JP2007091707A - Method and equipment for production of organic acid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the technology for producing CO<SB>x</SB>by using the saccharides largely included in the biomass resource under relatively mild conditions, the technology for selectively producing prescribed organic acid or its alkali salt from saccharides, further the technology for producing organic acid or its alkali salt from the biomass resource other than saccharide. <P>SOLUTION: Saccharide and alkali metal hydroxide are allowed to react with each other at 150°C to 450°C under the anoxic atmosphere to simultaneously produce organic acid or its alkali metal salt and hydrogen. The molar ratio of saccharide to the alkali metal hydroxide is set to 1 mole of the carbon included in the saccharide to 0.5 to 10 moles. Formic acid, acetic acid, glycolic acid, lactic acid, dicarboxylic acid or their alkali metal salts can be selectively produced by controlling the heating temperature and the like. In addition, organic acid or its alkali metal salts also can be obtained when ligrin is used instead of saccharide. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method and apparatus for producing an organic acid or an alkali salt thereof using biomass resources as a raw material, and more specifically, a method and apparatus for simultaneously producing an organic acid or an alkali salt thereof and hydrogen, an organic acid or an acid thereof The present invention relates to a method for selectively producing formic acid, acetic acid, glycolic acid, lactic acid, dicarboxylic acid or alkali salts thereof among alkali salts.

  From the viewpoint of preventing electrode poisoning of a fuel cell, it is necessary to supply hydrogen that does not contain carbon monoxide to a fuel cell, particularly a polymer electrolyte fuel cell (PEFC) that has recently attracted attention. In a conventional hydrogen production process, hydrogen is generated from a fossil fuel such as natural gas, petroleum, or coal by a steam reforming reaction. At this time, most of the carbon contained in the fossil fuel is discharged into the atmosphere as carbon dioxide. However, as a party to the Kyoto Protocol, suppression of emissions of carbon dioxide, a greenhouse gas, is urgent.

  In addition, in the above hydrogen production process, it is impossible to avoid the residual (1 to 3%) of the electrode poisonous substance CO. Therefore, hydrogen depth purification (CO <20 ppm) is unavoidable by a large and high-cost facility using a pressure swing adsorption method (PSA method) or the like. In addition, the steam reforming reaction needs to be heated to a very high temperature of about 800 ° C.

Japanese Patent Application Laid-Open No. 10-25001 describes a method for producing hydrogen by thermochemical decomposition of water and carbon using sodium hydroxide as a reaction medium. Although this method has an advantage that sodium hydroxide can be made to act catalytically by supplying a large excess of carbon to sodium hydroxide, CO and CO ₂ are produced as by-products. There is a problem.

Biomass resources, on the other hand, are finite resources and are reproducible and carbon neutral, unlike fossil fuels that emit large amounts of CO ₂ into the atmosphere. Therefore, many studies are currently being conducted on the effective use of biomass resources. However, most of the woody biomass such as waste wood and newspapers and saccharide biomass such as food residues are disposed of without being effectively used.

As an effective utilization method of biomass resources, for example, US Pat. No. 2,750,414 describes a method of obtaining an organic acid by adding wood to a low concentration sodium hydroxide or sodium carbonate aqueous solution and heating it. . However, this method has a problem that CO and CO ₂ are produced as by-products.
Japanese Patent Laid-Open No. 10-25001 U.S. Pat. No. 2,750,414

In view of the above problems, the present invention uses an organic acid or an alkali salt thereof without producing CO _x (CO and CO ₂ ) under relatively mild conditions using saccharides contained in a large amount of biomass resources. It is an object to provide a method and an apparatus capable of simultaneously producing hydrogen and hydrogen. Moreover, an object of this invention is to provide the manufacturing method of the organic acid or its alkali salt which can selectively produce | generate a predetermined organic acid or its alkali salt using saccharides. Furthermore, it aims at providing the manufacturing method of the organic acid or its alkali salt which can produce | generate an organic acid or its alkali salt also from biomass resources which do not contain saccharides.

  In order to achieve the above object, the present invention reacts a saccharide with an alkali metal hydroxide under a heating condition of 150 to 450 ° C. and in an oxygen-free atmosphere to produce hydrogen and an organic acid or an alkali salt thereof. A method for producing an organic acid or an alkali salt thereof comprising a step of simultaneously producing an alkali metal hydroxide, wherein the molar ratio of the saccharide to the alkali metal hydroxide is 1 mol of carbon contained in the saccharide. Is 0.5 to 10 mol. For example, the reaction when the saccharide is cellulose and the alkali metal hydroxide is NaOH is shown in the following formula 1.

As shown in Formula 1, in a temperature range of 150 to 450 ° C., cellulose is converted into a low molecular weight organic acid (or a sodium salt thereof) such as glycolic acid, formic acid, lactic acid, and acetic acid by reaction with NaOH and water. Decompose. Some of these organic acids react with NaOH and water in the above temperature range, thereby generating hydrogen. In addition, since the carbon atom contained in the organic acid reacts with NaOH to produce Na ₂ CO ₃ , the production of CO and CO ₂ is avoided, and a gas free of CO _x and containing hydrogen with high purity is obtained. Can do. In addition, the gas obtained may contain methane slightly.

  Moreover, this invention is an apparatus which manufactures an organic acid or its alkali salt as another aspect, Comprising: Hydrogen and an organic acid or its alkali salt are produced | generated simultaneously by reaction with saccharide | sugar and an alkali metal hydroxide. The reaction chamber under an oxygen-free atmosphere, the heating means for setting the temperature of the reaction chamber to 150 to 450 ° C., and the alkali metal hydroxide amount to 0.5 to 10 mol with respect to 1 mol of carbon contained in the saccharide. As described above, the quantitative supply means for continuously supplying the saccharide and the alkali metal hydroxide to the reaction chamber, the piping for discharging the hydrogen generated in the reaction chamber, and the organic acid or its alkali from the reaction chamber And a discharging means for continuously taking out the solid residue containing the salt.

Thus, hydrogen can be continuously generated by continuously supplying sugars and alkali metal hydroxide at a constant ratio to the reaction chamber maintained in an oxygen-free atmosphere. The solid residue produced by the reaction contains an alkali salt of an organic acid. Therefore, a certain amount of hydrogen and an alkali salt of an organic acid can be obtained continuously. Further, for example, the organic acid can be separated from the residue by using a solvent that dissolves the alkali salt of the organic acid but does not dissolve the by-product carbonate such as Na ₂ CO ₃ . Therefore, a constant amount of hydrogen and organic acid can be obtained continuously.

