FI12360U1

FI12360U1 - Lignin fraction and lignin composition

Info

Publication number: FI12360U1
Application number: FIU20184202U
Authority: FI
Inventors: Mauno Miettinen
Original assignee: Upm Kymmene Corp
Priority date: 2015-05-29
Filing date: 2015-05-29
Publication date: 2019-05-15

Description

LIGININE FACTORY AND LIGININE COMPOSITION

FIELD OF THE INVENTION

The invention relates to lignin activity. In addition, the invention relates to a lignin composition.

BACKGROUND OF THE INVENTION

Various methods of forming lignin from various raw materials, such as biomass, are known in the prior art. Many biorefinery processes, e.g. hydrolysis, produce crude lignin, such as the lignin residue, after hydrolysis of the biomass. This water-insoluble lignin residue generally contains a significant percentage of non-hydrolysed lignocellulosic particles.

Furthermore, it is already known to chemically treat lignin by dissolving lignin in a solvent such as NaOH, an alcohol-water mixture or an organic acid, and precipitating lignin with e.g. sulfuric acid or water. After that, pure lignin can be obtained, but the drawbacks of the known processes are the high operating and capital costs. Removal and / or recovery of the solvent or salt formed will result in additional costs. Lignin final dewatering is generally carried out by filtration. The size of the precipitated lignin particles is generally rather small, which negatively affects the filtration rate and the dry solids content of the filter cake.

PURPOSE OF THE INVENTION

It is an object of the invention to provide a novel method for forming a lignin strand. Another object of the invention is to provide a novel method for purifying lignin. One object of the invention is to provide a purified lignin composition having improved properties.

SUMMARY OF THE INVENTION

The lignin fraction of the present invention is characterized by what is set forth in claim 1.

The lignin composition of the present invention is characterized by what is stated in the protection requirement 11.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are appended to the invention for clarification of the invention and which are part of this disclosure, describe some embodiments of the invention and are used in conjunction with the specification to assist in explaining the principles of the invention. In the drawings: Fig. 1 is a flowchart representation of a method according to an embodiment of the present invention, Fig. 2 is a flowchart representation of a method according to another embodiment of the present invention, Fig. 3a shows raw ligne prior to release, and Fig. 3b shows raw alignin after release.

DETAILED DESCRIPTION OF THE INVENTION

In a method for forming a lignin fraction (6) from crude lignin (1), and preferably for purifying crude lignin to form a pure lignin fraction, the crude lignin (1) is processed by a processing step (24), which treatment step is mediated by enzymatic treatment, treatment with ionic fluid and combinations thereof. . The method comprises treating crude lignin (1) by releasing lignin in at least one lignin release step (3) to release lignin of lignin (1) so that lignin is released to form two solid phases, ligno cellulose and free lignin particles, and separation of the lignin fraction (6) by at least one separation step (6). 5). In a preferred embodiment, the lignin fraction (6) is purified crude ligand.

An embodiment of the present method is shown in Figure 1. Another embodiment of the present method is shown in Figure 2.

The apparatus comprises at least one release reactor (3) for releasing the crude lignin (1) in at least one release step, at least one separation device (5) for separating the lignin fraction (6) in at least one separation step for feeding at least one first feeder crude lignin (1) into the release reactor (3) ) and at least one second feeder for feeding treated crude lignin (4) from the discharge reactor (3) to the separating device (5).

Preferably, the crude lignin (1) is formed from the starting material (20). In this context, the starting material (20) means any wood or plant-based raw material. The starting material may include lignin, lignocellulose, cellulose, hemicellulose, glucose, xylose, extractives, and other biomass-specific structural components as well as foreign components such as enzymes or chemicals. In one embodiment, the starting material is selected from the group consisting of a wood-based raw material, a wood biomass, lignin-containing biomass such as agricultural waste, sugar cane waste and corn waste, multi-annual wood plants, tubular plants, recycled brown cardboard, deinking pulp and combinations thereof. In this context, crude lignin (1) means any material or composition containing lignin, essentially free of lignin. In one embodiment, the crude lignin contains less than 20 wt% of free lignin. In addition, crude lignin also contains lignocellulose having glucan units. Lignocellulose, such as glucan units, and lignin are bound to each other as a heterogeneous structure, which means that the lignin is typically not evenly distributed in the material. Crude lignin comprises mainly lignin and lignocellulose, but it may also contain hemicellulose. The crude lignin may contain one or more lignin material component. Crude lignin may contain different levels of lignin and glucan. In addition, crude algal may contain enzymes, especially after enzymatic treatment. Typically, the crude lignin is in the form of a suspension which contains water, acid, e.g. formic acid, acetic acid or sulfuric acid, alcohol or other liquid, or in the form of a cake, lump or the like. In one embodiment, the crude lignin is in the form of a suspension. Preferably, the crude lignin is a lignin residue derived from hydrolysis, e.g. cellulose.

