JPS6033400B2 - Lignin separation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for separably converting lignin from cellulose and hemicellulose in lignocellulosic materials and to products thus produced.

As used herein, separably converting lignin from hemicellulose and cellulose in a lignocellulosic material means that this lignin can be separated from hemicellulose and cellulose, for example by organic solvent extraction.

R.W. Hess, A.
AM. Thomsen, F. Porter (at F. Por) and J. W. Anderson, 1963 King 10
U.S. Patent No. 3,212,932 “Selec” dated May 19
tiveHgdrol侭isofLignocellu
In the lignocellulosic material, the pentose and hexose are produced in separate fractions so that each can be applied as desired to the raw material feed formulation or each can be added to the pentose and hexoses can be applied separately to various other commercial applications to which they are applicable. A two-step hydrolysis method is described. This lignocellulosic material that can be used in selective hydrolysis processes such as Hess et al. is derived from cultivated plant methods and is a type of lignocell that is readily available as a waste by-product of various industries. Contains earth-based materials. These are thus oat hulls, corn stalks and bagasse.
including. However, in particular these include wood from various trees. Lignocell. The carbonaceous material does not require special treatment before its use in this Hess et al. method, but if it is not already present in a finely divided state, this state must be reduced. Thus wood is advantageously used in the form of sawdust, wood shavings, thin chip flakes, etc. In the first-stage hydrolysis of the Hess et al. method, the lignocellulosic material selectively hydrolyzes the hemicellulose component of the lignocellulose and forms a pentose as the desired product. It is heated under parenteral conditions with an aqueous liquid. Premix or introduce the gnocellulose and aqueous liquid into a suitable pressure vessel. This can be either a continuous or batch pressure reactor equipped with a device for heating the charge at a predetermined pressure to a predetermined temperature. As mentioned above, this is done by direct steam injection. In the reactor, the pressure above the bag is 10 - 700 psL, preferably 2
The temperature is increased as quickly as possible to a value of 50-60 psi, and the temperature is simultaneously increased to a level corresponding to saturated steam.

These conditions are maintained for a relatively short period of time sufficient to substantially and selectively convert the hemicellulose component of the lignocellulose to pentose sugars. In the average case this is just 0.
3 to 10 minutes, this time generally being substantially inversely proportional to the temperature applied. As the temperature rises,
The time becomes shorter, and the lower the temperature, the longer the time. As a result, if small amounts of volatile organic acids, such as acetic acid as well as stannic acid, are initially included, a first liquid product containing a substantial portion of pentose sugars is formed, along with the remaining key acids. .

A first solid residue is also formed that is substantially pentose-free and contains primarily undegraded ligenes and decomposed cellulose. The next pressure is reduced prior to separation of liquid and solid residue products.

Whereas the time required for the pressure drop with prior art techniques was very long, i.e. on the order of several hours, keeping this at a very low value is important for the success of the method described here. It is. Thus, there is a substantially instantaneous drop in pressure resulting in what is referred to herein as a "flash flowdown." When using a continuous reactor, this blowdown time is only a few seconds. When using a large bath reaction, this blowdown time is only a few minutes. This rapid reduction in pressure has several significant effects.

Firstly, it quickly stops the hydrolysis reaction. This in turn minimizes the production of hexoses from cellulose degradation. This also minimizes the production of lignin degradation products and prevents the degradation of desired sugar products. Second, this flash blowdown evaporates any water particles present.

The resulting vapor can then be beneficially used for heat exchange with the materials charged to the reactor. Third, this flash blowdown flushes out acetic acid, formic acid, or other organic volatiles formed as products of the reaction.

A built-in operation is thus provided to separate and remove impurities from the reaction products. Fourth, flash flowdown ruptures solid residue particles.

This creates porous pores in them for more efficient processing in the second hydrolysis step. In the third stage hydrolysis of the Hess et al. process, the second stage reactor conditions are more aggressive than those prevailing in the first stage reactor.

These have as their purpose the conversion of cellulose into hexoses without inducing undue degradation of lignin. Therefore the ratio of bagged liquid to solid is 1:1-5:1, preferably 1:
It is kept within a wide range of 1-3:1.

The mineral acid concentration of the liquid treatment agent is 0.3-3. is maintained at a level of % by weight. The reactor is heated indirectly or preferably by direct injection of steam until reaching a temperature corresponding to a pressure and saturated steam of 150 to 90 sj, preferably 400 to 800 psi.

The above conditions are maintained for a time which is substantially inversely proportional to the temperature, ie the higher the temperature the shorter the time and vice versa.

During this time, which ranges from 0.3 to 10 minutes, the cellulose content of the charge is substantially selectively converted to hexoses, leaving a solid residue containing primarily unhydrolyzed lignin.

As in the first step, the reaction is carried out to evaporate excess water, to flush out any organic volatiles present, and to physically modify the lignin residue for filtering and further easy handling. It is highly desirable to end it abruptly.

For these reasons, the reactor contents are subjected to flash flowdown, for example by passing them continuously through a flowdown cyclone device. This reduces the pressure to atmospheric in just a matter of seconds. Steam from the blowdown device is vented while the solid product is washed with water in a second stage extractor.

Operation of this extractor results in the separation of the hexose liquid from the cellulose containing lignin residues, which is recycled or sent to waste. The liquid is then treated with a neutralizing agent such as calcium carbonate and any suitable solvent, additional water is added if necessary, and the mixture is filtered.