  Furthermore, this invention is a manufacturing method of the organic acid or its alkali salt which selectively produces | generates the following organic acids or its alkali salt as another aspect. A method for producing an organic acid or an alkali salt thereof, which selectively produces formic acid or an alkali salt thereof as an organic acid or an alkali salt thereof, under the heating conditions of 0 to 100 ° C., hydroxide or carbonate of cellobiose and alkali metal It is characterized by reacting. A method for producing an organic acid or an alkali salt thereof, which selectively produces acetic acid or an alkali salt thereof as the organic acid or an alkali salt thereof, reacts a saccharide with an alkali metal hydroxide under a heating condition of 250 to 450 ° C. It is characterized by that. A method for producing an organic acid or an alkali salt thereof, which selectively produces glycolic acid or an alkali salt thereof as an organic acid or an alkali salt thereof, comprises a polysaccharide and an alkali metal hydroxide under heating conditions of 220 to 300 ° C. It is made to react. A method for producing an organic acid or an alkali salt thereof that selectively produces lactic acid or an alkali salt thereof as an organic acid or an alkali salt thereof is a monosaccharide and an alkali metal hydroxide or carbonate under heating conditions of 100 to 250 ° C. It is characterized by reacting a salt. A method for producing an organic acid or an alkali salt thereof, which selectively produces a dicarboxylic acid or an alkali salt thereof as an organic acid or an alkali salt thereof, reacts a saccharide with an alkali metal hydroxide under heating conditions of 140 to 380 ° C. It is characterized by making it.

  In this way, the heating temperature is controlled within a predetermined range, and the saccharide and alkali as raw materials are combined in a predetermined combination, so that formic acid, acetic acid, glycolic acid, lactic acid, dicarboxylic acid or those as organic acids or alkali salts thereof are used. The alkali salt can be selectively obtained.

  Furthermore, the present invention provides, as another aspect, an organic acid or an alkali salt thereof which generates an organic acid or an alkali salt thereof by reacting lignin with an alkali metal hydroxide under a heating condition of 140 to 360 ° C. It is a manufacturing method.

  Thus, an organic acid or an alkali salt thereof can also be generated from biomass resources such as lignin not contained in saccharides. In particular, glyceric acid or an alkali salt thereof with high added value can be produced from lignin.

As described above, according to the present invention, an organic acid or an alkali salt thereof and hydrogen are simultaneously produced under relatively mild conditions, using saccharides contained in a large amount of biomass resources, without producing CO _x. Methods and apparatus can be provided. Moreover, according to this invention, the manufacturing method of the organic acid or its alkali salt which produces | generates a predetermined | prescribed organic acid or its alkali salt selectively using saccharides can be provided. Furthermore, according to this invention, the manufacturing method of the organic acid or its alkali salt which produces | generates an organic acid or its alkali salt also from biomass resources which do not contain saccharides can be provided.

Hereinafter, embodiments of the present invention will be described. First, an embodiment of a method for simultaneously producing an organic acid or an alkali salt thereof and hydrogen according to the present invention will be described. In the present embodiment, first, CO _X- free hydrogen is obtained by reacting a saccharide with an alkali metal hydroxide under predetermined heating conditions and in an oxygen-free atmosphere.

  Examples of saccharides that can be used include monosaccharides, disaccharides, oligosaccharides, and polysaccharides. Glucose, fructose, galactose, mannose etc. can be used as monosaccharides, sucrose, maltose, lactose, cellobiose etc. can be used as disaccharides, maltotriose etc. can be used as trisaccharides, starch as polysaccharides, Cellulose, glycogen and the like can be used.

  Moreover, it is preferable to use biomass resources as saccharides. Examples of biomass resources include sucrose biomass such as sugar cane and sugar beet, starch biomass such as rice, wheat, corn, and potato, small diameter trees, thinned wood, sawdust, wood waste, waste paper, rice husk, rice straw, bagasse It is preferable to use cellulosic woody biomass such as natural fiber, newspaper, wrapping paper, tissue paper, toilet paper, and cardboard. Since the present invention can produce organic acids and hydrogen directly from biomass resources, conventionally, woody biomass such as waste wood and newspapers that have been disposed of without being effectively used, and carbohydrates such as food residues Organic acids and hydrogen can be efficiently generated from bioresources such as biomass.

As the alkali metal hydroxide, sodium hydroxide (NaOH), lithium hydroxide (LiOH), potassium hydroxide (KOH), rubidium hydroxide (RbOH) or the like is used, and among these, NaOH is particularly preferable. When NaOH is used, it is used as a raw material for glass or the like by the reaction of the present invention, and sodium carbonate (Na ₂ CO ₃ ) having a higher industrial value than NaOH is generated. Therefore, reaction by-products can also be effectively used.

As the addition amount of the alkali metal hydroxide, it is necessary to add 0.5 mol or more with respect to 1 mol of carbon (C) contained in the saccharide. When the addition amount is less than 0.5 mol, CO and CO ₂ are generated by thermal decomposition of the saccharide. On the other hand, when the addition amount is 0.5 mol or more, carbon (C) in the saccharide forms an alkali metal carbonate, and thus it is possible to prevent the formation of CO _x . Moreover, the production | generation rate of hydrogen and an organic acid can also be improved. In addition, it is preferable that the alkali metal hydroxide is present in a large amount with respect to carbon, but even if it is added in excess of 10 mol, the effect is saturated, so the upper limit of the addition amount is 10 mol. It is preferable to do. A more preferable range of the addition amount is 2 to 5 mol.

  Water vapor can be introduced into the reaction between the saccharide and the alkali metal hydroxide. The amount of water vapor introduced is preferably in the range of 0.5 to 10 mol with respect to 1 mol of carbon (C) contained in the saccharide. By making the introduction amount 0.5 mol or more, it is possible to suppress the production of alkali metal oxides and promote the production of alkali metal carbonates. On the other hand, the amount of heat supplied to the reaction chamber can be suppressed by setting the introduction amount to 10 mol or less. A more preferable range of the introduction amount is in the range of 1 to 4 mol.

The heating condition varies depending on the raw material used, but it is necessary to heat the raw material to at least 150 ° C. or higher. When the heating temperature is less than 150 ° C., hydrogen cannot be generated by decomposing saccharides. On the other hand, the upper limit of the heating temperature must be suppressed to 450 ° C. When heating temperature exceeds 450 degreeC, most of the produced | generated organic acids will decompose | disassemble into hydrogen or methane and carbonate, and an organic acid cannot be obtained. A more preferred upper limit is 350 ° C. For example, the organic acid is glycolic acid (C ₂ H ₄ O ₃ ), formic acid (HCOOH), lactic acid (C ₃ H ₆ O ₃ ), acetic acid (C ₂ H ₄ O ₂ ), and the alkali metal hydroxide is NaOH. In this case, the following expressions 2 to 5 can be expressed.

C ₂ H ₄ O ₃ + 4NaOH → 3H ₂ + 2Na ₂ CO ₃ + H ₂ O (Formula 2)
HCOOH + 2NaOH → H ₂ + Na ₂ CO ₃ + H ₂ O (Formula 3)
C ₃ H ₆ O ₃ + 6NaOH → 6H ₂ + 3Na ₂ CO ₃ (Formula 4)
C ₂ H ₄ O ₂ + 2NaOH → CH ₄ + Na ₂ CO ₃ + H ₂ O (Formula 5)

That is, once the predetermined heating temperature is exceeded, the once generated organic acid disappears, so the overall chemical formula is, for example, saccharide as cellulose (represented by C ₆ H ₁₀ O ₅ which is a unit structure), and alkali metal. When the hydroxide is NaOH, the following formula 6 is obtained.