In one embodiment, especially after treatment with an enzymatic treatment and / or ionic liquid, the crude lignin (1) contains a high proportion of carbohydrates in the form of a solid lignocellulose. After enzymatic treatment and / or treatment with ionic fluid, lignin is tightly bound to lignocellulose of crude lignin. An additional processing step is then required to release the lignin. The separation of lignin particles can be facilitated by the invention. Preferably, the separation is based on solids-solid separation. At the same time, the crude lignin is purified to give a lignin material that is more suitable for use in various applications. In the invention, the lignocellulose fraction can be recycled to enzymatic treatment, such as enzymatic hydrolysis, and / or treatment with ionic liquid. An alternative option is to utilize the recovered lignocellulose fraction in an external application.

In one embodiment, the crude lignin is diluted with liquid, e.g., water. In one embodiment, WIS% (water-insoluble solids) of crude lignin is between 1 and 50%, or between 20 and 40%, in the release step. In one embodiment, WIS% (water-insoluble solids) of crude lignin is between 1 and 35%, or between 10 and 30%, or between 15 and 30%, in the separation step. Water-insoluble solids, WIS%, can be calculated as: WIS% = (weight of washed and dried material) / (wet wash sludge weight). The low consistency of the suspension facilitates mechanical separation of free lignin particles and lignocellulose particles. In one embodiment, the weight average particle size of the crude lignin is less than 1000 µm, preferably less than 500 µm.

In one embodiment, the cellulose content, i.e. the glucan content, of crude lignin (1) is from 3 to 70% by weight, preferably from 5 to 60% by weight, and more preferably from 10 to 60% by weight, analyzed as glucose.

In one embodiment, the lignocellulosic particles are in the form of fiber webs in crude lignin. In one embodiment, the lignocellulose particle has a weight average particle size of less than 1000 µm, in one embodiment less than 500 µm, and in one embodiment less than 300 µm.

Crude lignin has been processed by enzymatic treatment and / or ionic treatment (24). In one embodiment, the crude lignin is processed by enzymatic treatment and / or ionic liquid treatment after hydrolysis (21), in which hydrolysis of the crude lignin is formed from the starting material (20).

In one embodiment, the crude lignin is processed by enzymatic treatment (24). In one embodiment, the enzymatic treatment is enzymatic hydrolysis. In one embodiment, the crude lignin is formed from the starting material and processed by enzymatic hydrolysis.

In one embodiment, the crude lignin (1) is treated by removing water, washing, filtering and / or centrifuging at at least one washing and separation step (2) prior to lignin release (3). Preferably, the crude lignin (1) is washed and the soluble carbohydrates are separated prior to lignin release (3). Preferably, the soluble carbohydrates such as soluble C6 carbohydrates (14) can be separated from the crude lignin during the washing and separation step (2). In one embodiment, the apparatus comprises at least one device, e.g., a filter or centrifuge, for treating crude lignin (1) by removing water by washing, filtering and / or centrifuging at least one washing and separation step (2) prior to lignin release (3).

In one embodiment, the crude lignin (1) is treated by release in the presence of an acid. In one embodiment, the crude lignin (1) is treated by release of the acid. In one embodiment, the crude lignin (1) is released by a heat treatment such as hydrotreatment treatment in the lignin release step (3). In one embodiment, the crude lignin is released by autohydrolysis. In one embodiment, the crude lignin is released by hydrolysis of the dilute acid. In one embodiment, the crude lignin is released in two steps. In one embodiment, the second step is carried out without the acid and the second step with the acid. In one embodiment, the release reactor (3) is a cooker. In one embodiment, the release actor (3) is a glass lined cooker, e.g., a batch-operated glass-lined cooker, or a normal continuous cooking machine. In one embodiment, the release reactor (3) is a continuous tubular reactor with a short retention time and after which the pressure is released suddenly after the reactor phase. In one embodiment, the release reactor (3) is a percolation or flow-through reactor.

