatic hydrolysis step and the second enzymatic hydrolysis step, and, if necessary, the pre-hydrolysis step. (Preliminary hydrolysis step) After going through that process, it may be maintained at essentially the same level.

[0081] The pretreatment described above may affect the size of the wood shaves. Up to 3% by weight of wood shaves in the fraction containing the solid cellulose particles may be wider than 1 mm, as determined by the Somerville method, when the fraction containing the solid cellulose particles is subjected to the following enzymatic hydrolysis. A large amount of shaves may adversely affect the lignin.

[0082] Step ii) includes a step of performing enzymatic hydrolysis on the fraction containing the solid cellulose particles of step i). As is generally known, the enzymes used in enzymatic hydrolysis contain nitrogen. When the enzymatic hydrolysis step is performed on the fraction containing the solid cellulose particles of step i), the amount of nitrogen entering the enzymatic hydrolysis step can be 0.05 to 0.6% by weight relative to the total dry matter of the fraction containing the solid cellulose particles. In one embodiment, the amount of nitrogen entering the enzymatic hydrolysis step is adjusted to 0.05 to 0.6% by weight, or 0.1 to 0.5% by weight, or 0.15 to 0.4% by weight, relative to the total dry matter of the fraction containing the solid cellulose particles.

[0083] The amount of nitrogen entering the enzymatic hydrolysis step can be adjusted by adjusting the amount of enzyme used. The amount of nitrogen, and therefore the amount of enzyme used in the enzymatic hydrolysis step, can be determined according to the concentration of the selected enzyme and the enzyme composition used.

[0084] The inventors have surprisingly found that the total amount of enzyme used to produce the wood-derived lignin composition in the enzymatic hydrolysis step can be substantially reduced compared to conventionally known steps. Reducing the total amount of enzyme used not only affects the manufacturing cost and process, but also the final product produced, that is, it is possible to produce a high-purity wood-based lignin composition.

[0085] The inventors have surprisingly found that when the total dry matter content of the fraction containing solid cellulose particles is 8-20% by weight, and the fraction containing the solid cellulose particles contains up to 3% by weight of wood shaves larger than 1 mm, the total amount of enzyme required for the enzymatic hydrolysis step can be reduced. Thus, the inventors have surprisingly found that the fraction containing the solid cellulose particles has the property of efficiently converting sugars present during the enzymatic hydrolysis step even with a small amount of enzyme. Furthermore, for the quality of the manufactured lignin composition, it is important that not too much shave is included in the enzymatic hydrolysis by cellulose.

[0086] In one embodiment, the enzyme hydrolysis step ii) includes a pre-hydrolysis step before the first enzyme hydrolysis step iia), in which the fraction containing the solid cellulose particles is subjected to the pre-hydrolysis step for 1 to 2 hours while maintaining the pH at 3.5 to 6.5, or 4.0 to 6.0, or 4.5 to 5.5. The first enzyme hydrolysis step may be performed directly on the pre-hydrolyzed fraction containing the solid cellulose particles. That is, a separation and purification step is not required between the pre-hydrolysis step and the first enzyme hydrolysis step. In one embodiment, the viscosity of the fraction containing the solid cellulose particles before the pre-hydrolysis step is 2000 to 7000 mPas. In one embodiment, the viscosity of the fraction containing the solid cellulose particles decreases by at least 70%, at least 75%, or at least 80% during the pre-hydrolysis step. That is, after the pre-hydrolysis step, the viscosity of the fraction containing the solid cellulose particles decreases by at least 70%, at least 75%, or at least 80% compared to the viscosity of the fraction before the pre-hydrolysis step. The viscosity can be measured using a Brookfield viscometer (10 rpm, spindle type vane, spindle size 73) under conditions of 12% suspended solids and a temperature of 50°C.

[0087] In one embodiment, the first enzymatic hydrolysis step and / or the second enzymatic hydrolysis step can be carried out at a temperature of 30 to 70°C, 35 to 65°C, 40 to 60°C, 42 to 59°C, 45 to 58°C, or 47 to 57°C while maintaining the pH of the fraction containing the solid cellulose particles at a pH value of 3.5 to 6.5, or 4.0 to 6.0, or 4.5 to 5.5.

