Metal-supported catalyst, method for producing alcohol, and hydrogenation method

Abstract

A metal-supported catalyst for hydrogenation of carboxylic acids and / or carboxylic acid esters, in which ruthenium, tin, and platinum are supported on a support, said metal-supported catalyst further supporting iron, and chromium and / or molybdenum. It is possible to provide a catalyst having a lower yield of by-products while maintaining high catalytic activity, a method for producing an alcohol from a carboxylic acid and / or a carboxylic acid ester using the catalyst, and a method for hydrogenating a carboxylic acid and / or a carboxylic acid ester.

Description

Technical Field

[0001] The present invention relates to a metal-supported catalyst, and more particularly to a metal-supported catalyst capable of hydrogenating a carboxylic acid and / or a carboxylic acid ester with high selectivity, a method for producing an alcohol using the metal-supported catalyst, and a hydrogenation method. Background Art

[0002] As a catalyst for reducing carboxylic acid and / or carboxylic acid ester to the corresponding alcohol, a catalyst obtained by loading ruthenium, tin and platinum on a carrier and subjecting it to reduction treatment with hydrogen etc. has been proposed (e.g., Patent Documents 1 and 2). The catalyst shows high reactivity and reaction selectivity in the hydrogenation of carboxylic acid and / or carboxylic acid ester, and is a good catalyst.

[0003] In addition, a catalyst in which iron is also supported in a reduction catalyst is disclosed in Patent Document 3. More specifically, a supported catalyst in which nitrates of iron, cobalt and nickel are added to a reduction catalyst supporting ruthenium, platinum and tin as main component metals is disclosed, and the production of 1,4-cyclohexanedimethanol is disclosed.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2001-9277

[0007] Patent Document 2: International Publication No. 2015 / 178459

[0008] Patent Document 3: Chinese Patent No. 104722321 Summary of the invention

[0009] Problems to be solved by the invention

[0010] When the hydrogenation reaction of carboxylic acid and / or carboxylic acid ester is carried out using the catalysts described in the conventionally known Patent Documents 1 and 2, although the hydrogenation activity is high, by-products accompanied by the cleavage of CC bonds and CO bonds are generated, the yield of the target product is reduced, and precise operations for removing the by-products are sometimes required.

[0011] Although the catalyst disclosed in Patent Document 3 suppresses the generation of by-products compared to the catalysts described in Patent Documents 1 and 2, the degree of suppression is still insufficient, and further improvement is desired.

[0012] In view of the above situation, the technical problem of the present invention is to provide a catalyst having a lower by-product yield while maintaining high catalytic activity.

[0013] Solutions for solving problems

[0014] The present inventors have found that a metal-supported catalyst in which ruthenium, tin and platinum are supported on a carrier and iron, chromium and / or molybdenum are also supported can significantly reduce the yield of by-products while maintaining high catalytic activity.

[0015] The details are not yet clear, but it is speculated that iron, chromium and molybdenum exhibit the effect of selectively inhibiting the active sites for breaking CC bonds and CO bonds without inhibiting the active sites for reducing carbonyl groups on the catalyst. In particular, it was found that the above effect can be significantly exerted by the combination of iron and chromium, the combination of iron and molybdenum, and the combination of the three components of iron, chromium and molybdenum.

[0016] The gist of the present invention is as follows.

[0017] [1] A metal-supported catalyst, which is a metal-supported catalyst for hydrogenation of carboxylic acid and / or carboxylic acid ester, wherein ruthenium, tin and platinum are supported on a carrier, and the metal-supported catalyst is further supported with iron, chromium and / or molybdenum.

[0018] [2] The metal-supported catalyst according to [1] above, wherein the amount of iron supported is 0.01% by mass or more and 4% by mass or less, and the total amount of chromium and / or molybdenum supported is 0.01% by mass or more and 2% by mass or less, relative to the total mass of the metal-supported catalyst.

[0019] [3] The metal-supported catalyst according to [1] or [2] above, wherein the carrier is a carbonaceous carrier.

[0020] [4] The metal-supported catalyst according to any one of [1] to [3] above, wherein the total amount of ruthenium, tin, platinum, iron, molybdenum and chromium supported is 5% by mass or more relative to the total mass of the metal-supported catalyst.

[0021] [5] The metal-supported catalyst according to any one of [1] to [4] above, wherein the metal-supported catalyst is prepared by hydrogen reduction.

[0022] [6] A method for producing an alcohol, comprising contacting the metal supported catalyst according to any one of [1] to [5] with a carboxylic acid and / or a carboxylic acid ester and reducing the carboxylic acid and / or the carboxylic acid ester to obtain an alcohol corresponding to each of the carboxylic acid and / or the carboxylic acid ester.

[0023] [7] A method for hydrogenating a carboxylic acid and / or a carboxylic acid ester, comprising contacting the metal-supported catalyst according to any one of [1] to [5] with a carboxylic acid and / or a carboxylic acid ester.

[0024] [8] The method for producing an alcohol according to [6] above, wherein the carboxylic acid is 1,4-cyclohexanedicarboxylic acid, and the carboxylic acid ester is 1,4-cyclohexanedicarboxylic acid ester.

[0025] Effects of the Invention

[0026] According to the present invention, there can be provided a catalyst having a lower by-product yield while maintaining high catalytic activity, a method for producing alcohol from carboxylic acid and / or carboxylic acid ester using the catalyst, and a method for hydrogenating carboxylic acid and / or carboxylic acid ester. DETAILED DESCRIPTION

[0027] Hereinafter, an embodiment of the present invention will be described in detail, but the description of the constituent elements described below is an example (representative example) of the implementation of the present invention, and the present invention is not limited to these contents, and can be implemented in various modifications within the scope of the gist.

[0028] It should be noted that, in the present application, metals (ruthenium, tin, platinum, other metals such as iron used as needed) that are sometimes loaded on a carrier are collectively referred to as "metal components". In addition, substances that load the above-mentioned metal components on a carrier, substances obtained by reducing the same, and substances obtained by further oxidative stabilization are collectively referred to as "metal-loaded catalysts". In addition, catalysts that are also loaded with metal components in the "metal-loaded catalyst" that has been subjected to oxidative stabilization are also referred to as "metal-loaded catalysts". It should be noted that catalysts in the stage before the reduction treatment in metal-loaded catalysts are sometimes referred to as "metal-loaded substances".

[0029] [Metal Supported Catalysts]

[0030] The metal-supported catalyst of the present invention (hereinafter, sometimes referred to as "the present catalyst") is obtained by subjecting a metal-supported material in which the above-mentioned metal component is supported on a carrier to reduction treatment using a reducing gas. In addition, the metal-supported catalyst subjected to reduction treatment and subjected to oxidation treatment is also included in the metal-supported catalyst of the present invention. In addition, the metal-supported catalyst is also included in the metal-supported catalyst after these treatments and further adding a metal component.

[0031] The metal-supported catalyst of the present invention is a catalyst containing ruthenium, tin and platinum as essential elements (hereinafter, sometimes referred to as a "reduction catalyst"), and the reduction catalyst is also supported by iron, chromium and / or molybdenum. Specifically, there are the following schemes: a combination of iron and chromium; a combination of iron and molybdenum; a combination of three components of iron, chromium and molybdenum. By making a metal-supported catalyst with such a structure, the yield of by-products accompanied by the breaking of CC bonds and CO bonds can be suppressed to a lower level while maintaining hydrogenation activity.

[0032] For example, when 1,4-cyclohexanedicarboxylic acid as a carboxylic acid is hydrogenated, cyclohexanemethanol accompanied by CC cleavage and 4-methylcyclohexanemethanol accompanied by CO cleavage are generated as by-products along with 1,4-cyclohexanedimethanol as the target product, and the yield of the target product is reduced. In contrast, by using the catalyst of the present invention, the generation of by-products can be effectively suppressed.