In one embodiment, the temperature is 130-400 ° C during lignin release (3). In one embodiment, the temperature is at least 170 ° C during lignin release (3). In one embodiment, the temperature is 170-240 ° C during lignin release (3). Upon release, free lignin is released from the crude ligand and two solid phases, lignocellulose and free lignin particles are formed. In one embodiment, when the crude lignin is treated by release, lignin release results in a steam detonation effect to facilitate the formation of free lignin particles and to reduce the particle sizes of the lignocellulosic particles. The most effective lignin release is achieved with a short retention time at high temperature, i.e., a so-called flash effect for lignin release. The optimal process conditions are set based on the properties of the crude lignin, the purified properties of the purified lignin and the lignocellulose fraction, as well as the economic and ecological values.

In one embodiment, water is added before lignin release (3). The temperature of the water can be about 20 to 100 ° C.

In one embodiment, the apparatus comprises at least two parallel release reactors (3) for releasing lignin of crude lignin (1). Preferably, the parallel reactors facilitate the continuous process. In one embodiment, the apparatus comprises at least two consecutive release reactors (3) for releasing lignin of crude lignin (1).

In one embodiment, the release treatment strength is between the hydrolysis of normal hemicellulose (C5) and cellulose (C6), i.e. the lowest possible intensity for lignin release. A typical pH-adjusted combined strength (CS) or strength index (SI) is between 1.5 and 2.5 (defined by the equation below), where t is the time in minutes and T is the temperature in degrees Celsius.

Low strength is preferred for dissolving the low cellulose percentage, since it improves the yield of C6 carbohydrate in the enzymatic process. Further advantages include the preservation of the natural reactivity of lignin and the higher selectivity of the release treatment resulting in a cleaner sugar solution.

In one embodiment, less than 70%, preferably less than 60%, more preferably less than 50%, and most preferably less than 40% glucan is soluble during lignin release (3).

Figure 3a shows an embodiment of crude lignin prior to lignin release, and Figure 3b shows an embodiment of crude lignin after lignin release. The darker circular shapes in Figure 3b are released lignin particles and the lighter colored material is lignocellulose.

In one embodiment, the cooking liquor from lignin release may be removed during or after lignin release. Soluble carbohydrates of cooking liquor can be recovered. Alternatively, the cooking liquor may be fed to the wastewater treatment plant as such or after further treatment.

In one embodiment, carbonate is added prior to lignin release. In one embodiment, carbonate is added during lignin release. In one embodiment, the carbonate is in the form of sodium carbonate, sodium bicarbonate, carbon dioxide, other suitable carbonate or derivatives thereof, or combinations thereof. The lignin particle size can be increased by the addition of carbonate. When CO2 is released during the release phase, the softened lignin particles swell inside the pores under the influence of expanding gas. Thereafter, lignin particles having a larger particle size may be more readily separated from crude lignin.

In one embodiment, the treated crude lignin (4) is cooled after lignin release (3).

In one embodiment, the treated crude lignin (4) is washed after lignin release (3).

In one embodiment, the lignin fraction (6) is separated in one or more separation steps (5) after the lignin release step (3). In one embodiment, the lignocellulose fraction (7) is separated in one or more separation steps (5). In one embodiment, the separation is performed by mechanical separation. In one embodiment, the separation method is selected from the group consisting of centrifugal force, sedimentation, elutriation, filtration, flotation, screening, and combinations thereof. In one embodiment, separation is performed by centrifugal forces. In one embodiment, separation is carried out by sedimentation. In one embodiment, separation is performed by elutriation. In one embodiment, separation is performed by filtration. In one embodiment, separation is performed by flotation. In one embodiment, separation is performed by screening. In one embodiment, each separation step is performed by the same method. Alternatively, each separation step is performed by a different method. In one embodiment, the lignin fraction (6) is separated from the treated crude lignin (4) such that the remaining crude lignin is a lignocellulose fraction (7). In one embodiment, the lignocellulose fraction (7) is separated from the treated crude lignin (4) so that the remaining crude lignin is a lignin traction (6). Preferably, the lignin fraction (6) is purified lignin.

In one embodiment, the apparatus comprises at least one separation device (5) for separating the lignin fraction (6) from the treated crude lignin (4) and preferably for cleaning the lignin fraction (6). In one embodiment, the apparatus comprises at least two separation devices (5). In one embodiment, the separation device is based on centrifugal forces, sedimentation, elutriation, filtration, flotation, screening, or combinations thereof. The separating device may be a reactor, a vessel, a container, a drum, a cyclone, a filter, a column, a cell, a pool, a thickener or the like. In one embodiment, at least one separation step for separating the lignin fraction is performed by centrifugal forces, e.g., a basket centrifuge or decanting centrifuge such as a solid centrifuge centrifuge, or by flotation, e.g., foam flotation or column flocculation.