While the method of Hess et al. has contributed usefully to the art, the applicant has demonstrated that the hydrolysis that separably converts pentose bran and hexoses from IJ gunins in lignocellulosic materials is useful for producing cultivated plants. We have found that this is done at the expense of the loss of useful hemicellulose material present in lignocellulosic materials. The acid action of hydrolysis, which is necessary to break down lignocellulose, progressively destroys the fermentation value of hemicellulose, and thus an undesirably large portion of hemicellulose is required for hydrolysis of lignocellulose to occur. In the meantime, it can be made indigestible for resistant animals. There is a need to provide a method that increases the accessibility of cellulose in lignocellulosic materials, yet retains most of the fermentation value of hemicellulose.

U.S. Pat.
Dj crab stibilitsu ofFeedstuffs
forR mi female ntAnimals”, and 197
No. 3817796 “EquipluentforCon” of J.W. Algeo dated June 14, 2013
Verting the Physical and
Complex Molecular Bonds
structures of NatmaI Fe
edstuffs for R mountain minant Aui
maIS t.

D-tefferent and Less Complex
Molecular Bond Str
uctmes claw ereof'' describes an apparatus and method for exposing anti-anchor animal feed to high-pressure steam in a pressure vessel and explosive release to the atmosphere through a central valve for recovery and storage of the spongy end product; The material is characterized by its ability to readily take up water and digestible juices when ingested by ruminant animals.Cellulosic feeds such as all the usual roughhages, including hay, stalks, etc. For lignocellulosic feeds such as cottonseed hulls, rice hulls, nut shells, or coffee grounds, the vapor pressure in the pressure vessel is rapidly raised by 500 to 1000 psi and the temperature is then approximately 4700 F (24yo).
to 5460F (285qo). This method can be described as a thermomechanical method for processing lignocellulosic materials. This can also be applied to other materials such as particulate feeds that are not lignocellulosic and for these materials
A temperature range for steam of F(204oo) is used. Although Algeo's method is undoubtedly a useful contribution to the art, as taught by Algeo, 47
Applicants have discovered that raising the material to a temperature range of 00F (24300) to 5460F (28SO) sharply reduces the fermentation value of hemicellulose.

As noted above, there is a need for a process for separably converting lignin from the cellulose and hemicellulose contained in IJ gnocellulosic materials of cultivated plant methods, which may lead to For the purpose of
It almost preserves the fermentation value of the hemicellulose therein and at the same time increases the accessibility of the Q-cellulose therein to enzymatic digestion. As used herein, cultivated plant species refers to delicate-stemmed or hard-stemmed organic matter in which organic matter is produced by photosynthesis.

This material is commonly referred to as biomass. Gnocellulosic materials occur naturally as three-dimensional composites in which cellulose, hemicellulose, and lignin polymers are intimately mixed in a composite structure, which is transferred from one cultivated plant species to another and over time. Vary for specific species.

IJ gunin is an amorphous three-dimensional polymer, each molecule of which is made up of hundreds of phenylpropane units linked in various ways. Possibly in combination with hemicellulose, gunin penetrates the matrix of cellulose microfibrils in the cell wall and fills primarily the intercellular spaces.
X-ray crystallography analysis suggests that this lignin is more tightly cross-linked with hemicellulose than with Q-cellulose, as the cellulose microfibrils constitute a separate crystalline phase. The dry cellulose of cultivated plants is 23,000
It has a softening or vitrification temperature of , and because of its crystalline nature, this temperature is not significantly lowered by the presence of moisture.

In contrast, hemicellulose and gunins in cultivated plants contain 12
Since these materials are amorphous, their softening temperature varies with moisture and pressure. The polymers of cultivated plants are formed in strict morphological patterns and interconnected by covalent bonds similar to "spotwelds" and the well-known and aqueous bond between lignin and hemicellulose of cultivated plants. It is these "point welds" that create the bond. In macromolecular spot-welded complexes of cultivated plants, thermal softening is dominated by the behavior of cellulose components. Even when the sorbed water lowers the transition temperature of the amorphous components, the material has a cellulose framework that is not plasticized by water molecules.
) retains its rigidity up to temperatures close to 230°C (4460F) for maximum effectiveness. The lignocellulosic complex of cultivated plants presents a barrier to enzymes or ruminant gastric microflora that attempt to break down cellulose and hemicellulose into simple sugars.

Lignocellulosic materials differ in their degree of crosslinking. In order to improve digestibility, it is necessary to break down these lignin-carbohydrate bonds chemically and/or animalically. Another object of certain embodiments of the invention is to provide a thermomechanical process for separably converting lignin from cellulose and hemicellulose in lignocellulosic materials with negligible loss of fermentation value of the hemicellulose material. .

According to one aspect of the invention {a} Packing the IJ gnocellulosic material in ground form in a pressure vessel with a closed extrusion die outlet; plasticizing the lignocellulosic material by rapidly filling the pressure vessel with at least 50 msi of steam to guide the lignocellulosic material;
As soon as the lignocellulosic material is in a plasticized state,
The extrusion die outlet is opened and the lignocellulosic material in a plasticized state is extruded from the pressure vessel instantaneously through the extrusion die outlet to the atmosphere, thereby converting said material into a separable form from cellulose and hemicellulose or into granules along with gunin. A method is provided for separably converting lignin from cellulose and hemicellulose in a lignocellulosic material comprising exiting an extrusion die in the form of a lignocellulosic material.

Preferably the lignocellulosic material is extruded onto the impact surface.

In embodiments of the invention, the lignocellulosic material is brought to a temperature within the range of 200 to 238°C within 49 stages.

In certain embodiments of the invention, this process is repeated with the lignocellulosic material at least once or more at a temperature not greater than that at which the lignocellulosic material was initially treated in steps {b' and [c--.

In one embodiment of the invention, lignin is solvent extracted from the particulate material exiting the extrusion die, preferably with a solvent selected from the group consisting of ethanol, methanol, and acetone.

Wet alcohol insolubles may be separated from the particulate material prior to lignin extraction with acetone.

