Catalyst for producing allyl acetate and method for producing allyl acetate

Abstract

Provided is a catalyst for producing allyl acetate that shows high activity in an allyl acetate forming reaction and has a low speed of decrease in the specific surface area of a catalyst metal alloy. This catalyst is for use in producing allyl acetate using propylene, acetic acid, and oxygen as raw materials, wherein: (a) palladium, (b) ruthenium, (c) at least one element chosen from the group consisting of copper, nickel, zinc, and cobalt, and (d) an alkali metal salt are supported by (e) a carrier; and the quantity of (b) ruthenium is 20-60 parts by mass relative to 100 parts by mass of (a) palladium.

Description

Catalyst for producing allyl acetate and method for producing allyl acetate

[0001] The present disclosure relates to a catalyst for producing allyl acetate, a method for producing the same, and a method for producing allyl acetate using the catalyst.

[0002] Allyl acetate is an important industrial raw material used as a solvent or a raw material for producing allyl alcohol. One method for producing allyl acetate involves using propylene, acetic acid, and oxygen as raw materials and subjecting them to a gas-phase or liquid-phase reaction to obtain allyl acetate. A catalyst used in this reaction is known and widely used, containing palladium as the main catalyst component and an alkali metal compound and / or alkaline earth metal compound as a promoter component supported on a carrier. For example, Japanese Patent Laid-Open Publication No. 2-91045 (Patent Document 1) discloses a method for producing allyl acetate using a catalyst containing palladium, potassium acetate, and copper supported on a carrier.

[0003] Furthermore, other catalyst components have also been investigated. For example, Japanese Patent Laid-Open Publication No. 52-153908 (Patent Document 2) discloses a method for producing allyl acetate using a catalyst in which activity reduction is suppressed by adding molybdenum in addition to palladium, potassium acetate, and copper.

[0004] Japanese Patent Laid-Open Publication No. 2008-279437 (Patent Document 3) discloses a method for producing allyl acetate using a catalyst in which activity reduction is suppressed by adding gold in addition to palladium, potassium acetate, and copper.

[0005] Japanese Patent Publication No. 7-029980 (Patent Document 4) discloses a method for producing allyl acetate using a catalyst in which palladium, at least one metal selected from copper, lead, ruthenium, and rhenium, and potassium acetate are supported on a carrier. However, with regard to "at least one metal selected from copper, lead, ruthenium, and rhenium," only examples for each individual metal are described, and there are no examples for a combination of two or more metals, such as copper and ruthenium.

[0006] Furthermore, although the reaction is different from that in the case of allyl acetate, for example, JP-A No. 2003-525723 (Patent Document 5) discloses a method for producing a catalyst for vinyl acetate production using ethylene as a starting raw material, in which a palladium salt is supported on a carrier in the first step, a gold salt is supported on a carrier in the second step, and after reduction treatment, copper(II) acetate and potassium acetate are supported on a carrier in the third step, thereby suppressing the generation of carbon dioxide.

[0007] Incidentally, catalyst technology for the production of vinyl acetate has been established for a long time, and attempts have been made to apply and develop catalyst technology for the production of vinyl acetate to catalyst technology for the production of allyl acetate. However, when the reaction raw material was changed from ethylene to propylene, the basic performance of the catalyst was significantly inferior, as described in "Catalysts," Vol. 33, No. 1 (1991), pp. 28-32 (Non-Patent Document 1).

[0008] Japanese Patent Laid-Open No. 2-91045 Japanese Patent Laid-Open No. 52-153908 Japanese Patent Laid-Open No. 2008-279437 Japanese Patent Publication No. 7-029980 Special Publication No. 2003-525723

[0009] "Catalyst", Vol. 33, No. 1 (1991), pp. 28-32

[0010] When using catalysts industrially, they are required to maintain catalytic activity over a long period of time, for example, several thousand hours. However, the specific surface area of ​​precious metal catalysts generally decreases over time, resulting in a decline in catalytic activity. Therefore, the rate at which the specific surface area of ​​a catalyst decreases with reaction is an important factor in industrial use of catalysts, but the above-mentioned literature makes no mention of this.

[0011] The present disclosure provides a catalyst for producing allyl acetate, which exhibits high activity in the allyl acetate production reaction and exhibits a low rate of decrease in the specific surface area of ​​the catalyst metal alloy.

[0012] The present inventors have found that a catalyst for producing allyl acetate, which comprises at least palladium, ruthenium, at least one element selected from copper, nickel, zinc, and cobalt, and an alkali metal salt supported on a carrier, and in which the amount of ruthenium supported is 20 to 60 parts by mass per 100 parts by mass of palladium, is capable of significantly suppressing the rate of decrease in the surface area of ​​the catalytic metal alloy associated with the reaction. They have also found that the catalyst for producing allyl acetate can be obtained by preparing the catalyst using a specific method.

[0013] The present disclosure includes the following aspects [1] to [9]. [1] A catalyst for use in producing allyl acetate using propylene, acetic acid, and oxygen as raw materials, the catalyst comprising (a) palladium, (b) ruthenium, (c) at least one element selected from copper, nickel, zinc, and cobalt, and (d) an alkali metal salt supported on (e) a carrier, wherein the amount of (b) ruthenium is 20 to 60 parts by mass per 100 parts by mass of (a) palladium. [2] The catalyst for producing allyl acetate according to [1], wherein the amount of (b) ruthenium is 25 to 55 parts by mass per 100 parts by mass of (a) palladium. [3] The catalyst for producing allyl acetate according to [1] or [2], wherein the total amount of (c) at least one element selected from copper, nickel, zinc, and cobalt is 5.0 to 150.0 parts by mass per 100 parts by mass of (a) palladium. [4] The catalyst for producing allyl acetate according to any one of [1] to [3], wherein (c) the at least one element selected from copper, nickel, zinc, and cobalt is at least one selected from copper and zinc. [5] The catalyst for producing allyl acetate according to any one of [1] to [4], wherein (d) the alkali metal salt is at least one selected from potassium acetate, sodium acetate, and cesium acetate. [6] The catalyst for producing allyl acetate according to any one of [1] to [5], wherein the mass ratio of the total amount of (a) palladium, (b) ruthenium, (c) the at least one element selected from copper, nickel, zinc, and cobalt, and (d) the alkali metal salt is (a):(b):(c):(d) = 100:20-60:5.0-150.0:157-3920. [7] A method for producing allyl acetate using propylene, acetic acid, and oxygen as raw materials, using the catalyst according to any one of [1] to [6]. [8] A method for producing a catalyst for producing allyl acetate, comprising the following steps:Step 1: A step of preparing a solution of a palladium-containing compound, a ruthenium-containing compound, and a compound having at least one element selected from copper, nickel, zinc, and cobalt, and bringing the solution into contact with a (e) carrier to support the palladium-containing compound, the ruthenium-containing compound, and the compound having at least one element selected from copper, nickel, zinc, and cobalt on the (e) carrier to obtain a supported carrier (A), wherein the ruthenium-containing compound (b) is used in an amount such that the amount of ruthenium is 20 to 60 parts by mass per 100 parts by mass of (a) palladium.Step 2: A step of contacting and impregnating the supported carrier (A) obtained in Step 1 with an alkaline solution (f) to obtain an impregnated carrier (B).Step 3: A step of reducing the impregnated carrier (B) obtained in Step 2 to obtain a metal-supported carrier (C).Step 4: A step of contacting and impregnating the supported carrier (A) obtained in Step 1 with an alkaline solution (f) to obtain an impregnated carrier (B). [9] The method for producing a catalyst for producing allyl acetate according to [8], wherein the compound having at least one element selected from copper, nickel, zinc, and cobalt is copper chloride.