C ₆ H ₁₀ O ₅ + 12NaOH + H ₂ O → 12H ₂ + 6Na ₂ CO ₃ (Formula 6)

  In addition, after heating saccharides and an alkali metal hydroxide to a predetermined temperature, the temperature may be maintained for a certain period of time to generate an organic acid. However, after heating to a predetermined temperature, rapid cooling is performed. However, the above reaction produces a sufficient amount of organic acid. In the former case, the organic acid can be produced in a batch manner. The heating temperature in this case is preferably 150 to 350 ° C. for cellulose. In the latter case, the organic acid can be continuously produced. The heating temperature in this case is preferably 200 to 450 ° C. for cellulose, for example.

  In addition, this reaction is preferably performed in an oxygen-free atmosphere, for example, in a steam, inert gas, or a mixed gas atmosphere of steam and inert gas in order to prevent saccharides from burning. As the inert gas, a group 0 element gas such as argon (Ar) or nitrogen gas is preferably used. 1-100 volume% is preferable and, as for content of the water vapor | steam in mixed gas, 50-100 volume% is more preferable. Moreover, the produced | generated hydrogen can be removed out of a reaction system by distribute | circulating an inert gas.

  The saccharide and alkali metal hydroxide are not particularly limited as long as they are mixed so that the reaction occurs, but the saccharide is preferably formed in various shapes so as to promote the reaction. For example, it is preferable to use powder, granule, pellet, flake, chip, piece, or porous. Further, depending on the type of saccharide, it may be liquid or slurry. The alkali metal hydroxide is preferably supported on the saccharide as an aqueous solution having a concentration of 10 to 99% by weight.

In the present embodiment, the organic acid is then separated from the solid residue produced by the above reaction. Organic acids produced by this reaction include the above-mentioned glycolic acid, formic acid, lactic acid, acetic acid, monocarboxylic acids such as D-glucuronic acid, gluconic acid, glyceric acid, levulinic acid, propionic acid, oxalic acid, maleic acid It is a low molecular weight organic acid such as dicarboxylic acid such as tartaric acid, malic acid, succinic acid and glutaric acid, and is present in the residue as an alkali salt of organic acid such as sodium salt. In addition to these organic acid salts, the residue contains unreacted saccharides, silica and alkaline earth metal carbonates contained as impurities in the raw materials, and alkali metals such as NaCO ₃ and Na ₂ O as by-products. There are carbonates and oxides. Therefore, it is necessary to separate the organic acid from these by-products.

  As a method for separating the organic acid from the residue, for example, the residue is immersed in an organic solvent such as ethanol, acetone or ether, and the alkali salt of the organic acid is dissolved in the organic solvent. It can be separated from by-products that are insoluble in the solvent. Thereafter, by performing solid-liquid separation such as filtration, solids containing by-products can be removed to obtain a liquid containing an organic acid. In addition, when separating each organic acid, although it changes with kinds of organic acid, it can extract-separate with acid aqueous solutions, such as hydrochloric acid and a sulfuric acid, and an organic solvent, for example.

  Next, an embodiment of an apparatus for simultaneously producing an organic acid and hydrogen according to the present invention will be described. The apparatus according to the present embodiment includes a reaction chamber that simultaneously generates hydrogen and an organic acid or an alkali salt thereof by a reaction between a saccharide and an alkali metal hydroxide, and the temperature of the reaction chamber is set to 150 to 450 ° C. Quantification of continuously supplying saccharide and alkali metal hydroxide to the reaction chamber so that the alkali metal hydroxide is 0.5 to 10 mol per 1 mol of carbon contained in the saccharide with heating means. Supply means, piping for supplying water vapor, inert gas, or a mixed gas thereof to the reaction chamber to maintain the reaction chamber in an oxygen-free atmosphere, piping for discharging hydrogen generated in the reaction chamber, and from the reaction chamber Discharge means for taking out the solid residue and separation means for separating the organic acid from the residue are provided.

  The reaction chamber for carrying out this reaction is a so-called fluidized bed system, and for example, a cylindrical rotary reactor (rotary kiln) or a single-screw or twin-screw extruder can be used. The reaction chamber is preferably made of a material excellent in heat resistance and alkali resistance, such as metals such as stainless steel and aluminum, ceramics such as alumina and zirconia, or heat resistant plastics such as phenol resin and polyphenylene sulfide. Since the presence of the metal catalyst decomposes the organic acid into hydrogen, it is preferable not to add the metal catalyst to the reaction chamber when it is desired to ensure the production amount of the organic acid.

  As a heating means, a heater by resistance heating, a positive temperature coefficient thermistor (PTC heater), a heater using oxidation heat of chemical reaction, a heater by catalytic combustion, a heater by induction heating, hot air is supplied to the outer periphery of the reaction chamber. Thus, an external heating type heating means for indirectly heating the raw material can be used.

  As the quantitative supply means, saccharides and alkali metal hydroxides or aqueous solutions thereof can be weighed and supplied to the reaction chamber by adjusting the supply rate so as to obtain a predetermined molar ratio. There is no particular limitation. These may be mixed and then supplied to the reaction chamber, or may be supplied separately.

  The pipe for supplying water vapor or inert gas into the reaction chamber may be configured to supply a mixed gas of water vapor and inert gas into the reaction chamber, or may be configured to supply them separately. In order to obtain water vapor, a vaporizer or the like can be provided outside the reaction chamber. You may comprise the piping which discharges | emits hydrogen so that it can supply to apparatuses using hydrogen, such as a fuel cell. In addition, the inert gas and unreacted water vapor introduced into the reaction chamber are discharged together with hydrogen from the piping for discharging hydrogen.

  For example, when a rotary kiln is used as the reaction chamber, the discharge means for taking out the solid residue from the reaction chamber can be inclined by tilting the cylindrical shaft, thereby rotating the kiln to the end of the kiln having the lower floor surface. From the opening, the residue falls freely and is discharged. If necessary, a spiral blade or the like for scraping out the residue may be provided at the outlet of the residue.

  As the separation means, for example, a combination of a container containing the predetermined organic solvent supplied with the residue and a filter for solid-liquid separation of the organic solvent in which the organic acid is dissolved and the solid is used. it can. For example, a cooling unit that can cool the residue to room temperature may be provided between the discharging unit and the separating unit. For example, the residue can be cooled by blowing an inert gas at room temperature or low temperature.

  Furthermore, an embodiment of a method for selectively producing an organic acid or an alkali salt thereof according to the present invention will be described (hereinafter, unless otherwise specified, the organic acid or the alkali salt is collectively referred to as “organic acid”). ). The first object of this embodiment is to increase the selectivity of a predetermined organic acid. Therefore, this embodiment includes a case where hydrogen is not generated simultaneously with the organic acid.