[0033] In addition, 1,4-cyclohexanedimethanol, which is a diol compound, is often used as a raw material for resins such as polyesters and polyurethanes. In this case, monohydric alcohols such as cyclohexanemethanol and 4-methylcyclohexanemethanol act as polymerization inhibitors, so they must be avoided during resin synthesis and need to be removed. On the other hand, when the amount of by-products generated in the hydrogenation reaction is reduced, there is an advantage that the purification operation of removing the monohydric alcohol can be simplified or skipped.

[0034] <Carrier>

[0035] As the carrier used in the present invention, there is no particular limitation as long as it has a large surface area and can load metal components. For example, carbonaceous carriers such as activated carbon and carbon black; inorganic porous carriers such as alumina, silica, diatomaceous earth, zirconium dioxide, titanium dioxide, and hafnium dioxide; silicon carbide, gallium nitride, etc. are used. Among them, carbonaceous carriers such as activated carbon, graphite, and black lead, titanium dioxide, and zirconium dioxide are preferred. From the perspective of excellent stability and easy industrial availability, carbonaceous carriers are more preferred. From the perspective of high surface area, excellent metal dispersibility, and easy to improve reaction activity, activated carbon is further preferred. It should be noted that the carrier can be used alone or in combination of two or more.

[0036] The carrier can be used directly or pretreated into a form suitable for loading. For example, if a carbonaceous carrier is used, the carbonaceous carrier can be used after being heated with nitric acid as described in Japanese Patent Publication No. 10-71332. By the above method, the dispersion of the metal component on the carrier can be improved, and the activity of the obtained catalyst can be improved.

[0037] The shape and size of the carrier used in the present invention are not particularly limited. When the shape is converted into a spherical shape, the average primary particle size is usually 50 μm or more and 5 mm or less, preferably 4 mm or less. It should be noted that the particle size is measured by the sieving test method described in JIS standard JIS Z8815.

[0038] The appropriate particle size of the carrier is different according to the reaction using this catalyst, so it is preferably adjusted according to the reaction. Specifically, in the case where the reaction using this catalyst is a completely mixed reaction, the particle size of the carrier is usually more than 50 μm, preferably more than 100 μm, usually less than 3 mm, preferably less than 2 mm. The smaller the particle size of the carrier, the higher the activity per unit mass of the obtained catalyst, which is preferred in this respect, but when the particle size of the carrier is too small, it is sometimes difficult to separate the reaction solution from the catalyst. That is, when the particle size of the carrier is more than the above-mentioned lower limit, it is preferred in terms of reaction activity, and when the particle size of the carrier is less than the above-mentioned upper limit, it is preferred to be easily separated from the reaction solution.

[0039] In addition, when the shape of the carrier is not spherical, the volume of the carrier is calculated and converted into the diameter of spherical particles of the same volume.

[0040] In addition, when the reaction using the present catalyst is a fixed bed reaction, the particle size of the carrier is usually 0.5 mm or more and 5 mm or less, preferably 4 mm or less, and more preferably 3 mm or less. When the particle size of the carrier is above the above lower limit, it will not be difficult to operate due to differential pressure, and when the particle size of the carrier is below the above upper limit, sufficient reaction activity can be obtained.

[0041] <Metal component>

[0042] The metal-supported catalyst of the present invention is a catalyst in which ruthenium, tin, and platinum are supported on a carrier as essential elements, and the catalyst is also supported with iron, chromium, and / or molybdenum (hereinafter, sometimes referred to as "other metals such as iron"). By adding additional supported iron, chromium, and / or molybdenum, the generation of by-products can be further suppressed. With regard to the generation suppression effect of by-products, a higher effect can be obtained by supporting iron, chromium, and / or molybdenum.

[0043] In addition, in addition to ruthenium, tin, platinum, iron, chromium, and molybdenum, other metals may be further included as needed as long as they do not adversely affect reactions such as reduction reactions using the present catalyst. It is preferred that it include at least one metal selected from the group consisting of rhodium, tungsten, rhenium, barium, boron, and more preferably includes rhenium.

[0044] In addition, the raw materials of each metal component are described below.

[0045] (Metal component loading)

[0046] The load of the metal component of this catalyst is not particularly limited, and is determined by each metal. The load of ruthenium is usually more than 1 mass % in terms of the mass ratio relative to the total mass of the metal-supported catalyst, preferably more than 3 mass %, usually less than 10 mass %, preferably less than 8 mass %. Similarly, the load of tin is usually more than 1 mass %, preferably more than 2 mass %, usually less than 15 mass %, preferably less than 10 mass % in terms of the mass ratio relative to the total mass of the metal-supported catalyst. In addition, similarly, the load of platinum is usually more than 0.5 mass %, usually less than 7 mass %, preferably less than 5 mass % in terms of the mass ratio relative to the total mass of the metal-supported catalyst. By being set to these ranges, the ability of hydrogenation catalyst is improved, therefore preferably. Moreover, the load of iron, and chromium and / or molybdenum is preferably respectively more than 0.01 mass % and less than 4 mass %, more preferably less than 2 mass %. By being set to this range, the generation of by-products can be significantly reduced. That is, the loading amount of iron is preferably 0.01 mass % or more and 4 mass % or less, and more preferably 0.01 mass % or more and 2 mass % or less. With respect to the loading amount of chromium and / or molybdenum, in the case of loading either side, the range of the appropriate loading amount of each metal is 0.01 mass % or more and 4 mass % or less, and more preferably 0.01 mass % or more and 2 mass % or less. In the case of loading both chromium and molybdenum, the total loading amount of the two sides is preferably within the above range. In addition, in order to fully obtain the effect of suppressing by-products brought about by the combined use of iron and chromium, their composition ratio is not particularly limited as long as it is within the above range, for example, 100: 1 to 1: 100 is used, more preferably 10: 1 to 1: 10, and more preferably 10: 1 to 1: 5. In addition, the same range is also preferred in the case of combining iron and molybdenum. On the other hand, in terms of cost, chromium and molybdenum are more expensive than iron, so in this sense, it is preferred to be less than iron.

[0047] The total amount of ruthenium, tin, platinum and other metals such as iron loaded relative to the total mass of the metal-loaded catalyst is not particularly limited, and is usually 5% by mass or more, preferably 8% by mass or more, more preferably 10% by mass or more, and is usually 40% by mass or less, preferably 30% by mass or less, and more preferably 20% by mass or less.

[0048] It should be noted that the above-mentioned metal loading is a value obtained by converting all the loaded metals into metal atoms. In addition, the size of the metal-supported catalyst after reduction of the present invention is not particularly limited and is basically the same as the size of the above-mentioned carrier.

[0049] It should be noted that the loading amount of the loaded metal (hereinafter, sometimes described as "metal") can be measured, for example, by the following method. The catalyst can be pulverized and stirred to form a uniform state, disc-formed as needed, and analyzed by fluorescent X-ray analysis while maintaining a solid state. Alternatively, a uniform solution can be prepared after alkali melting decomposition or pressurized decomposition using microwaves, and analyzed by ICP emission spectrometry (high-frequency inductively coupled plasma emission spectrometry).

[0050] Among them, ICP emission spectrometry (high frequency inductively coupled plasma emission spectrometry) is preferred because a more accurate measurement result can be obtained by making a uniform solution.

[0051] <Method for producing catalyst>

[0052] In the present invention, the method for producing a catalyst includes: a step of loading the above-mentioned metal component on a carrier (hereinafter referred to as a metal loading step), and then a step of reducing the obtained metal loading product using a reducing gas. Each step will be described below in turn.

[0053] <<Metal Loading Process>>

[0054] The metal loading step is a step of loading the metal component on the carrier to obtain a metal loaded product. The loading method of the metal component is not particularly limited, and a known method can be used. When loading, solutions or dispersions of various metal compounds as raw materials of the metal component can be used.

