JP6694641B2 - Process for producing α, β-unsaturated carboxylic acid such as acrylic acid and its derivatives - Google Patents

Description

  The present invention relates to a novel method for producing an α, β-unsaturated carboxylic acid such as acrylic acid or a derivative thereof. More specifically, the present invention uses a 2-hydroxycarboxylic acid such as lactic acid or a derivative thereof as a raw material, and in the presence of a metal catalyst such as copper, the raw material is treated with high-temperature high-pressure water, The present invention provides a new technology for synthesizing α, β-unsaturated carboxylic acids such as acrylic acid and their derivatives.

  Various methods for synthesizing α, β-unsaturated carboxylic acids have been reported, for example, a production method by a gas phase dehydration method in the presence of a solid catalyst has been reported (Patent Document 1). In particular, the synthesis of acrylic acid from lactic acid is a technical problem that has been attracting attention for many years as a technique for breaking away from petroleum-derived raw materials because lactic acid is easily obtained from fermentation of natural products. The compound obtained by the dehydration reaction of lactic acid is as shown in FIG. 1, in which lactic acid is used as a raw material through Path I, acetaldehyde, through Path II, pentanedione, through Path III, acrylic acid, and Path IV. Via propanediol, via Path I, then via Path V, acetic acid, via Path III, via Path VI, propionic acid, via Path III, via Path VII, ethylene and mainly seven types of Examples of the product include polylactic acid obtained by polymerizing lactic acid itself. Among them, acrylic acid has been studied as much as polylactic acid because it is a raw material for water-absorbing polymers and the like. Acrylic acid and acrylic acid ester can be obtained from lactic acid or its ester by a dehydration reaction via Path III (Non-Patent Documents 1 to 10).

As a method for producing acrylic acid by dehydrating lactic acid, 1) use of inorganic acid, 2) use of organic acid, 3) use of solid acid, 4) high temperature high pressure water (HPHT-H ₂ O) or subcritical / supercritical Examples include the use of critical water. In particular, when HPHT-H ₂ O or subcritical / supercritical water is used, Hastelloy C-276 (Non-Patent Document 1, Non-Patent Document 3) and alumina (excluding Hastelloy C-276, Non-Patent Document 1), Inconel 625 (Non-Patent Document 2), quartz (Non-Patent Document 6) and the like are used, and the reaction is performed by a system having a simple structure.

  However, in these synthetic methods, although the conversion rate of lactic acid is high, the yield of acrylic acid is about 53% at the maximum, and the low efficiency is a problem of acrylic acid synthesis using lactic acid as a raw material.

JP-A-3-167157

William Shu-Lai Mork and Michael Jerry Antal, Jr., Formation of Acrylic Acid from Lactic Acid in supercritical water, J. Org. Chem., 1989, 54, 4596-4602. T.M.Aida, A. Ikarashi, Y. Saito, M. Watanabe, R.L. Smith, K. Arai, J. Supercritical. Fluids 50 (2009) 257. C.T. Lira, P.J. McCrackin, Ind. Eng. Chem. Res. 32 (1993) 2608. Z. Zhang, Y. Qu, S. Wang, J. Wang, J. Mol. Catal. A 323 (2010) 91. G.C.Gunter, D.J.Miller, J.E. Jackson, J. Catal. 148 (1994) 252. D.C. Wadley, M.S. Tam, P.B.Kokitkar, J.E. Jackson, D.J. Miller, J. Catal. 165 (1997) 162. M.S. Tam, G.C. Gunter, R. Craciun, D.J. Miller, J.E. Jackson, Ind. Eng. Chem. Res. 36 (1997) 3505. H. Wang, D. Yu, P. Sun, J. Yan, Y. Wang, H. Huang, Catal. Commun. 9 (2008) 1799. J. Zhang, Y. Zhao, M. Pan, X. Feng, W. Ji, C.T. Au, ACS Catal. 1 (2011) 32. P. Sun, D. Yu, K. Fu, M. Gu, Y. Wang, H. Huang, H. Ying, Catal. Commun. 10 (2009) 1345.

