JP2022090478A - Method for producing catalyst for producing hydrogen peroxide by anthraquinone method - Google Patents

Abstract

To provide a method for producing a catalyst for producing hydrogen peroxide by an anthraquinone method, and in which the catalyst has excellent performance, and the establishment of the production method is desired.SOLUTION: The present invention provides a production method, which is a method for producing a catalyst for producing hydrogen peroxide by an anthraquinone method, and in which a carrier or a catalyst in which a transition metal is supported on the carrier is treated with an alkaline aqueous solution having a pH of 12 or higher.SELECTED DRAWING: None

Description

The present invention relates to a method for producing a catalyst for producing hydrogen peroxide by the anthraquinone method, and more particularly to a method for producing a catalyst for producing hydrogen peroxide by the anthraquinone method, which has a reduced boron content.

Currently, the main industrial method for producing hydrogen peroxide is an anthraquinone method using anthraquinone, tetrahydroanthraquinone, alkylanthraquinone or alkyltetrahydroanthraquinone (hereinafter, collectively referred to as anthraquinones) as a reaction medium. Is. Anthraquinones are usually used in a state of being dissolved in two kinds of mixed solvents, a polar organic solvent and a non-polar organic solvent. A solution prepared by dissolving anthraquinones in this mixed solvent is called a working solution (WS).

The anthraquinone method mainly consists of a hydrogenation step, an oxidation step and an extraction step. In the hydrogenation step, hydrogenation treatment is carried out in which anthraquinones in the working solution are hydrogenated in the presence of a catalyst to produce corresponding anthraquinones. In the subsequent oxidation step, the obtained anthrahydroquinones are oxidized with air or a gas containing oxygen and returned to the anthraquinones. At this time, hydrogen peroxide is generated and dissolved in the working solution. In the subsequent extraction step, the generated hydrogen peroxide is extracted with water and separated from the working solution. As shown in FIG. 1, the working solution after the extraction step is returned to the hydrogenation step again and is continuously used in the oxidation step, the extraction step, and so on.

As the process of producing hydrogen peroxide is repeated, anthraquinone derivatives such as anthraquinones are produced by side reactions in the working solution. Although the amount of by-product of the anthraquinone derivative is very small per pass, it accumulates in the working solution as the hydrogen peroxide production process is repeated, causing various disorders. Therefore, when the anthraquinone method is continuously carried out, as shown in FIG. 1, a regeneration step of extracting a part of the working solution after the extraction step and before the hydrogenation step and regenerating the working solution is also performed.

Regarding the catalyst for producing hydrogen peroxide used in the anthraquinone method, Patent Documents 1 to 3 disclose a method for regenerating a catalyst deteriorated by continuously carrying out the anthraquinone method. However, a method for enhancing the performance of the catalyst itself is not disclosed.

JP-A-2007-314400 JP-A-2007-297248 JP-A-47-0233386

It is desired to establish a method for producing a catalyst having excellent performance, which is a catalyst for producing hydrogen peroxide by the anthraquinone method.

The present invention may provide the following aspects.
[1] A method for producing a catalyst for producing hydrogen peroxide by the anthraquinone method.
A production method for treating a carrier or a catalyst in which a transition metal is supported on the carrier with an alkaline aqueous solution having a pH of 12 or higher.
[2] The production method according to the above [1], wherein the concentration of the alkaline aqueous solution is 0.01 to 10% by mass.
[3] The production method according to the above [1] or [2], wherein the alkaline aqueous solution is a strong base aqueous solution.
[4] The production method according to the above [3], wherein the strong base aqueous solution is at least one selected from the group consisting of a sodium hydroxide aqueous solution, a potassium hydroxide aqueous solution and a sodium carbonate aqueous solution.
[5] The production method according to any one of the above [1] to [4], which is treated at 20 to 100 ° C.
[6] The production method according to any one of [1] to [5] above, wherein the catalyst for producing hydrogen peroxide is a hydrogenation reaction catalyst or a regeneration catalyst.
[7] The production method according to any one of [1] to [6] above, wherein the transition metal is at least one selected from the group consisting of palladium, rhodium, ruthenium, platinum and nickel.
[8] The carrier to be treated is at least one carrier selected from the group consisting of alumina, alumina magnesia, silica and silica-alumina, or a composite carrier of the carrier and an alkaline earth metal oxide. The production method according to any one of the above [1] to [7].
[9] The production method according to the above [8], wherein the alkaline earth metal oxide is at least one selected from the group consisting of MgO, CaO, BaO and SrO.
[10] The production method according to any one of the above [1] to [9], wherein the pH of the alkaline aqueous solution is 13 to 14.
[11] The production method according to any one of [1] to [10] above, wherein the carrier or catalyst is an unused carrier or catalyst.
[12] The production method according to any one of [1] to [11] above, wherein the treatment is performed at a temperature higher than 60 ° C and lower than 100 ° C.
[13] The production method according to any one of [1] to [12] above, wherein the concentration of the alkaline aqueous solution is 0.1% by mass or more and less than 0.5% by mass.
[14] A catalyst for producing hydrogen peroxide, wherein a transition metal is supported on a carrier and the boron content is 0.001% by mass or less.
[15] A method for producing hydrogen peroxide using the catalyst for producing hydrogen peroxide according to the above [14] in the anthraquinone method.

