JP2009296919A - Method for liquefying cellulose-based biomass - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for simply and easily liquefying a cellulose-based biomass into monosaccharides and liquid compounds except the monosaccharides in an extremely high inversion ratio without using a liquid strong acid such as sulfuric acid etc. <P>SOLUTION: The method for liquefying a cellulose-based biomass includes a process for reacting a cellulose-based biomass raw material with a functional group on the surface of a carrier and hydrothermally decomposing the cellulose-based biomass raw material. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a method for liquefying cellulosic biomass. More specifically, the present invention relates to a single treatment of cellulosic biomass with a solid acid and a method for liquefying cellulosic biomass by hydrothermal decomposition.

The introduction of renewable and biomass resources that fix carbon dioxide is being considered. Promising biomass resources include cellulosic biomass such as forest trees and sugarcane, and waste such as municipal waste. In order to use these biomasses as energy, it is important to develop a process for converting the raw material biomass into energy with high efficiency. As a method for converting biomass into energy, there are a combustion method, a thermochemical conversion method, and a biological conversion method. The thermochemical conversion method includes processes such as gasification, liquefaction, and pyrolysis of biomass resources.

For example, in the liquefaction process, important bioethanol production competes with food because it mainly uses sugarcane and corn as its raw material. There is also a limit to the supply of sugarcane and corn. For this reason, ethanol production using cellulosic biomass, which is a non-edible biomass resource (woody and herbaceous biomass) such as stems and leaves of plants not used for food, is expected. In order to produce ethanol using cellulosic biomass, it is necessary to hydrolyze cellulosic biomass into its constituent molecules, cellulose and hemicellulose, to produce monosaccharides. However, since cellulose and hemicellulose have strong molecular bonds, it is difficult to hydrolyze biomass to produce monosaccharides such as glucose, xylose, and mannose. Therefore, in ethanol production using cellulosic biomass as a raw material, how to saccharify cellulose is extremely important.

Cellulose saccharification methods are roughly classified into enzyme methods using enzymes such as concentrated sulfuric acid method, diluted sulfuric acid method and cellulase. First, in the concentrated sulfuric acid method, biomass is brought into contact with a concentrated sulfuric acid solution having a weight percent concentration of 70% to 80% to decompose into cellulose and hemicellulose. Then, the obtained cellulose and hemicellulose are hydrolyzed under normal pressure and a temperature of around 70 ° C. After hydrolysis, monosaccharide and sulfuric acid are separated, and sulfuric acid is reused.

In the dilute sulfuric acid method, biomass is hydrolyzed using several percent sulfuric acid under conditions of a temperature of 150 ° C. to 250 ° C. and a pressure of 1 to 2 MPa, and monosaccharides are obtained after hydrolysis. In this method, since concentrated sulfuric acid is used instead of concentrated sulfuric acid, neutralization is performed with an alkaline solution after use of sulfuric acid without collecting sulfuric acid. These cellulose saccharification methods have the advantages of high reactivity with cellulose, high reactivity even with strong substances, and high degradation rate.

On the other hand, improving the sugar concentration in the acid saccharification solution, concentrating and recovering the sulfuric acid after use, reducing the energy for reusing the sulfuric acid after use, and the process engineering of the equipment in the pretreatment process of biomass It has problems such as improvement. That is, conventional acid treatment methods such as concentrated sulfuric acid method and dilute sulfuric acid method have sufficient reactivity with biomass, but have a problem that reaction selectivity with biomass is extremely low. In addition, since biomass is treated with sulfuric acid, an acid-resistant reactor is required, and a process for neutralizing and recovering the sulfuric acid after use is required, so that the cost of the reactor is high.

On the other hand, the enzyme treatment method is a method for saccharification by reacting an enzyme with biomass. In this enzyme treatment method, by using an enzyme having a high activity, the decomposition reaction proceeds selectively under relatively mild reaction conditions. Therefore, the enzymatic saccharification method has an advantage that the safety during the reaction is high as compared with the acid treatment method using a strong acid such as sulfuric acid. However, “cellulase”, which is a cellulose-degrading enzyme generally used in the above-mentioned enzyme treatment method, is very expensive. In addition, when the crystal structure of biomass is very strong, not only many enzymes but also dilute acid treatment and other pretreatments are required for saccharification.

In other words, the enzyme treatment method has a problem that the reaction efficiency is extremely low and the reaction rate is slower than the acid treatment method because of the biological method based on the enzyme reaction. Furthermore, cellulase, which is an enzyme used in the enzyme treatment method, is extremely difficult to recover once used in a saccharification reaction. In the case of recovering enzyme cellulase, as with the recovery of sulfuric acid in the above acid treatment method, it is costly and the enzyme search process is complicated (for example, Non-Patent Document 1).

From such a viewpoint, a saccharification method in which hydrolysis and enzyme treatment are performed is disclosed as a method for producing ethanol from woody biomass (Patent Document 1 and Patent Document 2). However, in the above method, since sulfuric acid or an alkaline aqueous solution that is a strong acid is used for the hydrolysis reaction of biomass, there is still a problem that a recovery or neutralization step of sulfuric acid is still necessary as described above.

In the method for producing ethanol from the woody biomass, an enzyme treatment is an essential step after the acid or base treatment, and the treatment step becomes complicated. In addition, as described above, there is a problem that the enzyme is expensive and its recovery is expensive.