  The present invention is based on the background of the prior art as described above, and obtains α, β-unsaturated carboxylic acid or its derivative from 2-hydroxycarboxylic acid or its derivative at the same level as or higher than that of the prior art. It is an object of the present invention to provide a production method for selectively synthesizing at a rate (a yield of about 40% or more) and a selectivity, and particularly when synthesizing acrylic acid from lactic acid that is 2-hydroxycarboxylic acid, It is an object of the present invention to provide a production method for selectively synthesizing acrylic acid by suppressing the production of products such as propionic acid, acetic acid and carbon dioxide.

  Under these circumstances, in view of the above-mentioned conventional technique, the present inventors have conducted various studies with the aim of developing a method for synthesizing acrylic acid from lactic acid using high-temperature high-pressure water as a medium and a catalyst. , Noticed that the reaction vessel performing the reaction was catalytic, and succeeded in establishing a method for selectively synthesizing acrylic acid from lactic acid by improving the catalytic action, and to complete the present invention. I arrived.

（９）前記２−ヒドロキシカルボン酸及び／又はその誘導体が、乳酸、乳酸メチル、乳酸エチル、乳酸プロピル、２−ヒドロキシイソ酪酸、２−ヒドロキシイソ酪酸メチル、２−ヒドロキシイソ酪酸エチル、２−ヒドロキシイソ酪酸プロピル、乳酸アミド、Ｎ，Ｎ−ジメチル乳酸アミド、及び／又は、乳酸チオエステルであり、α,β−不飽和カルボン酸及び／又はその誘導体が、アクリル酸、アクリル酸エステル、メタクリル酸、メタクリル酸エステル、アクリルアミド、ジメチルアクリルアミド、及び／又は、アクリル酸チオエステルであることを特徴とする前記(１)〜(８)のいずれか１項に記載の製造方法。
（１０）前記２−ヒドロキシカルボン酸及び／又はその誘導体が、乳酸、乳酸エステル、及び／又は、乳酸アミドであることを特徴とする前記(１)〜(９)のいずれか１項に記載の製造方法。 The present invention for solving the above-mentioned problems comprises the following technical means.
(1) In a reaction of obtaining an α, β-unsaturated carboxylic acid and / or a derivative thereof from 2-hydroxycarboxylic acid and / or a derivative thereof, a metal (however, in a high temperature / high pressure water of 200 ° C. to 500 ° C., 10 MPa to 50 MPa, 2-hydroxycarboxylic acid, characterized in that the reaction is carried out in the presence of austenitic stainless steel, nickel chromium molybdenum alloy, nickel chromium iron niobium alloy, brass , or L-type zeolite, modified L-type zeolite . And / or a production method of synthesizing an α, β-unsaturated carboxylic acid and / or a derivative thereof from the derivative thereof.
(2) The metal is selected from aluminum, silicon, titanium, vanadium, iron, nickel, copper, zinc, zirconium, molybdenum, ruthenium, rhodium, palladium, silver, tantalum, tungsten, rhenium, iridium, platinum, gold and lead. The manufacturing method according to (1) above, wherein the manufacturing method is one kind of metal or an alloy containing two or more kinds.
(3) The manufacturing method according to (1) or (2) above, wherein the metal has a shape of particles, wires, or tubes.
(4) The manufacturing method according to (3), wherein the pipe has an inner diameter of 0.1 mm or more and 5 mm or less.
(5) The manufacturing method according to (3), wherein the wire has a diameter of 1 μm or more and 5 mm or less and a length of 1 cm or more.
(6) The production method according to (3), wherein the particles have a diameter of 1 μm or more and 5 mm or less.
(7) The 2-hydroxycarboxylic acid and / or its derivative is 2-hydroxycarboxylic acid, 2-hydroxycarboxylic acid ester, 2-hydroxycarboxylic acid amide, and / or 2-hydroxycarboxylic acid thioester. The manufacturing method according to any one of 1) to (6).
(8) The 2-hydroxycarboxylic acid and / or the 2-hydroxycarboxylic acid ester is a compound represented by the general formula (I) (wherein R ₁ and R ₂ are each independently hydrogen or alkyl). Group, cycloalkyl group, vinyl group, aryl group such as phenyl group, nitrogen-containing heteroaryl group, amino group (-NR'R "), hydroxyl group, thiol group, alkoxy group (-OR), thioalkoxy group ( -SR), aldehyde group, carboxy group, alkylcarbonyl group (-C (O) R), alkyl ester group (-C (O) OR), alkylamide (-C (O) NR'R "), benzyl group, a halogen (F, Cl, Br, I ), a phosphonyl group (-P (O) (OR) 2), a cyano group, a sulfonyl group _{(-S (O) 2 R)} , a sulfinyl group (-S (O ) R) (in the formula, R ′ and R ″ each independently represent hydrogen or an alkyl group, R represents an alkyl group), R ₃ represents hydrogen, (1 group selected from an alkyl group, a cycloalkyl group, a vinyl group, an aryl group, and an amino group is shown.)), The production method according to (7) above.