The present embodiment includes generating an organic acid using an alkali metal carbonate instead of an alkali metal hydroxide. Since the alkali metal carbonate is a divalent alkali, the addition amount is 0.25 mol or more per 1 mol of carbon (C) contained in the saccharide. The upper limit of the addition amount is preferably 5 mol, and a more preferable range of the addition amount is 1 to 2.5 mol. By using an alkali metal carbonate, the selectivity of a predetermined organic acid may be improved, while CO and CO ₂ may be generated together with hydrogen and methane.

In order to selectively produce formic acid as the organic acid, it is preferable to react cellobiose with an alkali metal hydroxide or carbonate under heating conditions of 0 to 100 ° C. Since formic acid disappears in the reaction of the above formula 3 when the temperature is increased, it is more preferable to react the saccharide in this temperature range, particularly in the vicinity of room temperature. Note that hydrogen is not generated at a temperature of 100 ° C. or lower. In addition, by using cellobiose among saccharides, the ratio of the amount of formic acid produced (hereinafter referred to as selectivity) in the total amount of all organic acids produced is greatly improved. Further, alkali metal carbonates such as Na ₂ CO ₃ can also be used.

  In order to selectively produce acetic acid as an organic acid, it is preferable to react a saccharide with an alkali metal hydroxide under heating conditions of 250 to 450 ° C. Acetic acid is produced directly from saccharides, and is also produced by the decomposition of other produced organic acids at a temperature of 250 ° C. or higher. Acetic acid is very stable in the range of 250 to 450 ° C. Therefore, the selectivity of acetic acid is remarkably high in this temperature range.

  In order to selectively produce glycolic acid as the organic acid, it is preferable to react the polysaccharide and the alkali metal hydroxide under heating conditions of 220 to 300 ° C. Polysaccharides have a very high selectivity for glycolic acid compared to monosaccharides, disaccharides, and trisaccharides. Moreover, the selectivity of glycolic acid improves significantly by setting it as the temperature range of 220-300 degreeC. Since glycolic acid tends to decompose into hydrogen when water vapor is present, it is preferable not to add water vapor to the reaction atmosphere.

  In order to selectively produce lactic acid as an organic acid, it is preferable to react a monosaccharide with an alkali metal hydroxide or carbonate under heating conditions of 100 to 250 ° C. Monosaccharides have a very high selectivity for lactic acid compared to disaccharides, trisaccharides and polysaccharides. In addition, since lactic acid is decomposed into acetic acid when the temperature exceeds 250 ° C., the reaction temperature is set to 250 ° C. or lower.

  In order to selectively produce a dicarboxylic acid as an organic acid, it is preferable to react a saccharide with an alkali metal hydroxide under heating conditions of 140 to 380 ° C. As the dicarboxylic acid, mainly oxalic acid and succinic acid are produced, and maleic acid and glutaric acid are also contained in a small amount. In some cases, tartaric acid and malic acid are produced. As the saccharide, cellulose and starch are preferable, and the selectivity of succinic acid can be improved by using cellulose in particular. Moreover, the selectivity of succinic acid can also be improved by introducing water vapor. Of the dicarboxylic acids, oxalic acid has a tendency to decompose at around 300 ° C., so that the succinic acid selectivity can be improved by heating at 300 to 350 ° C.

  In addition, as an apparatus for selectively producing such a predetermined organic acid, for example, in the apparatus for simultaneously manufacturing the organic acid and hydrogen described above, the heating means is used to selectively generate the predetermined organic acid. The heating means for heating to a predetermined temperature may be used, and the quantitative supply means may be configured as a quantitative supply means for supplying a predetermined saccharide and an alkali metal hydroxide or carbonate to the reaction chamber.

  Furthermore, an embodiment of a method for producing an organic acid from a biomass resource not containing a saccharide according to the present invention will be described. In this embodiment, the case where hydrogen is not generated simultaneously with the organic acid is included.

  In the present embodiment, an organic acid is generated using biomass resources other than sugars. Lignin is used as such a biomass resource. Lignin is a major component of woody biomass along with cellulose and hemicellulose. However, among the woody biomass, cellulose is mainly used, and lignin is discarded. According to the present invention, since an organic acid can be generated using lignin, lignin can be used effectively.

  In order to produce an organic acid from lignin, it is preferable to react lignin and an alkali metal hydroxide under heating conditions of 140 to 360 ° C. As the organic acid, glyceric acid having a high added value is produced with high selectivity, and acetic acid and succinic acid are produced. A more preferable temperature range is 200 to 300 ° C.

  In addition, as an apparatus which manufactures organic acid using biomass resources other than such saccharides, for example, in the apparatus which manufactures organic acids using saccharides mentioned above, a heating means is heated to said predetermined temperature. As the heating means, the quantitative supply means supplies the lignin and the alkali metal hydroxide to the reaction chamber so that the alkali metal hydroxide is 0.5 to 10 mol with respect to 1 mol of carbon contained in the lignin. The thing of the structure used as the fixed_quantity | feed_rate supply means may be sufficient.

Example 1
Cellulose (Aldrich) 0.45 g (2.78 mmol) is placed on an alumina boat, and a 50 wt% NaOH aqueous solution (Wako Pure Chemical Industries, Ltd.) is added dropwise thereto in a predetermined amount (NaOH: 33.3 mmol). Both were mixed. And the experiment which produces | generates an organic acid and hydrogen from said sample using the normal pressure fixed bed flow-type reaction apparatus shown in FIG. 1 was conducted.

First, the sample 10 placed on the alumina boat 11 was placed in the center of the alumina reaction tube 3, and Ar purge (50 ml / min, 101 kPa) was performed for 30 minutes. Thereafter, the reaction tube 3 was heated by the electric furnace 4 and dried at 100 ° C. for 20 minutes in an Ar (20 ml / min, 101 kPa) atmosphere. Then, the temperature in the reaction tube 3 is increased from 100 ° C. to 250 ° C. at 2 ° C./min while introducing water vapor from the microfeeder 1 through the vaporizer 2, and when the temperature reaches 250 ° C., the temperature is increased. Discontinued and then cooled to room temperature. The water vapor was introduced at a water vapor supply rate of 9.4 ml / min, an Ar flow rate of 40 ml / min, and partial pressures of H ₂ O = 19.3 kPa and Ar = 81.7 kPa. The temperature of the vaporizer 2 was 100 ° C.

During this time, the gas generated in the alumina reaction tube 3 was introduced into the sampling device 6 through the trap device 5 held at 0 ° C. with ice. And in order to analyze a gaseous phase product, a part of gaseous phase was further introduce | transduced into the gas chromatograph 7 (The product made by GL Sciences, GC323, column: activated carbon). As a result, hydrogen was detected as a gas phase product, but methane, CO and CO ₂ were not detected.

  In addition, in order to qualitatively and quantitatively analyze the decomposition product generated by the reaction, the decomposition product is separated from the residue remaining on the alumina boat 11 in the alumina reaction tube 3, and the decomposition product is subjected to high performance liquid chromatography. Analysis was performed using a graph (HPLC). The procedure for separating the decomposition products from the residue is shown in FIG.