In one embodiment, the separation of the lignin fraction (6) is carried out in one or more separation steps. In one embodiment, the separation is performed in one separation step. In one embodiment, the separation is performed in more than one separation step. In one embodiment, the separation is performed in three separation steps. In one embodiment, the separation device (5) comprises one or more separation steps. In one embodiment, the separation step comprises one or more separation devices. In one embodiment, the lignin fraction (6) is separated in the final separation step. In one embodiment, the lignin fraction (6) is separated between the two separation steps. In one embodiment, the lignin fraction (6) is separated in the first separation step. In one embodiment, the lignin fraction (6) is separated in the first separation step and then the lignin fraction is purified in subsequent separation steps. In one embodiment, the lignin fraction (6) is separated at each separation step. In one embodiment, the lignocellulose fraction (7) is separated in the first separation step. In one embodiment, the lignocellulose fraction (7) is separated in more than one separation step. In one embodiment, the lignocellulose fraction (7) is separated at each separation step. In one embodiment, at least one separated lignocellulose stream is recycled to the desired separation step.

In another embodiment, the lignin fraction (6) is further purified by screening, preferably with a vibration screen, to remove carbon and sugar degradation products.

The separation can be carried out over a wide range of temperatures, e.g. at temperatures between 0 and 100 ° C. Higher temperatures generally make the difference easier due to lower viscosity. Generally, an almost natural process temperature is used to avoid heating or cooling.

In one embodiment, the stabilizer chemical (8) is added to the treated crude lignin (4) in connection with the separation step (5). In one embodiment, the stabilizing chemical (8) is added to the treated crude lignin (4) prior to the separation step (5). In one embodiment, the stabilizing chemical (8) is added to the treated crude lignin (4) during the separation step (5). In one embodiment, the apparatus comprises at least one feeder for adding a stabilizing chemical (8) to the treated crude lignin (4).

The stabilizing chemical (8) is added to the treated crude lignin (4) in at least one step. In one embodiment, the stabilizing chemical (8) is added to the treated crude lignin (4) in one step. In one embodiment, the stabilizing chemical (8) is added to the treated crude lignin in more than one step. In one embodiment, the stabilizing chemical (8) is added to the treated crude lignin at each separation step. In one embodiment, the stabilizing chemical (8) is added to the treated crude lignin in the first separation step and / or at least one subsequent separation step. Preferably, chemical stabilization and mechanical separation are performed.

In one embodiment, a stabilized chemical is added to the treated crude lignin and the crude lignin is mixed, preferably by high shear mixing. High shear mixing is advantageous because it facilitates adsorption of the chemical on the surfaces. The stabilizing chemical is mainly adsorbed onto lignocellulose particles.

In one embodiment, the stabilizing chemical (8) is a polysaccharide as such or a modified polysaccharide. In this context, the stabilizing chemical is typically a hydrophilic chemical. In one embodiment, the stabilizing chemical is selected from the group consisting of carboxymethylcellulose (CMC), polyanionic cellulose (PAC), other cellulose derivatives, e.g. , glycogen, callus, chrysolaminarine, native hemicellulose, modified hemicellulosis, xylan, mannan, galactomannan, galactoglucomannan (GGM), arabinoxylan, glucuronoxylan and xyloglucan, fucoidis, dextran, alginate, other polysaccharide and combinations thereof. Said stabilization micelle may be in native form or in modified form. In one embodiment, the stabilizing chemical is carboxymethylcellulose (CMC). In one embodiment, the stabilizing chemical is guar gum. Preferably, the function of the stabilizing chemicals is to keep the suspended lignocellulose particles stable during the chemical interaction. In this case, the treated lignocellulose particles remain in suspension, while the free lignin particles are separated from the suspension.

In one embodiment, wash water (9) can be added, e.g., at a temperature between 20 and 70 ° C, to a separating device (5), preferably at the final separation stage, for washing the lignin fraction (6). Alternatively, the lignin fraction (6) is washed after separation (5). In one embodiment, the lignin fraction is washed by displacement washing. The purified lignin can be easily neutralized in the washing step without negatively affecting the dewatering ability. In this context, washing water means any washing liquid or washing water. Washing water can be fresh water or recycled washing water. The wash water may be physically and / or chemically purified raw water as well as pure side stream from the biorefinery process, e.g. condensate from evaporation of the sugar. The separation process does not require ultrapure water, e.g., obtainable by ion exchange, distillation, or reverse osmosis.