In addition, this patent applicant discloses the following technical literature as a publication in which the literature well-known invention relevant to this invention was described.
JP 2008-43328 A JP 2006-87350 A "Concentrated sulfuric acid biomass ethanol production process" Daisuke Taneda 2006, (Cellulose Communication, Vol. 13, No. 2, pp. 49-52, 2006), Cellulose Communication. Vol.13 No2, p49-p52 ( 2006) “Preparation and properties of immobilized cellulase using alumina particles as a carrier” Osamu Umakaki, Journal of Chemical Engineering, Vol. 22, No. 4, p801-p806 (1996)

In view of the situation as described above, an object of the present invention is to provide a method for easily and easily liquefying a cellulosic biomass at a very high conversion without using a liquid strong acid or strong base such as sulfuric acid. It is in. Moreover, the subject of this invention is providing the method of liquefying the cellulose biomass which is easy to isolate | separate from monosaccharides and liquid compounds, such as glucose and xylose, produced | generated after a liquefaction reaction.

As a result of diligent research to solve the above-mentioned problems, the present inventors have pretreated cellulosic biomass with a solid acid, and then hydrothermally decomposed it at an appropriate temperature, thereby converting the cellulosic biomass to a high conversion rate. And found that it can be liquefied into monosaccharides such as glucose and xylose and other liquid compounds, and the present invention has been completed.

The present invention is composed of the following technical matters. That is,
(1) A method for liquefying a cellulose-based biomass, comprising a step of reacting a cellulose-based biomass material with a functional group on the surface of a carrier and hydrothermally decomposing the cellulose-based biomass material.
(2) a first step in which at least a cellulosic biomass material is reacted with a functional group on the surface of the carrier, and the cellulosic biomass material is hydrothermally decomposed;
Separating the solution containing the monosaccharides produced in the first step and the unreacted cellulosic biomass raw material, and hydrothermally decomposing the unreacted cellulosic biomass raw material, A method for liquefying cellulosic biomass.
(3) The first step includes
The temperature for hydrothermal decomposition is set to 50 ° C to 300 ° C,
Producing a liquefied product containing monosaccharide xylose;
Then, the temperature which hydrothermally decomposes | disassembles is set to 50 to 300 degreeC, The process which produces | generates the liquefied substance containing monosaccharide glucose is included, The liquefaction method of the cellulose biomass as described in (2) characterized by the above-mentioned. .
(4) The cellulose-based biomass liquefaction method according to (2), wherein the functional group on the surface of the carrier has a property of receiving an electron pair.
(5) The cellulosic biomass liquefaction method according to (2), wherein the functional group of the surface carrier is an acidic group.
(6) The method for liquefying cellulosic biomass according to (2), wherein the acid amount of the surface support is 0.5 (mmol / gram) to 5.0 (mmol / gram).
(7) The cellulose-based biomass liquefaction method according to (2), wherein the carrier is a thermoplastic resin and / or an inorganic solid.
(8) The method for liquefying a cellulose-based biomass according to (7), wherein the inorganic solid is at least one selected from alumina, silica, zirconia, titania, zeolite, and activated carbon.
(9) The method for liquefying a cellulose-based biomass according to (7), wherein the thermoplastic resin is polystyrene.
(10) a processing means for pulverizing cellulosic biomass;
A first process comprising: a preparation unit that uses the pulverized cellulosic biomass as a cellulosic biomass material by the processing unit; and a cellulosic biomass material supply unit that supplies the cellulosic biomass material to a carrier having a functional group. And
The first processing unit includes a means for separating a solution containing the monosaccharide to be generated and an unreacted cellulosic biomass material, and a second processing unit for hydrothermally decomposing the unreacted cellulosic biomass material. It is the technique regarding the liquefying apparatus of the cellulose biomass characterized by this.

According to the present invention, cellulosic biomass can be easily and easily converted to monosaccharides and other liquid compounds at a high conversion rate. Further, according to the present invention, various cellulosic biomass can be liquefied into monosaccharides and other liquid compounds at a high conversion rate, and the product monosaccharides and solid acids are easily separated, In addition, a method for liquefying cellulose-based biomass that facilitates recovery of a reaction solution and the like is provided. In particular, in the present invention, biomass can be converted into monosaccharides and other liquid compounds by treatment with only a solid acid and / or a solid base catalyst without enzyme treatment.

Hereinafter, embodiments of the present invention will be described in detail.

The method for liquefying cellulosic biomass of the present invention comprises a step of reacting with a functional group on the surface of a carrier and hydrothermally decomposing the cellulosic biomass raw material. Moreover, the method for liquefying a cellulose-based biomass of the present invention includes a first step of hydrolyzing a cellulose-based biomass raw material with a functional group on the surface of a carrier to hydrolyze it into a monosaccharide; It has the 2nd process made into a monosaccharide and another liquid compound by hydrothermally decomposing the unreacted cellulosic biomass raw material which was not decomposed | disassembled in the process.

In the first step, the cellulosic biomass is biomass containing the polysaccharide cellulose constituting the plant wall, and generally refers to residues of trees, grasses, or agricultural products. Others include building waste, thinned wood, straw and bagasse (squeezed sugar cane), corn stalks and leaves. The cellulosic biomass is mainly composed of cellulose, hemicellulose, and lignin. Cellulose is a polysaccharide obtained by dehydration condensation of glucose, which is a typical monosaccharide, and hemicellulose is a complex polysaccharide obtained by dehydration condensation of glucose, xylose, mannose and the like. In addition, since lignin is hard to decompose | disassemble with a phenolic compound, it is said that it is difficult to utilize as a biomass raw material.