(9) The 2-hydroxycarboxylic acid and / or its derivative is lactic acid, methyl lactate, ethyl lactate, propyl lactate, 2-hydroxyisobutyric acid, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, 2-hydroxy. Propyl isobutyrate, lactic acid amide, N, N-dimethyl lactate amide and / or lactic acid thioester, wherein α, β-unsaturated carboxylic acid and / or its derivative is acrylic acid, acrylic acid ester, methacrylic acid, methacrylic acid The method according to any one of (1) to (8) above, wherein the method is an acid ester, acrylamide, dimethylacrylamide, and / or acrylic acid thioester.
(10) The 2-hydroxycarboxylic acid and / or derivative thereof is lactic acid, lactic acid ester, and / or lactic acid amide, according to any one of (1) to (9) above. Production method.

  According to the production method of the present invention, an α, β-unsaturated carboxylic acid such as acrylic acid or a derivative thereof can be produced from 2-hydroxycarboxylic acid or a derivative thereof at a high yield of 40% or more and a selectivity. . Moreover, the content of impurities (acetic acid, propionic acid) in the product is small. Further, the yield and the selectivity can be improved to about 80% or more or about 90% or more by appropriately adjusting the reaction conditions such as the reaction temperature condition and the pressure condition.

The drawing which shows the example of a compound obtained by the dehydration reaction of lactic acid or the reaction pathway including this dehydration reaction. Schematic which shows the high temperature high pressure microreactor used for manufacture of the acrylic acid of an Example. The drawing which shows a part of double tube (reaction tube) which comprises the reaction part of the high temperature high pressure microreactor used in the Example. The drawing which shows the GC chart of the product sample obtained in Example 1. Drawing showing the yield of the product compound (acrylic acid, hydroxyacetone, acetic acid, propionic acid, acetaldehyde, 3-methyl-2 (5H) -furanone) obtained at each reaction temperature (300 to 420 ° C) of Example 1. . 3 is a drawing showing a cross section of a reaction tube that constitutes a reaction part of the high-temperature high-pressure microreactor used in Example 2 and a copper wire that extends in the tube axial direction over the entire reaction part inside thereof. 3 is a view showing a reaction tube constituting a reaction part of the high temperature and high pressure microreactor used in Example 2 and a copper wire having a diameter of 0.35 mm and a length of 2.57 mm, which is irregularly arranged therein. Drawing showing the yield of the product compound (acrylic acid, hydroxyacetone, acetic acid, propionic acid, acetaldehyde, 3-methyl-2 (5H) -furanone) obtained at each reaction temperature (300 to 420 ° C) of Example 3. .

Next, the present invention will be described in more detail.
The present invention is a method for producing an α, β-unsaturated carboxylic acid or a derivative thereof by dehydrating 2-hydroxycarboxylic acid or a derivative thereof in high-temperature high-pressure water, in which a metal (however, , Austenitic stainless steel, nickel-chromium-molybdenum-based alloy, nickel-chromium-iron-niobium-based alloy, brass) are present to suppress the disordered dehydration reaction by water and selectively synthesize the target substance. Is the method.

