Method for chemical recycling of epoxy resin by catalytic hydrogenolysis

Abstract

To develop a technique that performs hydrogenolysis of epoxy resins under gentle conditions by means of a recoverable and reusable heterogeneous catalyst, thereby enabling selective recovery of phenols from the epoxy resins.SOLUTION: A catalyst comprises: a metal oxide carrier; a first metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper, supported on the carrier; and a second metal selected from platinum group elements, supported on the carrier. The catalyst is used for the hydrogenolysis of an epoxy resin. The epoxy resin may be cured.

Description

[Technical field]

[0001] The present invention relates to a novel catalyst for use in the hydrolysis of epoxy resins, and a method for hydrolysis of epoxy resins using said catalyst. [Background technology]

[0002] Conventional methods for decomposing epoxy resins have mainly been studied, such as thermal decomposition under high temperature (>250°C) or high pressure (>10 atm) conditions, and solvolysis under relatively mild conditions using a base. However, since the main purpose of decomposing epoxy resin is to recover the carbon fibers, glass fibers, and other components that make up the composite material, it is necessary to develop a technology for selectively recovering phenols from epoxy resin, but such a technology has not yet been established.

[0003] Recently, a decomposition reaction of epoxy resin by transfer hydrogenation using a homogeneous catalyst has been reported (Non-Patent Document 1). In addition, the inventors' laboratory has been conducting a decomposition reaction of epoxy resin by transfer hydrogenation using a homogeneous Ni catalyst. They developed a hydrogenolysis reaction of epoxy resin (Non-Patent Document 2). However, in these methods for decomposing epoxy resins, it is difficult to recover and reuse the catalyst because a homogeneous catalyst is used. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Nature 2023, 617, 730-737 [Non-Patent Document 2] ChemRxiv 2023 (preprint) 10.26434 / chemrxiv-2023-dz9v9-v2 DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0005] The object of the present invention is to develop a technique for selectively recovering phenols from an epoxy resin by subjecting the epoxy resin to a hydrogenolysis reaction (hydrocracking) under mild conditions using a heterogeneous catalyst that can be recovered and reused. Another object of the present invention is to enable the recovery of carbon fibers, glass fibers, etc. that constitute the composite material by such a technique.

Means for Solving the Problems

[0006] As a result of intensive studies aimed at solving the above problems, the present inventors have found that an epoxy resin can be effectively hydrocracked by a heterogeneous catalyst in which a metal selected from specific 3d transition metals and platinum group elements is supported on a metal oxide carrier, and have completed the present invention.

[0007] That is, the present invention has the following configuration. [1] A metal oxide carrier, At least one first metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper supported on the carrier, and A second metal selected from platinum group elements supported on the carrier A catalyst containing, Used for the hydrocracking of an epoxy resin, and the epoxy resin may be cured, the catalyst. [2] The catalyst according to [1], wherein the second metal is selected from platinum, palladium, rhodium, iridium, or ruthenium. [3] The catalyst according to [1] or [2], wherein the first metal is nickel. [4] The catalyst according to any one of [1] to [3], wherein the metal oxide carrier is aluminum oxide (Al2O3), titanium oxide (TiO2), zirconium oxide (ZrO2), or cerium oxide (CeO2). [5] The catalyst according to [4], wherein the metal oxide carrier is cerium oxide (CeO2). [6] The catalyst according to any one of [1] to [5], wherein the supported amount of the first metal is 0.01 to 0.50 mmol / g. [7] The catalyst according to any one of [1] to [6], wherein the supported amount of the second metal is 0.01 to 0.5 mmol / g. [8] The catalyst according to any one of [1] to [7], wherein the molar ratio of the second metal to the first metal is 0.01 to 100. [9] A method for using the catalyst according to any one of [1] to [8] in the hydrocracking of an epoxy resin.

[10] A metal oxide carrier At least one first metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper supported on the carrier, and A second metal selected from the platinum group elements supported on the carrier A catalyst containing By using A method for preparing phenols by hydrocracking an epoxy resin which may be cured.

[11] The method according to

[10] , wherein the phenols are any one or more of the following Compounds 1 to 3. TIFF2025089951000001.tif29158

[12] The method according to

[10] or

[11] , wherein as the phenols, Compound 1 and / or any one or more of Compounds 2 and 3 can be obtained.

[13] To a composite material containing a cured or uncured epoxy resin and fibers, A metal oxide carrier At least one first metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper supported on the carrier, and A second metal selected from the platinum group elements supported on the carrier A catalyst containing A method for recovering fibers from a composite material by using the catalyst to hydrocrack the epoxy resin.

[14] The method according to

[13] , wherein the fiber is one or more fibers selected from the group consisting of glass fiber, carbon fiber, ceramic fiber, aramid fiber, boron fiber, silica fiber, metal fiber, mineral fiber, rock fiber, and slag fiber.

Advantages of the Invention

[0008] By using the catalyst of the present invention, epoxy resin can be hydrocracked at a relatively low temperature (about 150 to 200 °C) using atmospheric pressure hydrogen, and phenols can be recovered in a high yield. Since the catalyst of the present invention is a heterogeneous catalyst, it can be recovered and reused. In addition, by using the catalyst of the present invention, a composite material containing an epoxy resin (part or all of which may be cured) and fibers can be hydrocracked, whereby the fibers contained in the composite material can be recovered.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0010] The present invention will be described in detail below. However, the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist thereof. In the present specification, when the expression "~" is used, it is used as an expression including the numerical values or physical property values before and after it.

[0011] 1. Catalyst of the present invention One embodiment of the present invention is a catalyst containing a metal oxide carrier, at least one first metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper supported on the carrier, and a second metal selected from platinum group elements supported on the carrier and is used for the hydrocracking of epoxy resin (hereinafter also referred to as "the catalyst of the present invention").