  First, the alumina boat 11 was taken out from the alumina reaction tube 3, and the soluble components in the residue remaining on the alumina boat 11 were dissolved in ion-exchanged water 21 (50 ml) as shown in FIG. Then, as shown in FIG. 2B, an aqueous phenol solution 22 (10 μmol) was added as an external standard substance. 5 ml of the sample solution 23 thus prepared was sampled and neutralized to about pH 0.8 by adding an aqueous HCl solution 24 (5 ml) as shown in FIG. Next, the neutralized sample solution 25 was filtered through a glass filter 26 as shown in FIG. And as shown in FIG.2 (e), 1.2 ml of filtered sample solutions 27 were extract | collected, and this was diluted with 15 ml of ion-exchange water 28, and it was set to about pH2. This diluted solution was analyzed by HPLC.

The setting conditions of HPLC are shown below.
Column: Synergi 4μ Hydro-RP80A (Phenomenex, 250 × 4.6 mm)
Detection wavelength: UV210nm
Column temperature: 25 ° C
Mobile phase: 20 mM KH ₂ PO 4 (aq.) + H ₃ PO ₄ (aq.) (PH 2.9)
Flow rate: 0.7 mL / min

  The analysis result by HPLC is shown in FIG. In addition, in FIG. 3 (a), the result of having analyzed 13 types of each organic acid by HPLC was shown. As shown in FIG. 3 (b), 14 products were detected, of which 4 products were found to be glycolic acid, formic acid, lactic acid, and acetic acid. The remaining 10 products do not correspond to the organic acids (oxalic acid, glyceraldehyde, tartaric acid, glyceric acid, malonic acid, maleic acid, succinic acid, propionic acid, glutaric acid) shown in FIG. Could not be identified.

(Example 2)
An organic acid and hydrogen are produced under the same conditions as in Example 1 except that the temperature rise is changed from 150 ° C. to 600 ° C. in place of 250 ° C. The amount of organic acid produced (μmol) Was measured. The result is shown in FIG.

  As shown in FIG. 4, formic acid was generated from around 200 ° C., and after reaching the maximum production amount (0.83 mmol) at about 240 ° C., it gradually decreased as the reaction temperature increased and disappeared completely at 265 ° C. . Glycolic acid was generated from around 200 ° C., reached the maximum production amount (3.74 mmol) at about 265 ° C., and then gradually decreased with the increase in reaction temperature, and disappeared completely at 390 ° C. Lactic acid was generated from around 200 ° C., reached a maximum production amount (0.27 mmol) at about 240 ° C., then gradually decreased with an increase in reaction temperature, and disappeared completely at 330 ° C. Acetic acid was generated from around 240 ° C., reached the maximum production amount (1.52 mmol) at about 330 ° C., then gradually decreased with increasing reaction temperature, and disappeared completely at 600 ° C.

  Instead of cellulose, glycolic acid, which is one of the products, was reacted with NaOH under the flow of water vapor to generate hydrogen, and the hydrogen generation rate (mmol / min) was measured. The result is shown in FIG. As shown in FIG. 5, glycolic acid decomposes from around 280 ° C. to generate hydrogen. After the hydrogen generation rate reaches a maximum at 330 ° C., the hydrogen generation rate gradually decreases, and finally at 390 ° C. Generation is almost no longer observed.

  From this result, the production amount of glycolic acid shows the maximum at 280 ° C. (FIG. 4) because the decomposition of glycolic acid starts when the temperature exceeds 280 ° C. (FIG. 5). It turned out that it became zero at 390 ° C. (FIG. 4) because glycolic acid was completely decomposed and disappeared when the temperature exceeded 390 ° C. (FIG. 5). Experiments were conducted in the same manner with other organic acids such as formic acid, lactic acid, and acetic acid, and it was found that the change in the amount of organic acid produced corresponds well with the temperature at which the organic acid decomposes to produce hydrogen.

(Example 3)
After raising the temperature inside the reaction tube 3 to a predetermined temperature, the reaction tube 3 was kept constant for 2 to 3 hours, and the reaction was continued until almost no hydrogen production was observed. An organic acid was produced, and the amount of organic acid produced was measured. The result is shown in FIG.

  As shown in FIG. 6, it was found that when the reaction temperature was kept constant, the organic acid was generated at a lower temperature than when the reaction temperature was not kept as shown in FIG. For example, the amount of glycolic acid produced was about 3 mmol at 200 ° C. when kept at a constant temperature, which was equivalent to the result at 250 ° C. when cooled immediately after reaching the predetermined temperature. . That is, a considerable amount of glycolic acid was produced at a low temperature of about 50 ° C. In addition, other organic acids were also generated at a lower temperature. Formic acid and lactic acid were produced from about 150 ° C., and acetic acid was produced from 200 ° C.

  Further, the temperature at which the production amount of each organic acid reaches the maximum has also been shifted to a low temperature when it is kept at a constant temperature. Formic acid and lactic acid reached the maximum at 200 ° C, glycolic acid at 250 ° C, and acetic acid at 280 ° C. Thus, it has been found that by maintaining the reaction temperature constant, the amount of organic acid produced can be increased even at a low temperature.

Example 4
D-glucose (manufactured by Wako Pure Chemical Industries, Ltd.) and sucrose (manufactured by Wako Pure Chemical Industries, Ltd.) were used in such a weight that the carbon content in the sample was 0.20 g (16.7 mmol). The organic acid and hydrogen were produced under the same conditions as in Example 2 except that the measurement was performed at 9 ° C./min, and measurement was performed between 100 ° C. and 600 ° C., and the hydrogen production rate (μmol / min). The result is shown in FIG. For reference, the results for cellulose are also shown.

As shown in FIG. 7, it was confirmed that glucose and sucrose also showed excellent hydrogen production rates in the range of 200 ° C. to 350 ° C. like cellulose. That is, glucose and sucrose were also found to have disappeared by decomposition of most organic acids into hydrogen at about 350 ° C., similar to cellulose. In addition, although any saccharide produced a relatively large amount of methane at around 400 ° C., CO and CO ₂ were not produced.

(Example 5)
Under the same conditions as in Example 1 except that 0.45 g of D-glucose, D-fructose, D-mannose, cellobiose, sucrose, maltose, maltotriose, denven and lignin were used instead of cellulose. An organic acid and hydrogen were produced, and the amount of organic acid produced (μmol) was measured. The result is shown in FIG. In addition, the result of cellulose was also described.

  As shown in FIG. 8, in the same manner as cellulose, a large amount of organic acids such as formic acid, acetic acid, glycolic acid, and lactic acid were produced from monosaccharides, disaccharides, trisaccharides, and other polysaccharides such as starch. It could be confirmed. On the other hand, an organic acid was also generated from lignin, but the amount thereof was extremely small compared to saccharides.

  Moreover, in each saccharide, the ratio (%) of the amount of each organic acid when the total amount of the generated four types of organic acids is 100 is shown in FIG. As shown in FIG. 9, the selectivity for lactic acid is the highest at about 60% or more for monosaccharides, followed by about 40-50% for disaccharides and trisaccharides, and extremely about 5% for polysaccharides. It was low. On the other hand, the selectivity of glycolic acid was remarkably high at about 70% or more for polysaccharides, about 30% for trisaccharides, about 20% for disaccharides, and 5-10% for monosaccharides.