[0014] According to the present disclosure, it is possible to provide a catalyst for producing allyl acetate that exhibits high activity in the allyl acetate production reaction and that reduces the rate of decrease in the specific surface area of ​​the catalyst metal alloy.

[0015] 1 is a graph showing the relationship between the amount of Ru supported and the rate of decrease in MSA in Examples and Comparative Examples.

[0016] Preferred embodiments of the present invention will be described below with reference to the drawings. However, it should be understood that the present invention is not limited to these embodiments and that various applications are possible within the spirit and scope of the present invention. In this disclosure, when "to" is used to describe a numerical range, the numerical values ​​at both ends are the upper and lower limits, respectively, and are included in the numerical range. When multiple upper or lower limits are listed, numerical ranges can be created from all combinations of the upper and lower limits. Similarly, when multiple numerical ranges are listed, separate numerical ranges can be created by individually selecting and combining upper and lower limits from those numerical ranges.

[0017] <Catalyst and Catalyst Production Method> In one embodiment, the catalyst for producing allyl acetate comprises (a) palladium, (b) ruthenium, (c) at least one element selected from copper, nickel, zinc, and cobalt, and (d) an alkali metal salt, supported on (e) a carrier, with the amount of (b) ruthenium being 20 to 60 parts by mass per 100 parts by mass of (a) palladium. The catalyst for producing allyl acetate may optionally support other components. However, preferably, gold is not supported on the catalyst for producing allyl acetate. By using the catalyst for producing allyl acetate of this embodiment, allyl acetate can be obtained with high activity (space-time yield). Furthermore, since the rate of decrease in the specific surface area (MSA) of the catalyst metal alloy after the reaction is small, it is believed that high activity can be maintained over a long period of time. As a result, the production cost of allyl acetate can be reduced, and allyl acetate can be produced efficiently.

[0018] The catalyst for producing allyl acetate is preferably produced by a method comprising the following steps in this order: Step 1: preparing a solution of a palladium-containing compound, a ruthenium-containing compound, and a compound having at least one element selected from copper, nickel, zinc, and cobalt, and (e) contacting the solution with a carrier to obtain a supported carrier (A) by supporting the palladium-containing compound, the ruthenium-containing compound, and the compound having at least one element selected from copper, nickel, zinc, and cobalt on the carrier, provided that the ruthenium-containing compound (b) is used in an amount such that the amount of ruthenium is 20 to 60 parts by mass per 100 parts by mass of palladium (a). Step 2: (f) contacting and impregnating the supported carrier (A) obtained in Step 1 with an alkaline solution to obtain an impregnated carrier (B); Step 3: performing a reduction treatment on the impregnated carrier (B) obtained in Step 2 to obtain a metal-supported carrier (C); and Step 4: (c) contacting and impregnating the supported carrier (A) obtained in Step 1 with an alkaline solution to obtain a metal-supported carrier (C). (d) A step of supporting an alkali metal salt on the metal-supported carrier (C) obtained in step 3. The method for producing a catalyst for producing allyl acetate is not limited to this method, and the order of steps 1 and 2 can be reversed. However, step 3 must be performed after steps 1 and 2. Other steps may be performed before or after each step. These components and steps will be described below.

[0019] (a) Palladium In the present disclosure, (a) palladium may have any valence, but is preferably metallic palladium. Here, "metallic palladium" refers to palladium with a valence of zero. Metallic palladium can usually be obtained by reducing divalent and / or tetravalent palladium ions using a reducing agent such as hydrazine or hydrogen gas. It is preferable that substantially all of (a) palladium is metallic palladium. In the catalyst for producing allyl acetate, not all of the palladium needs to be in a metallic state.

[0020] (a) There are no particular limitations on the raw material for palladium, i.e., the compound containing palladium. Metallic palladium can be used, and a palladium precursor that can be converted into metallic palladium can also be used. In the present disclosure, "a compound containing palladium" also encompasses metallic palladium. Examples of palladium precursors include, but are not limited to, palladium chloride, palladium nitrate, palladium sulfate, sodium chloropalladate, potassium chloropalladate, barium chloropalladate, and palladium acetate. Preferably, sodium chloropalladate is used. Palladium-containing compounds may be used alone or in combination of two or more.

[0021] The mass ratio of (a) palladium to (e) support in the catalyst for producing allyl acetate is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, and even more preferably 1.0 to 3 parts by mass of (a) palladium per 100 parts by mass of the (e) support. This ratio is a calculated value calculated from the amounts of raw materials charged. For example, when a palladium precursor is used as the palladium raw material, the ratio is calculated as the ratio of the mass of palladium element in the palladium precursor used to the mass of the support.

[0022] (b) Ruthenium In the present disclosure, (b) ruthenium may have any valence, but is preferably metallic ruthenium. The "metallic ruthenium" referred to here has a valence of zero. Metallic ruthenium can usually be obtained by reducing trivalent and / or tetravalent ruthenium ions using a reducing agent such as hydrazine or hydrogen gas. It is preferable that substantially all of the (b) ruthenium is metallic ruthenium. In the catalyst for producing allyl acetate, not all of the ruthenium needs to be in a metallic state.

[0023] (b) There are no particular limitations on the ruthenium raw material, i.e., the ruthenium-containing compound. Metallic ruthenium can be used, and a ruthenium precursor that can be converted to metallic ruthenium can also be used. In the present disclosure, "a compound containing ruthenium" also includes metallic ruthenium. Examples of ruthenium precursors include, but are not limited to, ruthenium chloride, carbonyl ruthenium, hexaammineruthenium chloride, ruthenium pentachloride dipotassium, ruthenium pentachloride disodium, ruthenium hexachloride dipotassium, ruthenium hexachloride disodium, and potassium tetraoxoruthenate. Preferably, ruthenium chloride is used. The ruthenium-containing compound may be used alone or in combination of two or more.