[0012] For the catalyst of the present invention, it is important to support a combination of metals selected from specific 3d transition metals and platinum group elements on a metal oxide support. Although not intended to be bound by theory, the active component of the 3d transition metal in the catalyst of the present invention is usually in the state of a cation having a positive charge (for example, a divalent cation in the case of Ni), but when exposed to a hydrogen atmosphere in a state supported on a metal oxide support such as cerium oxide (ceria), it becomes a zero-valent state, and it is considered that the 3d transition metal can be brought into a state necessary for the hydrogenolysis of epoxy resin.

[0013] In the catalyst of the present invention, the first metal is at least one selected from the group consisting of manganese, iron, cobalt, nickel and copper. Preferably, the first metal is nickel.

[0014] In the catalyst of the present invention, the second metal is selected from platinum group elements, preferably selected from platinum, palladium or ruthenium, and more preferably palladium. These platinum group elements can activate molecular hydrogen even under low temperature and normal pressure conditions, and can provide active hydrogen species necessary for the reduction of the carbon-oxygen bond of epoxy resin. In addition, nickel is induced into the zero-valent state necessary for the hydrogenolysis of epoxy resin.

[0015] The metal oxide support is, for example, aluminum oxide (Al2O3), titanium oxide (TiO2), zirconium oxide (ZrO2), cerium oxide (CeO2), and preferably cerium oxide (CeO2) having redox ability.

[0016] The supported amount of the first metal is preferably 0.01 to 0.5 mmol / g, and more preferably 0.1 to 0.5 mmol / g. When the supported amount of the first metal is within this range, the corresponding phenols can be obtained in a high yield by the decomposition of epoxy resin.

[0017] The supported amount of the second metal is preferably 0.01 to 0.5 mmol / g, more preferably 0.2 to 0.5 mmol / g. When the supported amount of the second metal is within this range, the corresponding phenols can be obtained in a high yield by the decomposition of the epoxy resin.

[0018] The molar ratio of the second metal to the first metal is preferably 0.01 to 100, more preferably 0.1 to 10. When the molar ratio of the second metal to the first metal is within this range, the corresponding phenols can be obtained in a high yield by the decomposition of the epoxy resin.

[0019] The catalyst of the present invention includes (1) a catalyst formed by obtaining a catalyst in which the first metal is supported on a metal oxide support and a catalyst in which the second metal is supported on a metal oxide support, and then combining them together (for example, mixing both), (2) a catalyst in which a combination of the first metal and the second metal is supported on a metal oxide support, and a combination of both. In the present invention, the catalyst may be any of the catalysts in the above (1) and (2) embodiments, but the embodiment (2) is preferred. Since the first metal and the second metal are present together on the support, the second metal can effectively induce the first metal to be in the zero-valent state necessary for the hydrogenolysis of the epoxy resin.

[0020] In the case of the above embodiment (2), the combination of the first metal and the second metal may exist as an alloy (for example, a solid solution, eutectic or intermetallic compound) on the support of each metal oxide support, or the first metal and the second metal may exist independently on each metal oxide support. Further, in the case of the embodiment (2), it may include a catalyst in which the first metal is supported on a metal oxide support and a catalyst in which the second metal is supported on a metal oxide support. In addition, the catalyst of the present invention may contain a first metal not supported on a metal oxide support and a second metal not supported on a metal oxide support within the range where the effects of the present invention are exhibited.

[0021] The particle size of the metal oxide serving as the carrier is not particularly limited, and any metal oxide generally used in catalysts or the like can be arbitrarily used.

[0022] The catalyst of the present invention is obtained by adding a metal oxide carrier such as cerium oxide (CeO2) to an aqueous solution of a salt of a first metal (for example, a halide (preferably a chloride), a nitrate), a salt of a second metal (for example, a halide (preferably a chloride), a nitrate), and an excessive amount (2 to 3 equivalents) of a salt (for example, a halide (such as a chloride) of potassium or the like) with respect to the concentration of the salt of the second metal, adjusting the pH with an aqueous solution of a base such as sodium hydroxide (for example, pH = 9 to 11), stirring at room temperature or the like for a predetermined time, and then filtering the solid. It can be obtained by washing with water and drying.

[0023] The catalyst of the present invention can be used for the hydrocracking of epoxy resins. As the epoxy resin, the catalyst of the present invention can be used for various epoxy resins. As an example, the catalyst of the present invention can be used for a general epoxy resin represented by the following formula (2), but is not limited thereto.

[0024] TIFF2025089951000002.tif30156

[0025] In formula (2), R is an amino group (including a substituted or unsubstituted primary alkylamino group, a substituted or unsubstituted secondary alkylamino group), an ammonium salt (including a substituted or unsubstituted alkylammonium salt), an ester group, or the like. Also, n is the degree of polymerization (usually about 1 to 5, but not limited thereto).

[0026] The catalyst of the present invention can be used for a partially or wholly cured or crosslinked epoxy resin, and can also be used for an epoxy resin cured with an acid anhydride, an epoxy resin cured with an aliphatic amine, an epoxy resin cured with an aromatic amine, and the like. Non-limiting examples of epoxy resins cured with acid anhydrides, epoxy resins cured with aliphatic amines, and epoxy resins cured with aromatic amines are shown below.

[0027] (Non-limiting examples of anhydride-cured epoxy resins) TIFF2025089951000003.tif39154 (Non-limiting examples of aliphatic amine-cured epoxy resins) TIFF2025089951000004.tif59154 (Non-limiting examples of aromatic amine-cured epoxy resins) TIFF2025089951000005.tif46160 (Non-limiting examples of aromatic amine-cured epoxy resins) TIFF2025089951000006.tif45148

[0028] By performing the hydrogenolysis reaction of the epoxy resin using the catalyst of the present invention, the conversion rate of the epoxy resin can be preferably 20% or more, more preferably 30% or more, still more preferably 40% or more, particularly preferably 50% or more, and especially preferably 80% or more for the hydrogenolysis reaction.