[0088] In one embodiment, the first enzymatic hydrolysis step is continued for 24 to 72 hours, 25 to 40 hours, or 28 to 31 hours.

[0089] In one embodiment, the second enzymatic hydrolysis step is continued for 24 to 72 hours, or 32 to 65 hours, or 35 to 50 hours, or 38 to 47 hours.

[0090] The enzyme is a catalyst for enzymatic hydrolysis. The enzymatic reaction can reduce viscosity by lowering the pH and shortening the length of the cellulose fibers. By enzymatic hydrolysis of the fraction containing the solid cellulose particles, cellulose can be converted into glucose monomers by the enzyme. The lignin present in the fraction containing the solid cellulose particles may remain substantially solid.

[0091] The aforementioned enzymatic hydrolysis can use at least one enzyme. The at least one enzyme may be selected from the group consisting of cellulase, hemicellulase, laccase, and lignolytic peroxidase. Cellulase is a polyprotein complex consisting of synergistic enzymes having different specific activities, and is divided into exo and endocellulase (glucanase) and β-glucosidase (cellobiose). The enzyme may be a commercially available cellulase mixture or may be manufactured locally.

[0092] If a preliminary hydrolysis step is used, the enzyme required for the enzymatic hydrolysis step in step ii) may be added only in the preliminary hydrolysis step.

[0093] Cellulose is an insoluble linear polymer in which glucose units are linked by β-1-4-glucosidic bonds. During the enzymatic hydrolysis described above, the cellulose chain is cleaved by breaking at least one β-1-4-glucosidic bond.

[0094] In one embodiment, the solid fraction containing the lignin from the enzymatic hydrolysis step of step ii) is subjected to at least one, at least two, or at least three purification steps. Each of the at least one purification steps may include restrush the solid fraction containing the lignin, and then perform a solid-liquid separation step on the formed slurry. The solid fraction containing the lignin may be restrush with a diluent such as water. A solid-liquid separation step may be performed on the restrush lignin fraction. The diluent from the solid-liquid separation may be recycled to the preliminary hydrolysis step and / or to step iic) which restrushes the solid fraction containing the lignin separated from step iib).

[0095] The solid-liquid separation described herein, such as the first solid-liquid separation step and the second solid-liquid separation step, can be carried out by backwashing, displacement washing, filtration, decantation, and / or centrifugation. Examples of filtration include vacuum filtration, reduced pressure filtration, overpressure filtration, and filter pressing. Decanting may also be repeated to improve separation efficiency. The solid-liquid separation can be carried out using a decanter centrifuge. In one embodiment, the first solid-liquid separation step and / or the second solid-liquid separation step are carried out by filtration, decantation, and / or centrifugation.

[0096] Furthermore, the solid fraction containing the lignin separated in step iib) minutes The mixture may be re-slurried with a liquid in step iic). The liquid may be, for example, water. The liquid may also be a reused diluent from the purification process.

[0097] The method disclosed herein adds the utility of providing a wood-derived lignin composition with a high lignin content. Furthermore, the wood-derived lignin composition is provided with the utility of satisfying the purity characteristics necessary for use in composites, fillers, and the like. [Examples]

[0098] The embodiments of this disclosure are described in detail below, and examples are shown in the accompanying drawings.

[0099] The following description discloses embodiments in enough detail that a person skilled in the art could utilize the methods based on this disclosure. Not all steps of the embodiments are described in detail, as some steps may be obvious to a person skilled in the art based on this disclosure.

[0100] For simplicity, when repeating components, the item numbers are maintained in the following exemplary embodiments.

[0101] Figure 1, attached, shows in some detail one embodiment of a flowchart for a method of producing a wood-derived lignin composition. The method for producing a wood-derived lignin composition in Figure 1 includes a step of preparing a fraction containing solid cellulose particles, wherein the total dry matter weight of the fraction containing the solid cellulose particles is 8 to 20% by weight, and the fraction containing the solid cellulose particles contains up to 3% by weight of wood shaves larger than 1 mm in size as determined by the Somerville method.

[0102] The fraction containing the solid cellulose particles may be provided, for example, from a wood-based raw material that includes wood chips and has been pre-treated to form a liquid fraction and a fraction containing solid cellulose particles (step i in Figure 1). The liquid fraction and the fraction containing solid cellulose particles can be separated, for example, by a solid-liquid separation step.