  As the reaction in the present invention, as shown in FIG. 2, a reaction system using a high temperature and high pressure microreactor is exemplified as a suitable system, but a system having the same effect as this can be similarly used. . Here, the reaction system includes a high-temperature high-pressure microreactor, a reaction section composed of a reaction tube, and an oven facility for accommodating the high-temperature high-pressure water and a raw material aqueous solution such as lactic acid in a mixing means. Thermocouple to control the conditions to a predetermined temperature, a reaction tube, a cooler (heat exchanger) for cooling the reaction liquid reacted under high temperature and high pressure water conditions to a predetermined temperature, and depressurizing after cooling. It is equipped with a back pressure valve for

  It is carried out in high-temperature high-pressure water containing supercritical water having a reaction temperature of 200 ° C. to 500 ° C. and 10 MPa to 50 MPa shown in FIG. 2, preferably a temperature of 300 ° C. to 420 ° C., a pressure of 30 MPa to 50 MPa, and more preferably 320. When the reaction is carried out in the range of ℃ to 420 ℃ and pressure of 35 MPa to 45 MPa, the desired product can be obtained in good yield.

  In this reaction, the reaction time varies depending on the concentration of each raw material and the reaction rate, but by performing the reaction for 0.1 seconds to 10 minutes on average, the target product can be obtained with almost the maximum yield. However, the reaction can be carried out more preferably for 1 second or more and 5 minutes or less, and most preferably for 1 second or more and 1 minute or less, whereby the target product can be obtained while suppressing overreaction.

  This reaction selectively performs the dehydration process in high temperature and high pressure water in the presence of a metal (excluding austenitic stainless steel, nickel chrome molybdenum alloy, nickel chrome iron niobium alloy, brass). An α, β-unsaturated carboxylic acid can be obtained, in which case aluminum, silicon, titanium, vanadium, iron, nickel, copper, zinc, zirconium, molybdenum, ruthenium, rhodium, palladium, silver, tantalum, tungsten, The target can be selectively obtained by using one kind of metal selected from rhenium, iridium, platinum, gold and lead, or an alloy containing two or more kinds, but more preferably gold and silver. Selective by using a metal selected from at least one of copper, copper, iron, nickel and zinc, or an alloy containing them. Get it can be.

  The metal used in this reaction can be used in either a flow type or a batch type, and in the usual form, in order to have heat resistance and pressure resistance, for example, as a reaction tube of FIG. Alloy), Hastelloy C276 (nickel alloy) or SUS316 (stainless steel) tube, and can be used in the form of particles, wires, or tubes. If it is granular, the diameter is 1 μm or more. In the case of wire-like particles having a particle size of up to 5 mm, the length is not particularly limited, but one wire having a diameter of 1 μm or more and 5 mm or less and a length of 1 cm or more may be used, or a plurality of wires may be bundled and randomly packed. If it is a tube, one tube with an inner diameter of 0.1 mm to 5 mm may be used, or by bundling multiple tubes, the target product can be selectively obtained.In this case, the outer diameter, inner diameter, length, etc. of the reaction tube can be appropriately designed in carrying out the operation, and the material, outer diameter, inner diameter, and length for imparting heat resistance and pressure resistance to the reaction tube. The condition for the height can also be set as appropriate.

In the present invention, the starting material 2-hydroxycarboxylic acid or 2-hydroxycarboxylic acid ester is a compound represented by the following general formula (I) (wherein R ₁ and R ₂ are each independently hydrogen or an alkyl group). , Cycloalkyl group, vinyl group, aryl group such as phenyl group, nitrogen-containing heteroaryl group, amino group (-NR'R "), hydroxyl group, thiol group, alkoxy group (-OR), thioalkoxy group (- S-R), aldehyde group, carboxy group, alkylcarbonyl group (-C (O) R), alkyl ester group (-C (O) OR), alkylamide (-C (O) NR'R "), benzyl group, a halogen (F, Cl, Br, I ), a phosphonyl group (-P (O) (OR) 2), a cyano group, a sulfonyl group _{(-S (O) 2 R)} , a sulfinyl group (-S (O) R) represents one species (in the above formula, R ′ and R ″ each independently represent hydrogen or an alkyl group, R represents an alkyl group), and R ₃ represents hydrogen or alkyl. Group, a cycloalkyl group, a vinyl group, an aryl group, and an amino group are shown), an α, β-unsaturated carboxylic acid can be preferably obtained, but more preferably , Lactic acid, methyl lactate, ethyl lactate, propyl lactate, 2-hydroxyisobutyric acid, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, propyl 2-hydroxyisobutyrate, the desired acrylic acid, It is possible to obtain α, β-unsaturated carboxylic acids such as acrylic acid ester, methacrylic acid, and methacrylic acid ester or derivatives thereof.