[0029] By performing the hydrogenolysis reaction of the epoxy resin using the catalyst of the present invention, bisphenol A (Compound 1 below), phenols (Compounds 2 and 3 below) can be obtained. TIFF2025089951000007.tif26157

[0030] By performing the hydrogenolysis reaction of the epoxy resin using the catalyst of the present invention, preferably, one or more of the following Compounds 1 to 3 can be obtained. Which of the Compounds 1 to 3 is preferentially produced varies depending on the type of the catalyst or base of the present invention, the type of the epoxy resin, etc., but more preferably, Compound 1 and / or one or more of Compounds 2 and 3 can be obtained.

[0031] In one preferred embodiment of the present invention, by performing the hydrocracking reaction of the epoxy resin using the catalyst of the present invention, Compound 1 can be preferably obtained in a yield of 10% or more, more preferably 20% or more, still more preferably 30% or more, and particularly preferably 50% or more. In another preferred embodiment of the present invention, by performing the hydrocracking reaction of the epoxy resin using the catalyst of the present invention, one or more of Compounds 2 and 3 can be preferably obtained in a yield of 10% or more, more preferably 20% or more, still more preferably 30% or more, and particularly preferably 50% or more.

[0032] When using the catalyst of the present invention for the hydrocracking reaction of the epoxy resin, the reaction can be carried out at a low temperature (less than 150 to 250 °C) using normal pressure hydrogen.

[0033] As described above, the catalyst of the present invention can selectively recover phenols from the epoxy resin. Further, since the catalyst of the present invention is a heterogeneous catalyst, it can be recovered and reused.

[0034] 2. Preparation of phenols by hydrocracking reaction Another embodiment of the present invention is a method for preparing phenols by hydrocracking an epoxy resin using a catalyst containing a metal oxide support, at least one first metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper supported on the support, and a second metal selected from platinum group elements supported on the support (hereinafter also referred to as "the preparation method of the present invention"). By the preparation method of the present invention, the epoxy resin can be hydrocracked at a relatively low temperature (less than 150 to 250 °C) using normal pressure hydrogen to recover phenols in a high yield. The catalyst used in the preparation method of the present invention is as described in detail in the catalyst of the present invention.

[0035] The catalyst used in the preparation method of the present invention is as described in detail in the catalyst of the present invention.

[0036] In the preparation method of the present invention, the first metal of the catalyst is at least one selected from the group consisting of manganese, iron, cobalt, nickel and copper. Preferably, the first metal is nickel.

[0037] In the preparation method of the present invention, the second metal of the catalyst is selected from platinum group elements, preferably selected from platinum, palladium or ruthenium, and more preferably palladium.

[0038] In the preparation method of the present invention, the metal oxide carrier of the catalyst is, for example, aluminum oxide (Al2O3), titanium oxide (TiO2), zirconium oxide (ZrO2), cerium oxide (CeO2), and preferably cerium oxide (CeO2).

[0039] In the preparation method of the present invention, the loading amount of the first metal in the catalyst is preferably 0.01 to 0.5 mmol / g, and more preferably 0.1 to 0.5 mmol / g.

[0040] In the preparation method of the present invention, the loading amount of the second metal in the catalyst is preferably 0.01 to 0.5 mmol / g, and more preferably 0.2 to 0.5 mmol / g.

[0041] In the preparation method of the present invention, the molar ratio of the second metal to the first metal in the catalyst is preferably 0.01 to 100, and more preferably 0.1 to 10.

[0042] In the preparation method of the present invention, phenols are obtained by hydrocracking the carbon-oxygen bond of the epoxy resin. The epoxy resin that can be used in the preparation method of the present invention is as detailed in the catalyst of the present invention. As an example, in the preparation method of the present invention, it can be used for a general epoxy resin represented by the following formula (2), but is not limited thereto.

[0043] TIFF2025089951000008.tif30166

[0044] In formula (2), R is an amino group (including a substituted or unsubstituted primary alkylamino group, a substituted or unsubstituted secondary alkylamino group), an ammonium salt (including a substituted or unsubstituted alkylammonium salt), an ester group, or the like. Also, n is the degree of polymerization (usually about 1 to 5, but not limited thereto).

[0045] In addition, the epoxy resin that can be used in the preparation method of the present invention can be used for a partially or entirely cured epoxy resin, and can be used for an epoxy resin cured with an anhydride (for example, the anhydride-cured epoxy resin represented by the above formula (A)), an epoxy resin cured with an aliphatic amine (for example, the aliphatic amine-cured epoxy resin represented by the above formula (B)), an epoxy resin cured with an aromatic amine (for example, the aromatic amine-cured epoxy resins represented by the above formulas (C) and (D)), etc.

[0046] In the preparation method of the present invention, the phenols are preferably any one or more of the following Compounds 1 to 3. TIFF2025089951000009.tif30163

[0047] Which of Compounds 1 to 3 is preferentially produced varies depending on the type of catalyst or base of the present invention, the type of epoxy resin, etc., but in the preparation method of the present invention, more preferably, as the phenols, one or more of Compound 1 and / or Compound 2 and 3 can be obtained.

[0048] In the preparation method of the present invention, the reaction can be carried out at a low temperature (less than 150 to 250 °C) using normal pressure hydrogen.

[0049] The preparation method of the present invention usually adds the catalyst and epoxy resin of the present invention to a solvent and carries out the reaction under a normal pressure hydrogen atmosphere. As the solvent, for example, N-methylpyrrolidone, N,N-dimethylacetamide are used. In addition, in the preparation method of the present invention, the catalyst of the present invention can be pretreated and then added to the solvent. The pretreatment conditions are usually carried out at 150 to 300 °C for 0.5 to 3 hours. In addition, in order to further promote the decomposition of the epoxy resin, a base such as 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or potassium hexamethyldisilazide (KHMDS) may be added.