The aqueous material may be extracted from the particulate material before or after the lignin is solvent extracted therefrom. This solvent extracted lignin is substantially in granular form with particles in the range of 1 to 10 microns and has a purity on the order of 9% by weight;
It is easily chemically reactive, thermoplastic, and has an infrared spectrum close to that of so-called natural lignin. Hemicellulose is extracted from the lignocellulosic material by hydrolysis with hot water prior to packing the lignocellulosic material into a pressure vessel.

Preferably when the lignocellulosic material is wood,
600 to 70 to minimize hydrolysis in the pressure vessel.
Rapidly fill with steam at pressures in the range of 0 psi. More particularly when the lignocellulosic material is wood, this pressure vessel is rapidly filled with steam, preferably at a pressure in the vicinity of 65 mm sj.

Preferably, when the lignocellulosic material is annual biomass, the pressure vessel is
Rapid steam filling at pressures in the range of 0 psj, more particularly around 550 psi.

In certain embodiments of the invention, the pulverized gnocellulosic material is made wet with water when packed into a pressure vessel, preferably near fiber saturation.

In one embodiment of the invention, when the lignocellulosic material is an annual plant, the pressure vessel is rapidly filled with steam at a pressure of about 55 capes, and after about 40 seconds, the steam pressure is increased to a higher pressure. It builds up quickly and releases the material for extrusion as soon as this high pressure is obtained.

In another embodiment of the present invention, when the lignocellulosic material is wood, the pressure vessel is rapidly filled with steam at a pressure in the vicinity of 65 Cape si and the steam pressure is rapidly increased to a higher pressure after about 4 psi. and as soon as this high pressure is obtained, the material is released for extrusion.

According to a second aspect of the invention there is provided a granular product produced by the process according to the invention.

The product according to the invention has the desired properties that a significant portion of the Q-cellulose present in the lignocellulosic material is now accessible in digestible form for microbial digestion; It was found that a negligible decrease in the fermentation value or content of mycellulose occurred.

This product is thus useful for: 'i'
as feed for anti-anchor animals;

The products of the invention also have the following desirable properties: [a
) the main part of the sugars of the hemicellulose can be removed, e.g. by thermal DK, and 'b} the main part of the lignin can be removed by solvent extraction, e.g. using ethanol, methanol or acetone, e.g. The cellulose-rich material is left for use as a pulp in a cellulose solution or directly solubilized using a suitable cellulose solvent.

As used herein, "lignocellulosic material" includes cultivated plant materials such as oat hulls, corn stalks, bagasse, wheat stalks, rice stalks, oat stalks, bare wheat stalks, and various woods, especially hardwoods.

In the accompanying drawings, the pressure vessel 2, the star-shaped extrusion die outlet 4, the extrusion die closure plug 6, the filling end closure flap 8 and the steam inlet orifices 10 to 12 are shown. The pressure vessel 2 has a neck portion 14 leading to the die 4 and inlets 16 and 18 for a temperature probe (not shown).

The front end of the pressure vessel 2 including the die outlet 4 has a flange 2
0, to which is sealed a curved impingement tube 22 whose cross section gradually decreases in the downward flow direction.

This curved impingement tube 22 has a spindle inlet sleeve 24 with a flange 26. Air ram 28 is attached to flange 26 and has a die closure plug 30 mounted on spindle 32 of ram 26. pressure vessel 2
The rear end is sealed to the rest by flanges 36 and 38 and is secured thereto by hinge 401 and clamp 4.
2 has a fill end closure flap 8 which can be sealed.

In operation, this filling end closure flap 8 is opened and the IJ gnocellulosic material in comminuted form is filled into the pressure vessel 2 and the die closure plug 30 closes the die outlet 4.

Pack the lignocellulosic material into the pressure vessel 2 using a rod (not shown). In the pressure vessel 2 completely filled with lignocellulosic material, the die closure plug 3 is sealed by the air ram 28 and the closure plug 8 is sealed to the rear end 34 by the clamp 42, and then the source (not shown) ) to steam inlet orifice 10 without, 12
to the pressure vessel by injecting steam into the pressure vessel.
The temperature of the lignocellulosic material is reduced to 185 °C to 240 °C at a pressure within the range of psj, preferably 500 °C to 70 °C, and for 60 seconds or less (preferably 49 °C or less).
The hemicellulose and lignin in the lignocellulosic material are plasticized by charging steam at a temperature in the range of 234 qo, particularly sufficient to raise the temperature to 234 qo. Row 6 and 18
I in the pressure vessel using a temperature probe (not shown) to
J Monitor the temperature of the gnocellulosic material to determine when the lignocellulosic material reaches the selected temperature. As soon as the IJ gnocellulosic material in the pressure vessel 2 reaches the desired temperature, the air ram 28 is actuated to close the closure plug 3.
0 and momentarily open the die outlet to the atmosphere, so that the lignocellulosic material is extruded through the die outlet 4 in a plasticized state and at extrusion pressure, and along the curved impingement tube 22 preferably milli-grid. is flashed into the atmosphere.

This sudden release into the atmosphere is preferably 5 per square inch.
Extrude the lignocellulosic material in a plasticized state at pressures in the vicinity of 0.00 to 700 lbs., and granular material having the appearance of potting soil that stains fingers brown and having a specific gravity high enough to sink like a stone in water. will occur. Although this curved impingement tube is not required, it has the advantage of utilizing a fraction of the extrusion force to further fragment the lignocellulosic material in addition to the fragmentation obtained from the extrusion tube.

A possible explanation for the present invention is that in the lignocellulosic material in the plasticized state, the lignin, hemicellulose and cellulose are softened and thereby structurally weakened, so that during extrusion this softened material undergoes severe mechanical shock, which causes the lignin, It has the effect of cutting crosslinks between hemicellulose and cellulose.