[0024] The mass ratio of (b) ruthenium to (e) support in the catalyst for producing allyl acetate is preferably 0.25 to 0.76 parts by mass, more preferably 0.32 to 0.70 parts by mass, and even more preferably 0.38 to 0.63 parts by mass of (b) ruthenium per 100 parts by mass of the (e) support. This ratio is a calculated value calculated from the charged amounts of raw materials. For example, when a ruthenium precursor is used as the ruthenium raw material, the ratio is calculated as the ratio of the mass of ruthenium element in the ruthenium precursor used to the mass of the support.

[0025] The amount of (b) ruthenium in the catalyst for producing allyl acetate is 20 to 60 parts by mass, preferably 25 to 55 parts by mass, and more preferably 30 to 50 parts by mass, per 100 parts by mass of (a) palladium. This ratio is a calculated value calculated from the amounts of raw materials charged. Note that the mass ratio here is the mass ratio of elemental palladium to elemental ruthenium. By setting the amount of ruthenium within the above range, it is possible to achieve both catalytic activity in the allyl acetate production reaction and extended catalyst life. If the amount of (b) ruthenium is less than 20 parts by mass, the catalyst life will be shortened when the reduction rate of the specific surface area of ​​the catalyst metal alloy is used as the evaluation standard. Even if the amount of (b) ruthenium exceeds 60 parts by mass, the effect of extending the catalyst life is small, and excess ruthenium will be wasted, which is economically disadvantageous.

[0026] (c) At least one element selected from copper, nickel, zinc, and cobalt. In the present disclosure, each element in (c) at least one element selected from copper, nickel, zinc, and cobalt may have any valence, but is preferably an element in a metallic state such as metallic copper, metallic nickel, metallic zinc, or metallic cobalt. Here, "metallic element" refers to an element with a valence of zero. Elements in a metallic state can be obtained by reducing a precursor convertible to each metal using a reducing agent such as hydrazine or hydrogen gas. It is preferable that substantially all of (c) at least one element selected from copper, nickel, zinc, and cobalt is an element in a metallic state. In a catalyst for producing allyl acetate, not all of the copper, nickel, zinc, and cobalt need to be in a metallic state.

[0027] (c) The raw material of at least one element selected from copper, nickel, zinc, and cobalt, i.e., the compound containing at least one element selected from copper, nickel, zinc, and cobalt, is not particularly limited. It is possible to use at least one element selected from metallic copper, metallic nickel, metallic zinc, and metallic cobalt, as well as precursors convertible to the metal of each of the elements. In the present disclosure, "a compound containing at least one element selected from copper, nickel, zinc, and cobalt" also encompasses metallic copper, metallic nickel, metallic zinc, and metallic cobalt. Soluble salts of these elements, such as nitrates, carbonates, sulfates, organic acid salts, and halides, can be used as precursors convertible to the metal of each element. Examples of organic acid salts include acetates. Examples of halides include chlorides. Generally, compounds that are readily available and water-soluble are preferred. Preferred precursors include, for example, copper nitrate, copper acetate, nickel nitrate, nickel acetate, zinc nitrate, zinc acetate, cobalt nitrate, cobalt acetate, and copper chloride. Among these, from the viewpoints of raw material stability and availability, at least one selected from copper acetate and copper chloride is preferred, and copper chloride is most preferred. The compound containing at least one element selected from copper, nickel, zinc, and cobalt may be used alone or in combination of two or more.

[0028] (c) The at least one element selected from copper, nickel, zinc, and cobalt is preferably at least one element selected from copper and zinc, and more preferably copper.

[0029] The mass ratio of (c) at least one element selected from copper, nickel, zinc, and cobalt to (e) the support in the catalyst for producing allyl acetate is preferably such that the total amount of (c) at least one element selected from copper, nickel, zinc, and cobalt is 0.05 to 2.0 parts by mass, more preferably 0.1 to 1.0 parts by mass, and even more preferably 0.2 to 0.5 parts by mass, per 100 parts by mass of the (e) support. This ratio is a calculated value calculated from the charged amounts of raw materials. For example, when a chloride is used as a raw material for at least one element selected from copper, nickel, zinc, and cobalt, the ratio is calculated as the ratio of the total mass of copper, nickel, zinc, and cobalt elements in the chloride used to the mass of the support.

[0030] The total amount of (c) at least one element selected from copper, nickel, zinc, and cobalt in the catalyst for producing allyl acetate is preferably 5.0 parts by mass or more, more preferably 8.0 parts by mass or more, and even more preferably 16.0 parts by mass or more, per 100 parts by mass of (a) palladium. The total amount of (c) at least one element selected from copper, nickel, zinc, and cobalt in the catalyst for producing allyl acetate is preferably 150.0 parts by mass or less, more preferably 75.0 parts by mass or less, and even more preferably 40.0 parts by mass or less, per 100 parts by mass of (a) palladium. The total amount of (c) at least one element selected from copper, nickel, zinc, and cobalt in the catalyst for producing allyl acetate is preferably 5.0 to 150.0 parts by mass, more preferably 8.0 to 75.0 parts by mass, and even more preferably 16.0 to 40.0 parts by mass, per 100 parts by mass of (a) palladium. This ratio is a calculated value calculated from the amounts of raw materials charged. The mass ratio here is the mass ratio of elemental palladium to the total amount of at least one element selected from copper, nickel, zinc, and cobalt. By setting the mass ratio within the above range, a good balance between catalytic activity and allyl acetate selectivity in the allyl acetate production reaction can be obtained.

[0031] (d) Alkali Metal Salt In the present disclosure, (d) alkali metal salt is at least one compound selected from alkali metal salts. Examples of alkali metals include lithium, sodium, potassium, rubidium, and cesium, with at least one selected from sodium and potassium being preferred, and potassium being more preferred. Examples of alkali metal salts include hydroxides, acetates, nitrates, and bicarbonates of alkali metals. Specific examples include sodium hydroxide, potassium hydroxide, lithium acetate, sodium acetate, potassium acetate, rubidium acetate, cesium acetate, lithium nitrate, sodium nitrate, potassium nitrate, rubidium nitrate, cesium nitrate, sodium bicarbonate, and potassium bicarbonate. Among these, at least one selected from potassium acetate, sodium acetate, and cesium acetate is preferred, with at least one selected from potassium acetate and cesium acetate being more preferred.