[0050] In the preparation method of the present invention, the hydrogenolysis reaction can be carried out with the conversion rate of the epoxy resin preferably being 20% or more, more preferably 30% or more, still more preferably 40% or more, particularly preferably 50% or more, and especially preferably 80% or more.

[0051] In one preferred embodiment of the preparation method of the present invention, Compound 1 can be obtained preferably with a yield of 10% or more, more preferably 20% or more, still more preferably 30% or more, particularly preferably 50% or more. In another preferred embodiment of the preparation method of the present invention, any one or more of Compounds 2 and 3 can be obtained preferably with a yield of 10% or more, more preferably 20% or more, still more preferably 30% or more, particularly preferably 50% or more.

[0052] 3. Method for recovering fibers from composite materials Another embodiment of the present invention is a method for recovering fibers from a composite material containing an epoxy resin that may be cured and fibers, a metal oxide carrier, at least one first metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper supported on the carrier, and a second metal selected from platinum group elements supported on the carrier by using a catalyst containing the above to hydrogenolyze the epoxy resin (hereinafter also referred to as "the recovery method of the present invention").

[0053] Epoxy resins are commonly used in various applications as composites containing a cured product obtained by curing with a curing agent and fibers. By treating a composite material containing an epoxy resin and fibers using the catalyst of the present invention, the epoxy resin can be hydrocracked, and thereby, the fibers contained in the composite material can be recovered.

[0054] The epoxy resin contained in the composite material may be a general epoxy resin represented by formula (2) described in the preparation method of the present invention, but is not limited thereto. Also, the epoxy resin contained in the composite material may be a partially or fully cured epoxy resin. For example, it may be an epoxy resin cured with an acid anhydride, an epoxy resin cured with an amine, etc. Non-limiting examples of epoxy resins cured with acid anhydrides and epoxy resins cured with amines are as described in the preparation method of the present invention, but the epoxy resin contained in the composite material used in the recovery method of the present invention is not limited thereto.

[0055] Examples of the fibers contained in the composite material include various reinforcing fibers commonly used in composite materials. For example, they are one or more fibers selected from the group consisting of glass fibers, carbon fibers, ceramic fibers, aramid fibers, boron fibers, silica fibers, metal fibers, mineral fibers, rock fibers, and slag fibers.

[0056] Examples of the composite material containing an epoxy resin and fibers used in the recovery method of the present invention include substrates for electronic circuits, composite materials used in automobiles, airplanes, railway vehicles, etc., building materials, ships, aerospace, highly flame-retardant laminated composite materials used in electrical equipment and plastic pipes, etc., or fiber-reinforced composite materials (FRP) used in hydrogen stations for fuel cell vehicles, in-vehicle fuel tanks for CNG vehicles, fuel cell vehicles, etc., high-pressure gas containers for hydrogen gas storage, and epoxy resin composite materials used in wind turbine blades.

[0057] In the recovery method of the present invention, the first metal of the catalyst is at least one selected from the group consisting of manganese, iron, cobalt, nickel, and copper. Preferably, the first metal is nickel.

[0058] In the recovery method of the present invention, the second metal of the catalyst is selected from platinum group elements, preferably selected from platinum, palladium, or ruthenium, and more preferably palladium.

[0059] In the recovery method of the present invention, the metal oxide carrier of the catalyst is, for example, aluminum oxide (Al2O3), titanium oxide (TiO2), zirconium oxide (ZrO2), cerium oxide (CeO2), and preferably cerium oxide (CeO2).

[0060] In the recovery method of the present invention, the loading amount of the first metal in the catalyst is preferably 0.01 to 0.5 mmol / g, and more preferably 0.1 to 0.5 mmol / g.

[0061] In the preparation method of the present invention, the loading amount of the second metal in the catalyst is preferably 0.01 to 0.5 mmol / g, and more preferably 0.2 to 0.5 mmol / g.

[0062] In the recovery method of the present invention, the molar ratio of the second metal to the first metal in the catalyst is preferably 0.01 to 100, and more preferably 0.1 to 10.

[0063] In the recovery method of the present invention, the hydrogenolysis reaction of the epoxy resin can be carried out at a low temperature (less than 150 to 250 °C) using normal pressure hydrogen.

[0064] In the recovery method of the present invention, usually, the catalyst of the present invention, an optionally cured epoxy resin, and a composite material containing fibers are added to a solvent, and the reaction is carried out under a normal pressure hydrogen atmosphere. As the solvent, for example, N-methylpyrrolidone, N,N-dimethylacetamide are used. In addition, in the recovery method of the present invention, the catalyst of the present invention can be pretreated and then added to the solvent. The pretreatment conditions are usually carried out at 150 to 300 °C for 0.5 to 3 hours. In addition, in order to further promote the decomposition of the epoxy resin in the composite material, bases such as potassium phosphate (K3PO4) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) may be added.

Examples

[0065] Hereinafter, the examples and comparative examples of the present invention will be shown and specifically described. However, the present invention is not limited to these examples. The raw materials, measurement methods, and measuring instruments used in the following examples and comparative examples are as follows.

[0066] [Raw materials used] Glycidyl end-capped poly(Bisphenol A-co-epichlorohydrin) CeO2 was obtained from Sigma-Aldrich, and diethylamine, NiCl2, and PdCl2 were obtained from Tokyo Chemical Industry Co., Ltd. NaOH and KCl were obtained from Fujifilm Wako Pure Chemical Corporation. TiO2 (JRC-TIO-14), ZrO2 (JRC-ZRO-6), and Al2O3 (JRC-ALO-8) were obtained from the Reference Catalyst Subcommittee of the Catalysis Society of Japan.