  The acidity of the reaction solution can suitably synthesize the target product at any acidity, but considering the elution and corrosion of the metal used during the reaction, if the acidity is in the range of pH 5 to 10, the target product is preferably obtained. It is possible to obtain the desired product in good yield, and it is most preferable to obtain the desired product if it is carried out in the range of pH 6-8 near neutrality. It is not preferable to carry out the reaction under strong acidity, because the metal elutes significantly under strong acidity and the elution rate increases especially at high temperature and high pressure.

  Next, the present invention will be specifically described based on Examples and Comparative Examples, but the present invention is not limited to the following Examples.

<Example 1> [Synthesis 1 of acrylic acid from lactic acid]
The reaction was carried out using a general high temperature high pressure microreaction system. FIG. 2 shows the reaction part of the high temperature and high pressure micro reaction system. The reaction was carried out using a 10 m long double pipe (FIG. 3) in which a copper pipe having an inner diameter of 0.5 mm was lined inside a SUS316 pipe having an outer diameter of 1/8 inch.

  Lactic acid was used as a raw material for 2-hydroxycarboxylic acid, and acrylic acid was used as an α, β-unsaturated carboxylic acid for the reaction. Aqueous lactic acid solution (0.1 M, 0.5 mL / min) is quickly mixed with high-temperature and high-pressure water (distilled water or ion-exchanged water, 2.0 mL / min) with a micromixer, and the temperature is changed from room temperature (25 ° C) to a predetermined temperature. The temperature was rapidly raised to (300, 320, 340, 360, 380, each temperature of 400 ° C., 420, and pressure of 40 MPa). The temperature after heating was observed with a thermocouple, and the temperature of the oven was adjusted so that the temperature difference between the inlet and the outlet was less than 0.1 ° C. After mixing and heating to cause reaction in a reaction tube under high temperature and high pressure conditions, the mixture was cooled to a predetermined temperature (40 ° C.) with a cooler (heat exchanger), and finally depressurized via a back pressure valve. The reaction time is converted from the density of water to 300 ° C for 46.8 seconds, 320 ° C for 44.7 seconds, 360 ° C for 39.7 seconds, 380 ° C for 36.4 seconds, and 400 ° C for 32.0 seconds. Second was 25.9 seconds at 420 ° C. The obtained sample was a transparent aqueous solution, and the analysis was performed without further treatment by liquid chromatography and gas chromatography (GC) as an aqueous solution to analyze the product.

  FIG. 4 shows a GC chart of the obtained sample (reaction temperature 380 ° C., reaction pressure 40 MPa, reaction time 36.4 seconds). The product was detected using HP-INNOWAX as a column and an FID detector as a detector. The compound identification of each peak was determined from GC-MS and a standard sample, and the yield of each compound was determined by preparing a calibration curve using the standard sample.

  In FIG. 5, the yields of acrylic acid, hydroxyacetone, acetic acid, propionic acid, acetaldehyde, and 3-methyl-2 (5H) -furanone were calculated and shown in the graph at each temperature. It was found that at 40 MPa, there was a maximum value at 360 ° C. to 380 ° C., and it was found that the yield of acrylic acid was the highest at 85%. At the same time, it was also found that the yield of acetaldehyde was reduced to 10%. In all cases, including Examples 2 to 5 below, the raw material lactic acid did not remain, and the conversion rate was 100%. Therefore, in Examples 1 to 5, the numerical values of selectivity and yield were the same.