In the present invention, the cellulosic biomass is subjected to the necessary treatment to obtain a cellulosic biomass raw material. Here, the necessary treatment is a treatment for reacting the functional group on the surface of the carrier in the first step. Specifically, the cellulose-based biomass is washed, dried, and further promotes the hydrolysis reaction. Crushing and the like. For example, natural cellulosic biomass is washed with water, then dried by an absolute drying method or the like, and pulverized to a predetermined size using a commercially available mill pulverizer. After performing the necessary treatment in this way, the cellulosic biomass becomes a cellulosic biomass material having a predetermined size. The particle size of biomass as a biomass raw material is 2 mm or less, and preferably 20 mesh to 10 mesh. If it is less than 20 mesh, energy consumption increases and pretreatment costs increase, which is not preferable. On the other hand, if it exceeds 2 mm, a sufficient hydrothermal decomposition reaction does not occur, which is not preferable. Next, the cellulosic biomass washed, dried and pulverized is used as an aqueous solution, and used as the cellulosic biomass raw material of the present invention.

Next, in a 1st process, the said cellulose biomass raw material is made to react with the functional group of a support | carrier surface, and hydrothermal decomposition is performed. The substance that can be used as the carrier is not particularly limited as long as it is capable of immobilizing and supporting a functional group and is acidic or basic. Further, the carrier itself may have a predetermined functional group on its surface structure. For example, a cation exchange resin in which an acid is fixed on the surface of a polystyrene carrier which is a thermoplastic resin, or silica, alumina, zirconia, titania, zeolite, activated carbon or the like having an acidic group or a hydroxyl group in its surface structure Furthermore, the mixture which consists of 2 or more types of combinations to these can be illustrated. By adjusting the kind of cation exchange resin and the calcination temperature of silica or alumina carrier, the acidity or basicity can be changed by adjusting the acid group or basic group present on the surface appropriately. . Thus, in the present invention, a support having a functional group on the support surface is called a solid catalyst.

The functional group on the surface of the carrier is not particularly limited as long as it can react with the cellulosic biomass raw material to form a liquid compound such as a monosaccharide, and depends on the type of cellulosic biomass. Can be appropriately selected. For example, a functional group having a Lewis acid having a property of receiving a Bronsted acid such as a strongly acidic sulfonic acid group or a hydrogen ion or an electron pair can be exemplified.

On the other hand, when the biomass constituting the cellulosic biomass is, for example, woody biomass such as red pine waste, a carrier having a hydroxyl group may be used to dissolve the lignin component constituting the surface of the red pine waste. it can. For example, as a functional group, a functional group having a Lewis base having a property of providing a compound or an electron pair, such as magnesium oxide or magnesium hydroxide, which is a carrier having a hydroxyl group, can be adopted. Thus, in the first step of the present invention, the cellulosic biomass can be made into a monosaccharide by hydrothermally decomposing the cellulosic bimus raw material and the functional group on the surface of the carrier. The hydrothermal decomposition reaction proceeds by a normal ester hydrolysis reaction, and the cellulosic biomass raw material becomes monosaccharides such as glycol, fructose, xylose, mannose, and other liquid compounds.

In the second step, the unreacted cellulosic biomass raw material that has not been converted into monosaccharides or other liquid compounds by hydrothermal decomposition reaction in the first step is converted to monosaccharides or other liquid compounds by hydrothermal decomposition. It is a process to do. Thus, in the present invention, the cellulosic biomass is completely decomposed into monosaccharides and other liquid compounds by having at least two steps of hydrothermal decomposition by reaction with the functional group on the surface of the carrier. It is.

The solid acid catalyst used in the first step may be one kind of the solid acid catalyst or two or more kinds as necessary. These solid acid catalysts can be used by being packed in a column, or can be used in direct contact with the cellulosic biomaterial. In the first step, the temperature at which the solid acid catalyst reacts with the cellulosic biomass raw material can be appropriately set according to the melting point of the carrier used as the durable temperature of the solid acid catalyst, Preferably, it is 70 to 250 ° C. Specifically, the reaction temperature is a limit temperature whose upper limit is the melting point of the carrier. For example, when polystyrene is used as a carrier, the reaction temperature can be set to 70 ° C. to 150 ° C. When silica is used as a carrier, the reaction temperature can be set to 70 ° C to 300 ° C. When alumina is used as a support, the reaction temperature can be set to 70 ° C to 300 ° C.

Moreover, in a 1st process, only a required monosaccharide can be manufactured by setting suitably the reaction temperature of a cellulosic biomass raw material and a solid acid catalyst in the said range. For example, when it is desired to produce only xylose (C5) contained in the cellulosic biomass material, the reaction temperature in the first step can be set to 70 ° C. to 180 ° C. Moreover, when it is desired to produce only glucose (C6) contained in the cellulosic biomass raw material, the reaction temperature in the first step can be set to 70 ° C. to 250 ° C. Thus, in this invention, the reaction temperature in a 1st process can be set suitably, and the ratio of the various monosaccharides which occupy for the whole liquids, such as a monosaccharide and a liquefied compound, can be determined. For example, when the ratio of xylose (C5) in the entire liquid is to be increased, the set temperature in the first step is set to 120 ° C. to 150 ° C., and the hydrothermal decomposition temperature in the second step described later is set to 150 ° C. What is necessary is just to set it as 1 to 180 degreeC.

In the first step, the reaction time is preferably 1 minute to 24 hours. The reaction time is preferably 10 minutes to 12 hours. When the treatment time is less than 1 minute, sufficient hydrothermal decomposition reaction does not proceed, and when it exceeds 24 hours, the decomposition of the produced monosaccharide further proceeds and the operation time becomes longer. From the viewpoint of From another point of view, in the present invention, a program in which the hydrothermal decomposition temperature and decomposition time are set is prepared, and a liquefaction reaction is performed based on the program to produce a liquid composed of a monosaccharide and a liquid compound having a desired concentration. Is something that can be done.