[0067] [Measuring instruments] As the gas chromatograph (GC), Shimadzu GC-2014 equipped with a flame ionization detector (FID) was used. As the gas chromatograph-mass spectrometer (GC-MS), Shimadzu GCMS-QP2010 was used. As the nuclear magnetic resonance apparatus (NMR), BRUKER Ascend500 was used. The supported amounts of Ni, Pd, etc. were measured using Thermo Fisher Scientific iCAP PRO XP Duo (ICP-OES) after dissolving the supported metals with aqua regia. STEM-EDS was measured using a JEOL JEM-ARM 200F Thermal FE STE M.

[0068] [Synthesis Comparative Example 1] Preparation of Ni / CeO2 First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of NiCl2 (8.33 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain a Ni / CeO2 catalyst (1.9 g, Ni content: 0.21 mmol / g -1 , 1.3 wt%) (Sample No. 1).

[0069] [Synthesis Example 1] Ni1Pd 0.1 / CeO2 Preparation First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of NiCl2 (8.33 mM), PdCl2 (0.83 mM), and KCl (2 equivalents to PdCl2, 1.66 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain Ni1Pd 0.1 / CeO2 catalyst (1.9 g, Pd content: 0.026 mmol / g -1 , 0.28 wt%, Ni content: 0.23 mmol / g -1 , 1.3 wt%) (Sample No. 2).

[0070] [Synthesis Example 2] Ni1Pd 0.5 / CeO2 Preparation First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of NiCl2 (8.33 mM), PdCl2 (4.17 mM), and KCl (2 equivalents to PdCl2, 8.33 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain Ni1Pd 0.5 / CeO2 catalyst (1.9 g, Pd content: 0.13 mmol g -1 , 1.3 wt%, Ni content: 0.24 mmol g -1 , 1.4 wt%) (Sample No. 3).

[0071] [Synthesis Example 3] Preparation of Ni1Pd1 / CeO2 First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of NiCl2 (8.33 mM), PdCl2 (8.33 mM), and KCl (2 equivalents to PdCl2, 16.7 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain Ni1Pd1 / CeO2 catalyst (1.9 g, Pd content: 0.26 mmol g -1 , 2.8 wt%, Ni content: 0.21 mmol g -1 , 1.2 wt%) (Sample No. 4).

[0072] [Synthesis Example 4] Ni 0.5 Pd1 / CeO2 Preparation First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of NiCl2 (4.17 mM), PdCl2 (8.33 mM), and KCl (2 equivalents to PdCl2, 16.7 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain Ni 0.5 Pd1 / CeO2 catalyst (1.9 g, Pd content: 0.24 mmol g -1, 2.6 wt%, Ni content: 0.11 mmol / g -1 , 0.7 wt%) was obtained (Sample No. 5).

[0073] [Synthesis Example 5] Preparation of Ni2Pd1 / CeO2 First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of NiCl2 (16.7 mM), PdCl2 (8.33 mM), and KCl (2 equivalents to PdCl2, 16.7 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain a Ni2Pd1 / CeO2 catalyst (1.9 g, Pd content: 0.24 mmol / g -1 , 2.6 wt%, Ni content: 0.46 mmol / g -1 , 2.7 wt%) was obtained (Sample No. 6).

[0074] [Synthesis Comparative Example 2] Preparation of Pd / CeO2 First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of PdCl2 (8.33 mM) and KCl (2 equivalents to PdCl2, 16.7 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain a Pd / CeO2 catalyst (1.9 g, Pd content: 0.26 mmol / g -1 , 2.8 wt%) was obtained (Sample No. 7).

[0075] [Synthesis Example 6] Preparation of Ni1Pd1 / TiO2 First, TiO2 (2.0 g) was added to an aqueous solution (60 mL) of NiCl2 (8.33 mM), PdCl2 (8.33 mM), and KCl (2 equivalents to PdCl2, 16.7 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, it was adjusted to pH 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain a Ni1Pd1 / TiO2 catalyst (1.9 g, Pd content: 0.24 mmol g -1 , 2.6 wt%, Ni content: 0.20 mmol g -1 , 1.2 wt%) (Sample No. 8).

[0076] [Synthesis Example 7] Preparation of Ni1Pd1 / Al2O3 First, Al2O3 (2.0 g) was added to an aqueous solution (60 mL) of NiCl2 (8.33 mM), PdCl2 (8.33 mM), and KCl (2 equivalents to PdCl2, 16.7 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain a Ni1Pd1 / Al2O3 catalyst (1.9 g, Pd content: 0.24 mmol g -1 , 2.6 wt%, Ni content: 0.27 mmol g -1 , 1.6 wt%) (Sample No. 9).

[0077] [Synthesis Example 8] Preparation of Cu1Pd1 / CeO2 First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of CuCl2 (8.33 mM), PdCl2 (8.33 mM), and KCl (2 equivalents to PdCl2, 16.7 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain a Cu1Pd1 / CeO2 catalyst (1.9 g, Pd content: 0.25 mmol g -1 , 2.6 wt%, Ni content: 0.24 mmol g -1, (1.5 wt%) was obtained (Sample No. 10).

[0078] [Synthesis Example 9] Preparation of Co1Pd1 / CeO2 First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of CoCl2 (8.33 mM), PdCl2 (8.33 mM), and KCl (2 equivalents to PdCl2, 16.7 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain a Co1Pd1 / CeO2 catalyst (1.9 g, Pd content: 0.25 mmol g -1 , 2.7 wt%, Co content: 0.19 mmol g -1 , 1.1 wt%) (Sample No. 11).