<Example 2> [Synthesis of acrylic acid from lactic acid 2-Investigation of influence of shape of copper]
As shown in FIG. 6 and FIG. 7, acrylic acid was synthesized under the same conditions as in Example 1 except that a reaction tube in which a copper wire was enclosed over the entire length of the reaction section in the SUS316 pipe was used. As a result, in each reaction tube, it was found that the yield of acrylic acid was 80% or more at around 380 ° C.
The conditions for the copper wire and the SUS316 pipe were as follows, and the reaction part internal volume excluding the copper wire volume was set to be substantially constant in all examples.
[Copper wire]
6- (a): diameter 2.0 mm, (b): diameter 1.6 mm, (c): diameter 1.2 mm, (d): diameter 0.25 mm, in FIGS. 6- (a)-(d) , A long wire extending in the tube axial direction over the entire length of the reaction section. Figure 7: Irregularly arranged copper wires with a diameter of 0.35 mm and a length of 2.57 mm.
[Made of SUS316]
6- (a) to 6- (c), the outer diameter is 1/4 inch and the inner diameter is 4.3 mm.
Figure 6- (d) shows an outer diameter of 1/8 inch and an inner diameter of 1.78 mm.
FIG. 7 has an outer diameter of 1/4 inch and an inner diameter of 4.3 mm.

<Example 3> [Synthesis of acrylic acid ester from lactate ester]
A synthetic reaction of ethyl acrylate was performed under the same conditions as in Example 1 except that ethyl lactate was used as a raw material. FIG. 8 shows the yields of acrylic acid, hydroxyacetone, acetic acid, propionic acid, acetaldehyde, and 3-methyl-2 (5H) -furanone, which are the produced compounds at each reaction temperature (300 to 420 ° C.). It was Although ethyl acrylate was hydrolyzed into acrylic acid, it was found that the yield of acrylic acid was as high as 83% at 40 MPa and 380 ° C.

<Example 4> [Synthesis of acrylic acid amide from lactamide]
A synthetic reaction of acrylic acid amide was performed under the same conditions as in Example 1 except that lactic acid amide was used as a raw material. As a result, it was found that acrylamide was obtained at a high yield of 90% or higher at 40 MPa and 380 ° C.

<Example 5> [Synthesis of acrylic acid from lactic acid 3-Investigation of influence of metal type]
Acrylic acid was synthesized under the same conditions as in Example 1 except that gold, silver, platinum, palladium, or titanium was used instead of copper. As a result, acrylic acid was 65%, 80%, 72%, 50% and 44%, respectively. Copper is most preferred, but it has been found that gold, silver, platinum, palladium and titanium also have the same effect of increasing the reaction efficiency.

<Comparative Example 1> [Synthesis of acrylic acid from lactic acid 4-Investigation of influence of alloy type 1]
Acrylic acid was synthesized under the same conditions as in Example 1 except that SUS316, Hastelloy (registered trademark) C-276, or Inconel 625 alloy system was used as the material of the reaction tube. As a result, it was found that the yield of acrylic acid remained at a maximum of about 14% in any of the alloys, which was not very effective. When SUS316 was used, the breakdown of the products at 400 ° C. and 40 MPa was as follows: acetaldehyde 49%, hydroxyacetone 1.5%, acetic acid 8.2%, propionic acid 29%, acrylic acid 7. It was found that the main products were by-products other than acrylic acid, especially propionic acid and acetaldehyde, with 9% and 4.2% for others (furanone, etc.).

<Comparative Example 2> [Synthesis of acrylic acid from lactic acid 5-investigation of influence of alloy type 2]
Acrylic acid was synthesized under the same conditions as in Example 1 except that a reaction tube having a brass (C2680) lined inside the SUS316 tube was used. In the case of brass, the maximum yield was 1.4%, and it was found that the alloy composed of copper and zinc was not so effective.

<Comparative Example 3> [Synthesis of acrylic acid from lactic acid 6-Investigation of influence of use of oxide]
Under the same conditions as in Example 1, a reaction tube made of SUS316 was filled with alumina, zirconia, or titania particles (particle size: 0.1 mm) to carry out the reaction, but the yield of acrylic acid was 3% at maximum. , Turned out to be ineffective.