According to the present invention, by removing the boron component contained in the carrier or the catalyst, it is possible to produce a catalyst having excellent performance with less adverse effect on the hydrogen peroxide production process. Further, hydrogen peroxide can be produced by the anthraquinone method using a catalyst having excellent performance.

The manufacturing process of hydrogen peroxide by the anthraquinone method is shown. The relationship between pH and the amount of boron elution in Comparative Examples 1 to 6 and Examples 1 to 5 is shown. The relationship between pH and the amount of boron elution in Examples 6 to 8 and Comparative Example 7 is shown. The relationship between the washing temperature and the amount of boron elution in Examples 6 to 8 is shown.

Method for Producing Hydrogen Peroxide Production Catalyst by Anthraquinone Method One aspect of the present invention relates to a method for producing a hydrogen peroxide production catalyst by the anthraquinone method (hereinafter, may be referred to as the production method of the present invention). In the production method of the present invention, a carrier or a catalyst in which a transition metal is supported on the carrier is treated with an alkaline aqueous solution.

The carrier to be treated is not particularly limited, and is, for example, silica, silica-alumina, alumina, titania, zirconia, alumina-magnesia, magnesia, silica-titania, zeolite, activated carbon, organic polymer, silica-alumina composite oxide, silica-titania. Examples include composite oxides, alumina-titania composite oxides, and physical mixtures thereof. Further, the carrier to be treated may be a composite carrier of the above carrier and an alkaline earth metal oxide.

Preferably, the carrier to be treated is at least one carrier selected from the group consisting of alumina, alumina magnesia, silica and silica-alumina, or a composite carrier of the carrier and an alkaline earth metal oxide. As the alkaline earth metal, at least one selected from the group consisting of MgO, CaO, BaO and SrO is preferable.

More preferably, the carrier to be treated is alumina magnesia.

The ratio of magnesia in alumina / magnesia is preferably 1 to 20% by mass, more preferably 5 to 15% by mass.

The particle size, particle shape, and total pore volume of the carrier to be treated are not particularly limited and can be appropriately selected depending on the shape of the reactor using the hydrogenation reaction catalyst or the regeneration catalyst.

Examples of the particle shape include amorphous, spherical, cylindrical, trefoil, four-leaf, and ring.

For example, in the case of a mechanical stirring type or suspension bubble column type reactor, the particle shape of the carrier to be treated is usually preferably amorphous or spherical. For fixed-bed hydrogenation reactors or regeneration reaction vessels, spherical particles or crushed particles are preferred, and pellets are more preferred.

The particle size is preferably 1 μm to 10 mm in median diameter. For example, in the case of a mechanical stirring type or suspension bubble column type reactor, the median diameter of the carrier to be treated is usually preferably 1 to 200 μm, more preferably 20 to 180 μm, and 30 to 150 μm. It is more preferable to have. For a fixed-bed hydrogenation reactor or a regeneration reaction vessel, the median diameter is preferably 0.1 to 10 mm, more preferably 0.5 to 3 mm.

When the median diameter is small, for example, 1 to 200 μm, it can be analyzed by a laser diffraction / scattering method. When the value is large, for example 0.1 to 10 mm, it can be measured by analysis of a microscope image.

The total pore volume is preferably 0.2 to 2.0 ml / g.