Once the weakened and cut gnocellulosic material exits the die outlet 4, the instantaneous drop in pressure causes this weakened and cut gnocellulosic material to rupture, thereby reducing the hemicellulose. molecular weight and at the same time cause substantial degradation of the primary fiber structure, which in turn leaves a substantial area of the Q-cellulose microfibrils, in some applications of the invention, susceptible to fermentation agent attack. expose for the sake of The basic crystal structure of cellulose microfibrils is preserved.

A very high degree of deassociation of lignin is obtained. When this process is carried out at temperatures above 243° C., the xylose component likely decomposes to furfural and valuable digestible material is lost from the material. Decomposition also causes toxicity to microorganisms. One purpose of this method is to make the Q-cellulose very accessible to microorganisms and to minimize the effect of hydrolysis on hemicellulose, so that the time to obtain temperature does not exceed 1 minute, and even better It is important that the amount should be within the range of 5 to 5 minutes. The pressure is not critical, but this is 220-23
Influence the time to obtain the optimum temperature of 0. This step is repeated at least once or more at the same or lower temperature and shows further increases in digestibility improvement. Tests were conducted to confirm the present invention using the apparatus shown in FIG. 1 having the following dimensions: Internal diameter of main part of pressure vessel 2 = 7 inches
9o-5 sail) Minimum inner diameter of neck of pressure vessel 2 = 3 takain (82,5 skin) Internal length of pressure vessel 2 = 45 inches (1.14) Diameter of each steam inlet 10 and 12 =3
/4 inch (13 snouts) Steam inlet 1 Diameter of 1 = 2 inches (0.8 feet) Die outlet orifice is 0.8
It was star-shaped with five equally spaced points giving a cross-sectional area of square inches (11.6 square meters).

In Tables 1 to V below, the temperature is the temperature of the material in the pressure vessel 2 when the closure plug 30 is removed, and the vapor pressure is the vapor pressure in the pressure vessel 2 at exactly that time.

The time is the time during which the temperature of the lignocellulosic material rises to the indicated temperature and is then extruded from the pressure vessel.
This table shows the results of tests of products of the invention compared to tests carried out at higher temperatures than those according to the invention. In this study, digestibility was evaluated by two methods, in vitro and in vivo tests using anti-maritime microflora, and secondly by treatment with cellulose enzymes, and the results are shown in Tables 1 to V. are shown respectively. The same IJ tested for all in the table
The gnocellulosic products are designated in the same manner, eg in each test A designates the same lj gnocellulosic material, the same hereafter.

Table 1 *O-cellulose digestibility was measured in vitro using anti-war animals.

From Table 1, there is a sharp drop in Q-cellulose digestibility at material temperatures above about 240°C, and this represents about 65% by weight of the total digestible carbohydrates present in the starting material, whereas It turns out that something expensive is necessary. Analyzes (bran content, arbitrary units plotted against temperature in °C) indicate that Q-cellulose is not destroyed by this treatment and therefore the loss of digestibility in vitro by ruminants is due to some external factors. It is shown that this is caused by

Chemical properties of treated wood chips The main objective of the following study was to compare the results of the method under different reaction conditions.

The experiments carried out were of an exploratory nature and the samples used were those obtained in tests A to D and also treated poplar and treated barley stalks which were then fed to sheep in the digestive test. did. These tests included a wide range of reaction conditions.
The results of the analysis are shown in Tables B to N. In general, the results of the study show that these samples can be classified into two categories.

1 Wood treated according to the invention at temperatures below 240 oo (A, B and C) 2 Wood treated at temperatures above 240 oo (D and supplied wood).

Samples from the first category are found to be a better source of carbohydrates than the second category, as the high temperatures required to produce the second group cause extensive decomposition of the pentose sugars present in the wood. .

Method Sample Preparation Samples (A, B, C, D and supplied wood) were dried overnight at 1050 °C to constant weight.

Samples (10
evening) was extracted.

The wood fibers were dried and the extracted material was weighed. The aqueous extract was diluted 250' and an aliquot of this extract was analyzed. Analytical method used for the sample Phenol sulfuric acid colorimetric method (M.D. Dubois)
) etc., Anal. Chem. 28 (3) 350 (195
Total carbohydrates were measured by Somogyi (Som 6)).
ogyi) Copper titration method (Methods in Ca
Reducing sugars were determined by Hydrolytic Chemistry, Volume 1, Page 380, 1962 (Academic Press), and total sugars were determined by gas chromatography after hydrolysis using Tappi method T24 Sam-75. It was measured.

Table 0 All percentages are by weight of dry material.

x Percent water extract based on the weight of oven-dried wood fibers + gas chromatography - calculated using the full discount from the analysis and based on the weight of oven-dried material.

Table m 1. Total carbohydrates determined by phenol-sulfuric acid colorimetry using crucose as the reference sugar.

2. Reducing sugar measured by Nmogi trace copper method K.

3. Total sugar measured by gas chromatography using Tabbi method T249pm-75 after decomposition from horsetail over medium heat.

Section IV Discussion The pH values of the samples ranged from 3.6 to 4.1.

This range appears normal for samples from wood materials treated with high pressure steam (600 si). Under the reaction conditions listed in the introduction, the acetyl groups present in the wood are expected to hydrolyze to release acetic acid, which decreases the pH (ie increases acidity). This acidity helps hydrolyze the lignocellulosic material and increase the water extractable material in the wood. This method uses 18
None, it is shown that 34% is solubilized (Table D)
.