[0032] The mass ratio of the (d) alkali metal salt to the (e) carrier in the catalyst for producing allyl acetate is preferably 2.0 to 50 parts by mass, more preferably 3.0 to 30 parts by mass, and even more preferably 8.0 to 20 parts by mass of the (d) alkali metal salt per 100 parts by mass of the (e) carrier. This ratio is calculated as the ratio of the mass of the alkali metal salt used to the mass of the carrier.

[0033] The amount of (d) alkali metal salt in the catalyst for producing allyl acetate is preferably 157 parts by mass or more, more preferably 200 parts by mass or more, and even more preferably 500 parts by mass or more, per 100 parts by mass of (a) palladium. The amount of (d) alkali metal salt in the catalyst for producing allyl acetate is preferably 3,920 parts by mass or less, more preferably 2,000 parts by mass or less, and even more preferably 1,000 parts by mass or less, per 100 parts by mass of (a) palladium. The amount of (d) alkali metal salt in the catalyst for producing allyl acetate is preferably 157 to 3,920 parts by mass, more preferably 200 to 2,000 parts by mass, and even more preferably 500 to 1,000 parts by mass, per 100 parts by mass of (a) palladium. This ratio is a calculated value calculated from the amounts of raw materials charged. Note that the mass ratio here is the mass ratio between elemental palladium and alkali metal salt. By setting the amount of alkali metal salt within the above range, a good balance between catalytic activity and allyl acetate selectivity in the allyl acetate production reaction can be obtained.

[0034] (e) Support There are no particular restrictions on the (e) support. As the (e) support, a porous substance generally used as a catalyst support can be used. Preferred specific examples include silica, alumina, silica-alumina, diatomaceous earth, montmorillonite, titania, and zirconia, and silica is more preferred. When using an (e) support containing silica as the main component, the silica content of the (e) support is preferably at least 50 mass%, more preferably at least 90 mass%, based on the mass of the (e) support.

[0035] (e) The carrier has a specific surface area of ​​10 to 1000 m as measured by the BET method. ２ / g, and particularly preferably 100 to 500m ２ / g range. (e) The bulk density of the support is preferably in the range of 50 to 1000 g / L, particularly preferably in the range of 300 to 500 g / L. (e) The water absorption rate of the support is preferably in the range of 0.05 to 3 g / g-support, particularly preferably in the range of 0.1 to 2 g / g-support. (e) The pore structure of the support preferably has an average pore diameter in the range of 1 to 1000 nm, particularly preferably in the range of 2 to 800 nm. If the average pore diameter is 1 nm or more, gas diffusion can be facilitated. On the other hand, if the average pore diameter is 1000 nm or less, the specific surface area of ​​the support required to obtain catalytic activity can be ensured.

[0036] Mercury porosimetry and gas adsorption (BJH) method are widely used to measure the pore size distribution of supports. According to the pore classification of IUPAC (International Union of Pure and Applied Chemistry), mercury porosimetry can measure macropores of 50 nm or more and some mesopores of 2 nm to less than 50 nm, while gas adsorption can measure mesopores and micropores of 2 nm or less. An appropriate measurement method can be selected depending on the pore diameter.

[0037] In this disclosure, the water absorption rate of a carrier refers to a value measured by the following measurement method. 1. Accurately weigh out approximately 5 g of carrier on a balance and place in a 100 mL beaker. The mass at this time is designated w1. 2. Approximately 15 mL of ion-exchanged water is added to the beaker so that the carrier is completely covered. 3. Leave to stand for 30 minutes. 4. Remove the supernatant ion-exchanged water from the carrier. 5. Remove the water adhering to the surface of the carrier by gently pressing with a paper towel until the surface is no longer glossy. 6. Accurately weigh the total mass of the carrier and ion-exchanged water. The mass at this time is designated w2. 7. Calculate the water absorption rate of the carrier using the following formula: Water absorption rate (g / g-carrier) = (w2-w1) / w1

[0038] Therefore, the water absorption amount (g) of the carrier is calculated by multiplying the water absorption rate of the carrier (g / g-carrier) by the mass (g) of the carrier used.

[0039] (e) There are no particular limitations on the shape of the carrier. Specific examples include, but are not limited to, powder, spheres, pellets, etc. The optimal shape may be selected depending on the reaction type, reactor, etc. to be used.

[0040] There are no particular restrictions on the particle size of the (e) carrier. When used in a fixed-bed tubular reactor for gas-phase reactions, if the (e) carrier is spherical, the particle diameter is preferably in the range of 1 to 10 mm, more preferably 2 to 8 mm. When a tubular reactor is filled with a catalyst to carry out a gas-phase reaction, a particle diameter of 1 mm or more can prevent an excessive increase in pressure loss during gas flow and enable effective gas circulation. On the other hand, a particle diameter of 10 mm or less can facilitate diffusion of the raw material gas into the catalyst, allowing the catalytic reaction to proceed effectively. There are no particular restrictions on the shape of the carrier. Specific examples include, but are not limited to, powder, spheres, pellets, etc. The optimal shape can be selected depending on the reaction format and reactor used.

[0041] The (f) alkaline solution used in step 2 is not particularly limited, and any alkaline solution can be used. The (f) alkaline solution may be a solution of any alkaline compound. Examples of alkaline compounds include alkali metal or alkaline earth metal hydroxides, alkali metal or alkaline earth metal bicarbonates, alkali metal or alkaline earth metal carbonates, and alkali metal or alkaline earth metal silicates. Preferred alkali metals are lithium, sodium, and potassium, and preferred alkaline earth metals are barium and strontium. Particularly preferred alkaline compounds include sodium metasilicate, potassium metasilicate, sodium hydroxide, potassium hydroxide, and barium hydroxide. Contact with the (f) alkaline solution can convert some or all of the palladium-containing compound, the ruthenium-containing compound, and the compound containing at least one element selected from copper, nickel, zinc, and cobalt into oxides or hydroxides.

[0042] The alkaline compound is suitably used in excess relative to the total of (a) palladium, (b) ruthenium, and (c) at least one element selected from copper, nickel, zinc, and cobalt. For example, the product of the molar amount of the alkaline compound and the valence of the alkaline compound is preferably more than 1.1 times and not more than 3.0 times, more preferably more than 1.5 times and not more than 2.0 times, the sum of the product of the molar amount of palladium element contained in the palladium-containing compound and the valence of palladium, the product of the molar amount of ruthenium element contained in the ruthenium-containing compound and the valence of ruthenium, and the product of the molar amount of at least one element contained in the compound containing at least one element selected from (c) copper, nickel, zinc, and cobalt and the valence of each of the metals.

[0043] The solvent used to form the alkaline compound solution is not particularly limited, and examples thereof include at least one selected from water and alcohol, preferably at least one selected from water, methanol, and ethanol, with water being particularly preferred.