[0103] Next, the fraction containing the obtained solid cellulose particles is subjected to a first enzymatic hydrolysis step for 8 to 72 hours to produce a first hydrolysis product (step iia in Figure 1). Then, the first hydrolysis product is subjected to a solid fraction containing lignin. minutes and The lignin is then separated into a liquid carbohydrate fraction (i.b). Next, the solid fraction containing the separated lignin is separated. minutes The lignin is then re-slurried (step iic in Figure 1). Next, the solid fraction containing the re-slurried lignin is prepared. minutesIn contrast, the second enzymatic hydrolysis step of step iid) is carried out for 8 to 72 hours to form a second hydrolysis product, which is then separated into a liquid carbohydrate fraction and a solid component containing lignin by, for example, a second solid-liquid separation step (step iid) in Figure 1). Next, the solid fraction containing the lignin from the enzymatic hydrolysis step of step ii) is... minutes In contrast, a purification process is performed at least once to obtain the lignin composition (step iii in Figure 1).

[0104] [Example 1 - Production of wood-derived lignin composition] In this example, a lignin composition derived from wood was prepared.

[0105] First, a wood-based raw material containing beech chips was prepared. Next, the wood-based raw material was pre-treated as follows.

[0106] The wood-based raw material was pre-steamed. The pre-steaming of the wood-based raw material was carried out at atmospheric pressure with steam at a temperature of 100°C for 180 minutes. Next, the pre-steamed raw material was impregnated with dilute sulfuric acid at a concentration of 1.32 w / w and a temperature of 92°C. The pre-steamed wood-based raw material was exposed to the impregnation solution for 30 minutes. After that, the impregnated wood-based raw material was subjected to a steam explosion treatment. The steam explosion treatment was carried out by treating the impregnated wood-based raw material with steam at a temperature of 191°C under atmospheric pressure, followed by a rapid, explosive depressurization. The amount of sulfuric acid in the steam explosion reactor was 0.33% by weight relative to the total dry matter amount of the wood-based raw material. In the measurement of the amount of sulfuric acid, the sulfur content of the wood was 0.02% by weight relative to the total dry matter amount of the wood used.

[0107] In the aforementioned pretreatment, the conversion rate of xylan to xylose in the wood-based raw material was 91%, and the ratio of solubilized glucose to solubilized xylose measured by HPLC-RI was approximately 0.15. Next, the steamed wood-based raw material was mixed with water in a mixing container to form a slurry.

[0108] Subsequently, a solid-liquid separation process separated the slurry into a liquid fraction and a fraction containing solid cellulose particles, and in this embodiment, backwashing was performed. The fraction containing solid cellulose particles also contained lignin.

[0109] The total dry matter content of the fraction containing the solid cellulose particles was 30% by weight. Furthermore, it was confirmed that up to 3% by weight of the wood shaves in the fraction containing the solid cellulose particles was wider than 1 mm as measured by the Somerville method.

[0110] Next, the fraction containing the solid cellulose particles was diluted with water to a total dry matter content of approximately 13% by weight, and the first enzymatic hydrolysis step was carried out in a batch reactor under the following conditions. Initial pH = 5.0 adjusted with NaOH. Enzymes = commercially available cellulase mixtures, Amount of nitrogen entering the enzyme reactor = 0.375% Amount of enzyme solution added = 6.5% by weight based on total dry matter. Duration of stay = 40 hours, Temperature during the process: 47-52°C.

[0111] The first hydrolysis step produced a first hydrolysis product. Next, the first hydrolysis product was separated using a decanter centrifuge in a first solid-liquid separation step, which separated the solid fraction containing lignin. minutes and The liquid carbohydrate fraction was separated from the other fraction.

[0112] Next, the solid fraction containing the separated lignin was mixed with water to re-slurry it so that the total dry matter content was 13% by weight.

[0113] Next, the solid fraction containing the re-slurried lignin was subjected to a second hydrolysis step in a batch reactor without adding enzymes under the following conditions. Initial pH = 5.0 adjusted with NaOH. Residence time = 60 hours, Temperature during the process: 47-52°C.