Wood usually contains between 2% and 3% water solubles. Category 1 samples (A, B and C) range from 29.0 to 34.
It has water extractables ranging from 7%, while category 2 samples 10 and supplied wood) have only 18.1 to 21.6%. A low percentage of category 2 extracts resulted from the decomposition of the carbohydrate material (pentose) due to the high reaction temperature. For category 1 samples, the reducing sugar content of the extract is approximately half of the total carbohydrate content (Table m).

This indicates that the carbohydrate material present has an average degree of polymerization of 2. For category 2 samples, the reducing sugar content of the extract is approximately equal to the total carbohydrate content. This indicates that all solubilized carbohydrate material is converted to monomers. Gas chromatography analysis of the sugars present in the water extract is shown in Table N.

All samples tested had roughly the same amount of hexoses (malenose, galactose, glucose), but sample D (and the supplied wood) had a much lower pentose content (arabinose and xylose). These results indicate that there is a transition point (range) for pentose destruction at temperatures between 238 and 24600. Thus, wood fibers treated above this transition temperature have a lower fraction of water-soluble extractables than samples treated below this transition temperature, because the furfural produced by the decomposition of pentose sugars is absorbed during the bursting process. “Flash-off”
This is because it will be done. Decomposition of hexose sugars does not appear to be a problem at the temperatures tested, primarily due to their high stability against thermal decomposition. Destruction of pentose sugars above the transition temperature reduces the amount of sugars available for digestion by about 10% based on the weight of wood treated.

Analysis of the water-soluble extract shows that above the transition temperature only 2% and 3% of the fiber weight constitutes solubilized carbohydrates (e.g. D and fed wood), but below the transition temperature 10% of the fiber weight
None, 14% solubilized carbohydrates (e.g. A, B and C)
). This weight (sugar) loss is caused by the destruction of xylose and arabinose. This loss of 10% of the weight of carbohydrate material is supported by the study below, i.e. the supplied wood (treated with 24600) was treated with maxazyme (commercially available Trichodermaviride cellulase). It was found to have a final reducing sugar value of 33.8% after set time digestion while all other wood samples (treated below 238°C) were 42.8% and 47%.
It had a return value of 4%. Sample D was not tested in this manner. Treated wood samples were hydrolyzed using State Day 2S04 at 10,000 to determine whether chemical methods can be used to correlate digestibility with the rate of carbohydrate release upon hydrolysis.

The results of this study are shown in Figure 2, where the dried product (R
The weight percent of reducing sugars by weight of S) is plotted against the digestibility time in minutes (TM). In Figure 2, the graph shows the following: ×-1 × is sample A in Table W, △---△ is sample B in Table N, and ○ core 40 is in Table W. Sample C, 11-10, is sample D in Table W, and Low is the wood (poplar) supplied in Table W.

Sample D and the supplied wood have slightly closer reduction values than the other three samples, probably because the pentose in these two samples is degraded and unavailable for hydrolysis. . The difference in final reduction value (2 hours) and rate of healthy release is due to the fact that roughly equal amounts of cellulose are exposed to the wood fibers of each sample (i.e., the accessibility of each fiber to the acid is the same for all samples). something). Since the accessibility of cellulose is the same, it is expected that the digestibility of the fibers will be the same, but this will not necessarily be the case since the accessibility of cellulose enzymes to cellulose fibrils is much more limited than acids. Conclusion 1 Treatment of wood chips with high pressure steam results in hydrolysis of acetyl groups and degradation of hemicellulose present in the wood, releasing acetic acid and uronic acid.

2 Processing of hard wood chips by extrusion method
Converts between 34% and 34% by weight into hot water extractable.

3 Solubilized carbohydrate materials appear to exist in monomeric and dimeric forms.

4 A temperature of about 24,000 ℃ appears to be the transition temperature,
Above that point, substantial decomposition of the pentose occurs.

5 Above this transition temperature, destruction of pentose sugars reduces the amount of sugars available for digestion by about 10% of the weight of treated wood.

6 The portion of cellulose "exposed" on the surface of the crushed fibers appears to be roughly the same for all samples tested.

Enzyme Digestibility Characteristics of Treated Wood Chips Table V below shows the results of enzymatic digestibility measurements with Trichoderma viride cellulase of aqueous suspensions of the products.

Table V★ Enzyme digestion conditions for which these samples were tested twice: Aqueous suspension 1% by volume Pulp consistency: Aqueous suspension 0. String volume % pH of aqueous suspension: 5.0 Temperature of aqueous suspension: 3000 Incubation: Continuous mixing time 2 Misakitera (1 hour) Figure 3 is based on the results shown in Table V and Figure 2 shows the dry product weight percent of the resulting reduced material, such as glucose, plotted against the temperature (°C) at which the lignocellulose was extruded.

In Figure 3, the graph shows: - After one digestion ~ By digestion only - × Before one digestion Figure 4 is based on the results shown in Table V and the temperature at which the rig/cellulosic material was extruded. The amount of bran bran is shown in arbitrary units after enzyme digestion, plotted against (SC).

In Figure 4, Grahn shows that: - Monohexose - Pentose Figures 3 and 4 show that the yield of hexose remains unaffected by the temperature at which the lignocellulosic material is extruded. , whereas the pentose yield begins to rapidly decrease towards zero at temperatures above 240°C.

These results compare well with those shown in the tests described above. In Table V, Run F was double treated at both temperatures indicated and this further improved digestibility.

Tests have shown that a die with an orifice cross-sectional area of 0.8 square inches works well. Although the shape of the die orifice is not critical, it was found that the star-shaped orifice gives a large boundary to the cross-sectional area, so that a large amount of mechanical deformation occurs with good disruption of the cross-links between lignin, hemicellulose and cellulose. The preferred temperature is 200
None, 2340○, especially 23400.

The following morphological analyzes were performed on treated poplar wood and barley stalks.