[0055] (Metal loading method)

[0056] The method of loading the metal component on the carrier is not particularly limited, and various impregnation methods can generally be applied. For example, there are: an adsorption method that utilizes the adsorption force of metal ions on the carrier to adsorb metal ions below the saturated adsorption amount; an equilibrium adsorption method that immerses the carrier in a solution of metal ions above the saturated adsorption amount and removes the excess solution; a pore-filling method that adds a solution of metal ions in an amount equal to the pore volume of the carrier and allows the solution to be completely adsorbed on the carrier; an incipient wetness method that adds a solution of metal ions until it is commensurate with the water absorption of the carrier, and ends when the surface of the carrier is uniformly wetted and there is no excess solution; an evaporation-to-drying method that allows the solution of metal ions to be impregnated into the carrier and the solvent is evaporated while stirring; a spray method that allows the carrier to be in a dry state and sprays the solution, etc.

[0057] Among the above methods, pore filling method, incipient wetness impregnation method, evaporation to dryness method, and spraying method are preferred, and pore filling method, incipient wetness impregnation method, and evaporation to dryness method are more preferred. By the above methods, other metal components such as ruthenium, tin, platinum, and iron can be loaded in a relatively uniformly dispersed state.

[0058] The load can be loaded together after preparing all the metal solutions of the load, or it can be loaded separately by each metal. In addition, in the case of separate loads, it can be loaded separately by each type, or it can be loaded separately with a variety of metal solutions. From the aspect of shortening the loading process, it is preferred to load all the metal solutions together or load separately with a variety of metals. The time point of the separate load is not particularly limited, and it can be just to load a variety of metals several times, or it can be loaded separately after loading to the middle of the process until hydrogen reduction, or it can be loaded separately on the metal-loaded catalyst after hydrogen reduction.

[0059] (Metal Compounds)

[0060] As the metal compound for loading, there is no particular limitation and it can be appropriately selected according to the loading method. For example, halides such as chloride, bromide, iodide, inorganic acid salts such as nitrates and sulfates, organic acid salts such as acetates, metal hydroxides, metal oxides, organometallic compounds, metal complexes, etc. can be used. Among them, halides, inorganic acid salts, organic acid salts, etc. are preferred, halides and inorganic acid salts are more preferred, and halides are further preferably used, and chlorides such as hydrochlorides are particularly preferred among halides. In addition, it is preferred that at least one of the above-mentioned metal compounds is chloride, and it is more preferred that all of them are chlorides. It is believed that by using chlorides, the metals are complexed in a solution state, and the dispersion state of each metal on the loaded carrier becomes uniform, thereby stably loading. In addition, the growth of alloy particles based on other metal components such as ruthenium, tin, platinum and iron in the obtained catalyst is suppressed, the activity and selectivity are improved, and the stability of the catalyst in the reaction is improved.

[0061] More specifically, in the case of ruthenium, examples include ruthenium chloride, ruthenium nitrosyl nitrate, tris(acetylacetonate)ruthenium, etc. These ruthenium salts may be used alone or in combination of two or more.

[0062] In the case of tin, specific examples include tin compounds such as tin chloride (II), tin chloride (IV), tin acetate (II), tin acetate (IV), dibutyltin dilaurate, dibutyltin oxide, and dibutyltin dimethoxy. The tin compounds may be used alone or in combination of two or more.

[0063] In the case of platinum, a platinum precursor compound is used, and examples of the platinum precursor compound include hexachloroplatinic acid (IV) (hexahydrate, etc.), potassium tetrachloroplatinate (II), potassium hexachloroplatinate (IV), potassium tetracyanoplatinate (II), sodium hexachloroplatinate (IV) (hexahydrate), hexahydroplatinic acid (IV), potassium tetracyanoplatinate (II) (hydrate), tetrabutylammonium hexachloroplatinate (IV), etc. The platinum precursor compound may be used alone or in combination of two or more.

[0064] As other metal compounds such as iron, specifically, the iron salts, chromium compounds, and molybdenum compounds exemplified below can be used.

[0065] As the iron salt, it is preferable to use an iron salt selected from the group consisting of iron chloride, iron nitrate, iron sulfate, and iron acetylacetonate.

[0066] As the chromium compound, inorganic acid salts such as chromium nitrate, chromium sulfate, and chromium chloride; organic acid salts such as chromium acetate, chromium oxalate, and chromium acetylacetonate; and various chromium compounds known for use in producing chromium oxide catalysts can be used.

[0067] As the molybdenum compound, a molybdenum compound containing an oxidized molybdenum element is preferred, and examples thereof include molybdenum trioxide, molybdic acid, molybdates, heteropoly acids, and the like. Among them, molybdenum trioxide and molybdates are more preferred. As molybdates, for example, there are ammonium paramolybdate, ammonium dimolybdate, ammonium tetramolybdate, and the like. The molybdenum raw material may be used alone or in combination of two or more.

[0068] (Solvent)

[0069] When the above-mentioned metal compound is loaded on a carrier, various solvents can be used to dissolve or disperse the metal compound for various loading methods. As for the type of solvent used at this time, as long as the metal compound can be dissolved or dispersed, it will not cause adverse effects on the subsequent calcination and hydrogen reduction of the metal load, and the hydrogenation reaction using the catalyst of the present application. For example, ketone solvents such as acetone; alcohol solvents such as methanol and ethanol; ether solvents such as tetrahydrofuran and ethylene glycol dimethyl ether; water, etc. These solvents can be used alone or in the form of a mixed solvent. In the present invention, as described above, as the above-mentioned metal compound, it is preferred to use a halide, and it is more preferred to use a chloride. In order to make the solubility of these halides high, it is preferred to use water.

[0070] In addition, when the metal compound is dissolved or dispersed, in addition to the solvent, various additives may be added. For example, by adding carboxylic acid and / or carbonyl compound solution as described in Japanese Patent Laid-Open No. 10-15388, the dispersibility of each metal component on the carrier can be improved when it is supported on the carrier.

[0071] <Metal load>

[0072] The metal supported material in which the above-mentioned metal component is supported on a carrier can be dried as needed and used, preferably dried. When the metal supported material is subjected to a subsequent reduction treatment in an undried state, the reaction activity is sometimes reduced, and in particular, in the case of a dehalogenation treatment described later, it is preferred to dry it from the aspect of being able to suppress the dissolution of the metal salt in the presence of a base commonly used in the dehalogenation treatment.

[0073] The drying method is not particularly limited as long as the solvent used for the support can be removed. It is usually carried out in the presence or flow of an inert gas.

[0074] The drying pressure is not particularly limited, and the drying is usually carried out under normal pressure or reduced pressure.

[0075] The drying temperature is not particularly limited, but is usually 300°C or lower, preferably 250°C or lower, more preferably 200°C or lower, and usually 80°C or higher.

[0076] <Dehalogenation and cleaning>

[0077] The above-mentioned metal load can be subjected to dehalogenation treatment as needed before the reduction process described later. In the above-mentioned metal loading process, especially when a halide such as chloride is used as a raw material for the metal component, a halogen compound is sometimes generated in the reduction device in the reduction process described later. Although it will not be a problem in terms of the processing volume on a laboratory scale, when a large amount of reduction treatment is carried out industrially, a large amount of halogen compounds are generated in the reduction device, and sometimes waste gas needs to be treated, and sometimes corrosion of the device occurs. Therefore, it is preferred to carry out dehalogenation treatment before implementing the reduction process.

[0078] The method for dehalogenation treatment is not particularly limited, and generally the metal support can be brought into contact with an alkaline compound in a gas phase or a liquid phase, and the halide in the metal support can be reacted and then removed by gas phase treatment or washing. Among them, from the perspective of ease of operation and good efficiency of removing the halide from the metal support, it is preferred to contact with an alkaline compound in a liquid phase for treatment and then remove by washing. Specifically, it is more preferred to wash with water after contact with an alkaline aqueous solution.