[0044] <Method for Producing a Catalyst for Producing Allyl Acetate> Next, each step of the method for producing a catalyst for producing allyl acetate will be described. Step 1: In this step, a solution of a palladium-containing compound, a ruthenium-containing compound, and a compound having at least one element selected from copper, nickel, zinc, and cobalt is prepared, and the solution is brought into contact with a (e) carrier to support the compound. The compound obtained in this step is called a supported carrier (A). The state of support of these compounds on the (e) carrier is preferably a so-called "eggshell type." When obtaining an eggshell-type supported catalyst, there are no particular limitations on the method for supporting the solution of a palladium-containing compound, a ruthenium-containing compound, and a compound having at least one element selected from copper, nickel, zinc, and cobalt on the (e) carrier, as long as it ultimately results in the production of an eggshell-type supported catalyst. The eggshell type refers to one of the distribution states of active components such as metallic palladium within a support particle or molded body, in which most of the active component is present near the outer surface of the support particle or molded body. Specific examples of the method include a method in which a raw material compound is dissolved in a suitable solvent such as water or acetone, or in an inorganic or organic acid such as hydrochloric acid, nitric acid, or acetic acid, or a solution thereof, and then directly supported on the surface of the support, and an indirect method. Examples of direct support methods include impregnation and spraying. Examples of indirect support methods include, as described below, a method in which a solution of a palladium-containing compound, a ruthenium-containing compound, and a compound having at least one element selected from copper, nickel, zinc, and cobalt is first supported on a support (step 1), and then (f) the internal palladium-containing compound, the ruthenium-containing compound, and the compound having at least one element selected from copper, nickel, zinc, and cobalt are transferred to the surface by contact impregnation with an alkaline solution (step 2), followed by reduction (step 3).

[0045] The (e) carrier can be loaded with a palladium-containing compound, a ruthenium-containing compound, and a compound having at least one element selected from copper, nickel, zinc, and cobalt by preparing a solution of the palladium-containing compound, the ruthenium-containing compound, and a compound having at least one element selected from copper, nickel, zinc, and cobalt, and then impregnating an appropriate amount of the (e) carrier with the solution. More specifically, a solution is prepared by dissolving a palladium-containing compound, a ruthenium-containing compound, and a compound having at least one element selected from copper, nickel, zinc, and cobalt in a suitable solvent such as water or acetone, or a solution containing an inorganic or organic acid such as hydrochloric acid, nitric acid, or acetic acid, and then impregnating the carrier with the solution to obtain the supported carrier (A). Although drying may be performed following the impregnation, it is preferable to proceed to step 2 without the drying step, as this eliminates the need for additional steps.

[0046] Step 2: This step involves contacting and impregnating the supported carrier (A) obtained in Step 1 with an alkaline solution (f) to obtain an impregnated carrier (B). There are no particular limitations on the contact conditions between the supported carrier (A) and the alkaline solution (f), but the contact time is preferably in the range of 0.5 to 100 hours, more preferably 3 to 50 hours. By setting the contact time to 0.5 hours or more, the desired amount of catalyst component can be supported, resulting in sufficient catalytic performance. By setting the contact time to 100 hours or less, deterioration of the carrier can be suppressed.

[0047] The contact temperature is not particularly limited, but is preferably in the range of 10 to 80°C, more preferably in the range of 20 to 60°C. A contact temperature of 10°C or higher allows the conversion reaction to proceed sufficiently. A contact temperature of 80°C or lower can suppress aggregation of palladium, ruthenium, copper, nickel, zinc, and cobalt. The carrier impregnated with the alkaline solution obtained in this step is called the impregnated carrier (B).

[0048] Step 3: This step is a step of subjecting the impregnated carrier (B) obtained in Step 2 to a reduction treatment. The reduction reaction is carried out by contacting the impregnated carrier (B) with a reducing agent or a solution thereof. Either liquid phase reduction or gas phase reduction can be used as the reduction method. The metal-supported carrier obtained in this step is referred to as metal-supported carrier (C).

[0049] Liquid-phase reduction may be carried out in either a non-aqueous system using alcohols or hydrocarbons, or an aqueous system. Examples of reducing agents that can be used include carboxylic acids and their salts, aldehydes, hydrogen peroxide, sugars, polyhydric phenols, boron compounds, amines, and hydrazine. Examples of carboxylic acids and their salts include oxalic acid, potassium oxalate, formic acid, potassium formate, potassium citrate, and ammonium citrate. Examples of aldehydes include formaldehyde and acetaldehyde. Examples of sugars include glucose. Examples of polyhydric phenols include hydroquinone. Examples of boron compounds include diborane and sodium borohydride. Among these, hydrazine, formaldehyde, acetaldehyde, hydroquinone, sodium borohydride, and potassium citrate are preferred, with hydrazine being more preferred.

[0050] When reduction is carried out by the liquid phase method, the temperature is not particularly limited, but the liquid phase temperature is preferably in the range of 0 to 100°C, and more preferably in the range of 10 to 50°C. When the liquid phase temperature is 0°C or higher, a sufficient reduction rate can be obtained. On the other hand, when the liquid phase temperature is 100°C or lower, aggregation of palladium and ruthenium can be suppressed.

[0051] The gas phase reduction is carried out by contacting the impregnated carrier (B) with a reducing gas. The reducing agent used in the gas phase reduction may be, for example, at least one selected from the group consisting of hydrogen gas, carbon monoxide, alcohols, aldehydes, and olefins such as ethylene, propylene, and isobutene. The reducing agent is preferably at least one selected from hydrogen gas and propylene.

[0052] When gas phase reduction is performed, the temperature is not particularly limited, but the impregnated carrier (B) is preferably heated to a range of 30 to 350°C, more preferably to a range of 100 to 300°C. When the heating temperature is 30°C or higher, a sufficient reduction rate can be obtained. On the other hand, when the heating temperature is 300°C or lower, aggregation of palladium and ruthenium can be suppressed.

[0053] The treatment pressure for the gas phase reduction treatment is not particularly limited, but from the viewpoint of equipment, it is preferably in the range of 0.0 to 3.0 MPaG (gauge pressure), and more preferably in the range of 0.1 to 1.0 MPaG (gauge pressure).

[0054] When performing gas phase reduction, the supply rate of the reducing agent is, under standard conditions, a space velocity (hereinafter referred to as SV) of 10 to 15,000 hr. －１ The range is preferably 100 to 8000 hours. －１ It is particularly preferable that the range is:

[0055] Gas-phase reduction may be carried out at any reducing substance concentration, and an inert gas may be added as a diluent, if necessary. Examples of inert gases include helium, argon, and nitrogen gas. Reduction may also be carried out using a reducing agent such as hydrogen gas or propylene in the presence of vaporized water.