[0079] [Synthesis Example 10] Preparation of Fe1Pd1 / CeO2 First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of FeCl3 (8.33 mM), PdCl2 (8.33 mM), and KCl (2 equivalents to PdCl2, 16.7 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain an Fe1Pd1 / CeO2 catalyst (1.9 g, Pd content: 0.24 mmol g -1 , 2.6 wt%, Ni content: 0.23 mmol g -1 , 1.3 wt%) (Sample No. 12).

[0080] [Synthesis Example 11] Preparation of Mn1Pd1 / CeO2 First, CeO2 (2.0 g) was added to an aqueous solution (60 mL) of MnCl2 (8.33 mM), PdCl2 (8.33 mM), and KCl (2 equivalents to PdCl2, 16.7 mM). After the resulting mixture was vigorously stirred at room temperature for 10 minutes, the pH was adjusted to 10 ± 0.5 using an aqueous NaOH solution (1 M). After vigorously stirring at room temperature for 24 hours, the solid was filtered, washed with water (2 L), and dried in vacuo to obtain a Mn1Pd1 / CeO2 catalyst (1.9 g, Pd content: 0.24 mmol g -1 , 2.6 wt%, Mn content: 0.25 mmol g -1 , 1.4 wt%) (Sample No. 13).

[0081] [Synthesis Example 12] Preparation of Ni1Pt1 / CeO2 First, CeO2 (2.0 g) was added to acetone (25 mL) of platinum(II) acetylacetonate (10.0 mM) and nickel(II) acetylacetonate (10.0 mM). After the resulting mixture was vigorously stirred at room temperature for 3 hours, the acetone was evaporated under vacuum. The obtained solid was calcined at 300 °C for 3 hours to obtain a Ni1Pt1 / CeO2 catalyst (0.9 g, Pt content: 0.19 mmol g -1 , 3.6 wt%, Mn content: 0.25 mmol g -1 , 1.5 wt%) (Sample No. 14).

[0082] [Synthesis Example 13] Preparation of Fe1Pt1 / CeO2 First, CeO2 (2.0 g) was added to acetone (25 mL) of platinum(II) acetylacetonate (10.0 mM) and iron(III) acetylacetonate (10.0 mM). After the resulting mixture was vigorously stirred at room temperature for 3 hours, the acetone was evaporated under vacuum. The obtained solid was calcined at 300 °C for 3 hours to obtain an Fe1Pt1 / CeO2 catalyst (0.9 g, Pt content : 0.18 mmol g -1 , 3.5 wt%, Mn content: 0.25 mmol g -1 , 1.4 wt%) (Sample No. 15).

[0083] [Example 1] Hydrocracking of amine-terminated epoxy resin prepolymer (1) Using Pd1Ni1 / CeO2 (catalyst sample 4) obtained in Synthesis Example 3, the hydrogenolysis of the amine-terminated epoxy resin prepolymer (1) represented by the following reaction scheme 1 was carried out under the following conditions.

[0084] (Scheme 1) TIFF2025089951000010.tif20161

[0085] The amine-terminated epoxy resin prepolymer 1 was synthesized by the following procedure. Glycidyl end-capped poly(Bisphenol A-co-epichlorohydrin) (10.0 g, 9.7 mmol), diethylamine (10 mL, 96.7 mmol), and a Teflon-coated stir bar were placed in a eggplant flask (50 mL) and stirred at 80 °C for 18 h. After completion of the reaction, the remaining diethylamine was distilled off using a rotary evaporator. Thereby, prepolymer 1 (9.6 g) was obtained.

[0086] Pd1Ni1 / CeO2 (100 mg) was added to a Schlenk tube (volume: about 25 mL) connected to a balloon filled with H2 (1 atm). Then, after pretreating the catalyst at 150 °C for 30 min, N-methylpyrrolidone (2.0 mL), amine-terminated epoxy resin prepolymer (1) (200 mg, 0.52 mmol BPA unit) and a Teflon-coated magnetic stir bar were sequentially added to the Schlenk tube under N2 atmosphere. The reaction mixture was degassed twice by the freeze-pump-thaw method and the Schlenk tube was connected to a balloon filled with H2. The reaction mixture was vigorously stirred at 180 °C for 12 h. After completion of the reaction, internal standard substances (1,1,2,2-tetrachloroethane and dodecane) were added to the reaction mixture. 1,1,2,2-Tetrachloroethane was used as the internal standard substance 1 for 1H NMR analysis Furthermore, the conversion rate of prepolymer 1 and the yield of compound 4 were determined, and the yields of compounds 2 and 3 were determined by GC analysis using dodecane as an internal standard substance.

[0087] Using catalyst samples 1 to 3, 5 to 17, experiments were carried out under the same conditions as above. The results are shown in Table 1. Note that catalyst sample 16 is a mixture of 0.1 g each of catalyst sample 1 and catalyst sample 7. Catalyst sample 16 is also within the scope of the catalyst of the present invention. In addition, for catalyst sample 17, the purchased CeO2 described above was used.

[0088]

Table 1

[0089] [Example 2] Hydrocracking of model compounds 5 to 8 Pd1Ni1 / CeO2 (100 mg) was added to a Schlenk tube (volume: about 25 mL) connected to a balloon filled with H2 (1 atm). Then, after pretreating the catalyst at 150 °C for 30 minutes, N-methylpyrrolidone (2.0 mL), model compounds (5 to 8) (0.25 mmol of 5 or 7, 0.50 mmol of 6 or 8), and a Teflon-coated magnetic stir bar were sequentially added to the Schlenk tube under a N2 atmosphere. The reaction mixture was degassed twice by the freeze-pump-thaw method and the Schlenk tube was connected to a balloon filled with H2 (1 atm). The reaction mixture was vigorously stirred at 180 °C for 9 hours. After the reaction was completed, internal standard substances (1,1,2,2-tetrachloroethane and dodecane) were added to the reaction mixture. Using 1,1,2,2-tetrachloroethane as the internal standard substance 1 The conversion rates of compounds 5 to 8 were determined by 1H NMR analysis, and the yield of compound 9 was determined by GC analysis using dodecane as the internal standard substance. standard substance.