(Example 6)
Example, except that 0.45 g (2.50 mmol) of D-glucose was used instead of cellulose, and the temperature elevation temperature was changed from room temperature (25 ° C.) to 600 ° C. instead of 250 ° C. The organic acid and hydrogen were produced under the same conditions as in Example 1, and the production amount of the organic acid was measured. The result is shown in FIG.

  As shown in FIG. 10A, lactic acid was produced in a large amount of 2.5 mmol at 250 ° C. or lower, and acetic acid was produced in a large amount of 3.9 mmol at 250 to 450 ° C. Formic acid and glycolic acid were also confirmed to be produced, but the amounts were very small compared to lactic acid and acetic acid. Lactic acid was produced at about 1200 μmol even at room temperature. Formic acid and glycolic acid were 300-500 μmol, which was a small amount compared to lactic acid, but was produced even at room temperature.

  In addition, since the production of lactic acid and acetic acid was clearly separated around 250 ° C., an organic acid production experiment was similarly conducted using lactic acid (2.5 mmol) instead of D-glucose. The result is shown in FIG. As shown in FIG. 10B, when the temperature exceeded 250 ° C., lactic acid was consumed and acetic acid was produced. Therefore, it is considered that 1.3 mmol of 3.9 mmol of acetic acid generated from D-glucose was generated via lactic acid.

(Example 7)
Example 1 except that 0.45 g (1.31 mmol) of cellobiose was used instead of cellulose, and the temperature elevation temperature was changed from room temperature (25 ° C.) to 600 ° C. instead of 250 ° C. Hydrogen and organic acid were produced under the same conditions, and the production amounts of hydrogen, methane and organic acid were measured. The result is shown in FIG.

As shown in FIG. 11, hydrogen was generated from 200 ° C. in cellobiose, and after reaching the maximum generation amount at about 300 ° C., hydrogen was generated in a trace amount from 300 to 500 ° C. In addition, a relatively large amount of methane was produced at around 400 ° C., but no production of CO and CO ₂ was observed. Regarding the production of organic acids, a large amount of formic acid was produced at room temperature, and a small amount of lactic acid and glycolic acid were produced. In the temperature range of 100 ° C. to 200 ° C., the amount of formic acid produced decreased, and the same amount of formic acid and lactic acid were produced. The production of formic acid and lactic acid disappeared at 300 ° C., and a large amount of acetic acid was produced. That is, the selectivity of formic acid was very high in the low temperature range of 25 to 100 ° C.

(Example 8)
After the heating to 250 ° C., the organic acid and hydrogen were produced in the same manner as in Example 1 except that the time until cooling was changed to 0 to 120 minutes, and the production amount of the organic acid was measured. The result is shown in FIG. Moreover, it replaced with the cellulose and also experimented also about glucose on the same conditions as this. The result is shown in FIG.

  As shown in FIG. 12 (a), it was found that the amount of glycolic acid produced was larger when the reaction time was provided than when the temperature was 250 ° C. and then rapidly cooled. Further, it was found that the amount of glycolic acid produced was almost constant regardless of the length of the reaction time, and was stable at 250 ° C.

As shown in FIG. 12B, as the reaction time increased, the amount of lactic acid produced decreased, and conversely the amount of acetic acid produced increased. This showed that lactic acid reacted with NaOH and converted to acetic acid and Na ₂ CO ₃ . Therefore, it was found that acetic acid can be selectively generated even at 250 ° C. by increasing the reaction time. Formic acid, both cellulose and glucose, had a drastically reduced production amount when a reaction time was provided, compared to the case of rapid cooling. From this, it was found that formic acid was easily converted to hydrogen and Na ₂ CO ₃ at a temperature of 250 ° C.

Example 9
An organic acid was added under the same conditions as in Example 1 except that no alkali was added, LiOH, KOH, RbOH (more than 33.3 mmol), and Ca (OH) ₂ (16.7 mmol) were used instead of NaOH. And the production | generation of hydrogen was performed and the production amount of the organic acid was measured. The result is shown in FIG. In addition, the result of NaOH is also described.

As shown in FIG. 13, KOH had a higher yield of organic acid than NaOH. Moreover, although RbOH and LiOH were also low compared with these, it was confirmed that a large amount of organic acids are produced. On the other hand, in Ca (OH) ₂ , the production of organic acid was confirmed, but the yield was extremely low. Further, when no alkali was added, no organic acid was detected.

(Example 10)
The same conditions as in Example 1 except that Na ₂ CO ₃ (16.7 mmol) was used instead of NaOH, and the temperature elevation temperature was changed from 100 ° C. to 600 ° C. instead of 250 ° C. Then, organic acids and hydrogen were produced, and the production amounts of hydrogen, methane, CO, CO ₂ and organic acids were measured. The results are shown in FIGS. 14 (b) and 15 (b). For comparison, the results of NaOH are shown in FIGS. 14 (a) and 15 (a).

As shown in FIG. 14B, when Na ₂ CO ₃ was used, hydrogen was hardly detected in the range of 250 to 450 ° C., and CO and CO ₂ were detected instead. On the other hand, as shown in FIG. 15B, when Na ₂ CO ₃ was used, the production of glycolic acid and acetic acid was drastically reduced compared to NaOH. Thus, since the production of glycolic acid and acetic acid was greatly reduced, the selectivity for formic acid production was remarkably increased.

(Example 11)
Except that the molar ratio of NaOH and cellulose was changed to 0, 2.9 mmol, 8.6 mmol, 16.7 mmol, 51.1 mmol and 66.6 mmol in place of 33.3 mmol of NaOH. The organic acid and hydrogen were produced under the same conditions as in Example 1, and the production amount of the organic acid was measured. The result is shown in FIG. For comparison, the result of 33.3 mmol is also shown.

As shown in FIG. 16, it was found that the amount of formic acid and glycolic acid produced changed greatly by changing the molar ratio of NaOH and cellulose. When the molar ratio of NaOH to cellulose was 12 or less, the production amount and selectivity of formic acid increased and glycolic acid decreased. On the other hand, when the molar ratio of NaOH to cellulose exceeded 12, the amount of glycolic acid produced and the selectivity increased. Furthermore, formic acid disappeared when the molar ratio of NaOH to cellulose was 24 or more. In addition, when the molar ratio of NaOH to cellulose was 1, generation of hydrogen could not be confirmed, and generation of CO and CO ₂ was confirmed. Hydrogen production was confirmed when the molar ratio of NaOH to cellulose was 3 or more.

(Example 12)
When reacting cellulose and NaOH, organic acid and hydrogen were produced under the same conditions as in Example 1 except that no water vapor was introduced, and the amount of organic acid produced was measured. The result is shown in FIG. In addition, the result at the time of introduce | transducing water vapor | steam for a comparison is also described collectively.