[0114] The second hydrolysis step produced a second hydrolysis product. Next, the second hydrolysis product was separated into a solid fraction containing lignin and a liquid carbohydrate fraction by a second solid-liquid separation step, i.e., a two-stage separation using a decanter centrifuge. As a final step, the separation further included a filter press.

[0115] Next, the solid fraction containing the lignin was subjected to a purification process including backwashing with water as the washing solution to obtain the lignin composition.

[0116] Next, the wood-derived lignin composition was analyzed by the TAPPI 222 method, and the carbohydrates were analyzed by HPLC-RI using a Waters e2695 Alliance separation module, a Waters 2998 photodiode array, and a Waters 2414 refractive index detector. Separation was performed using a 300 mm × 7.8 mm Bio-Rad Aminex HPX-87 column equipped with a Microguard de-ashing and a Carbo-Pguard column in series. Ultrapure water was used as the eluent. The results are shown in the table below.

[0117] [Table 1]

[0118] Those skilled in the art will see that, with advances in technology, the basic concepts may be implemented in various ways. Therefore, the embodiments are not limited to the examples described above, and instead, they may be modified within the scope of the claims.

[0119] The embodiments described herein may be used in any combination. Several embodiments may be combined to form further embodiments. The wood-derived lignin compositions or methods disclosed herein may include at least one of the embodiments described above. It should be understood that the above effects and benefits may relate to one embodiment or to several embodiments. The embodiments are not limited to solving any or all of the described problems or having any or all of the described effects and benefits. Furthermore, it should be understood that references to items marked "one" refer to one or more of those items. In this specification, "includes" is used to mean including subsequent features or effects without excluding the presence of one or more additional features or effects.

Claims

1. A lignin composition derived from hardwood, Based on the total dry matter amount of the lignin composition, 80 to 90% by weight of acid-insoluble lignin having an average molecular weight of 5000 to 15000 Da, Carbohydrates make up 1.5-15% by weight, Soluble components 0.5 to 6% by weight, It contains 0.2 to 1.5% by weight of nitrogen. A lignin composition derived from hardwood, having a carbon-to-oxygen weight ratio of 0.5 to 0.

8.

2. The hardwood-derived lignin composition according to claim 1, comprising 82-90% by weight, or 84-90% by weight, or 87-90% by weight, or 88-90% by weight, of the total dry matter content of the lignin composition.

3. The hardwood-derived lignin composition according to claim 1 or 2, wherein the average molecular weight of the acid-insoluble lignin is 5,500 to 12,000 Da or 6,000 to 10,000 Da.

4. A lignin composition derived from hardwood according to any one of claims 1 to 3, comprising 3 to 12% by weight or 4 to 9% by weight of carbohydrates based on the total dry matter content of the lignin composition.

5. A lignin composition derived from hardwood according to any one of claims 1 to 4, comprising 0.2 to 1.0% by weight or 0.4 to 0.8% by weight of nitrogen based on the total dry matter content of the lignin composition.

6. A lignin composition derived from hardwood according to any one of claims 1 to 5, containing phenolic hydroxyl groups in an amount of 2.5 to 3.1 mmol / g or 2.6 to 3.0 mmol / g.

7. A lignin composition derived from hardwood according to any one of claims 1 to 6, containing aliphatic hydroxyl groups in an amount of 2.3 to 3.2 mmol / g or 2.4 to 3.0 mmol / g.

8. A lignin composition derived from hardwood according to any one of claims 1 to 7, wherein the weight ratio of oxygen to carbon is 0.5 to 0.7, or 0.5 to 0.

6.

9. A lignin composition derived from hardwood according to any one of claims 1 to 8, containing sulfur in an amount of 200 to 1000 ppm or 300 to 700 ppm.