In one embodiment, the lignin fraction (6) is in the form of a suspension, solid, sediment, slurry, cake or the like after the separation step. The lignin fraction (6) may also contain other components or substances than lignin particles. Preferably, the lignin fraction contains free lignin. In one embodiment, the lignin fraction contains more than 80%, preferably more than 85%, more preferably more than 90%, most preferably more than 95% lignin and less than 20%, preferably less than 15%, more preferably less than 10%, most preferably less than 5% glucan. The lignin content is defined as the combination of acid-insoluble and acid-soluble lignin.

In one embodiment, the lignin fraction (6) is treated after separation by removing water from the lignin fraction in at least one dewatering step (10) which can be selected from the separation methods described above or other suitable methods. In one embodiment, the dewatering is carried out in the separation step. In one embodiment, the lignin fraction (6) is treated by removing water in at least one filtration step, e.g., by a pressure filter or vacuum filter. In one embodiment, the lignin fraction (6) is treated by removing water in at least one purification separation step. In one embodiment, the lignin fraction is treated in a purification separation step by medium purification, e.g., by hydrocyclone, sedimentation, e.g., by thickening, elutriation, aggregation, flotation, flocculation, and / or screening. In one embodiment, the lignin fraction (6) is treated by grinding.

In one embodiment, the apparatus comprises at least one filtering device, e.g., a pressure filter or vacuum filter, for filtering and purifying the lignin fraction (6). In one embodiment, the apparatus comprises at least one dewatering device for removing water from the lignin fraction (6).

The removal of water from lignin can be improved by the present invention. Removal of the lignocellulosic sap articles clearly improves the removal of water from the lignin, as evidenced by the increasing filtration rate and / or higher solids content. Higher solids content means that lignin is more suitable for subsequent applications as such and less energy for drying.

In one embodiment, at least a portion of the ligno-cellulose fraction (7) containing lignocellulosic particles is recycled back to enzymatic treatment, such as enzymatic hydrolysis, and / or treatment with an ionic liquid. In one embodiment, at least a portion of the lignocellulose fraction (7) is recycled from the separation step (5) to enzymatic treatment, such as enzymatic hydrolysis, and / or treatment with ionic fluid. In one embodiment, at least a portion of the lignocellulose fraction (7) is recycled to a step prior to the treatment step (24), preferably prior to enzymatic treatment or treatment with an ionic liquid. In one embodiment, the lignocellulose fraction (7) is recycled to a step between the hydrolysis process (21) and the processing step (24). In one embodiment, the lignocellulosic structure (7) is recycled to a slurry tank (23) arranged before the treatment step (24). Alternatively, at least a portion of the lignocellulosic fraction (7) can be recycled to a separate hydrolysis process. In one embodiment, the apparatus comprises a recycle means for circulating the lignocellulose fraction (7). In one embodiment, a feed system is used to circulate the lignocellulose fraction (7) from the separating device (5) to an enzymatic treatment, such as enzymatic hydrolysis, and / or treatment with an ionic fluid.

Preferably, in the case of the enzymatic process, the raw material, e.g. wood material, can be utilized more efficiently in the process when the lignocellulose fraction (7) is recycled to enzymatic treatment such as enzymatic hydrolysis.

When the lignocellulose fraction (7) is recycled, the conversion can be reduced by enzymatic treatment or treatment with an ionic liquid. In one embodiment, the conversion decreases by at least 10%, or at least 20% of the previous optimal conversion rate. The enzyme dose is selected such that the desired glucan conversion to glucose is achieved by enzymatic treatment. Lower conversion allows reduction of enzyme dosage. The properties of the recycled lignocellulosic structure, particularly the small particle size, the low hemicellulose content and the low lignin content, may further reduce the enzyme dosage. In one embodiment, the feed consistency may be increased in the enzymatic treatment. This compensates for the otherwise lower cell concentration and the higher volume of enzymatic treatment tanks, such as containers for enzymatic hydrolysis, when lower conversion is used. Higher feed consistency is possible due to the lower viscosity of the pre-bonded starting material and the lignocellulose mixture compared to the pre-treated starting material alone. In a conventional process, a lower conversion would result in a corresponding decrease in the C6 sugar yield, but when the recovered lignocellulose fraction is recycled to enzymatic hydrolysis, the combined C6 yield is typically higher than that of a normal conversion level.

The lignocellulose fraction (7) may also contain other components or substances than carbohydrates such as glucan. In one embodiment, the lignocellosis lotion (7) is in the form of a suspension. This suspension contains a liquid such as water. In one embodiment, the lignocellulose fraction (7) contains from 40 to 90%, preferably from 50 to 90%, more preferably from about 60 to 90% glucan and from 10 to 60%, preferably from 10 to 50%, more preferably from about 10 to 40% lignin after the separation step (5).