[0056] The catalyst before reduction treatment may be packed into a reactor, reduced with propylene gas, and then oxygen and acetic acid may be introduced to produce allyl acetate. In this case, (d) loading of an alkali metal salt in step 4 is carried out between steps 2 and 3.

[0057] The metal-supported carrier (C) may be washed with water as needed. Washing may be carried out continuously or batchwise. The washing temperature is preferably in the range of 5 to 200°C, more preferably in the range of 15 to 80°C. There is no particular limitation on the washing time. It is preferable to select conditions sufficient to remove remaining undesirable impurities. Examples of undesirable impurities include sodium-containing compounds and chlorine-containing compounds. After washing, the metal-supported carrier (C) may be dried by heating as needed.

[0058] Step 4 This step is a step of loading (d) an alkali metal salt onto the metal-loaded carrier (C) obtained in Step 3.

[0059] The (d) alkali metal salt can be supported, for example, by impregnating the metal-supported carrier (C) with a solution containing the required amount of (d) alkali metal salt, followed by drying. The amount of (d) alkali metal salt solution used is preferably 0.9 to 1.0 times the mass of the carrier's water absorption. There are no particular restrictions on the solvent used. Any solvent can be used as long as it has a solubility that allows the (d) alkali metal salt to be dissolved in a solution that is 0.9 to 1.0 times the mass of the carrier's water absorption. The solvent is preferably water.

[0060] There are no particular limitations on the drying temperature and drying time.

[0061] <Catalyst Component Composition> The mass ratio of (a), (b), (c), and (d) in the catalyst for producing allyl acetate is preferably (a):(b):(c):(d)=100:20-60:5.0-150.0:157-3920, and more preferably (a):(b):(c):(d)=100:25-55:8.0-75.0:200-2000. Note that (a), (b), and (c) refer to the mass ratio of the component elements, and (d) refers to the mass ratio of the alkali metal salt.

[0062] The amounts and composition ratios of the metal elements contained in the catalyst for producing allyl acetate in the present disclosure can also be measured by chemical analysis such as inductively coupled plasma emission spectrometry (hereinafter abbreviated as "ICP"), X-ray fluorescence spectrometry (hereinafter abbreviated as "XRF"), or atomic absorption spectrometry.

[0063] As an example of a measurement method, a certain amount of catalyst is crushed in a mortar or the like to obtain a uniform powder, and then the catalyst is added to an acid such as hydrofluoric acid or aqua regia, heated and stirred to dissolve the catalyst into a uniform solution, which is then diluted with pure water to an appropriate concentration and quantitatively analyzed by ICP.

[0064] <Method for producing allyl acetate> Hereinafter, a method for producing allyl acetate using a catalyst for producing allyl acetate will be described. The reaction for producing allyl acetate is preferably carried out in a gas phase using propylene, oxygen, and acetic acid as raw materials. The type of gas phase reaction is not particularly limited and may be a known type. Examples of the type of gas phase reaction include a fixed bed and a fluidized bed. Preferably, it is practically advantageous to employ a fixed bed flow reaction in which a reaction tube is filled with a catalyst for producing allyl acetate.

[0065] The reaction formula is as follows: CH ２ =CHCH ３ +CH ３ COOH + 1 / 2O ２ → CH ２ =CHCH ２ OCOCH ３ +H ２ O

[0066] The feed gas supplied to the reactor contains propylene, oxygen gas, and gaseous acetic acid, and may further contain nitrogen gas, carbon dioxide, a rare gas, or the like as a diluent, as necessary. When propylene, acetic acid, and oxygen are defined as the reaction raw materials, the ratio of the reaction raw materials to the diluent, in terms of molar ratio, is preferably reaction raw materials:diluent=1:0.05-9, and more preferably reaction raw materials:diluent=1:0.1-3. The ratio of acetic acid, propylene, and oxygen in the feed gas, in terms of molar ratio, is preferably acetic acid:propylene:oxygen=1:1-12:0.5-2.

[0067] In the reaction for producing allyl acetate, the presence of water in the reaction system is significantly effective in maintaining the activity of the catalyst and in promoting the production of allyl acetate. The raw material gas preferably contains 0.5 to 23 mol % or 0.5 to 20 mol % of water vapor.

[0068] It is preferable to use high-purity propylene as the reaction raw material, but it may be contaminated with lower saturated hydrocarbons such as methane, ethane, and propane.

[0069] Oxygen can be supplied in the form of air diluted with an inert gas such as nitrogen gas or carbon dioxide gas. However, when the reaction gas is circulated, it is generally advantageous to use a high-concentration oxygen gas, preferably an oxygen gas with a purity of 99 mol % or more.

[0070] The reaction raw materials, propylene and acetic acid, may be produced from fossil fuels, biomass, or a mixture thereof. The concentration of C carbon atoms in propylene, acetic acid, and allyl acetate is 1×10 relative to the total number of carbon atoms. －１４ ~2 x 10 －１２ may be.

[0071] There are no particular restrictions on the material of the reactor, but it is preferable that the material be corrosion-resistant.

[0072] There is no particular limitation on the reaction temperature. The reaction temperature is preferably in the range of 100 to 300°C, more preferably in the range of 120 to 250°C. The reaction pressure is not particularly limited, although it is practically advantageous from the viewpoint of equipment to be in the range of 0.0 to 3.0 MPaG (gauge pressure). The reaction pressure is more preferably in the range of 0.1 to 1.5 MPaG (gauge pressure).

[0073] When the reaction is carried out in a fixed bed flow reactor, the raw material gas is reacted at a rate of SV = 10 to 15,000 hr under standard conditions. －１ It is preferable that the catalyst is supplied in the range of 300 to 8000 hr. －１ It is more preferable that the amount of the catalyst be in the range of 1000 to 15000 kJ / kg.

[0074] The present invention will be further explained below with reference to examples and comparative examples, but the present invention is not limited to these descriptions in any way.

[0075] Example 1: Preparation of Catalyst A A commercially available silica spherical carrier (sphere diameter 5 mm, specific surface area 155 m) was used as the carrier. ２ / g, water absorption rate 0.85 g / g-carrier, bulk density 473 g / L, water absorption amount 402 g / L, hereinafter simply referred to as "silica carrier"), a catalyst was produced by the following procedure.