10. A method for producing a lignin composition derived from hardwood, comprising the following steps i), ii) and iii). Note Step i) A step of preparing a wood-based raw material containing wood chips derived from wood-based raw materials, wherein the wood-based raw material is hardwood, and the wood-based raw material is pretreated to form a fraction containing solid cellulose particles. Here, the pretreatment includes impregnating the wood-based raw material at least once to form an impregnated wood-based raw material, steaming and explosion treatment of the impregnated wood-based raw material to form a steamed wood-based raw material, mixing the steamed wood-based raw material with a liquid to form a slurry, and separating the liquid fraction from the slurry from the fraction containing the solid cellulose particles. Furthermore, the total dry matter content of the fraction containing the solid cellulose particles is 8 to 20% by weight, and up to 3% by weight of the wood shaves in the fraction containing the solid cellulose particles has a width greater than 1 mm as determined by the Somerville method. Step ii) A step of performing an enzymatic hydrolysis process on the fraction containing the solid cellulose particles from step i). Here, the amount of nitrogen sent to the enzymatic hydrolysis process along with the enzyme is adjusted to 0.05 to 0.6% by weight, based on the total dry matter content of the fraction containing the solid cellulose particles. The enzymatic hydrolysis process also includes the following steps iiia) to iiie). Step iia) A step in which a first enzymatic hydrolysis step is performed on the fraction containing the solid cellulose particles for 8 to 72 hours to produce a first hydrolysis product. Step iib) A step in which the first hydrolysis product is separated into a solid fraction containing lignin and a liquid carbohydrate fraction by a first solid-liquid separation process. Step ii) A step in which the solid fraction containing the lignin separated in step iiib) is mixed with a liquid to form a slurry again. Step iid) A step in which a second enzymatic hydrolysis step is performed on the reslurried solid fraction containing the lignin for 8 to 72 hours to produce a second hydrolysis product. Step iii) A step in which the second hydrolysis product is separated into a solid fraction containing lignin and a liquid carbohydrate fraction by a second solid-liquid separation process. Step iii) Providing the lignin composition by performing at least one purification step on the solid fraction containing the lignin from the enzymatic hydrolysis process of Step ii). Herein, the at least one purification step in Step iii) is continued until a lignin composition containing 0.5 to 6% by weight of a soluble component is provided.

11. The method according to claim 10, wherein each of the at least one purification steps involves restrifying the solid fraction containing the lignin and then performing a solid-liquid separation process on the formed slurry.

12. The method according to claim 10 or 11, wherein the pretreatment in step i) includes pre-boiling the wood-based raw material before the impregnation treatment to form a pre-boiled wood-based raw material.

13. The method according to any one of claims 10 to 12, wherein the total dry matter content of the fraction containing the solid cellulose particles is 10 to 18% by weight, or 15 to 16% by weight.

14. The method according to any one of claims 10 to 13, wherein the amount of nitrogen sent to the enzymatic hydrolysis process along with the enzyme is adjusted to 0.05 to 0.6% by weight, or 0.1 to 0.5% by weight, or 0.15 to 0.4% by weight, based on the total dry matter content of the fraction containing the solid cellulose particles.

15. The method according to any one of claims 10 to 14, providing a lignin composition containing 0.75 to 4% by weight, or 1 to 3% by weight, or 1.5 to 2% by weight of a soluble component.

16. The method according to any one of claims 10 to 15, wherein the enzymatic hydrolysis process of step ii) includes a pre-hydrolysis step prior to the first enzymatic hydrolysis step of step iiia), wherein the pre-hydrolysis step is performed on the fraction containing the solid cellulose particles for 1 to 2 hours, during which time the pH is maintained at a pH value of 3.5 to 6.5, or 4.0 to 6.0, or 4.5 to 5.

5.

17. The method according to claim 16, wherein the first enzymatic hydrolysis step is performed directly on the fraction containing the pre-hydrolyzed solid cellulose particles.

18. The method according to any one of claims 10 to 17, wherein the first enzymatic hydrolysis step and / or the second enzymatic hydrolysis step are carried out at a temperature of 30 to 70°C, 35 to 65°C, 40 to 60°C, 42 to 59°C, 45 to 58°C, or 47 to 57°C, while maintaining the pH of the fraction containing the solid cellulose particles at 3.5 to 6.5, or 4.0 to 6.0, or 4.5 to 5.

5.

19. The method according to any one of claims 10 to 18, wherein the first enzymatic hydrolysis step is continued for 24 to 72 hours, or 25 to 40 hours, or 28 to 31 hours.

20. The method according to any one of claims 10 to 19, wherein the second enzymatic hydrolysis step is continued for 24 to 72 hours, or 32 to 65 hours, or 35 to 50 hours, or 38 to 47 hours.

21. Use of a hardwood-derived lignin composition according to any one of claims 1 to 9 for the manufacture of a composite, filler, adhesive, paint or resin.

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