[0079] The dehalogenation treatment temperature is not particularly limited, and is usually carried out at 10° C. or more, preferably at 20° C. or more, usually at 150° C. or less, preferably at 100° C. or less, and more preferably at 80° C. or less. When the dehalogenation treatment temperature is above the above lower limit, the dehalogenation treatment can be carried out efficiently. In addition, when the dehalogenation treatment temperature is below the above upper limit, volatilization, thermal decomposition, etc. of the solvent or the alkali compound used in the treatment will not occur.

[0080] In the case of using an alkaline aqueous solution in the dehalogenation treatment, the pH of the alkaline aqueous solution is not particularly limited, and the pH is usually more than 7.5, preferably more than 8.0, usually less than 13.0, preferably less than 12.5. When the pH of the alkaline aqueous solution is below the above-mentioned upper limit, there is no worry about the deterioration of the loaded metal caused by the high pH, ​​and it is not easy to cause the dissolution of the loaded metal in the cleaning process described later. In addition, when the pH of the alkaline aqueous solution is above the above-mentioned lower limit, sufficient dehalogenation can be carried out.

[0081] As the type of the alkaline compound, for example, carbonates, bicarbonates, ammonia or ammonium carbonate, bicarbonate of ammonium, etc. of alkali metals can be used. They can be used alone or in combination of two or more. Among them, weakly alkaline alkaline compounds are preferred. Compared with the use of strongly alkaline alkaline compounds, the use of weakly alkaline alkaline compounds such as ammonia and ammonium salts tends to obtain catalysts with high activity.

[0082] As the amount of the alkaline compound, 0.1 to 50 equivalents are usually used relative to the halogen ions contained in the carrier, preferably 1 to 20 equivalents, and more preferably 1 to 10 equivalents. The alkaline compound is usually used in the form of an aqueous solution, but water-soluble solvents such as methanol, ethanol, acetone, and ethylene glycol dimethyl ether, and mixed solvents thereof with water can also be used. The alkaline aqueous solution is preferably used in an amount that completely fills the pores of the carrier loaded with the metal component of the metal support, that is, an amount greater than the pore volume of the carrier is used. The amount of the alkaline aqueous solution used also depends on the concentration of the alkaline aqueous solution, so it is not particularly limited, and is usually more than 0.8 times and less than 20 times the pore volume of the carrier of the metal support used, preferably more than 1 time and less than 10 times, and more preferably more than 1 time and less than 5 times.

[0083] The metal support treated with the alkali compound is preferably washed to remove excess alkali compounds and generated halides. For washing, any solution that dissolves the excess alkali compound and generated halides can be used, and water is preferred. In this case, the washing temperature is not particularly limited, and washing is usually carried out at a temperature of 10° C. or more and 100° C. or less, but from the perspective of good washing efficiency in warm water, it is preferably 40° C. or more, and more preferably 50° C. or more.

[0084] After the alkali treatment or the washing, further drying may be performed as necessary. The same drying conditions as those for drying the metal-supported material may be used.

[0085] <Reduction Treatment and Reducing Gas>

[0086] The metal supported material is preferably subjected to reduction treatment using a reducing gas to prepare a metal supported catalyst. The reducing gas in the present invention is not particularly limited as long as it is a reducing substance, such as hydrogen, methanol, hydrazine, etc., preferably hydrogen. In other words, the metal supported catalyst of the present invention is preferably prepared by hydrogen reduction.

[0087] It should be noted that in the reduction treatment of the present invention, regardless of the type of reducing gas, a reduction reaction occurs to form a metal-supported catalyst. The amount of reducing gas required for the reduction treatment is expressed as "hydrogen absorption amount".

[0088] In the present invention, the reduction treatment of the metal-supported material may be performed in one step or in multiple steps without particular limitation.

[0089] (Reduction treatment temperature)

[0090] When producing the metal-supported catalyst of the present invention, it is preferred to carry out the reduction treatment while controlling the treatment temperature region.

[0091] The reduction treatment temperature is not particularly limited, and may be a constant temperature or a variable temperature. It is usually 80°C or higher, preferably 100°C or higher, more preferably 150°C or higher, and usually 650°C or lower, preferably 600°C or lower, more preferably 580°C or lower. When the reduction treatment temperature is below the upper limit temperature, there is no sintering of the metal component and no adverse effect on the carrier. On the other hand, when the reduction treatment temperature is above the lower limit value, the reduction reaction is fully carried out.

[0092] Specifically, the reduction treatment can be carried out under a state of keeping a certain time at a specific temperature in a preferred temperature range, or it can be carried out while heating up a certain time in a preferred temperature range. From the viewpoint of efficiency of the reaction time, due to the reduction treatment, the metal load is accompanied by heat, and the temperature of the reaction system rises, so it is preferred to heat up for a certain time while carrying out the reduction treatment. On the other hand, in the case of intense heat generation, it is preferred to maintain the method at a certain temperature in a controlled manner that can accurately react.

[0093] (Reducing gas concentration)

[0094] The concentration of the reducing gas during the reduction treatment of this catalyst is not particularly limited, and can be 100% by volume of the reducing gas, or it can be diluted with an inert gas. The inert gas mentioned here refers to a gas that does not react with a metal support or a reducing gas, and nitrogen, water vapor, etc. can be listed, and nitrogen is usually used. Relative to all gas components, the concentration of the reducing gas during dilution with an inert gas is usually more than 5% by volume, preferably more than 15% by volume, more preferably more than 30% by volume, and further preferably more than 50% by volume. In addition, it is also possible to use a low concentration of reducing gas in the initial stage of reduction, and then slowly increase the concentration of the reducing gas to carry out the reduction treatment.

[0095] (flow)

[0096] In order to determine the flow rate of the reducing gas, it is preferred to know in advance the amount of hydrogen absorbed during catalyst reduction. The method for determining the amount of hydrogen absorbed is not particularly limited, and it is generally preferred to reduce the amount of hydrogen supplied per unit time and the heating time per unit time by a method, i.e., a temperature programmed reduction method (hereinafter referred to as a TPR method). By using this method, the amount of hydrogen absorbed and the absorption temperature of the catalyst can be precisely determined.

[0097] In the TPR method, a catalyst to be measured is placed in a container, a certain flow of hydrogen is passed through the container while the temperature is raised, and the amount of hydrogen at the inlet and outlet of the container is continuously measured. By this method, the amount of hydrogen absorbed during the reduction of the metal-supported catalyst can be determined. Specifically, it can be measured by the method described in the examples.

[0098] During the reduction treatment of the catalyst, the reducing gas can be used in a sealed reactor or circulated in the reactor, preferably circulated in the reactor. Due to the reduction treatment, water, ammonium chloride, etc. are produced as byproducts in the reactor. These byproducts sometimes have an adverse effect on the metal load before the reduction treatment, the metal load after the reduction treatment, and the obtained catalyst. The circulation of the reducing gas in the reactor can prevent this situation. That is, by circulating the reducing gas, the byproducts can be discharged outside the reaction system.

[0099] The amount of reducing gas required for reduction treatment is not particularly limited as long as the purpose of the present invention is achieved, and can be appropriately set according to the device for reduction, the size of the reactor during reduction, and the flow conditions. Usually, relative to the hydrogen absorption amount obtained by the above-mentioned TPR method, under the condition of high contact efficiency such as hydrogen circulation in the catalyst layer, the amount of reducing gas required for reduction treatment is set to a flow rate of more than 1.5 times, preferably more than 2 times, more preferably more than 3 times, and particularly preferably more than 5 times the amount of hydrogen required for each reduction treatment. When the amount of reducing gas required for reduction treatment is above the above lower limit, especially when the contact efficiency with hydrogen is sufficient, the reduction is fully carried out. The upper limit is not particularly limited, and from the perspective of no waste gas treatment problems, no scattering of metal loads or manufactured catalysts caused by reducing gases, and avoiding the waste of excess reducing gases, it is usually set to less than 500 times, preferably less than 200 times.