- Freeze-drying to determine the water content of the sample while preserving its structure.

- Light microscopy observation of the lyophilized product.

-2 Unique boiling water extraction.

-X of the original product, lyophilized product and extraction residue
Stereotype diffraction by lines.

Observation of freeze-dried Kenkichi fruit using a scanning electron microscope.

1 Freeze-dried sample Moisture content Poplar wood 48 Mother weight% Barley stem 45. Box Weight % After freeze-drying, each of the two samples exhibits a dark brown color and a greyish reflection.

A strong and acidic odor is characteristic of carbonized sugars and carbohydrates.

2 Optical microscope observation of freeze-dried sample The fibrous structure of cellulose can be recognized, but the fibers are clearly incorporated.

The fibers appear to be linear or break during processing: these features (lumens, punctuation) are still visible. The presence of wood conduits allows for the foliate nature of the wood used. This extraction was carried out with the help of a Soxhlet tube under water reflux at 100° C. for 24 hours.

In fact, after 2 unique moments, it appears that the extraction is complete since the extraction solution is clear in the last cycle. poplar wood 3
0.0% extracted barley stem 36.8% extracted sample: The characteristic odor of the sample is reduced by the extraction residue, but the color appears to be the same.

The weak chains of carbohydrates and lignin pass into solution, but the residue contains much more lignin, insoluble in water, at 10,000. To summarize: Residue = cellulose + long chains of hemicellulose 1 Lignin extract = carbohydrates from hemicellulose hydrolysis + already carbonized sugars 1 slight trace of lignin The cold extraction solution is colored, but also Contains a large percentage of non-melting material.

4 X-ray analysis Cellulose is found in crystalline form in the crude product, lyophilized product and extraction residue.

This confirms the presence of long cellulose chains (in the form of somewhat incised fibers after sustained treatment). There were no significant differences between the treated poplar wood and barley stalk samples.

5 Scanning Electron Microscope No. 5 No. 8 In FIG.
350), supplied wood (x2640), supplied stem (
×6380) and the supplied stem (×2760) are shown, respectively.

These photographs show the high accessibility of Q-cellulose microfibrils as well as the extent of lignin separation, as indicated by spheres of gunin spreading through the material. It is observed from Figures 5 to 8 of each of the lyophilized samples that longitudinally torn fiber fragments are visible.

Spherical particles, probably lignin, are expelled from the fibers and released as droplets during processing. Conclusions from the morphological analysis Greater accessibility of the fibers due to "tearing" and cleavage of the secondary walls explains the increased enzyme accessibility occurring in the treated material.

In fact, the specific surface area of the fiber increases obviously (wall cleavage)
. This cleavage appears to be due to the rupture of the middle leaf: the lignin is then expelled and thereby dissociates from the wall.

On the other hand, at the microfiber level, cellulose crystallinity is preserved as inferred from X-ray diffraction analysis.

Separate tests were conducted to investigate the ease of bleaching lignin from treated poplar wood and barley stalks using ethyl alcohol and to determine the lignin yield of this extraction.

As shown in FIG. 9, treated wet poplar wood (55% by weight combined water content), (referred to as WAP), was equally divided into two parts.

Each portion was extracted three times with 95% ethanol at room temperature (methanol can also be used as well as other relevant solvents). The mixture was continuously stirred in a plastic container with an air-operated impeller. The extraction time and the volume of ethanol used were as follows: 1st extraction: 12 so;
0. Second extraction time: 12 evenings, 2 hours Third extraction: 7 evenings, 2 hours It was filtered, separated by far-D separation, denoted C, and then concentrated to a deep black solution.

The sediment from the centrifuge bottle was washed with fresh ethanol and extracted with approximately 500 g of benzene in a separatory funnel. F6
A green fat (fraction No. 6) designated by F7 was obtained from the benzene layer, and a gray powder designated F7 (fraction No. 7) was obtained from the aqueous layer by concentration. Approximately 3 g of acetone was slowly added to the concentrated alcoholic extract that was swirled in the flask. The mixture was left overnight and then filtered to yield a wet acetone-insoluble precipitate designated F2 (Fraction No. 2). The acetone filtrate was concentrated to about 1 ml, slowly added to 14 ml of water, and stirred in a plastic container. The water-insoluble precipitate designated as F3 (Fraction No. 3) was filtered and extracted twice with petroleum ether, designated as F8 (Fraction No. 3).
8) was produced. The aqueous solution was evaporated for about 1.5 minutes and extracted twice with ethyl acetate to obtain an ethyl acetate soluble fraction (Fraction No. 5) designated F5 and a fraction remaining in water (Fraction No. 5) designated F4. No. 4) was obtained. Initially, the wet weight of wet poplar wood product (WAP) is 3.252
The oven dry weight was 1.463 mm.

The table below shows the weight for each fraction obtained from the method described with respect to FIG.

A similar leaching process was carried out on the treated wet barley stalks designated WBSP in Table 10, Figure 10.

In FIG. 10 the same fractions are designated with the same reference numerals as in FIG. 9 and the foregoing description generally describes them and depends on how they were obtained.

The initial string weight of the wet barley product was 137.4 mm and the oven dry weight was 88.97 mm.

This initial extraction was carried out in 1000' of 95% ethanol at each stage.
It was a two-step process using . Fraction no. The concentrated alcoholic extract of 1(F,) was concentrated to almost dryness and the acetone was added to fraction no. 2 (F2).

Fraction no. The acetone filtrate of F2 was concentrated to above about 120 ml, precipitated and added to 1.8 ml of water.

This ethyl acetate soluble fraction No. 5 (F5) was extracted twice with ethyl acetate. The table below shows the 10th plate.
Each fraction obtained in the manner described for the figure is given a weight.