[0076] Step 1: Sodium chloropalladate (Na ２ PdCl ４ ) aqueous solution 30.0 g, ruthenium chloride (RuCl ３ ) 3.69 g, and copper chloride dihydrate (CuCl ２ ・2H ２ 4.83 g of sodium metasilicate nonahydrate was added and the mixture was diluted to 394 mL with pure water. 1 L of the silica carrier was added to this, and the entire amount was absorbed to obtain a metal-supported carrier (A-1). Step 2: 82.7 g of sodium metasilicate nonahydrate was dissolved in pure water and the mixture was diluted to 804 mL. The metal-supported carrier (A-1) obtained in step 1 was immersed in this and allowed to stand at room temperature for 20 hours to obtain an impregnated carrier (B-1) impregnated with the sodium metasilicate solution. Step 3: 98.5 g of hydrazine monohydrate was added to the slurry of the impregnated carrier (B-1) obtained in step 2, and the mixture was gently stirred and then allowed to stand at 25°C for 4 hours. The reduced impregnated carrier (B-1) was filtered and then transferred to a glass column equipped with a stopcock and washed by passing pure water through it for 40 hours. Next, it was dried at 110°C for 4 hours under an air stream to obtain a metal-supported carrier (C-1). Step 4: 52 g of potassium acetate was dissolved in pure water and the volume was adjusted to 362 mL. The metal-supported carrier (C-1) obtained in Step 3 was added to the solution and absorbed completely. The solution was then dried at 110°C for 4 hours under an air stream to obtain a catalyst A for producing allyl acetate.

[0077] Example 2 Preparation of Catalyst B Catalyst B was prepared by repeating the procedure of Example 1, except that the amount of ruthenium chloride was changed from 3.69 g to 4.31 g, the amount of sodium metasilicate nonahydrate was changed from 82.7 g to 86.1 g, and the amount of hydrazine monohydrate was changed from 98.5 g to 102.5 g.

[0078] Example 3 Preparation of Catalyst C Catalyst C was prepared by repeating the procedure of Example 1, except that the amount of ruthenium chloride was changed from 3.69 g to 6.16 g, the amount of sodium metasilicate nonahydrate was changed from 82.7 g to 96.2 g, and the amount of hydrazine monohydrate was changed from 98.5 g to 114.6 g.

[0079] Comparative Example 1 Preparation of Comparative Catalyst D Comparative catalyst D was prepared by repeating the procedure of Example 1, except that the amount of ruthenium chloride was changed from 3.69 g to 2.05 g, the amount of sodium metasilicate nonahydrate was changed from 82.7 g to 73.2 g, and the amount of hydrazine monohydrate was changed from 98.5 g to 87.8 g.

[0080] Comparative Example 2 Preparation of Comparative Catalyst E Comparative catalyst E was prepared by repeating the procedure of Example 1, except that the amount of ruthenium chloride was changed from 3.69 g to 0.62 g, the amount of sodium metasilicate nonahydrate was changed from 82.7 g to 65.8 g, and the amount of hydrazine monohydrate was changed from 98.5 g to 78.4 g.

[0081] Comparative Example 3: Preparation of Comparative Catalyst F Comparative catalyst F was prepared by repeating the procedure of Example 1, except that ruthenium chloride was not added, the amount of sodium metasilicate nonahydrate was changed from 82.7 g to 62.5 g, and the amount of hydrazine monohydrate was changed from 98.5 g to 74.4 g.

[0082] Comparative Example 4: Preparation of Comparative Catalyst G. Step 1: 30.3 g of an aqueous solution of sodium chloropalladate adjusted to have a palladium content of 19.8% by mass and 30.3 g of an aqueous solution of sodium chloropalladate adjusted to have a gold content of 20% by mass were used. ４) aqueous solution was mixed and the volume was adjusted to 382 mL with pure water. 1 L of silica carrier (bulk density 473 g / L, water absorption 402 g / L) was added to this, and the entire amount was absorbed to obtain a supported carrier (A-7). Step 2: 34.6 g of sodium metasilicate nonahydrate was added and dissolved in pure water, and the volume was adjusted to 803 mL. The supported carrier (A-7) obtained in Step 1 was immersed in this and allowed to stand at room temperature for 20 hours to obtain an impregnated carrier (B-7) impregnated with the sodium metasilicate solution. Step 3: 26.3 g of hydrazine monohydrate was added to the slurry of impregnated carrier (B-7) obtained in Step 2, and after gentle stirring, the mixture was allowed to stand at 25°C for 4 hours. The reduced impregnated carrier (B-7) was filtered and transferred to a glass column equipped with a stopcock, and washed by passing pure water through it for 40 hours. Next, drying was carried out under an air stream at 110°C for 4 hours to obtain a metal-supported carrier (C-7). Step 4: Pure water was added to 52 g of potassium acetate and 7.53 g of copper acetate monohydrate to dissolve them, and the volume was adjusted to 361 mL. The metal-supported carrier (C-7) obtained in step 3 was added to this and absorbed entirely. Next, drying was carried out under an air stream at 110°C for 4 hours to obtain a comparative catalyst G for producing allyl acetate.

[0083] Examples 4 to 6, Comparative Examples 5 to 8 10.5 mL of each of Catalysts A to C and Comparative Catalysts D to G obtained in Examples 1 to 3 and Comparative Examples 1 to 4 was uniformly diluted with 31.5 mL of silica carrier and then packed into a reaction tube (made of SUS316L, inner diameter 25 mm). A gas mixture with a molar ratio of propylene:oxygen:acetic acid:water:nitrogen=35:6:8.0:23:28.0 was introduced at a space velocity of 2070 h under conditions of a reaction temperature of 150°C and a reaction pressure of 0.75 MPaG (gauge pressure). －１ The reaction mixture was introduced into the reaction tube at 100° C., and a reaction was carried out to obtain allyl acetate from propylene, oxygen, and acetic acid. After 150 hours had passed from the start of the reaction, the reaction product was analyzed.

[0084] The reaction was analyzed by cooling the entire outlet gas that had passed through the catalyst packed bed, recovering the entire condensed reaction liquid, and analyzing it by gas chromatography. The total amount of uncondensed gas that flowed out during the sampling period was measured, and a portion of it was taken and analyzed by gas chromatography.

[0085] The condensed reaction solution was analyzed as follows. Using the internal standard method, 1 g of 1,4-dioxane was added to 6 g of the reaction solution as an internal standard to prepare an analytical solution, and 0.3 μL of this solution was injected and analyzed under the following conditions: Gas chromatography: Shimadzu Corporation GC-14B Detector: FID (H ２ Pressure 60 kPaG, air pressure 60 kPaG) Column: Capillary column TC-WAX (length 30 m, inner diameter 0.25 mm, film thickness 0.25 μm) Carrier gas: Nitrogen gas (flow rate 30 mL / min) Temperature conditions: Detector temperature and vaporization chamber temperature 200°C, column temperature held at 40°C for 10 minutes from the start of analysis, then heated to 130°C at a heating rate of 7°C / min and held at 130°C for 20 minutes, then heated to 200°C at a heating rate of 20°C / min and held at 200°C for 5 minutes

[0086] Analysis of uncondensed gas was performed using the absolute calibration curve method, with 100 mL of effluent gas collected and the entire volume passed through a 2 mL gas sampler attached to the gas chromatograph under the following conditions: Gas chromatograph: Shimadzu Corporation GC-14B Column: Unibeads IS 60 / 80 mesh (3 mm diameter x 3 m) Carrier gas: Helium (flow rate 20 mL / min) Temperature conditions: Detector temperature 160°C, vaporizer temperature 150°C, column temperature constant 145°C Detector: TCD (He pressure 600 kPaG, Current 100 mA)

[0087] The activity of the catalyst was calculated as the mass of allyl acetate produced per hour per liter of catalyst volume (space time yield: STY, unit: g / L-cat·hr).