The total pore volume can be measured by the BET method.

The transition metal is preferably at least one selected from the group consisting of palladium, rhodium, ruthenium, platinum and nickel. The transition metal may be a simple substance or a compound. As the compound, an oxide is suitable from the viewpoint that it is easily reduced to a metal under reaction conditions. The transition metal is preferably a simple substance or an oxide.

The transition metal is usually preferably supported in an amount of 0.1 to 10% by mass, more preferably 0.1 to 5% by mass, based on the carrier. It is particularly preferred that it be supported in an amount of mass%.

The carrier to be treated or the catalyst to be treated may be unused or used for producing hydrogen peroxide by the anthraquinone method, but it is preferably unused.

The alkali metal contained in the alkaline aqueous solution may be any alkali metal of Group Ia of the periodic table. Examples of the alkali metal salt used for preparing the alkaline aqueous solution include LiOH, NaOH, Na ₂ CO ₃ , NaHCO ₃ , Na ₂ B ₄ O ₇ , Na ₄ P ₂ O ₆ , NaBO ₂ , NaNO ₂ , NaBO ₃ , and Na. ₂ HPO ₄ , Na ₃ PO ₄ , Na ₂ SiO ₃ , Na ₆ Si ₂ O ₇ , Na ₂ Si ₃ O ₇ , Na ₂ SnO ₃ , Na ₂ S, Na ₂ S ₂ O ₃ , Na ₂ WO ₃ , Al ₂ K ₂ O ₄ , KOH, BH ₄ K, K ₂ CO ₃ , KCN, KNO ₂ , C ₆ H ₅ OK, K ₂ HPO ₄ , K ₃ PO ₄ , K ₄ P ₂ O ₇ , K ₂ SnO ₃ , Examples thereof include K ₁₈ H ₃₅ O ₂ , K ₃ SbS ₄ , and C ₃ H ₅ KS ₂ O.

The alkaline aqueous solution is preferably a strong base aqueous solution, and more preferably at least one selected from the group consisting of a sodium hydroxide aqueous solution, a potassium hydroxide aqueous solution and a sodium carbonate aqueous solution.

The pH of the alkaline aqueous solution is 12 or more, preferably 13 to 14. If the pH is excessively low, boron contained in the carrier or catalyst to be treated may not be sufficiently removed.

The concentration of the alkaline aqueous solution is appropriately determined so that the pH is in the above range, but the lower limit is preferably 0.01% by mass, more preferably 0.1% by mass. The upper limit is preferably 10% by mass, more preferably 5% by mass, still more preferably less than 1% by mass, and particularly preferably less than 0.5% by mass. Suitable numerical ranges for the concentration of the alkaline aqueous solution are 0.01 to 10% by mass, 0.01 to 5% by mass, 0.01% by mass or more and less than 1% by mass, and 0.01% by mass or more and less than 0.5% by mass. , 0.1 to 10% by mass, 0.1 to 5% by mass, 0.1% by mass or more and less than 1% by mass, or 0.1% by mass or more and less than 0.5% by mass.

When a used catalyst is used as the treatment target, it may be washed with a non-polar organic solvent or a solvent used for the working solution in advance, and then dried or washed with water.

In the production method of the present invention, a carrier or a catalyst in which a transition metal is supported on a carrier is treated with an alkaline aqueous solution. The treatment is carried out by putting the carrier or the catalyst into an alkaline aqueous solution and contacting them for a certain period of time. At this time, it is preferable to perform stirring. The stirring speed is not particularly limited and can be appropriately determined depending on the size of the reaction system and the like.

The temperature of the alkaline aqueous solution at the time of treatment is preferably 20 to 100 ° C., 20 to 90 ° C., higher than 30 ° C. and 100 ° C. or lower, 60 to 100 ° C. or higher than 60 ° C. and lower than 100 ° C. Alternatively, in another preferred embodiment, 60 ° C. or higher is preferable. If the heating temperature is excessively low, the efficiency of removing the boron component may decrease.

The treatment time is not particularly limited and can be appropriately determined depending on the size of the reaction system and the like, but is preferably about 1 minute or longer, more preferably 30 minutes or longer, still more preferably 30 minutes to 1 hour. ..

The carrier or catalyst after treatment with the alkaline aqueous solution may be separated from the alkaline aqueous solution by filter filtration or the like, and post-treatment such as washing or drying may be performed as necessary.