[0100] (Restore processing time)

[0101] The time required for the reduction treatment varies depending on the amount of the metal support to be treated, the device used, etc., and is usually 7 minutes or more, preferably 15 minutes or more, more preferably 30 minutes or more, further preferably 1 hour or more, and most preferably 2 hours or more, and is usually 40 hours or less, preferably 30 hours or less.

[0102] The degree of reduction of the above-mentioned metal load can be judged by the halogen concentration in the metal-supported catalyst of oxidation stabilization after the reduction treatment described later. The halogen concentration in the above-mentioned metal-supported catalyst is not particularly limited, and is usually 0.8% by mass or less, more preferably 0.7% by mass or less, and further preferably 0.5% by mass or less. When the halogen concentration is low, when the reduction reaction of the present catalyst is used, the halogen can be suppressed from dissolving into the reaction solution, so it is preferred. The lower limit of the halogen concentration is not particularly limited, and is usually 0.005% by mass or more, preferably 0.01% by mass or more. When the halogen concentration is within the above range, the reduction treatment of the metal load is fully carried out, and the dissolution of the halogen into the reaction solution can be suppressed to be low, and the activity of the reduction reaction using the present catalyst is improved, and the reaction selectivity is also improved, and the stability of the catalyst is also improved.

[0103] <Preferred Manufacturing Method>

[0104] The method for producing the catalyst of the present invention is as described above, and is subjected to a metal loading step, a dehalogenation step, a cleaning step, and a reduction step. As a preferred method of producing the catalyst, there are: a method of passing a reducing gas through a catalyst on a fixed bed in the reduction step; a method of circulating a reducing gas through a catalyst stationary on a tray or a belt; a method of circulating a reducing gas through a flowing catalyst. Among them, it is preferred to carry out the reduction treatment while flowing the metal load in the reduction treatment. By carrying out the reduction treatment while flowing, the surface area of ​​the metal load in contact with the reducing gas during the reduction treatment increases, thereby improving the efficiency of the reduction treatment.

[0105] There are no particular limitations on the specific method for performing the flow, as long as it is accompanied by an action that increases the contact surface area between the metal support etc. to be reduced and the reducing gas. Examples include: a method of rotating the reactor containing the metal support etc. to be reduced; a method of introducing a device that stirs the metal support etc. in the reactor or moves the metal support etc. in the reactor up and down.

[0106] As a specific flowing method, there is a method of treating using various kilns (heating furnaces).

[0107] As a specific preferred production method, for example, there is mentioned a method using a continuous kiln or a batch kiln.

[0108] (Continuous Kiln)

[0109] The continuous kiln refers to a kiln that can continuously supply a metal support to carry out reduction and continuously discharge the reduced catalyst. Specifically, there are continuous rotary kilns, roller kilns, belt kilns, tunnel kilns, etc. Among them, in the production method of the present invention, a continuous rotary kiln is preferred from the perspective of high fluidity of the metal support and high contact efficiency with the reducing gas.

[0110] The operating conditions of the continuous kiln are not particularly limited as long as the above-mentioned reduction treatment conditions are met, and can be appropriately set according to the device used. Generally, in a continuous kiln, the flow rate and temperature of the reducing gas can be managed to meet the above-mentioned reduction treatment conditions.

[0111] The continuous kiln can continuously supply the metal support and the reducing gas, so the supply method of the metal support and the flow rate of the reducing gas into the continuous kiln can be controlled.

[0112] The flow rate of the reducing gas in the continuous kiln is not particularly limited. The amount of hydrogen required for reduction calculated by TPR measurement of the metal support is defined as the "hydrogen absorption amount A (m 3 / kg)”, when the amount of metal support fed into the continuous kiln is B (kg / h), the hydrogen flow rate is usually (1.5×A×B)m 3 / h or more, preferably (2×A×B)m 3 / h or more, more preferably (5×A×B)m 3 / h or more. When the hydrogen flow rate is above the lower limit, sufficient hydrogen can be ensured for the catalyst to absorb, and the performance of the obtained catalyst can be maintained at a high level. There is no particular upper limit. In order to reduce the amount of wasted hydrogen, the upper limit is (1000×A×B)m 3 / h or less, preferably (500×A×B)m 3 / h or less, more preferably (300×A×B)m 3 / h or less.

[0113] The flow direction of the metal support subjected to the reduction treatment in the continuous kiln and the flow direction of the reducing gas such as hydrogen can be appropriately adjusted according to the conditions of the reduction treatment, and the reduction treatment can be carried out in a parallel flow or countercurrent flow of the reducing gas and the metal support. Among them, from the perspective of the catalyst reaching the outlet of the continuous kiln being able to contact with high-purity hydrogen, it is preferred that the flow direction of hydrogen and the flow direction of the metal support be countercurrent (in opposite directions to each other).

[0114] The rotation speed of the continuous rotary kiln is not particularly limited. A high rotation speed improves the contact efficiency between the metal support and hydrogen, but causes catalyst wear, so it is usually 0.5 rpm or more and 10 rpm or less, preferably 5 rpm or less.

[0115] (Batch Kiln)

[0116] An intermittent kiln is a kiln in which a predetermined amount of metal load is loaded into the kiln in advance, and the temperature is gradually raised to the target reduction temperature under the circulation of reducing gas, and reduction is carried out at the predetermined temperature. Specifically, there are: a fixed bed heating furnace in which the metal load is filled and treated, a plate heating furnace in which the metal load is placed on a tower plate for heating, a shuttle kiln in which a firing trolley enters and exits an electric furnace, and an intermittent rotary kiln.

[0117] From the perspective of contact efficiency between the metal support and the reducing gas, a fixed-bed heating furnace or a batch rotary kiln filled with the metal support for treatment is preferred. From the perspective of uniform reduction, a batch rotary kiln equipped with a device for fluidizing the catalyst is preferred.

[0118] Due to limitations in the equipment, continuous kilns are usually operated at a constant flow rate when introducing reducing gas. In contrast, intermittent kilns have reaction tanks for each batch, so the heating method, flow rate and concentration of the reducing gas can be changed for each batch.

[0119] (Operation conditions of intermittent kiln)

[0120] The operating conditions of the batch kiln are not particularly limited and can be appropriately set according to the configuration of the apparatus and the like.

[0121] The batch type rotary kiln preferably used in the present invention starts heating after a predetermined amount of metal support is loaded in advance, so the heating time to the final reduction temperature can be controlled in more detail than in a continuous type rotary kiln.

[0122] The time of reduction treatment is not particularly limited, and is usually more than 1 hour, preferably more than 2 hours, usually less than 40 hours, preferably less than 30 hours, more preferably less than 10 hours. When the time of reduction treatment is too short than the above-mentioned lower limit, in the case of rapid hydrogen absorption, a large amount of metal loads are once reduced, therefore sometimes huge hydrogen absorption occurs while violently heating, the sintering of catalyst is carried out, and it is difficult to carry out stable operation. In addition, when the time of reduction treatment is more than the above-mentioned lower limit, it is possible to ensure the reduction time, and reduction is sufficient, and sufficient reactivity and selectivity as catalyst can be obtained.

[0123] On the other hand, when the time of the reduction treatment is equal to or less than the upper limit, the productivity of the catalyst can be ensured and there is no loss of hydrogen, which is industrially advantageous.

[0124] When a batch-type rotary kiln is used, the concentration, flow rate, etc. of the reducing gas can be appropriately changed for each batch according to the conditions of the reduction treatment.

[0125] The preferred concentration of the reducing gas during the operation of the batch-type rotary kiln is the same as described above.

[0126] The flow rate of reducing gas is not particularly limited, and can be appropriately set according to the situation of reduction reaction, and the amount of hydrogen required until the end of reduction is calculated by TPR analysis of unreduced catalyst, usually using more than 5 times of its required amount of hydrogen, preferably using more than 10 times, more preferably using more than 20 times. In addition, it is usually set to less than 5000 times, preferably set to less than 1000 times. If the flow rate of reducing gas is more than the above-mentioned lower limit, then lack of hydrogen will not occur, if the flow rate of reducing gas is less than the above-mentioned upper limit, then unnecessary reducing gas will not be consumed, which is economically advantageous.