  As described above in detail, the present invention relates to a method for synthesizing acrylic acid by treating lactic acid with high-temperature and high-pressure treatment water, wherein a metal such as copper during the reaction (however, austenitic stainless steel, nickel chrome molybdenum alloy, nickel (Excluding chrome iron niobium alloys and brass) in the reaction system, the selectivity / yield of acrylic acid was increased from 40% to 50% to 50% or more or 80% or more. It became possible to do. Moreover, since the medium is only water, it is environmentally friendly and has industrial applicability.

Claims (10)

In a reaction for obtaining an α, β-unsaturated carboxylic acid and / or a derivative thereof from a 2-hydroxycarboxylic acid and / or a derivative thereof, a metal (however, austenitic stainless steel is used) in high-temperature high-pressure water at 200 ° C. to 500 ° C. and 10 MPa to 50 MPa. Steel, nickel-chromium-molybdenum-based alloy, nickel-chromium-iron-niobium-based alloy, brass , or L-type zeolite, except modified L-type zeolite .), 2-hydroxycarboxylic acid and / or A method for producing an α, β-unsaturated carboxylic acid and / or a derivative thereof from the derivative.   The metal is selected from aluminum, silicon, titanium, vanadium, iron, nickel, copper, zinc, zirconium, molybdenum, ruthenium, rhodium, palladium, silver, tantalum, tungsten, rhenium, iridium, platinum, gold, lead 1 The manufacturing method according to claim 1, which is a metal of one kind or an alloy containing two or more kinds.   The said metal is a particle, a wire, or the shape of a pipe | tube, The manufacturing method of Claim 1 or 2 characterized by the above-mentioned.   The manufacturing method according to claim 3, wherein the tube has an inner diameter of 0.1 mm or more and 5 mm or less.   The manufacturing method according to claim 3, wherein the wire has a diameter of 1 μm or more and 5 mm or less and a length of 1 cm or more.   The manufacturing method according to claim 3, wherein the particles have a diameter of 1 μm or more and 5 mm or less.   The 2-hydroxycarboxylic acid and / or its derivative is 2-hydroxycarboxylic acid, 2-hydroxycarboxylic acid ester, 2-hydroxycarboxylic acid amide, and / or 2-hydroxycarboxylic acid thioester. The manufacturing method according to any one of 1. The 2-hydroxycarboxylic acid and / or the 2-hydroxycarboxylic acid ester is a compound represented by the general formula (I) (wherein R ₁ and R ₂ are each independently hydrogen, an alkyl group, a cyclohexyl group). Alkyl group, vinyl group, aryl group such as phenyl group, nitrogen-containing heteroaryl group, amino group (-NR'R "), hydroxyl group, thiol group, alkoxy group (-OR), thioalkoxy group (-S- R), aldehyde group, carboxy group, alkylcarbonyl group (—C (O) R), alkyl ester group (—C (O) OR), alkylamide (—C (O) NR′R ″), benzyl group, halogen (F, Cl, Br, I ), a phosphonyl group (-P (O) (OR) 2), a cyano group, a sulfonyl group _{(-S (O) 2 R)} , a sulfinyl group (-S (O) R) R 1 and R 3 each independently represent hydrogen or an alkyl group, and R represents an alkyl group; R ₃ represents hydrogen or an alkyl group; It represents one kind selected from a cycloalkyl group, a vinyl group, an aryl group, and an amino group.), The production method according to claim 7.

  The 2-hydroxycarboxylic acid and / or its derivative is lactic acid, methyl lactate, ethyl lactate, propyl lactate, 2-hydroxyisobutyric acid, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, propyl 2-hydroxyisobutyrate. , Lactic acid amide, N, N-dimethyl lactic acid amide, and / or lactic acid thioester, and α, β-unsaturated carboxylic acid and / or its derivative are acrylic acid, acrylic acid ester, methacrylic acid, methacrylic acid ester, Acrylamide, dimethylacrylamide, and / or acrylic acid thioester, The manufacturing method of any one of Claims 1-8 characterized by the above-mentioned.   The said 2-hydroxy carboxylic acid and / or its derivative (s) are lactic acid, a lactic acid ester, and / or a lactic acid amide, The manufacturing method of any one of Claims 1-9 characterized by the above-mentioned.

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