In the second step, after producing monosaccharides such as xylose from the cellulosic biomass resources in the first step, the unreacted cellulose biomass raw material remaining in the reaction system is hydrothermally decomposed to produce monosaccharides such as glucose or the like. This is a process for making other liquid compounds. As described above, in the present invention, by combining the first step and the second step, the cellulose-based biomass raw material is converted into a monosaccharide in the first step, and the unreacted raw material in the first step in the second step. Can be converted into a monosaccharide or other liquid compound, and the cellulose-based biomass raw material can be almost completely converted into a liquid compound by each step.

In the second step, liquid compounds other than monosaccharides can be produced by adjusting the hydrothermal decomposition time and hydrothermal decomposition temperature in the same manner as in the first step. The hydrothermal decomposition temperature is preferably 120 ° C to 180 ° C. The hydrothermal decomposition time is preferably 0.5 hours to 24 hours.

In the second step of the present invention, the generated liquid compound is a low molecular weight compound other than a monosaccharide, such as formic acid, acetic acid, glycolic acid, levulinic acid, gluconic acid, or ethanol, xylitol, sorbitol, etc. Was clarified by detailed qualitative analysis of liquid chromatography and gas chromatography-mass meter (GC-MASS: Shimadzu GC-17A-QP5050).

Hereinafter, although the present invention is explained using an example, the present invention is not limited to these at all.

<Strongly acidic ion exchange resin>
As an example of the solid acid catalyst for hydrothermally decomposing the cellulosic biomass used in the present invention, the following cation exchange resin was employed. For example, Amberlist 15 Dry (manufactured by Rohm and Haas), Amberlist 31 Wet (manufactured by Rohm and Haas), Amberlist 15 Wet (manufactured by Rohm and Haas), Diaion PK228 (Mitsubishi Chemical) Made by Co., Ltd.).

<Sulfonic acid-carbon solid acid: CSA-1>
A sulfonic acid-carbon solid acid catalyst, which is a solid acid catalyst for hydrothermally decomposing cellulosic biomass used in the present invention, was prepared as follows. First, 20 g of special grade naphthalene (Kishida Chemical Co., Ltd.) and 200 ml of concentrated sulfuric acid (Tokyo Chemical Industry Co., Ltd.) having a weight percent concentration of 96% or more were heated at 250 ° C. for 15 hours in a nitrogen atmosphere. Next, excess concentrated sulfuric acid was subjected to vacuum distillation at 250 ° C. for 5 hours to remove sulfuric acid and dark brown tar, and a black solid was obtained in the flask. Next, the obtained black solid is finely crushed into a powder form. And it wash | cleans repeatedly until a sulfate radical ion is no longer detected with boiling water. Thereafter, the obtained solid was dried to prepare a sulfonic acid-carbon solid acid CSA-1 using naphthalene as a starting material.

<Sulfonic acid-mesoporous silica solid acid catalyst: MPS-1>
The sulfonic acid-mesoporous silica solid acid catalyst MPS-1 used in the present invention was prepared as follows. First, 129 g of 1.9 M hydrochloric acid was added to 4.0 g of the resin (P123), stirred and dissolved, 32.8 mmol of tetraethylsilylate (TEOS) was added, and the mixture was stirred for 3.0 hours. Next, 8.2 mmol of 3-mercaptopropyltrimethoxysilane (MPTMS) was added and stirred for about 30 minutes. Then, 73.8 mmol of hydrogen peroxide was added, and the mixture was stirred for 20 hours at 40 ° C., and a white precipitate was formed. The precipitate was subjected to stationary aging at 100 ° C. for 24 hours to grow crystals. After filtration, the precipitate was dried in air overnight. This filtrate was extracted with ethanol using Soxhlet to remove the surfactant. Finally, the filtrate was washed with ethanol and water and dried under vacuum conditions at 60 ° C. to prepare an MPS-1 solid acid catalyst into which a sulfonic acid group was introduced.

<Sulfonic acid-mesoporous silica solid acid catalyst: MPS-2>
A sulfonic acid-mesoporous silica solid acid catalyst (MPS-2) used in the present invention was prepared as follows. First, 129 g of 1.9 M hydrochloric acid was added to 4.0 g resin (P123), and the mixture was stirred and dissolved. 7.69 g of tetraethylsilylate (TEOS) was added, and 3-mercaptopropyltrimethoxysilane (MPTMS) was added in an amount of 0.001. 81g was added and it stirred at 40 degreeC for 20 hours. Next, aging was carried out by standing at 100 ° C. for 24 hours to grow crystals. After filtration, the precipitate was dried in air overnight. This filtrate was extracted with ethanol using Soxhlet to remove the surfactant. The extracted solid was subjected to an oxidation treatment using 30 wt% aqueous hydrogen peroxide in a room temperature argon gas atmosphere. Next, each was washed with ethanol and water, and a 1.0 M sulfuric acid solution was added so as to be 1.0 wt%, followed by immersion for 1.0 hour. Finally, each was again washed with ethanol and water and dried under vacuum conditions at 60 ° C. to prepare a sulfonic acid-mesoporous silica solid acid catalyst (MPS-2) into which a sulfonic acid group was introduced.