[0090] The structural formulas and reaction schemes of compounds 5 to 8, and the results are shown below. The numbers indicated by (N2) represent the yields of compound 9 when the experiment was carried out with N2 (1 atm) instead of H2 (1 atm).

[0091] TIFF2025089951000012.tif96159

[0092] [Example 3] Catalyst reuse experiment After the hydrocracking of model compound 5, the catalyst was recovered by filtration (>92% recovery rate) and washed three times with acetone (50 mL), water (50 mL), and ethanol (50 mL). After drying at room temperature, the catalyst was treated at 300 °C for 1 h under 1 atm of H2. The regenerated catalyst was reused for the hydrogenolysis of model compound 1. This operation was repeated five times.

[0093] The results are shown in Figure 1. The left bar graph in each cycle of Figure 1a shows the conversion rate of model compound 5, and the right bar graph shows the yield of compound 9. The solid line in Figure 1b shows the time variation of the yield of compound 9 in the presence of the catalyst. The dotted line shows that when the catalyst is removed by filtration after the reaction has been carried out for 6 h, the progress of the reaction stops. These results support that the reaction proceeds on the catalyst surface and the catalyst acts as a heterogeneous catalyst.

[0094] [Example 4] Decomposition of acid anhydride-cured epoxy resin Pd1Ni1 / CeO2 (100 mg) was added to a Schlenk tube (volume: about 25 mL) connected to a balloon filled with H2 (1 atm). Then, the catalyst was pretreated at 300 °C for 1 h. After the pretreatment, N-methylpyrrolidone (2.0 mL), acid anhydride-cured epoxy resin (333.3 mg in 0.5 mmol BPA units), 1,8-diazabicyclo[5.4.0 Undeca-7-ene (DBU, 0.35 mmol) and a Teflon-coated magnetic stir bar were sequentially added to a Schlenk tube under an N2 atmosphere. The reaction mixture was degassed twice by the freeze-pump-thaw method and the Schlenk tube was connected to a balloon filled with H2 (1 atm). The reaction mixture was vigorously stirred at 180 °C for 72 h. After the reaction was completed, an internal standard substance (1,3,5-trimethylbenzene) was added to the reaction mixture. The reaction mixture was filtered and the obtained solid was dried under vacuum. The filtrate was analyzed by GC to determine the yield of bisphenol A.

[0095] The reaction scheme and results are shown below. The yield of bisphenol A by the hydrogenolysis of the acid anhydride-cured epoxy resin was 60%.

[0096] TIFF2025089951000013.tif48167

[0097] [Example 5] Decomposition of aliphatic amine-cured epoxy resin Pd1Ni1 / CeO2 (100 mg) was added to a Schlenk tube (volume: ca. 25 mL) connected to a balloon filled with H2 (1 atm). Then, the catalyst was pretreated at 300 °C for 1 h. After the pretreatment, N-methylpyrrolidone (2.0 mL), amine-cured epoxy resin (223 mg in 0.5 mmol BPA units), potassium hexamethyldisilazide (KHMD S, 0.5 mmol), and a Teflon-coated magnetic stir bar were sequentially added to the Schlenk tube under an N2 atmosphere. The reaction mixture was degassed twice by the freeze-pump-thaw method and the Schlenk tube was connected to a balloon filled with H2 (1 atm). The reaction mixture was vigorously stirred at 180 °C for 72 h. After the reaction was completed, an internal standard substance (1,3,5-trimethylbenzene) was added to the reaction mixture. The reaction mixture was filtered and the obtained solid was dried under vacuum. The filtrate was analyzed by GC to determine the yield of phenolic compounds.

[0098] The reaction scheme and results are shown below. The yields of phenolic compounds of Compounds 3 and 4 by the hydrogenolysis of the aliphatic amine-cured epoxy resin were >99%.

[0099] TIFF2025089951000014.tif47165

[0100] [Example 6] Decomposition of Aromatic Amine-Cured Epoxy Resin Pd1Ni1 / CeO2 (100 mg) was added to a Schlenk tube (volume: about 25 mL) connected to a balloon filled with H2 (1 atm). Then, the catalyst was pretreated at 300 °C for 1 hour. After the pretreatment, N-methylpyrrolidone (2.0 mL), amine-cured epoxy resin (295 mg in 0.5 mmol BPA units), potassium phosphate (K3PO4, 0.25 mm ol), and a Teflon-coated magnetic stir bar were sequentially added to the Schlenk tube under an N2 atmosphere. The reaction mixture was degassed twice by the freeze-pump-thaw method and the Schlenk tube was connected to a balloon filled with H2 (1 atm). The reaction mixture was vigorously stirred at 180 °C for 36 hours. After the reaction was completed, an internal standard substance (1,3,5-trimethylbenzene) was added to the reaction mixture. The reaction mixture was filtered and the obtained solid was dried under vacuum. The filtrate was analyzed by GC to determine the yield of phenolic compounds.

[0101] The reaction scheme and results are shown below. By the hydrogenolysis of the aromatic amine-cured epoxy resin, the yields of the phenolic compounds of Compounds 3 and 4 were 57% and 73%, respectively.