In one embodiment, water is removed from the lignocellulose fraction (7), e.g., by filtration, after separation (5).

In one embodiment, the lignocellulose fraction (7) is diluted to form a diluted lignocellulose fraction (13) after the separation step (5). In one embodiment, the liquid in the lignocellulose fraction displaces, partially or completely, fresh water required for dilution of the pretreated starting material prior to enzymatic hydrolysis.

According to the present invention, a lignin composition can be formed. The lignin composition contains a lignin fraction formed by the method described herein. The lignin composition may be used as a component in the preparation of a product, such as a final product, selected from the group consisting of activated carbon, carbon fiber, lignin composite, binder material, polymers, resins, phenolic component, dispersant, feed, food or a combination thereof. In one embodiment, the lignin composition is used as an adsorbent for an oil, a hydrocarbon composition or a heavy metal. In one embodiment, the lignin composition is used as a fuel for energy production.

In one embodiment, a lig nosellulose composition can be formed. The lignocellulose composition contains a lignocellulose fraction formed by the method described herein. The lignocellulose composition can be used as a component for the preparation of a product selected from the group consisting of composites, wood composites, lignin wood composites, wood plastic composites comprising composites formed of plastic, synthetic polymers, biopolymers, rubber or combinations thereof with wood, from resins , preferably as a filler in resins, wood-based materials, wood-based fillers, building materials, building boards, adhesive plates and / or other wood-based boards such as par-tile sheet, oriented large-particle board, particle board, intralumination, glue-wood, hardboard, wave-board, waferboard, fiber board, plywood , insulating material, packaging material, barrier material or foam material. In one embodiment, the lignocellulose composition is used as a fuel for energy production. In one embodiment, the lignocellulose composition is used as a raw material for the production of microcrystalline cellulose, nanocrystalline cellulose or nanofibralized cellulose. High crystallinity and small particle size support lignocellulose use in the production of microcrystalline cellulose or nanocrystalline cellulose.

In the present invention, the separation of the lignin fraction can be optimized. The method of the present invention provides a good quality lignin fraction and a lignin composition. In particular, the purity of the ligninif structure can be improved. By improving the lignin purity and increasing the dry solids content of the lignin fraction, improved properties can be obtained in the final product. In addition, the lignocellosis lotion fraction can be recovered. Thanks to the invention, the use of raw materials and enzymes can be reduced.

The invention provides a viable way of reducing conversion in enzymatic treatment, such as enzymatic hydrolysis (EH), without negatively affecting sugar yield, sugar concentration or the size of the enzymatic hydrolysis tanks. In addition, the C 6 sugar yield can be improved in the process.

The invention preferably provides improved filterability. In addition, the invention enables the heating value of the lignin composition to be increased so that the heat value without drying can be improved by at least 50 o.

The present invention provides an industrially useful, simple and advantageous way of preparing a purified lignin-based composition and a lignocellulose-based composition. The method of the present invention is simple and simple to implement as a production process. The method of the present invention is suitable for use in the manufacture of various lignin and lignocellulose based products and end products from a variety of starting materials. Preferably, the crude lignin is purified by separating the lignocellulose particles. In addition, the lignin composition can be used as energy sources.

EXAMPLES

The invention will be described in more detail in the following examples with reference to the accompanying drawings.

Example 1 In this example, the lignin fraction (6) is formed according to the process of Figure 1.

The pretreated starting material is formed from the starting material (20), such as biomass, for example by hemihydrolysis (21). The preformed precursor material (22) formed is processed in the processing step (24), which is an enzymatic treatment such as enzymatic hydrolysis, or treatment with an ionic liquid to form crude lignin (1).

The crude lignin (1) is fed to the release reactor (3), e.g., a digester based on autohydrolysis or dilute hydrolysis of the dilute acid, to process the crude lignin by release, by means of a first feeder. Water may be added to the release reactor (3). The treated crude lignin (4) is fed from the release reactor (3) by means of a second feeder to a separation device (5) for separating the lignin fraction (6). Carboxymethylcellulose (8) can be added as a stabilizing chemical to crude lignin during separation. Preferably, the separation is carried out in more than one separation step. The lignin fraction (6) from the separator (5) is recovered. Also, the lignocellulose fraction (7) is separated. The lignocellulose fraction (7) can be recycled to enzymatic treatment, such as enzymatic hydrolysis, or treatment with an ionic liquid.