<Sulfonic acid-hybrid mesoporous silica solid acid catalyst: HMPS-1 / SO ₃ H-HMM>
The sulfonic acid-hybrid mesoporous silica solid acid catalyst (HMPS-1) used in the present invention was prepared as follows. First, 7.93 g octadecyltrimethylammonium chloride (ODTMA) was added to a mixed solution of 3M sodium hydroxide (35.48 g) and ion-exchanged water (224 ml), stirred and dissolved, and 11.0 g 1,2-bistri Ethoxysilylethane (BTEE) and 2.07 g 3-mercaptopropyltrimethoxysilane (MPTMS) were added and stirred at room temperature for 20 hours. Next, aging was carried out by standing at 100 ° C. for 24 hours to grow crystals. After filtration, the precipitate was dried in air overnight. This filtrate was stirred and refluxed for 12 hours at 70 ° C. in an ethanol solution (200 ml) containing 36% hydrochloric acid (3.0 g) to remove the surfactant. In order to oxidize the thiol group on the surface of this solid (1.0 g), oxidation treatment was performed using 65 wt% concentrated nitric acid (10 g) at room temperature for 24 hours. The filtered powder was washed with a large amount of hot water, dried under vacuum, and a sulfonic acid-hybrid mesoporous silica solid acid catalyst (HMPS-1) into which a sulfonic acid group was introduced was prepared.

(Example 1)
As cellulosic biomass, reed pulp (collected from fallow fields in Harumi-cho, Fuchu-shi, Tokyo, treated with delignification, composition: whole cellulose 91.4%, hemicellulose 0.5%, acid-insoluble lignin 7.1%, acid-soluble lignin 1.0%) was used as a raw material, and the biomass was monosaccharided by solid acid hydrothermal decomposition. Solid acid hydrothermal decomposition was performed as follows. First, the reed pulp was pulverized with a commercial mill pulverizer: Wonder Blender (WB-1 Osaka Chemical Co., Ltd.), and then dried by an absolutely dry method. The pulverized and dried reed pulp was prepared with a particle size of about 14 mesh under. 1.0 g of the above-pulverized and dried reed pulp was dissolved in 50 ml of distilled water to prepare an aqueous solution containing reed pulp.

As a solid acid, Amberlyst 15 Dry (manufactured by Rohm and Haas Co., Ltd.), which is the above strongly acidic ion exchange resin, was adopted and subjected to a hydrolysis reaction. The physical properties of Amberlyst 15 Dry (manufactured by Rohm and Haas Co., Ltd.) are as follows: acid amount: 4.48 [mmol / gram], particle size: about 18 mesh or less. As a reaction apparatus, 50 ml of an aqueous solution containing reed pulp particles was placed in a sealable tube-type reaction tube with a 25φ stainless steel tube attached with a swedient log cap, and the solid acid catalyst and water were placed therein. Thereafter, hydrothermal decomposition reaction was performed at 120 ° C. for 24 hours, and biomass saccharification and liquefaction were completed only in the first step.

In the present example, the reaction product obtained by hydrothermally decomposing the biomass of reed pulp by the reaction only in the first step was filtered through a 0.2 μm membrane filter (product name: TO20A047A, manufactured by Advantex). The residue was separated into a water-soluble part. From the weight of the raw material first input and the weight of the residue collected after solid hydrothermal decomposition, it was calculated as the biomass liquefaction rate (Total Conversion). Glucose (C6) and xylose (C5), which are monosaccharides produced in the water-soluble part, were subjected to qualitative and quantitative analysis by liquid chromatography as follows. The conversion rate to monosaccharide glucose (C6) and the conversion rate to monosaccharide xylose (C5) are shown as sugar yield. Furthermore, the conversion to the monosaccharide glucose (C6) and the sum of the monosaccharide xylose (C5) were calculated as the total monosaccharide yield (Saccharo-yield [%]).

High-performance liquid chromatography (HPLC, Amide80 column (Tosoh Co., Ltd., refractive index RI detector) manufactured by Tosoh Corporation) and high-performance liquid chromatography (HPLC, column manufactured by Shimadzu Corporation) as measuring instruments used for the above qualitative and quantitative analysis : TSKgel OApak-A (Tosoh Co., Ltd., conductivity detector) The analysis conditions were carrier liquid flow rate: 1.0 ml / min, column temperature: 80 ° C., carrier: 80/20 vol%, acetonitrile / Water and carrier liquid flow rate: 0.7 ml / min, column temperature: 40 ° C., carrier: 0.75 mM sulfuric acid, and below, the solid acid hydrothermal decomposition temperature and the monosaccharide glucose ( Conversion to C6) (■) and conversion to monosaccharide xylose (C5) (●), conversion to monosaccharide glucose (C6) and monosaccharide xylose (C5) Total monosaccharide yield (Saccharo-yield) (▲), and the total liquefaction rate of biomass (Total Conversion [%] calculated from the weight of the raw material first charged and the weight of the residue recovered after solid hydrothermal decomposition. ]) (♦).

(Example 2 and Example 3)
Cellulosic biomass was saccharified and liquefied in the same manner as in Example 1 except that the temperature of the hydrothermal decomposition reaction was changed to 150 ° C. (Example 2) and 180 ° C. (Example 3), respectively. Similarly, in FIG. 1, the solid acid hydrothermal decomposition time, the conversion rate from biomass to monosaccharide glucose (C6) (■), and the conversion rate to monosaccharide xylose (C5) (●) are shown as sugar yield ( %) (Solid line). Further, the total monosaccharide yield (Saccharo-yield) (▲) and the total liquefaction rate of biomass (Total Conversion [%]) (♦) are shown (solid line).

(Comparative Examples 1 to 3)
Except not using a solid acid, the saccharification and liquefaction of the biomass (reed pulp) were performed in the same manner as in Examples 1 to 3, respectively. The results are shown in FIG.