[0127] The rotation speed of the batch type rotary kiln is not particularly limited. A faster rotation speed improves the contact efficiency with hydrogen, but causes catalyst abrasion. Therefore, the kiln is usually operated at 0.5 to 10 rpm, preferably 0.5 to 5 rpm.

[0128] (Oxidative Stabilization of Catalyst)

[0129] In the manufacture of the metal-supported catalyst of the present invention, the oxidation state of the metal-supported catalyst obtained by reducing the above-mentioned metal support is usually controlled. In the case of mass production of catalysts, it is preferred to perform oxidation stabilization of the catalyst. The metal-supported catalyst obtained by reduction is in a state in which the metal component is reduced and highly dispersed. Compared with directly taking it out into the air, by performing oxidation stabilization, the possibility of metal sintering caused by rapid heat generation can be reduced, and the possibility of ignition (if it is a combustible carrier, it is the ignition of itself and the ignition of the surrounding combustibles) can also be reduced, so it is preferred. By stabilizing under controlled conditions, high dispersibility can be maintained, and high activity is shown in subsequent hydrogenation reactions.

[0130] The above-mentioned oxidation stabilization method is not particularly limited, and there are: a method of adding water to the catalyst or a method of putting the catalyst into water; a method of performing oxidation stabilization with a gas of low oxygen concentration diluted with an inert gas under circulation; a method of stabilizing with carbon dioxide, etc. Among them, the method of adding water to the catalyst or a method of putting the catalyst into water, and the method of performing oxidation stabilization with a gas of low oxygen concentration are preferred, and the method of performing oxidation stabilization with a gas of low oxygen concentration (hereinafter referred to as "slow oxidation method") is more preferred, and oxidation stabilization under the circulation of a gas of low oxygen concentration is further particularly preferred.

[0131] The oxygen concentration when performing oxidation stabilization with a gas with a low oxygen concentration is not particularly limited. As the oxygen concentration at the beginning of slow oxidation, it is usually set to 0.2 volume % or more, preferably 0.5 volume % or more, on the other hand, it is set to 10 volume % or less, preferably 8 volume % or less, and more preferably 7 volume % or less. When the oxygen concentration is above the above lower limit, the time for complete oxidation stabilization can be shortened, and stabilization is sufficient. On the other hand, when the oxygen concentration is below the above upper limit, the catalyst will not reach a high temperature, so there is no need to worry about deactivation. It should be noted that in order to prepare a gas with a low oxygen concentration, it is preferred to dilute the air with an inert gas, and nitrogen is preferred as the inert gas.

[0132] The oxygen concentration during the slow oxidation may be maintained at the oxygen concentration at the start of the slow oxidation. However, if the internal temperature of the catalyst is high and the catalyst is not deteriorated, the oxygen concentration may be gradually increased after the start of the slow oxidation.

[0133] When the slow oxidation at low oxygen concentration is stable, the temperature of the catalyst is preferably controlled to be no more than 130°C. When the temperature of the catalyst is below 130°C, rapid oxidation does not occur, so the catalyst does not sinter, and the strength of the carrier does not decrease and is maintained. From the above viewpoints, it is preferred to control the oxygen concentration and flow rate so that the temperature of the catalyst does not exceed 120°C, and further preferably does not exceed 110°C.

[0134] Methods for oxidative stabilization using a gas with a low oxygen concentration include: a method of passing a gas with a low oxygen concentration through a catalyst on a fixed bed; a method of circulating a gas with a low oxygen concentration through a catalyst placed stationary on a tray or a belt; and a method of circulating a gas with a low oxygen concentration through a flowing catalyst.

[0135] The better the dispersion of the supported metal on the metal-supported catalyst, the more rapidly the oxidation stabilization proceeds and the larger the amount of oxygen reacts. Therefore, among the above methods, the method of passing a gas with a low oxygen concentration through the catalyst on a fixed bed and the method of circulating a gas with a low oxygen concentration in a flowing catalyst are preferred, and the method of circulating a gas with a low oxygen concentration in a flowing catalyst is particularly preferred.

[0136] (Method for storing catalyst)

[0137] When the metal supported catalyst of the present invention is stored, it is preferably stored in an atmosphere with an oxygen concentration of 15 volume % or less. By storing in such an atmosphere, even if oxidation stabilization is performed, oxidation can be slowly performed in a closed container. The lower limit of the oxygen concentration is not particularly limited, but is usually preferably 0.2 volume % or more for oxidation.

[0138] Furthermore, since the gas-stabilized catalyst has a very high hygroscopicity and causes a serious problem in a non-aqueous reaction, it is preferably stored in a sealed container.

[0139] <Purpose>

[0140] Catalyst of the present invention is suitable as the catalyst of reduction reaction, for example, is suitable for the hydrogenation of carboxylic acid and / or carboxylate. That is to say, it is suitable for the manufacture method of following alcohol: make the metal supported catalyst of the present invention contact carboxylic acid and / or carboxylate and reduce carboxylic acid and / or carboxylate to obtain alcohol corresponding to each of the above-mentioned carboxylic acid and / or the above-mentioned carboxylate. As the carboxylic acid or carboxylate of the object of reduction reaction, any carboxylic acid or carboxylate that can be easily obtained industrially can be used.

[0141] When the carboxylic acid and / or carboxylic acid ester that can be subjected to the reduction reaction using the catalyst of the present invention is exemplified, there can be listed: aliphatic chain carboxylic acids such as acetic acid, butyric acid, lauric acid, oleic acid, linoleic acid, linolenic acid, stearic acid, and palmitic acid; aliphatic cyclic carboxylic acids such as cyclohexanecarboxylic acid, cycloalkanecarboxylic acid, and cyclopentanecarboxylic acid; aliphatic polycarboxylic acids such as oxalic acid, malonic acid, succinic acid, methylsuccinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, cyclohexanedicarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,3,4-cyclohexanetricarboxylic acid, dicyclohexyldicarboxylic acid, and decahydronaphthalene dicarboxylic acid; aromatic carboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, and trimesic acid.

[0142] The carboxylic acid is not particularly limited, but is preferably a linear or cyclic saturated aliphatic carboxylic acid, more preferably a carboxylic acid having 20 or less carbon atoms and containing no functional group other than a carboxyl group, and still more preferably a dicarboxylic acid having 20 or less carbon atoms and containing no functional group other than a carboxyl group and represented by formula (2).

[0143] HOOC-R 1 -COOH(2)

[0144] (Where R 1 It may have a substituent and is an aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms excluding the substituent)

[0145] In particular, aliphatic or alicyclic polycarboxylic acids having 4 to 14 carbon atoms or esters thereof are suitable because they have high activity in the reduction reaction and high selectivity.

[0146] In the present invention, it is particularly preferred to use 1,4-cyclohexanedicarboxylic acid or its ester as a reactant to generate the corresponding alcohol by a reduction reaction. That is, a preferred method for producing an alcohol is to use 1,4-cyclohexanedicarboxylic acid or a 1,4-cyclohexanedicarboxylic acid ester (diester) as a raw material, bring the catalyst of the present invention into contact with the raw material, and reduce it.

[0147] When using esters of these carboxylic acids, examples of the alcohol component include lower alcohols such as methanol, ethanol, isopropanol, and n-butanol.

[0148] Alternatively, the esterification may be carried out using the same alcohol as the alcohol obtained by the reduction. In this case, there is an advantage that the alcohol produced in the subsequent hydrogenation reaction does not need to be isolated.

[0149] The reduction reaction using the catalyst of the present invention may be carried out in the absence of a solvent or in the presence of a solvent, and is usually carried out in the presence of a solvent.