[0088] The selectivity of allyl acetate was calculated by the following formula: Allyl acetate selectivity (based on propylene) (%) = [Amount of allyl acetate produced (mol) / Amount of propylene consumed (mol)] x 100

[0089] <Measurement of Specific Surface Area of ​​Catalytic Metal> The specific surface area (Metal Specific Surface Area, hereinafter abbreviated as "MSA") of the catalytic metal alloy (Pd, Ru, Cu, and Au) supported on the catalyst for producing allyl acetate was measured using a fully automatic catalytic gas adsorption analyzer (Ohkura Riken R6015). Specifically, approximately 1.2 g of catalyst was sampled before and after the allyl acetate synthesis reaction and filled into an H-shaped glass cell dedicated to the apparatus, and the glass cell was connected to a CO adsorption analyzer. As a pretreatment for the specific surface area measurement, a hydrogen reduction treatment was performed by flowing hydrogen gas through the glass cell at 0.03 L / min for 1 hour, raising the temperature to 40°C at 10°C / min, and holding it at 40°C for 1 hour. The hydrogen reduction treatment was performed to reduce the metal species exposed on the alloy surface to a metallic state, thereby promoting CO gas adsorption. Since the temperature of the hydrogen reduction treatment is near room temperature, the change in the specific surface area due to the aggregation of the catalyst metal alloy can be ignored.

[0090] Next, a fixed amount (1.136 mL) of 100% CO gas was intermittently supplied to the glass cell in pulses 10 times at 10-minute intervals. The amount of unadsorbed CO gas was detected by a TCD detector, and the amount of CO adsorbed on the alloy surface was calculated.

[0091] Based on the assumption that Pd, Ru, Cu, and Au are randomly exposed on the surface of the catalyst metal alloy and that CO gas is adsorbed on this surface, the MSA of the catalyst metal alloy was calculated from the amount of CO adsorption.

[0092] An index of the degree of change in MSA before and after the reaction of a catalyst for producing allyl acetate (hereinafter abbreviated as "MSA reduction rate") was calculated from the measured values ​​of MSA before and after the reaction. The MSA reduction rate was calculated using the following formula: MSA reduction rate (%) = 100 - [MSA after reaction (m ２ / g) / MSA before reaction (m ２ / g)] x 100

[0093] A large MSA means a large number of Pd sites for adsorbing CO. Therefore, there is a strong correlation between MSA and catalytic activity, and it is presumed that if the rate of decrease in MSA after reaction is small, the catalyst will have a long life.

[0094] The results of Examples 4 to 6 and Comparative Examples 5 to 8 are shown in Table 1 and Figure 1. From Table 1, it can be said that the catalysts of the Examples generally have higher activity for allyl acetate production than the catalysts of the Comparative Examples, and that the allyl acetate selectivity is also equivalent to that of the Comparative Examples. Furthermore, since the catalysts of the Examples have a smaller rate of decrease in MSA after the reaction than the Comparative Examples, it is presumed that the decrease in the surface area of ​​the catalyst metal alloy during the reaction is suppressed and that the catalysts have a longer life than the catalysts of the Comparative Examples.

[0095]

Claims

1. A catalyst for producing allyl acetate using propylene, acetic acid, and oxygen as raw materials, comprising (a) palladium, (b) ruthenium, (c) at least one element selected from copper, nickel, zinc, and cobalt, and (d) an alkali metal salt, supported on (e) a carrier, and the amount of (b) ruthenium is 20 to 60 parts by mass per 100 parts by mass of (a) palladium.

2. The catalyst for producing allyl acetate according to claim 1, wherein the amount of (b) ruthenium is 25 to 55 parts by mass per 100 parts by mass of (a) palladium.

3. The catalyst for producing allyl acetate according to claim 1 or 2, wherein the total amount of (c) at least one element selected from copper, nickel, zinc, and cobalt is 5.0 to 150.0 parts by mass per 100 parts by mass of (a) palladium.

4. A catalyst for producing allyl acetate according to claim 1 or 2, wherein (c) at least one element selected from copper, nickel, zinc and cobalt is at least one element selected from copper and zinc.

5. The catalyst for producing allyl acetate according to claim 1 or 2, wherein (d) the alkali metal salt is at least one selected from potassium acetate, sodium acetate and cesium acetate.

6. The catalyst for producing allyl acetate according to claim 1 or 2, wherein the mass ratio of the total amount of (a) palladium, (b) ruthenium, (c) at least one element selected from copper, nickel, zinc, and cobalt, and (d) alkali metal salt is (a):(b):(c):(d)=100:20-60:5.0-150.0:157-3920.

7. A method for producing allyl acetate using propylene, acetic acid and oxygen as raw materials, which uses the catalyst according to claim 1 or 2.

8. A method for producing a catalyst for producing allyl acetate, comprising the steps of: Step 1: A step of preparing a solution of a palladium-containing compound, a ruthenium-containing compound, and a compound having at least one element selected from copper, nickel, zinc, and cobalt, and contacting the solution with a (e) carrier to support the palladium-containing compound, the ruthenium-containing compound, and the compound having at least one element selected from copper, nickel, zinc, and cobalt on the (e) carrier to obtain a supported carrier (A), wherein the ruthenium-containing compound is used in an amount such that the amount of ruthenium (b) is 20 to 60 parts by mass per 100 parts by mass of palladium (a). Step 2: A step of contacting and impregnating the supported carrier (A) obtained in Step 1 with an alkaline solution (f) to obtain an impregnated carrier (B). Step 3: A step of reducing the impregnated carrier (B) obtained in Step 2 to obtain a metal-supported carrier (C). Step 4: A step of (d) supporting an alkali metal salt on the metal-supported carrier (C) obtained in Step 3.

9. The method for producing a catalyst for producing allyl acetate according to claim 8, wherein the compound containing at least one element selected from copper, nickel, zinc and cobalt is copper chloride.

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