  As shown in FIG. 17, the amount of each organic acid produced was greater when no water vapor was introduced. Therefore, for each organic acid of formic acid (9.71 mmol), lactic acid (5.36 mmol), glycolic acid (5.93 mmol), and acetic acid (2.80 mmol), both with and without the introduction of water vapor Hydrogen was produced by reacting with NaOH under the conditions, and the production rate of hydrogen and methane (μmol / min) was measured. The temperature raising temperature was in the range of 150 ° C to 550 ° C. The result is shown in FIG. In FIG. 18, black marks indicate a case where water vapor is introduced, and white marks indicate a case where water vapor is not introduced. In addition, it describes also about the result of a cellulose.

  As shown in FIG. 18B, in the vicinity of 600K, the rate of hydrogen generation was higher when water vapor was introduced. From this, it is considered that the introduction of water vapor promotes the further decomposition of the organic acid generated from cellulose into hydrogen. Further, as shown in FIG. 18 (a), in the vicinity of 600K, the rate of methane formation was lower when water vapor was introduced. From this, it is considered that the introduction of water vapor suppresses the further decomposition of the organic acid generated from cellulose into methane.

(Example 13)
In place of the reagent cellulose, 0.45 g of pulp mill material (Havix) generated during the manufacturing process in the pulp nonwoven factory was used, and 2.66 g of NaOH aqueous solution (1 mol of carbon (C) of pulp mill material) 12 mol), 50 ml of 3 mmol / L perchloric acid aqueous solution was used as the reaction product solution, and measurement was performed by liquid chromatography (HPLC) without neutralizing the reaction product solution. The organic acid and the conditions under the same conditions as in Example 1 except that the sample injection amount to HPLC was 10 μL, and that GL-C-610H-S manufactured by Hitachi Chemical Co., Ltd. was used as the HPLC column. Hydrogen was generated, and organic acid identification and production were measured. The results are shown in Table 1.

  As shown in Table 1, in Example 13, 15 types of products were detected, and 11 of them could be identified. The identified products were found to be oxalic acid, maleic acid, gluconic acid, succinic acid, glutaric acid and propionic acid in addition to the above-mentioned four products of glycolic acid, lactic acid, formic acid and acetic acid. The remaining four products did not fall under the organic acids of tartaric acid, D-glucuronic acid, malic acid, glyceric acid, and levulinic acid, and could not be identified.

(Example 14)
The organic acid and hydrogen are produced under the same conditions as in Example 13 except that the temperature is raised to 250 ° C. and then cooled for 30 minutes, 1 hour or 2 hours after the reaction time has elapsed. Was measured. In addition, the same experiment was conducted except that the reaction was performed without introducing any water vapor at each reaction time. These results are shown in Table 1. As shown in Table 1, by providing the reaction time, the production amounts of organic acids such as oxalic acid, gluconic acid, succinic acid, glycolic acid, and acetic acid increased dramatically.

(Example 15)
Except that the temperature was changed from 250 ° C. to 300 ° C. and the reaction time was changed to 0 or 1 hour, an organic acid and hydrogen were produced under the same conditions as in Example 14, and the identification and production amount of the organic acid were determined. It was measured. The results are shown in Table 1.

  As shown in Table 1, when the reaction time was provided at 300 ° C., the production amounts of oxalic acid and glycolic acid were greatly reduced, and the production amount of acetic acid was increased. Gluconic acid disappeared after a reaction time of 1 hour when water vapor was introduced, but the amount of production increased when water vapor was not introduced. Conversely, when steam was introduced, the amount of succinic acid increased by providing a reaction time of 1 hour, but when steam was not introduced, the amount of succinic acid decreased.

(Example 16)
Except that the temperature was changed from 250 ° C. to 350 ° C. and the reaction time was changed to 0 or 1 hour, an organic acid and hydrogen were produced under the same conditions as in Example 14, and the identification and production amount of the organic acid were determined. It was measured. The results are shown in Table 1.

  As shown in Table 1, at 350 ° C., glycolic acid was not produced when water vapor was not introduced. Moreover, when water vapor | steam was introduce | transduced, the gluconic acid was not produced | generated. And when reaction time was provided, the production amount of these gluconic acid and glycolic acid decreased. The amount of succinic acid and acetic acid significantly decreased when no steam was introduced.

(Example 17)
The organic acid and hydrogen were produced under the same conditions as in Example 14 except that the temperature and reaction time were changed to 200 ° C. for 1 hour, 370 ° C. for 1 hour, and 390 ° C. for 1 hour. The amount produced was measured. Also, the temperature and reaction time were changed to 150 ° C for 1 hour, 350 ° C for 30 minutes, 350 ° C for 2 hours, 370 ° C for 1 hour, 390 ° C for 30 minutes, 390 ° C for 1 hour, and all An organic acid and hydrogen were produced under the same conditions as in Example 14 except that no water vapor was introduced, and the amount of organic acid produced was measured. These results are shown in Table 2.

  As shown in Table 2, when compared with the case where water vapor was not introduced at 350 ° C., the total amount of organic acid produced decreased with the passage of the reaction time, and only a trace amount of organic acid was obtained after 1 to 2 hours. I couldn't. Further, when compared with the case where the reaction time was 1 hour and no water vapor was introduced, the total amount of organic acid produced decreased as the temperature rose, and almost no organic acid could be obtained at 390 ° C.

(Example 18)
Organic acid and hydrogen were used under the same conditions as in Example 13, except that 0.45 g of reagent cellulose (Aldrich) was used instead of pulp milling material, and that the temperature was raised to 350 ° C. in addition to 250 ° C. The organic acid was identified and the amount produced was measured. The results are shown in Table 3.

  As shown in Table 3, when the sample cellulose was used at 250 ° C., the results were almost the same as when the pulp milling material was used (see the same conditions in Examples 13 and 14). However, at 350 ° C., when the reagent cellulose is used, gluconic acid is not generated, whereas succinic acid and acetic acid are generated, compared with the case of using the pulp milling material (see the same conditions in Example 16). The amount was high and varied greatly.

Example 19
The addition amount of NaOH aqueous solution increased from 12 mol to 18 mol with respect to 1 mol of carbon (C) of the pulp mill material, kept at 250 ° C. or 350 ° C. for 1 hour, and did not introduce water vapor The organic acid and hydrogen were produced under the same conditions as in Example 13, except that the organic acid was identified and the amount produced. The results are shown in Table 3.

  As shown in Table 3, when the molar ratio of NaOH / pulp scrap carbon is increased to 18 at 250 ° C., compared with the case where the molar ratio is 12 (see the same conditions in Example 14). Besides, the production amount of glycolic acid and acetic acid increased, and D-glucuronic acid was produced. On the other hand, the production of gluconic acid was lost. At 350 ° C., the amount of organic acid produced was small both when the molar ratio was increased to 18 and when the molar ratio was 12 (see the same conditions in Example 16).

(Example 20)
Example 13 except that KOH was used instead of NaOH and held at 250 ° C. or 350 ° C. for 1 hour, or BaOH was used and held at 250 ° C. for 1 hour, and no water vapor was introduced. The organic acid and hydrogen were produced under the same conditions as above, and the identification and production amount of the organic acid were measured. The results are shown in Table 3. In addition, since BaOH had very low solubility in water, 6 mol was added to 1 mol of carbon in the pulp scrap.