[0150] As the solvent, water, lower alcohols such as methanol and ethanol, alcohols of the reaction product, ethers such as tetrahydrofuran, dioxane and ethylene glycol dimethyl ether, hydrocarbons such as hexane and decalin, etc. can be used. These solvents can be used alone or in combination of two or more.

[0151] In particular, when reducing a carboxylic acid, it is preferred to use a solvent containing water for reasons such as solubility.

[0152] The amount of the solvent used is not particularly limited, but is preferably about 0.1 to 20 times by mass, preferably 0.5 to 10 times by mass, and more preferably about 1 to 10 times by mass, based on the carboxylic acid or carboxylic acid ester as a raw material.

[0153] The reduction reaction using the catalyst of the present invention is generally carried out under hydrogen pressure. The reaction is usually carried out at 100 - 300 °C, preferably at 150 - 300 °C. The reaction pressure is 1 - 30 MPa, preferably 1 - 25 MPa, and more preferably 5 - 25 MPa.

[0154] The reduction reaction using the catalyst of the present invention can be carried out in both the liquid phase and the gas phase. However, vaporizing the carboxylic acid / carboxylic acid ester and then carrying out the reduction reaction while maintaining the gas state will make the equipment huge and require a large amount of energy. Therefore, it is preferably carried out in the liquid phase.

[0155] In addition, the hydrogenation method of the carboxylic acid and / or carboxylic acid ester that brings the catalyst of the present invention into contact with the carboxylic acid and / or carboxylic acid ester is also included within the scope of the invention of this application.

[0156] Examples

[0157] Hereinafter, examples are given to illustrate the present invention more specifically. However, the present invention is not limited to the following examples as long as it does not exceed its gist.

[0158] <TPR measurement method>

[0159] Add 0.1 g of the catalyst into a thin quartz tube, and flow 10% H2 / He at 20 ml / min until the hydrogen replacement in the system is completed and the H2 concentration is stable. Then, heat it to 700 °C at a constant rate in 60 minutes. During this period, continuously measure the amount of hydrogen at the outlet using a mass spectrometer and calculate the amount of hydrogen absorbed. <Method for confirming the reaction activity of the catalyst>

[0160] In the present invention, the reaction activity and selectivity of the obtained catalyst are confirmed using the formation reaction of 1,4 - cyclohexanedimethanol (CHDM) based on the hydrogenation reaction of 1,4 - cyclohexanedicarboxylic acid (CHDA).

[0161] In a 200 mL induction stirring autoclave (hereinafter sometimes referred to as a "reactor") made of Hastelloy C (registered trademark), 40 g of water, 10 g of CHDA (a mixture of cis-isomer and trans-isomer: manufactured by Tokyo Chemical Industry Co., Ltd.), and 2 g of the catalyst to be evaluated were placed, and the reactor was replaced with hydrogen, and the hydrogen partial pressure was set to 1 MPa. The reactor was heated under stirring at 1000 rpm (set to a stirring number that would not limit the hydrogen supply rate due to too slow stirring number, and would not cause catalyst cracking due to too high stirring number), and the reaction pressure was set to 8.5 MPa at a specified temperature, and the reaction was started at 240°C. Hydrogen was continuously supplied to the reactor from a hydrogen accumulator, and the reaction was carried out for 3 hours at a fixed temperature of 240°C and 8.5 MPa. After the reaction was completed, the presence or absence of catalyst cracking was visually confirmed. At this time, the apparent reaction rate of the reaction that caused the catalyst cracking became higher, and the selectivity could not be accurately compared, so it was excluded.

[0162] The obtained reaction solution was subjected to neutralization titration with NaOH to obtain the conversion rate of the carboxyl group, and the product was analyzed using a gas chromatograph. The main product was CHDM as the target, and the main by-products were cyclohexanemethanol (CHM) and 4-methylcyclohexanemethanol (MCHM). Except for the above two by-products, the total amount was CHDM, so the catalytic performance was compared by the conversion rate of the carboxyl group and the by-product yield.

[0163] (Comparative Example 1)

[0164] A cylindrical activated carbon carrier (R1 EXTRA manufactured by Cabot Norit Co., Ltd.) having a diameter of 1 mm and a length of 2 to 5 mm was used as a carrier, and a catalyst was prepared by the method of Example 4 of Japanese Patent Publication No. 2001-9277. Specifically, ruthenium chloride hydrate (RuCl3·xH2O), hexachloroplatinic acid (IV) (hexahydrate, etc.) (H2PtCl6·6H2O), and tin (II) chloride (SnCl2·2H2O) were dissolved in a dilute hydrochloric acid solution, and activated carbon treated with nitric acid was added thereto. The solvent was removed therefrom, and the catalyst was dried. The dried catalyst was added to an ammonium bicarbonate solution for treatment, and then filtered, washed, and dried to prepare a metal-supported material. In the method for preparing a metal-supported material, 1.1 ml of 0.3% dilute hydrochloric acid was used for every 1 g of activated carbon used in terms of the dissolved water of the metal chloride. The loading amount of the metal chloride was set to the following amount: when the entire loading amount was loaded, hydrogen reduction was performed, and oxidation stabilization was performed, the metal content in the loaded catalyst was 5.5 mass % of Ru, 2.4 mass % of Pt, and 6.4 mass % of Sn (hereinafter, the loading amount of the metal is all expressed as mass %). In addition, the ammonium bicarbonate used was used in the form of an 11 mass % aqueous solution with a molar amount of chlorine of 1.7 times that of the metal chloride, and 90° C. water was used for washing.

[0165] The obtained metal-supported material was reduced under a hydrogen flow at 500° C. and then oxidatively stabilized under a diluted oxygen atmosphere to prepare a catalyst, which is hereinafter referred to as a “reduced catalyst”.

[0166] The reaction was carried out using the catalyst. The conversion rate and the yield of the by-product are shown in Table 1.

[0167] In addition, in the column of metal types in Table 1, regarding metal types other than ruthenium, platinum, and tin, the compounds used are shown.

[0168] (Comparative Example 2)

[0169] Iron (III) acetylacetonate (Fe(acac)3) was loaded in the reduction catalyst obtained in Comparative Example 1, and after reduction, the catalyst was prepared in a manner in which Fe was loaded in an amount of 0.1% by mass. Specifically, 0.86 ml of tetrahydrofuran solvent was used per 1 g of the reduction catalyst to dissolve a specified amount of Fe(acac)3, and about 10 g of the reduction catalyst obtained in Comparative Example 1 was added, stirred, and allowed to stand for 1 hour. After that, the mixture was evaporated at 80°C under a reduced pressure of 1 kPa for 1 hour, placed in a glass tube, placed in an electric furnace, and dried at 150°C for 2 hours under a circulation of argon 5 L / hour.

[0170] 2.5 g of the dried catalyst was again placed in a glass tube, placed in an electric furnace, and subjected to reduction treatment for 2 hours at 500° C. under a flow of 5 L / hour of hydrogen. Thereafter, the catalyst was cooled under a flow of argon and stabilized under a flow of 6 vol% oxygen / nitrogen at room temperature to obtain a 0.1% Fe-supported catalyst.

[0171] The same reaction as in Comparative Example 1 was carried out using this catalyst (the amount of the catalyst used was such that the amount of the reduction catalyst used in the preparation was 2 g). The results are shown in Table 1.

[0172] (Comparative Example 3)

[0173] In Comparative Example 2, iron (III) chloride hexahydrate (FeCl3·6H2O) was used instead of iron (III) acetylacetonate (Fe(acac)3), and water was used as a solvent. An Fe-supported catalyst was obtained in the same manner as in Example 1 in an amount of 0.2% by mass as Fe metal. Using this catalyst, the same reaction as in Comparative Example 1 was carried out. The results are shown in Table 1.

[0174] (Comparative Example 4)

[0175] A 0.5% Fe-supported catalyst was obtained by the same method as in Comparative Example 2 except that Fe(acac)3 was used so as to be 0.5 mass% in terms of Fe metal. Using this catalyst, the same reaction as in Comparative Example 1 was carried out. The results are shown in Table 1.