As a result, in the experiment in which Solid Acid Amberlyst 15 Dry (Rohm and Haas Co., Ltd.) was added, the yield of total sugar produced decreased as the reaction temperature increased. However, looking at the breakdown, the yield of monosaccharide xylose (C5) sugar was highest in the reaction at 120 ° C., and decreased to a level where it was hardly detected at 150 ° C. and 180 ° C. On the other hand, monosaccharide glucose (C6) sugar decreased at 180 ° C. with a peak at 150 ° C. This phenomenon has a lower yield than the catalyst in each conversion rate, but the same tendency was applied to the blank experiment without catalyst. That is, it is suggested that the decomposition behaviors of the monosaccharide xylose (C5) sugar and the monosaccharide glucose (C6) sugar are different, and the monosaccharide xylose (C5) is considered to be more easily decomposed. In the reaction at 180 ° C. for 24 hours, although the total biomass liquefaction rate was increased, the amount produced as monosaccharide was small. This is considered to have been converted to liquid substances other than monosaccharides such as formic acid, acetic acid, glycolic acid, levulinic acid, gluconic acid, etc. under severe conditions where the hydrothermal decomposition temperature is 150 ° C. or higher.

(Examples 4 to 6)
Example 1 except that the hydrothermal decomposition temperature was set to 150 ° C. and the hydrothermal decomposition times were 3 hours (Example 4), 12 hours (Example 5) and 24 hours (Example 6), respectively. In the same manner, saccharification and liquefaction of reed pulp were performed. The results are shown in FIG. As in FIG. 1, the solid acid hydrothermal decomposition time, the conversion rate from biomass to monosaccharide glucose (C6) (■), and the conversion rate to monosaccharide xylose (C5) (●) are shown. Furthermore, the conversion rate to the monosaccharide glucose (C6) (■), the total monosaccharide yield (Saccharo-yield [%]) of the monosaccharide xylose (C5) (▲), the total liquefaction rate of biomass (Total) Conversion [%]) (♦).

From the above examples, even in the reaction in the presence of a catalyst at 150 ° C., the yield of the monosaccharide xylose (C5) was high at the beginning as with the influence of the reaction temperature, and the result decreased with time. On the contrary, monosaccharide glucose (C6) increased with time.

(Examples 7 to 11)
The solid acid catalyst MPS-1 was used as the solid catalyst, the temperature of the hydrothermal decomposition reaction was set to 170 ° C., and the hydrothermal decomposition time was 1 hour (Example 7), 3 hours (Example 8), The saccharification and liquefaction of reed pulp were performed in the same manner as in Example 1 except that the time was 6 hours (Example 9), 12 hours (Example 10), and 24 hours (Example 11). The results are shown in FIG.

As a result, the peak of total sugar yield was shifted up to 12 hours. And the conversion rate reduction of monosaccharide xylose (C5) also became rapid.

(Examples 12 to 18)
The hydrothermal decomposition temperature was set to 180 ° C., and the hydrothermal decomposition time was 30 minutes (Example 12), 1 hour (Example 13), 3 hours (Example 14), 4 hours (Example 15), The saccharification and liquefaction of reed pulp were performed in the same manner as in Example 7 except that the time was 6 hours (Example 16), 12 hours (Example 17), and 24 hours (Example 18).

As a result, the peak conversion rate shifted up to 3 hours. And the conversion reduction of monosaccharide xylose (C5) also became rapid simultaneously.

(Comparative Examples 4 to 6)
The saccharification and liquefaction of reed pulp were performed in the same manner as in Example 13, Example 15, and Example 17 except that no solid acid was used. The hydrothermal decomposition times were 1 hour (Comparative Example 4), 3 hours (Comparative Example 5) and 6 hours (Comparative Example 6), respectively.

Furthermore, the result of putting together the data of Example 12 thru | or Example 18 and Comparative Example 4 thru | or Comparative Example 6 is shown in FIG. From FIG. 5, it was found that the yield of monosaccharides of biomass increases by adding a solid acid catalyst. In addition, the total liquefaction rate of the raw material is greatly increased by the acid catalyst. From these facts, it became clear that the effect of adding a solid acid catalyst was observed in the hydrothermal decomposition reaction.

Based on the data of Examples 7 to 11 in which the hydrothermal decomposition temperature was set to 170 ° C. and Examples 12 to 18 in which the hydrothermal decomposition temperature was set to 180 ° C., the mesoporous silica solid acid catalyst MPS-1 The results of the reaction time, the total monosaccharide yield, and the total liquefaction rate at each of the above temperatures were summarized. The results are shown in FIGS.

(Example 19 to Example 21)
CSA-1 was used as the solid catalyst, the hydrothermal decomposition temperatures were set to 120 ° C., 150 ° C., and 180 ° C., respectively, and the hydrothermal decomposition times were 24 hours (Examples 19 to 20) and 3 hours, respectively. Except for the (Example 21), saccharification and liquefaction of reed pulp were performed in the same manner as in Example 1. The results are shown in FIG.

As is clear from the above examples, it is understood that both the sugar yield and the total conversion increase with the increase of the hydrothermal decomposition temperature. When the hydrothermal decomposition temperature was 180 ° C., the reaction time was shorter than others, but the production of monosaccharides was most promoted. From these results, when priority is given to the conversion reaction to the monosaccharide xylose (C5), the hydrothermal decomposition temperature is preferably set to 170 ° C. to 180 ° C., and the decomposition time is preferably set to less than 1 hour. On the other hand, when priority was given to conversion to monosaccharide glucose (C6), it was found that setting at 180 ° C. for 3 hours or 170 ° C. for 12 hours was preferable.

(Examples 22 to 27)
As solid catalysts, CSA-1, MPS-1, MPS-2, HMS-1, Amberlyst 15 Dry, Amberlyst 31 Wet were used, the hydrothermal decomposition temperature was set to 150 ° C., and the hydrothermal decomposition time was 24. Except for the time, saccharification and liquefaction of reed pulp were performed in the same manner as in Example 1. The results are shown in FIG.