[0102] TIFF2025089951000015.tif35166

[0103] [Example 7] Decomposition of Aromatic Amine-Cured Epoxy Resin Pd1Ni1 / CeO2 (100 mg) was added to a Schlenk tube (volume: about 25 mL) connected to a balloon filled with H2 (1 atm). Then, the catalyst was pretreated at 300 °C for 1 hour. After the pretreatment, N-methylpyrrolidone (2.0 mL), amine-cured epoxy resin (269 mg in 0.5 mmol BPA units), potassium phosphate (K3PO4, 0.25 mm ol), and a Teflon-coated magnetic stir bar were sequentially added to a Schlenk tube under an N2 atmosphere. The reaction mixture was degassed twice by the freeze-pump-thaw method and connected to a balloon filled with H2 (1 atm). The reaction mixture was vigorously stirred at 180 °C for 36 h. After the reaction was completed, an internal standard substance (1,3,5-trimethylbenzene) was added to the reaction mixture. The reaction mixture was filtered, and the obtained solid was dried under vacuum. The filtrate was analyzed by GC to determine the yield of phenolic compounds.

[0104] The reaction scheme and results are shown below. By the hydrogenolysis of the aromatic amine-cured epoxy resin, the yields of the phenolic compounds of Compounds 3 and 4 were 72% and 29%, respectively.

[0105] TIFF2025089951000016.tif40164

[0106] [Example 8] Decomposition of Circuit Board (Glass Fiber Composite Material) Pd1Ni1 / CeO2 (100 mg) was added to a Schlenk tube (volume: about 25 mL) connected to a balloon filled with H2 (1 atm). Then, the catalyst was pretreated at 300 °C for 1 h. After the pretreatment, N-methylpyrrolidone (3.0 mL), a circuit board (1.08 g), potassium phosphate (0.2 mmol), and a Teflon-coated magnetic stir bar were sequentially added to the Schlenk tube under an N2 atmosphere. The reaction mixture was degassed twice by the freeze-pump-thaw method and connected to a balloon filled with H2 (1 atm). The reaction mixture was vigorously stirred at 180 °C for 72 h. After the reaction was completed, an internal standard substance (1,3,5-trimethylbenzene) was added to the reaction mixture. The reaction mixture was filtered, and the obtained solid was dried under vacuum. The filtrate was analyzed by GC to determine the yield of phenolic compounds. Note that the circuit board (glass fiber composite material) used was a KAUMO universal substrate (double-sided steel hole, base material: glass epoxy material).

[0107] The reaction scheme and results are shown in Figure 2. By the hydrogenolysis of the circuit board, 0.29 mmol of phenols, 305.6 mg of glass fiber, and 106.5 mg of metal material were obtained.

[0108] [Example 9] Decomposition of carbon fiber composite Pd1Ni1 / CeO2 (100 mg) was added to a Schlenk tube (volume: about 25 mL) connected to a balloon filled with H2 (1 atm). Then, the catalyst was pretreated at 300 °C for 1 hour. After the pretreatment, N-methylpyrrolidone (3.0 mL), carbon fiber composite (0.32 g), potassium phosphate (0.2 mmol), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU, 0.3 mmol), and a Teflon-coated magnetic stir bar were sequentially added to the Schlenk tube under an N2 atmosphere. The reaction mixture was degassed twice by the freeze-degas method and the Schlenk tube was connected to a balloon filled with H2 (1 atm). The reaction mixture was vigorously stirred at 180 °C for 72 hours. After the reaction was completed, an internal standard substance (1,3,5-trimethylbenzene) was added to the reaction mixture. The reaction mixture was filtered and the obtained solid was dried under vacuum. The filtrate was analyzed by GC to determine the yield of phenolic compounds. Note that an ARRIS 3K carbon plate sheet was used as the carbon fiber composite.

[0109] The reaction scheme and results are shown in Figure 3. By the decomposition of the carbon fiber composite, 0.27 mmol of phenols and 0.21 g of carbon fiber were obtained.

Claims

1. A metal oxide support, At least one first metal selected from the group consisting of manganese, iron, cobalt, nickel and copper supported on the support, and A second metal selected from platinum group elements supported on the support A catalyst containing the same, It is used for the hydrocracking of epoxy resin, and the epoxy resin may be cured, the catalyst.

2. The catalyst according to claim 1, wherein the second metal is selected from platinum, palladium, rhodium, iridium or ruthenium.

3. The catalyst according to claim 1, wherein the first metal is nickel.

4. The metal oxide support is aluminum oxide (Al ２ O ３ ), titanium oxide (TiO ２ ), zirconium oxide (ZrO ２ ), cerium oxide (CeO ２ ), the catalyst according to claim 1.

5. The metal oxide support is cerium oxide (CeO ２ ), the catalyst according to claim 4.

6. The supported amount of the first metal is 0.01 to 0.50 mmol / g, the catalyst according to claim 1.

7. The supported amount of the second metal is 0.01 to 0.5 mmol / g, the catalyst according to claim 1.

8. The molar ratio of the second metal / the first metal is 0.01 to 100, the catalyst according to claim 1.

9. A method of using the catalyst according to claims 1 to 8 for the hydrocracking of epoxy resin.

10. A metal oxide support, At least one first metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper, supported on the carrier, and A second metal selected from platinum group elements, supported on the carrier Using a catalyst containing A method for preparing phenols by hydrocracking an epoxy resin which may be cured.

11. The method according to claim 10, wherein the phenols are any one or more of the following Compounds 1 to 3.

12. The method according to claim 11, wherein Compound 1 and / or any one or more of Compounds 2 and 3 can be obtained as the phenols.

13. To a composite material containing an epoxy resin which may be cured and fibers, A metal oxide carrier, At least one first metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper, supported on the carrier, and A second metal selected from platinum group elements, supported on the carrier A method for recovering fibers from a composite material by hydrocracking the epoxy resin using a catalyst containing

14. The method according to claim 13, wherein the fibers are one or more fibers selected from the group consisting of glass fiber, carbon fiber, ceramic fiber, aramid fiber, boron fiber, silica fiber, metal fiber, mineral fiber, rock fiber, and slag fiber.

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