  As shown in Table 3, at 250 ° C., when KOH was used, the amount of formic acid and oxalic acid increased compared to when NaOH was used (see the same conditions in Example 14), while lactic acid And the production amount of gluconic acid decreased. When BaOH was used, almost no organic acid was produced. At 350 ° C., the amount of acetic acid, maleic acid, and propionic acid increased when KOH was used and when NaOH was used (see the same conditions in Example 16), and the amount of organic acid generated The total also increased significantly.

(Example 21)
Instead of pulp milling material, 0.45g of lignin (manufactured by Nakarai-Tex), starch (manufactured by the company), cedar and cypress, that it was held at 250 ° C for 1 hour, and that water vapor was not introduced Except for this, an organic acid and hydrogen were produced under the same conditions as in Example 13, and the identification and production amount of the organic acid were measured. The results are shown in Table 3.

  As shown in Table 3, when lignin was used, glyceric acid was produced with high selectivity, and in addition, acetic acid and succinic acid were produced. When starch was used, glycolic acid was produced with a high selectivity like cellulose. When cedar was used, glycolic acid was produced with a high selectivity like cellulose, but gluconic acid was not produced at a point different from cellulose. In the case of using cypress, glycolic acid was produced with high selectivity like cellulose, but lactic acid and gluconic acid were not produced in the point different from cellulose.

(Example 22)
The organic acid and hydrogen were produced under the same conditions as in Example 13 except that lignin was used, the temperature was maintained at 150 to 350 ° C. for 1 hour, and water vapor was not introduced. The amount produced was measured. The results are shown in Table 4. Moreover, the same test was implemented also about the case where water vapor | steam was introduce | transduced at the temperature of 200 degreeC. In addition, the reaction product solution was neutralized under the conditions of 200 ° C. and 300 ° C. and measured by a liquid chromatograph. When neutralization was performed, the amount of oxalic acid produced could not be measured.

  As shown in Table 4, glyceric acid was mainly produced from lignin at any temperature of 150 to 350 ° C., regardless of whether or not water vapor was introduced. In particular, glyceric acid was produced with high selectivity in a temperature range of 200 to 300 ° C.

It is a schematic diagram which shows the outline of the fixed bed flow reaction apparatus used in the Example. It is a schematic diagram which shows the analysis procedure of the product in the residue in an Example. It is a graph which shows the analysis result of the organic acid by HPLC. It is a graph which shows the production amount of each organic acid at the time of quenching after reaching reaction temperature. It is a graph which shows the hydrogen production | generation rate from glycolic acid. It is a graph which shows the production amount of each organic acid at the time of hold | maintaining for 2-3 hours after reaction temperature attainment. It is a graph which shows the hydrogen production | generation rate from each saccharides. It is a graph which shows the organic acid production amount from each saccharides. It is a graph which shows the selectivity of the organic acid from each saccharides. (A) is a graph which shows the organic acid production amount from glucose, (b) is a graph which shows the organic acid production amount from lactic acid. (A) is a graph which shows the production | generation rate of hydrogen and methane from cellobiose, (b) is a graph which shows the organic acid production amount from cellobiose. (A) is a graph which shows the organic acid production | generation amount from a cellulose, (b) is a graph which shows the organic acid production | generation amount from glucose. It is a graph which shows the organic acid production | generation amount at the time of using the hydroxide of various alkali metals. Hydrogen, methane, a graph showing the rate of formation of CO and CO _2, (a) in the case of using NaOH, a graph in the case of using the (b) is Na ₂ CO _3. Is a graph showing the organic acid production amount, (a) shows the case of using NaOH, a graph in the case of using the (b) is Na ₂ CO _3. It is a graph which shows the organic acid production | generation amount when changing the molar ratio of NaOH and a cellulose. It is a graph which shows the organic acid production | generation amount when not introduce | transducing water vapor | steam. It is a graph which shows the production | generation speed | rate of the gas from each organic acid when not having introduce | transduced water vapor | steam, (a) is methane, (b) is a graph which shows hydrogen.

Explanation of symbols

1 Microfeeder 2 Vaporizer 3 Alumina reaction tube 4 Electric furnace 5 Trap device 6 Sampling device 7 Gas chromatograph 10 Sample (sugar + alkali)
11 Alumina boat 21, 27 Ion exchange water 22 Phenol aqueous solution 23 Hydrochloric acid aqueous solution 26 Glass filter

Claims (9)

  Including a step of simultaneously reacting a saccharide with an alkali metal hydroxide to generate hydrogen and an organic acid or an alkali salt thereof under a heating condition of 150 to 450 ° C. and in an oxygen-free atmosphere, the saccharide and the alkali metal The manufacturing method of the organic acid or its alkali salt which makes the molar ratio of the hydroxide of 0.5-10 mol of alkali metal hydroxide with respect to 1 mol of carbon contained in saccharides.   The method for producing an organic acid or an alkali salt thereof according to claim 1, wherein a biomass resource mainly composed of cellulose is used as the saccharide.   A method for producing an organic acid or an alkali salt thereof, wherein cellobiose and an alkali metal hydroxide or carbonate are reacted under heating conditions of 0 to 100 ° C. to selectively produce formic acid or an alkali salt thereof.   A method for producing an organic acid or an alkali salt thereof, wherein a saccharide and an alkali metal hydroxide are reacted under a heating condition of 250 to 450 ° C. to selectively produce acetic acid or an alkali salt thereof.   A method for producing an organic acid or an alkali salt thereof, wherein a polysaccharide and an alkali metal hydroxide are reacted under a heating condition of 220 to 300 ° C. to selectively produce glycolic acid or an alkali salt thereof.   A process for producing an organic acid or an alkali salt thereof, which selectively produces lactic acid or an alkali salt thereof by reacting a monosaccharide with an alkali metal hydroxide or carbonate under heating conditions of 100 to 250 ° C.   The manufacturing method of the organic acid or its alkali salt which makes saccharides and the hydroxide of an alkali metal react under the heating conditions of 140-380 degreeC, and produces | generates dicarboxylic acid or its alkali salt.   The manufacturing method of the organic acid or its alkali salt which makes a lignin and the hydroxide of an alkali metal react under the heating conditions of 140-360 degreeC, and produces | generates an organic acid or its alkali salt.   A reaction chamber under an oxygen-free atmosphere in which hydrogen and an organic acid or an alkali salt thereof are simultaneously generated by a reaction between a saccharide and an alkali metal hydroxide; and a heating means for setting the temperature of the reaction chamber to 150 to 450 ° C .; Quantitative supply for continuously supplying the saccharide and the alkali metal hydroxide to the reaction chamber such that the alkali metal hydroxide is 0.5 to 10 mol per 1 mol of carbon contained in the saccharide. An organic acid comprising: means; a pipe for discharging hydrogen generated in the reaction chamber; and a discharging means for continuously removing a solid residue containing an organic acid or an alkali salt thereof from the reaction chamber. Alkali salt production equipment.

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