Example 2 In this example, the lignin fraction (6) is formed according to the process of Figure 2.

The pretreated starting material is formed from the starting material (20), such as biomass, for example by hemihydrolysis (21). The preformed precursor material (22) formed is fed through a reflux tank (23) to a treatment step (24), which is an enzymatic treatment, such as enzymatic hydrolysis, or treatment with an ionic liquid. The pretreated starting material (22) is processed in the processing step (24) to form the crude lignin (1).

The crude lignin (1) is filtered in a filtration apparatus (2) in which soluble carbohydrates (14) can be removed. Optionally, the crude lignin may be washed with water during or after filtration, preferably using displacement washing. The crude lignin (1) is then fed to the release reactor (3), e.g., a digester, preferably based on autohydrolysis or dilute hydrolysis of the dilute acid, to treat the crude lignin by release. Preferably, the apparatus comprises an end-of-steam blasting step. Water may be added to the release reactor. During or after the release, a liquid phase containing solubilized carbohydrates (15) can be separated. Preferably, the treated crude lignin (4) is washed after lignin release. The treated crude lignin (4) is fed from the release reactor (3) by means of a second feeder to the optional washing step and further to the separating device (5) to separate the lignin fraction (6). The lignocellulosic structure (7) is also separated. The carboxymethylcellulose (8) can be added as a stabilizing chemical to the crude lignin during separation. Preferably, the separation is carried out in more than one separation step. Washing with water (9), e.g. at a temperature between 20 and 60 ° C, can be added to the separating device (5), preferably in the final separation step, to wash the lignin fraction (6). The lignin fraction (6) from the separating device (5) is fed to a second filtering unit (10) for further processing of the lignin fraction (6), e.g., by a pressure filter. The lignin fraction (6) can be filtered and purified to form the final lignin composition (11).

The lignocellulose fraction (7) is recycled to enzymatic treatment, such as enzymatic hydrolysis, or treatment with an ionic liquid. The lignocellulose fraction (7) can be diluted in dilution step (12) to form a diluted lignocellulose fraction (13). Diluted lignocellulosic fractionation (13) is fed to the slurry tank (23) and recycled to the treatment step (24).

Example 3 In this example, lignin and lignocellulose fractions were formed.

Pre-treated biomass (PTB) was subjected to enthymatic hydrolysis with a commercial enzyme using 16% TS (total solids) feed. The enzyme dose was chosen so that after 48 h of hydrolysis, 80% glucose conversion was achieved. The residual solid material, i.e. crude lignin, was separated from the C6 carbohydrates by pressure filtration. The crude lignin was exposed to dilute acid for treatment in the release step. The crude lignin was released in the digester using the following conditions: 20.9% TS, time 210 min, temperature 181 ° C and sulfuric acid dosage 6 kg / t TS PTB. After the release treatment, the slurry was cooled in the reactor. After cooling, the pH of the slurry was 3.0.

Pressure filtration and displacement washing were used to separate the water-soluble material from the solid particles. The liberated lignin particles and the remaining lignocellulose particles were sequentially separated in four steps. The first step (coarser phase) gave a lignocellulose fraction and a semi-purified lignin fraction. The following steps (cleaner steps) were used to further purify the lignin fraction. The standard procedure was to recycle lignocellulose fractions from steps 2-4 upstream of the optimum steps of the separation process. Optionally, one or more steps (purification steps) may be used to further purify the lignocellulose fraction. The treated crude lignin was resuspended to give a 7% TS feed to the coarser phase. CMC (carboxymethylcellulose) was added at 10 kg / t TS and the temperature was 55 ° C. The slurry was pumped to a GEA Westfalia UCD205 decanter centrifuge at a feed rate of 23 kg / min using a drum speed of 2800 rpm. The separated lignin (heavy) fraction was resuspended, CMC 3 kg / t TS was added and the formed slurry was processed in the first cleaner step using a decant centrifuge. The next two cleaner stages were based on sedimentation. CMC was added at 1.5 kg / t TS in the second cleaner step, and the third cleaner step was carried out without CMC.