From FIG. 9, the solid acid catalyst in which the monosaccharide xylose (C5) sugar was most converted was the HMS-1 solid acid catalyst. And it was a CSA-1 solid acid catalyst that the yield of monosaccharide glucose (C6) was high. The total monosaccharide yield with this catalyst was about 17%, and the total liquefaction rate of the raw materials was about 50%.

(Examples 28 to 31)
Example 28 (CSA-1), Example 29 (MPS-1), except that the hydrothermal decomposition temperature was set to 180 ° C. and the hydrothermal decomposition time was 3 hours. The solid catalyst of Example 30 (MPS-2) and Example 31 (HMS-1) was used.), And the reed pulp was saccharified and liquefied. The results are shown in FIG.

(Comparative Example 7)
Saccharid pulp was saccharified and liquefied in the same manner as in Example 28 except that no solid acid was used.

From FIG. 10, the solid acid catalyst in which the monosaccharide xylose (C5) sugar was most converted was an HMS-1 solid acid catalyst as in the result at 150 ° C. On the other hand, the yield of monosaccharide glucose (C6) was high in the MPS-1 solid acid catalyst. The total sugar yield with this catalyst was about 22%, and the total liquefaction rate of the raw materials was about 83%. Moreover, it turns out that the effect of a catalyst is remarkable also in the sugar yield and the total liquefaction rate compared with the comparative example 7 which does not use a solid acid.

From the above single-step examples, monosaccharide xylose (C5) and monosaccharide glucose (C6) each have an optimum hydrothermal decomposition temperature and hydrothermal decomposition time for making a monosaccharide. There was found. Therefore, the saccharification and liquefaction reaction of cellulosic biomass is divided into two steps (or two steps) or more steps (multisteps), and monosaccharide xylose (C5), monosaccharide glucose (C6), and others The selective production of liquid compounds was studied.

(Example 32)
<Two-stage solid acid hydrothermal decomposition>
In order to selectively obtain monosaccharide xylose (C5) using MPS-1 as a solid acid catalyst, using a small autoclave with stirring instead of a tube reactor, and at a temperature of 180 ° C. for 10 minutes. And the monosaccharide xylose (C5) was recovered and the unreacted biomass was hydrothermally decomposed at 180 ° C. for 3 hours as the second step in the same manner as in Example 1. Then, saccharification and liquefaction of reed pulp were performed. The results are shown in Table 1.

From Table 1, the monosaccharide produced in the first step is mostly monosaccharide xylose (C5), the monosaccharide yield is 11.1%, and the monosaccharide produced in the second step is mainly monosaccharide glucose (C6 ), The monosaccharide yield was 13.3%, the total sugar yield was 24.4%, and the final liquefaction rate of reed pulp was 77.2%. That is, the required monosaccharide can be obtained by appropriately setting the hydrothermal decomposition temperature and time.

(Example 33)
<Two-stage or multi-stage solid acid hydrothermal decomposition>
The saccharification and liquefaction of reed pulp were performed in the same manner as in Example 32 except that CSA-1 was used as the solid acid catalyst. The results are shown in Table 1. From Table 1, similar results were obtained, and the monosaccharide yield obtained by adding the monosaccharides produced in the first step and the monosaccharides produced in the second step was 26.1%.

After hydrothermal decomposition in the second step, hydrothermal decomposition was further carried out at 150 ° C. for a total of 16 hours. This was attempted for the purpose of converting and decomposing those that were dissolved in the solution but could not be reduced to a monosaccharide. The results are shown in Table 1. The monosaccharide yield slightly increased by adding 150 ° C. operation for 3 hours, but no significant change was observed.

(Example 34 to Example 35)
Saccharified and liquefied reed pulp were carried out in the same manner as in Example 32 except for the hydrothermal decomposition temperature set as shown in Table 2 and the reaction time. The results are shown in Table 2.

Looking at Table 2, in Example 34, even if the monosaccharide was not recovered from the solution after the reaction in the first step at 180 ° C. for 10 minutes, the operation at 150 ° C. in the third step and the fourth step, There was no significant improvement in the recovery efficiency of monosaccharide glucose (C6). Further, in Example 35, the hydrothermal decomposition temperature in the first step was lowered from 180 ° C. to 170 ° C., and in the second step, the reaction conditions were shortened from 3 hours to 1 hour in 180 ° C., and the reaction conditions were made milder. Conversion to monosaccharide glucose (C6) is not promoted even by hydrothermal decomposition, and the concentration of monosaccharide xylose (C5) produced under mild conditions compared to monosaccharide glucose (C6) is 12.6% in the second step. In the third step, it increased to 13.3%.

From these facts, when sugar is generated by solid acid hydrothermal decomposition reaction, disaccharides and polysaccharides are not generated, but they are selectively reacted from β-1,4 glycosidic bond at the end of cellulose chain. Can be guessed.

(Example 36)
<Reuse of solid acid catalyst>
The solid acid catalyst CSA-1 used in Example 21 was recovered, and this catalyst was used to saccharify and liquefy the reed pulp in the same manner as in Example 21. The solid acid catalyst was recovered and used up to 5 times. The total conversion to monosaccharide xylose (C5) and monosaccharide glucose (C6) produced in each use was calculated as the total monosaccharide yield (Saccharo-yield [%]). The results are shown in FIG.

As shown in FIG. 11, it was found that the solid acid catalyst CSA-1 maintains the initial activity (monosaccharide yield) up to three repeated experiments (run 3). In addition, in the fourth to fifth repeated reactions, the yield of the whole monosaccharide was decreased by about 20 to 28%, but an increase in the production amount of the product monosaccharide xylose (C5) was observed. From the result that the monosaccharide xylose (C5) proceeds in a milder reaction state, it is considered that the acid amount of the catalyst decreases as it is used for repeated use experiments. Although there was a slight decrease in activity, it was found that it could be used several times with a solid acid catalyst.