Skin surface lignin is probably present in fractions 1, 2 and 4 in very small amounts.

The infrared spectra of these fractions had absorption characteristics of carbohydrate-rich materials. Fractions 3 and 4 were lignin-owned. Fraction 3 Klason (K1asou) on barley stalks
) The lignin content is 929.9% by weight, and the WA
It was 93.1% with respect to P. These fractions had the infrared absorption properties of natural lignin. It is concluded that a very large part of the lignin content of the ruptured material can be easily extracted with ethyl alcohol. cell. The dissociation of lignin from hemicellulose and hemicellulose is probably caused by the method of depolymerizing lignin according to the invention. Ethanol and acetone can be easily recovered with this simple extraction, providing a very effective method of obtaining lignin. By this method, lignin is dissociated from lignin carbohydrate complexes (LCC), for example after treatment of wood and stems.

Separate tests were performed to show that most of this natural lignin can be easily extracted with acetone. In this test, A
70.5 hours of treated wet poplar wood (55.4% moisture, oven dry weight 31.44 hours) designated W was extracted three times with acetone into a 500 mm top beaker.

Approximately 250' of acetone was used in each extraction. The mixture was stirred with a glass rod for approximately 5 minutes and then filtered. The third extract was clear and bright in color. The extracts were combined and concentrated on a rotary evaporator to approximately 160'. Thus,
An acetone insoluble material (mountain) was obtained and an acetone soluble material (AS) was obtained in fraction 1 (F,). Care was taken to avoid overheating the solution near the end of evaporation which would cause the lignin suspension to coagulate and form sticky clumps. The concentrated extract was slowly poured into cold water (1000) overnight and stirred in a container. The lignin wet mixture was then filtered through slow-flow filter paper, dried at room temperature, and 6.55 kg of water-insoluble precipitate (WIP) Q dry lignin-rich powder was obtained in fraction 2 (F2). This is water soluble (WS)
represents 20.8% of the total dry material leaving fraction 3 (F3) remaining in water. A similar extraction was performed using treated barley stalks designated BS.

A total of 1050 skins were extracted three times with a wet burst BS of 97.0 mm (moisture 50.0%, oven dry weight 48.5 mm). The extract was concentrated to about 200 mg and slowly poured into cold water. 7.2 kg of dry lignin-rich powder was obtained, which was approximately 14.8% of the total dry material. The ratio of solvent volume to material weight is chosen arbitrarily so that the mixture is not too sticky to stir.

The concentration of DM about 12/100 ml is probably dilute enough to stir in the glass. Since the extracted gunins are highly soluble in acetone and leaching is rapid, very large process efficiencies would be expected. However, equilibrium data for the acetone extraction is needed to determine solvent volume requirements and number of stages. Due to the presence of water in the ruptured material, some low molecular weight hemicellulose is also leached out. Much smaller amounts of other waxes, phenolic resins and extractives were also extracted. (AW only)
remained in the lignin-rich area and accounted for less than 1% of the total village fee. Figure 11 shows the leaching sequence of AW and Shigeru. The table below shows the amounts of each fraction and adds notes regarding these.

Klason lignin measurements of the top lignin-rich fraction showed that the lignin-rich fraction contained about 93% lignin.

A minimum of 90% lignin yield can therefore be expected from the leaching of wood and stems treated according to the invention with acetone. The solvent can be easily recovered with little heat requirement, which makes this method even more attractive. Another advantage is that the acetone-extracted material is largely lignin-free, thus increasing its value as a fermentation substrate or source material. FIG. 12 shows a simplified schematic diagram of the acetone extraction of lignin from, for example, treated wood and stems. 12th
In the figure, processing material M is fed to extractor ES and fresh acetone (ethanol or methanol) is fed to tank T.
supplied to

From the tank T, acetone is continuously fed to the extractor ES and from there overflows to the first evaporator EVI, while from the extractor ES a downward stream flows to the first filter FI. The filtrate from the first filter FI is sent to the first evaporator EVI, while the residue from the first filter FI is dried in the dryer D to yield the carbohydrate-rich solid SI. First evaporator EV
The recovered acetone from I and dryer D is returned to tank T.
The retentate from the first evaporator EVI is mixed with water W in the settler P. The mixture from precipitator P is sent to a second filter F3, from which filtered gunin FL of >90% purity is obtained. The residual liquid from the second filter F2 is transferred to the second evaporator EV.
2, where the carbohydrate-rich solution is obtained S2,
Meanwhile, from there the evaporated product is sent to the distillation unit DU,
From there W2 is separated from the acetone and the acetone is returned to tank T. Gnin produced according to the invention by solvent extraction from treated materials can be thermally plasticized and extruded as lignin filaments, which can be carbonized in the presence of heat to form carbon fibers.

Carbon filaments produced in this way can be used, for example, in air or water filtration.

[Brief explanation of the drawing]

FIG. 1 is a side cross-sectional view of a pressure vessel with an extrusion die outlet, which was used to confirm the invention. FIG. 2 is a graph showing the rate at which reducing sugars are released by hydrolysis from the product produced by this extrusion method. FIG. 3 is a graph of the enzymatic digestibility of reducing substances such as glucose produced by different temperatures at which the lignocellulosic material was extruded. FIG. 4 is a graph of the enzymatic digestibility of the sugar content produced by different temperatures at which the lignocellulosic material was extruded. 5-8 are scanning electron micrographs of products according to the invention produced using the apparatus shown in FIG. FIG. 9 is a flow diagram for solvent extraction of lignin from treated poplar wood. FIG. 10 is a flow diagram for solvent extraction of lignin from treated barley stalks. FIG. 11 is a flow diagram for the solvent extraction of lignin from treated poplar wood and barley stalks using acetone as the solvent. FIG. 12 is a flow diagram for the acetone extraction of lignin from, for example, treated wood or stems. Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8