Lignin and carbohydrates were analyzed using TAPPI methods T-222 and T-UM 250. The results are shown in Table 1.

table 1

CL1 = crude lignin prior to boiler CL2 = crude lignin after digester LC / SS1 = lignocellulose fraction after separation step L / SS4 = lignin fraction after separation step 4

During the release phase, 15% of the glucan was hydrolyzed (solubilized), i.e. 85% of the glucan is available for enzymatic hydrolysis after 100% recovery. The lignin fraction L / SS4 was significantly cleaner than the crude lignin after the digester (CL2), indicating that the crude lignin is released from the lignin at least partially during hydrolysis of the dilute acid. The mechanical separation cannot be used to clean the crude lignin before the machine. The large biomass particles present in PTB complicated the purification of lignin because larger lignocellulosic particles tend to migrate to the heavy fraction (lignin fraction). Therefore, post-release hot blasting, e.g., steam blasting, is a preferred alternative for reducing particle size in practice. Higher conditions leading to a higher degree of glucan hydrolysis would significantly affect lignin release and subsequent separation.

Enzymatic hydrolysis was performed on a laboratory scale for a mixture of PTB and recycled lignocellulose LC / SS1 at a ratio of 87:13 in solids.

based on the total amount. The reference was the same enthymatic hydrolysis using 100% PTB material. The results are shown in Table 2.

Table 2

Based on the results, the recycled lignocellulose (Glu channel) was converted to glucose as effectively as the virgin PTB.

Example 4 In this example, the effect of the recycled lignocellulose fraction was shown on the rheology of the formed slurry. The lignocellulose strain isolated from Example 3 was used in the experiment. The ratio of PTB to recycled lignocellulose was set at 70:30 based on total solids. The suspension had a viscosity of 306 mPas (Brookfield 50 rpm). As a reference, the same pretreated biomass (PTB) was resuspended in pure water to give a suspension having a total solids (TS) of 16.8% and dissolved in water.

the solids content (WIS) was 16.5%. The suspension had a viscosity of 1876 mPas (Brookfield 50 rpm). This example demonstrates that mixing lignocellulose with pre-treated biomass provides unexpected rheological properties. This mainly shows the effect of the bipolar particle size distribution, but also the changed surface properties may be important. Lower viscosity allows for higher solids content, for example, when enzymatic hydrolysis is performed at low conversion, i.e., low carbohydrate yield, which allows otherwise reduced sugar concentration and increasing tank volume compensation. Although it would not be useful to achieve a higher solids content, a lower viscosity makes the use of a less powerful mixing step easier.

The method of the present invention is applicable in various embodiments for use in the formation of lignin fractions and lignocellulose fractions from the most diverse crude ligins.

The invention is not limited to the example described above, but many variations are possible within the scope of the inventive idea defined in the protection requirements.

Claims

PROTECTIVE CLOTHING T

A lignin fraction obtainable by a method comprising the steps of: forming a lignin fraction of crude ligne processed by a treatment step selected from an enzymatic treatment, treatment with an ionic liquid and combinations thereof, and treating the crude lignin by releasing lignin in at least one lignin release step, and separating the lignin fraction in at least one separation step.

The lignin fraction of claim 1, wherein the lignin fraction contains free lignin.

A lignin fraction according to claim 1 or 2, wherein the lignin fraction is obtainable by a process wherein the lignin release is hydrothermal treatment or hydrolysis of the dilute acid.

The lignin fraction of any one of claims 1 to 3, wherein the lignin fraction is obtainable by a method further comprising treating the crude lignin prior to lignin release by removing water, washing, filtering and / or centrifuging at at least one wash and separation step.

The lignin fraction according to any one of claims 1 to 4, wherein the lignin fraction is obtainable by a method further comprising separating the lignocellulose fraction in at least one separation step.

A lignin fraction according to any one of claims 1 to 5, wherein the lignin fraction is obtainable by a method wherein the separation is carried out in more than one separation step.

The lignin fraction according to any one of claims 1 to 6, wherein the lignin fraction is obtainable by a method further comprising adding a stabilizing chemical to the treated crude lignin in the separation step.

8. The lignin fraction of claim 7, wherein the stabilizing chemical is carboxymethylcellulose (CMC) or guar gum.

The lignin fraction according to any one of claims 1 to 8, wherein the lignin fraction is obtainable by a method further comprising recycling at least a portion of the lignocellulosic fraction from the separation step to enzymatic treatment or treatment with an ionic liquid.

The lignin extract according to any one of claims 1 to 9, wherein the lignin extract contains more than 80% lignin and less than 20% glucan.

A lignin composition comprising a lignin traction according to any one of claims 1-10.

A lignin composition according to claim 11, wherein the lignin composition is a component of a product selected from the group consisting of activated carbon, carbon fiber, lignin composite, binder material, polymers, resins, phenol component, dispersant, feed, food or a combination thereof.

The lignin composition of claim 11, wherein the lignin composition is an adsorbent for oil, hydrocarbon composition or heavy metals.