(Reference Example 1)
<Measurement of acid amount of solid acid catalyst>
The acid amounts of various solid acid catalysts used in this example were measured. The number of hydrogen ions per unit mass (H ⁺ mmol / g) was defined as the acid amount. The acid amount of the solid acid catalyst was measured by the following acid-base titration method. A 2M sodium chloride solution and a 0.1M sodium hydroxide solution were used, and the procedure was as follows. First, 0.1 gram of the various solid acid catalysts to be measured was added to 20 gram of 2M sodium chloride solution. Next, the solution mixed with the solid acid catalyst was stirred at room temperature for 24 hours. Finally, a titration curve was prepared by titrating a 0.1 sodium hydroxide solution, and the acid amount (H ⁺ mmol / g) per 1.0 g of the solid acid catalyst was calculated from the titration amount. The results are shown in Table 3.

According to Table 3, except for the ion exchange resins (15DRY and 31Wet),
The amount of acid was in the order of CSA-1>MPS-1>MPS-2> HMPS-1. This order became the same as the result of the activity test of the solid acid type of the example and the activity and order of the sugar conversion rate. That is, it was confirmed that H ^+, which is the acid amount of the solid acid catalyst, promotes swelling, low molecular weight, and sugar conversion of biomass.

The liquefaction method of cellulosic biomass of the present invention can greatly contribute to technological innovation in the field of energy development, the field of organic synthetic chemistry represented by ethanol production, and the field of environmental technology.

It is the figure which showed the hydrothermal decomposition temperature, the conversion rate of monosaccharide glucose (C6), and monosaccharide xylose (C5), the sugar yield, and the total liquefaction rate. It is the figure which showed the hydrothermal decomposition temperature, the conversion rate of monosaccharide glucose (C6), and monosaccharide xylose (C5), the sugar yield, and the total liquefaction rate. It is the figure which showed hydrothermal decomposition time, conversion rate of monosaccharide glucose (C6), and monosaccharide xylose (C5), conversion rate, sugar yield, and total liquefaction rate. It is the figure which showed the hydrothermal decomposition time, the conversion rate of monosaccharide glucose (C6) and monosaccharide xylose (C5), the sugar yield, and the total liquefaction rate. It is the figure which showed the hydrothermal decomposition time, the conversion rate of monosaccharide glucose (C6) and monosaccharide xylose (C5), the sugar yield, and the total liquefaction rate. It is the figure which showed hydrothermal decomposition time, conversion rate of monosaccharide glucose (C6) and monosaccharide xylose (C5), and sugar yield. It is the graph which showed the decomposition time in each hydrothermal decomposition temperature, the conversion rate of monosaccharide glucose (C6) and monosaccharide xylose (C5), and sugar yield. It is the graph which showed the conversion of monosaccharide glucose (C6) and monosaccharide xylose (C5) in each hydrothermal decomposition temperature, and sugar yield. It is the figure which showed the change of the conversion rate of monosaccharide glucose (C6) and monosaccharide xylose (C5), sugar yield, and a total liquefaction rate by various solid catalysts. It is the figure which showed the change of the conversion rate of monosaccharide glucose (C6) and monosaccharide xylose (C5), sugar yield, and a total liquefaction rate by various solid catalysts. It is the figure which showed the activity at the time of reusing various solid catalysts.

Claims (10)

A method for liquefying a cellulose-based biomass comprising a step of reacting a cellulose-based biomass material with a functional group on the surface of a carrier and hydrothermally decomposing the cellulose-based biomass material. A first step of reacting at least a cellulosic biomass material with a functional group on the surface of the carrier, and hydrothermally decomposing the cellulosic biomass material;
Separating the solution containing the monosaccharides produced in the first step and the unreacted cellulosic biomass raw material,
A second step of hydrothermally decomposing the unreacted cellulosic biomass material;
A method for liquefying cellulosic biomass, comprising: The first step includes
The temperature for hydrothermal decomposition is set to 50 ° C to 300 ° C,
Producing a liquefied product containing monosaccharide xylose;
Then, the temperature which hydrothermally decomposes | disassembles is set to 50 to 300 degreeC, The process which produces | generates the liquefied substance containing monosaccharide glucose is included, The liquefaction method of the cellulosic biomass of Claim 2 characterized by the above-mentioned. . The method for liquefying cellulosic biomass according to claim 2, wherein the functional group on the surface of the carrier has a property of receiving an electron pair. The method for liquefying cellulosic biomass according to claim 2, wherein the functional group of the surface carrier is an acidic group. The method for liquefying cellulosic biomass according to claim 2, wherein the acid amount of the surface support is 0.5 (mmol / gram) to 5.0 (mmol / gram). The method for liquefying cellulosic biomass according to claim 2, wherein the carrier is a thermoplastic resin and / or an inorganic solid. The method for liquefying a cellulose-based biomass according to claim 7, wherein the inorganic solid is at least one selected from alumina, silica, zirconia, titania, zeolite, and activated carbon. The said thermoplastic resin is a polystyrene, The liquefaction method of the cellulose biomass of Claim 7 characterized by the above-mentioned. Processing means for pulverizing cellulosic biomass;
A first process comprising: a preparation unit that uses the pulverized cellulosic biomass as a cellulosic biomass material by the processing unit; and a cellulosic biomass material supply unit that supplies the cellulosic biomass material to a carrier having a functional group. And
The first processing unit includes a means for separating a solution containing the monosaccharide to be generated and an unreacted cellulosic biomass material, and a second processing unit for hydrothermally decomposing the unreacted cellulosic biomass material. An apparatus for liquefying cellulose-based biomass.

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