Claims (1)

[Claims] 1. A method for treating lignocellulosic material, comprising: (a)
a) packing the lignocellulosic material in ground form into a pressure vessel with a closed extrusion die outlet; (c) as soon as the lignocellulosic material is in a plasticized state, open the extrusion die outlet and release steam from the pressure vessel through the extrusion die outlet to the atmosphere; in a lignocellulosic material, comprising momentarily extruding a lignocellulosic material in a plasticized state, whereby said material, in which the lignin has been separably altered from cellulose and hemicellose, is discharged from an extrusion die in granular form. A method for separably converting lignin from cellulose and hemicellulose. 2. A method according to claim 1, in which a lignocellulosic material is extruded onto the impingement surface. 3. A method according to claim 1, in which the pressure vessel is rapidly filled with steam so as to bring the lignocellulosic material to a temperature in the range of 200-238C within 45 seconds. 4. Process according to claim 1, in which the pressure vessel is rapidly filled with steam so as to bring the lignocellulosic material to a temperature of 234° C. within 45 seconds. 5. According to claim 1, steps (a) to (c) are repeated at least once or more on the lignocellulosic material at a temperature not higher than that at which it was initially treated in steps (b) and (c). Method. 6 In the method for treating lignocellulosic material, (a
) packing the lignocellulosic material in ground form into a pressure vessel having a closed extrusion die outlet; (b) at least (c) As soon as the lignocellulosic material is in a plasticized state, open the extrusion die outlet and release the pressure vessel through the extrusion die outlet to the atmosphere; extrusion of a lignocellulosic material in a plasticized state, whereby said material in which the lignin has been releasably converted from cellulose and hemicellulose, is discharged from an extrusion die in granular form, and (
d) A method for solvent extraction of lignin from the granular material released from an extrusion die. 7. A method according to claim 6, wherein the lignin is solvent extracted with a solvent selected from the group consisting of ethanol, methanol and acetone. 8. Process according to claim 7, in which wet alcohol insolubles are separated from the granular material with alcohol before the lignin extraction with acetone. 9. A method according to claim 6, wherein after the lignin extraction the wet organic solvent insolubles are separated from the lignin solvent by filtration. 10. A method according to claim 6, wherein water solubles are extracted from the granular material with water before the lignin is solvent extracted. 11. A method according to claim 6, wherein water solubles are extracted from the granular material with water after the lignin has been solvent extracted. 12 The extracted lignin is substantially in granular form with particles in the range of 1-10 microns, has a purity on the order of 93% by weight, is readily chemically reactive, thermoplastic, and has a so-called A method according to claim 6 having an infrared spectrum close to that of natural lignin. 13 In the method for treating lignocellulosic materials, (
a) hydrolyzing the lignocellulosic material in ground form with hot water to extract the hemicellulose; (b) packing the lignocellulosic material in ground form into a pressure vessel having a closed extrusion die outlet; (c) 185~2 within seconds
(d) plasticizing the lignocellulosic material by rapidly charging the pressure vessel with steam at least 500 psi to bring the lignocellulosic material to a temperature in the range of 40°C; As soon as the extrusion die outlet is opened and the plasticized lignocellulosic material is extruded from the pressure vessel through the extrusion die outlet to the atmosphere, the lignocellulosic material in the plasticized state is separably converted from cellulose and hemicellulose. A method for separably converting lignin from cellulose and hemicellulose in lignocellulosic materials, comprising expelling the materials from an extrusion die in granular form. 14. A method according to claim 1, wherein the lignocellulosic material is wood and the pressure vessel is rapidly filled with steam at a pressure within the range of 600-700 psi. 15. A method according to claim 1, wherein the lignocellulosic material is wood and the pressure vessel is rapidly filled with steam at a pressure in the vicinity of 650 psi. 16. A method according to claim 1, wherein the lignocellulosic material is annual biomass and the pressure vessel is rapidly filled with steam at a pressure in the range of 500-600 psi. 17. The method according to claim 1, wherein the lignocellulosic material is annual biomass and the pressure vessel is rapidly filled with steam at a pressure in the vicinity of 550 psi. 18. A method according to claim 1, in which the lignocellulosic material in pulverized form is moistened with water when it is packed into a pressure vessel. 19. A method according to claim 18, wherein the lignocellulosic material in fine powder form is moistened with water to saturate the fibers when it is packed into a pressure vessel. 20 The lignocellulosic material is an annual plant material, the pressure vessel is rapidly filled with steam at a pressure in the vicinity of 550 psi, and after about 40 seconds the steam pressure is rapidly increased to a higher pressure and upon obtaining said high pressure A method according to claim 1, wherein the material is released for extrusion. 21 The lignocellulosic material is wood, the pressure vessel is rapidly filled with steam at a pressure in the vicinity of 650 psi, and after about 40 seconds the steam pressure is rapidly increased to a higher pressure and as soon as said high pressure is obtained the material is A method according to claim 1, which is discharged for extrusion. 22 In the method for treating lignocellulosic materials, (
a) filling a pressure vessel with a closed extrusion die outlet with the lignocellulosic material in ground form; (b) loading the lignocellulosic material in a small amount so as to bring the lignocellulosic material to a temperature within the range of 185-240°C within 60 seconds; (c) As soon as the lignocellulosic material is in a plasticized state, open the extrusion die outlet and release the pressure vessel through the extrusion die outlet to the atmosphere; (d
) The granular material released from the extrusion die is treated with water to extract the hemicellulose, treated with an organic solvent to extract the lignin, and treated with a cellulose solvent to extract the cellulose.