[0176] (Comparative Example 5)

[0177] A 0.5% Fe-supported catalyst was obtained by the same method as in Comparative Example 3 except that FeCl3·6H2O was used so as to be 0.5 mass % as Fe metal. Using this catalyst, the same reaction as in Comparative Example 1 was carried out. The results are shown in Table 1.

[0178] (Reference Example 1)

[0179] A 0.2% by mass Cr-supported catalyst was obtained by the same method as in Comparative Example 3, except that chromium (III) chloride hexahydrate (CrCl3·6H2O) was used instead of iron (III) chloride hexahydrate (FeCl3·6H2O). Using this catalyst, the same reaction as in Comparative Example 1 was carried out. The results are shown in Table 1.

[0180] (Reference Example 2)

[0181] A 0.5% Cr-supported catalyst was obtained by the same method as in Comparative Example 2 except that chromium (III) acetylacetonate (Cr(acac)3) was used instead of iron (III) acetylacetonate (Fe(acac)3). Using this catalyst, the same reaction as in Comparative Example 1 was carried out. The results are shown in Table 1.

[0182] (Comparative Example 6)

[0183] In Comparative Example 2, ammonium paramolybdate (ammonium molybdate (VI) tetrahydrate ((NH4)6Mo7O 24 A 0.5% Mo-supported catalyst was obtained by the same method as in Comparative Example 2 except that iron (III) acetylacetonate (Fe(acac)3) was replaced with 4H2O)) and water was used as the solvent. The same reaction as in Comparative Example 1 was carried out using this catalyst. The results are shown in Table 1.

[0184] (Comparative Example 7)

[0185] 1.131 g of RuCl3·xH2O (Ru content 41.9%), 0.547 g of H2PtCl6·6H2O, 0.883 g of SnCl2·2H2O, and 1.196 g of FeCl3·6H2O were dissolved in a 0.3% hydrochloric acid solution. 7.41 g of activated carbon treated with nitric acid as in Comparative Example 1 was added to the solution, stirred thoroughly, and allowed to stand for 3 hours. After 3 hours, it was dried with an evaporator, then moved to a calcination tube, and dried at 150°C for 2 hours under argon flow. The catalyst was added to an 11% by mass aqueous solution of ammonium bicarbonate in an amount of 1.7 equivalents of the total chlorine amount of the metal chloride used, and filtered after treating for 1 hour, washed with water at 90°C, and dried with an evaporator. The dried catalyst was transferred to a calcination tube and dried under argon flow at 150°C. 2.5 g of the dried catalyst was reduced under hydrogen flow at 500°C, and stabilized with 6% oxygen / nitrogen after cooling to prepare a 5.5% Ru-2.4% Pt-5.4% Sn-0.47% Fe / activated carbon (calculated value based on the charge) catalyst (recorded as "FeCl3 together" in Table 1) loaded with four components. Using 2 g of this catalyst, the same reaction as in Comparative Example 1 was carried out. The results are shown in Table 1.

[0186] (Example 1)

[0187] A 0.2%Fe-0.2%Cr supported catalyst was obtained by the same method as in Comparative Example 2 except that FeCl3·6H2O and CrCl3·6H2O were used so that the Fe metal content was 0.2% and the Cr metal content was 0.2% in the reduction catalyst obtained in Comparative Example 1, and water was used as a solvent. Using this catalyst, the same reaction as in Comparative Example 1 was carried out. The results are shown in Table 1.

[0188] (Example 2)

[0189] A 0.4%Fe-0.1%Cr supported catalyst was obtained by the same method as in Comparative Example 2 except that FeCl3·6H2O and CrCl3·6H2O were used so that the Fe metal content was 0.4% and the Cr metal content was 0.1% in the reduction catalyst obtained in Comparative Example 1, and water was used as a solvent. Using this catalyst, the same reaction as in Comparative Example 1 was carried out. The results are shown in Table 1.

[0190] (Example 3)

[0191] FeCl3·6H2O and (NH4)6Mo7O were used in the reduction catalyst obtained in Comparative Example 1 in an amount of 0.2% as Fe metal and 0.2% as Mo metal. 24 ·4H2O, and water was used as the solvent, a 0.2%Fe-0.2%Mo supported catalyst was obtained by the same method as in Comparative Example 2. Using this catalyst, the same reaction as in Comparative Example 1 was carried out. The results are shown in Table 1.

[0192] (Example 4)

[0193] FeCl3·6H2O and ammonium molybdate (VI) tetrahydrate ((NH4)6Mo7O) were used in the reduction catalyst obtained in Comparative Example 1 in an amount of 0.4% as Fe metal and 0.1% as Mo metal. 24 ·4H2O) and a 3% HCl aqueous solution was used as a solvent, a 0.4% Fe-0.1% Mo supported catalyst was obtained by the same method as in Comparative Example 2. Using this catalyst, the same reaction as in Comparative Example 1 was carried out. The results are shown in Table 1.

[0194] [Table 1]

[0195] Table 1

[0196]

[0197]

[0198] As shown in Table 1, the catalyst of the present invention loaded with Fe and Cr and the catalyst of the present invention loaded with Fe and Mo can reduce the yield of cyclohexane methanol (CHM) and 4-methylcyclohexane methanol (MCHM) as main by-products while maintaining a high conversion rate. In contrast, it can be seen that Comparative Examples 2 to 5 loaded with only iron and Comparative Example 6 loaded with only molybdenum have a certain degree of effect compared with the unmodified catalyst not modified with iron or the like, but are inferior to the catalyst of the present invention.

[0199] As described above, it can be seen that the catalyst of the present invention can maintain a high conversion rate and suppress the by-product yield to 60% or less compared to when no catalyst is added, showing an excellent effect.

[0200] Industrial Applicability

[0201] According to the present invention, by adding a plurality of new specific metals to the conventional reduction catalyst combination, the by-product yield is extremely reduced and the target product yield is improved. By extremely reducing the by-product yield, when the by-product is used as a polymer raw material later, the precise purification process can be omitted or simplified, so the present invention is an extremely useful technology in industry.

Claims

1. A metal-supported catalyst, which is a metal-supported catalyst for hydrogenation of carboxylic acid and / or carboxylic ester, in which ruthenium, tin and platinum are supported on a carrier, and the metal-supported catalyst is also supported with iron, chromium and / or molybdenum.

2. The metal-supported catalyst according to claim 1, wherein The amount of iron supported is 0.01% by mass or more and 4% by mass or less, and the total amount of chromium and / or molybdenum supported is 0.01% by mass or more and 2% by mass or less, relative to the total mass of the metal-supported catalyst.

3. The metal supported catalyst according to claim 1 or 2, wherein The carrier is a carbonaceous carrier.

4. The metal supported catalyst according to claim 1 or 2, wherein The total amount of ruthenium, tin, platinum, iron, molybdenum and chromium supported is 5% by mass or more relative to the total mass of the metal-supported catalyst.

5. The metal supported catalyst according to claim 1 or 2, wherein The metal-supported catalyst is prepared by hydrogen reduction.

6. A method for producing an alcohol, comprising contacting the metal supported catalyst according to claim 1 or 2 with a carboxylic acid and / or a carboxylic acid ester and reducing the carboxylic acid and / or the carboxylic acid ester to obtain an alcohol corresponding to each of the carboxylic acid and / or the carboxylic acid ester.

7. A method for hydrogenating a carboxylic acid and / or a carboxylic acid ester, comprising contacting the metal supported catalyst according to claim 1 or 2 with a carboxylic acid and / or a carboxylic acid ester.

8. The method for producing alcohol according to claim 6, wherein The carboxylic acid is 1,4-cyclohexanedicarboxylic acid, and the carboxylic acid ester is 1,4-cyclohexanedicarboxylate.

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