When the carrier is treated, the transition metal described above is then supported by a known method to obtain a catalyst for producing hydrogen peroxide by the anthraquinone method.

Thus, the catalyst used for the production of hydrogen peroxide by the anthraquinone method can be produced. In the catalyst obtained by the production method of the present invention, the content of the boron component, which was conventionally contained as an impurity, is reduced. Therefore, it is possible to reduce the adverse effect of the boron component on the manufacturing process of hydrogen peroxide.

The catalyst obtained by the production method of the present invention can be used as a hydrogenation reaction catalyst in a hydrogenation step (also referred to as a hydrogenation reaction step) of the anthraquinone method, or can be used as a regeneration catalyst in a regeneration step. It is preferable to use it as a regeneration catalyst.

Hydrogen peroxide production catalyst Another aspect of the present invention is a hydrogen peroxide production catalyst in which a transition metal is supported on a carrier and the boron content is low (hereinafter, may be referred to as a catalyst of the present invention). The present invention preferably relates to a catalyst for producing hydrogen peroxide by the anthraquinone method. Preferably, the catalyst of the present invention is produced by the production method of the present invention.

The boron content is preferably 0.001% by mass or less. The lower limit is 0.000% by mass or more, and more preferably greater than 0.000% by mass.

When such a catalyst having a low boron content is used in the production of hydrogen peroxide by the anthraquinone method, particularly in the hydrogen peroxide step or the regeneration step, it is possible to prevent the boron component from being mixed in the produced hydrogen peroxide.

The details of the "carrier" and the "transition metal" in the catalyst of the present invention are as described in the section "Method for producing a catalyst for producing hydrogen peroxide by the anthraquinone method".

Production of Hydrogen Peroxide by Anthraquinone Method Another aspect of the present invention is a method for producing hydrogen peroxide using the catalyst of the present invention in the anthraquinone method (hereinafter, referred to as the method for producing hydrogen peroxide of the present invention). There is.).

In the anthraquinone method, an working solution in which anthraquinones are dissolved in an organic solvent is used.

Examples of anthraquinones used include anthraquinone, tetrahydroanthraquinone, alkyl anthraquinone, and alkyltetrahydroanthraquinone. Hereinafter, anthraquinone and alkyl anthraquinone may be collectively referred to as (alkyl) anthraquinone. Further, tetrahydroanthraquinone and alkyl tetrahydroanthraquinone may be collectively referred to as (alkyl) tetrahydroanthraquinone. The (alkyl) anthraquinone and the (alkyl) tetrahydroanthraquinone may each be a mixture of multiple (alkyl) anthraquinones and (alkyl) tetrahydroanthraquinones. Examples of the (alkyl) anthraquinone include anthraquinone, ethyl anthraquinone, t-butyl anthraquinone, and amyl anthraquinone. Examples of the (alkyl) tetrahydroanthraquinone include tetrahydroanthraquinone, ethyl tetrahydroanthraquinone, t-butyl tetrahydroanthraquinone, and amyltetrahydroanthraquinone.

As the alkyl group contained in the anthraquinones, an alkyl group having 1 to 10 carbon atoms is preferable, and an ethyl group, a butyl group or an amyl group is particularly preferable.

As the organic solvent, either a non-polar solvent or a polar solvent can be used, but a mixed solvent of a non-polar solvent and a polar solvent is preferable. Examples of the non-polar solvent include aromatic hydrocarbons, specifically, benzene or a benzene derivative containing an alkyl substituent having 1 to 5 carbon atoms. Examples of the benzene derivative include pseudocumene. Examples of the polar solvent include higher alcohols such as diisobutylcarbinol, carboxylic acid esters, tetrasubstituted ureas, cyclic ureas, and trioctylphosphoric acid. A preferred organic solvent is a combination of an aromatic hydrocarbon and a higher alcohol, or a combination of an aromatic hydrocarbon and a cyclohexanol, a carboxylic acid ester of an alkylcyclohexanol or a tetrasubstituted urea.

When the non-polar organic solvent and the polar organic solvent are mixed, the mixing ratio (volume) is preferably non-polar organic solvent: polar organic solvent = 9: 1 to 1: 9, more preferably 8: 2 to 2: 8. 4: 6 to 6: 4 is particularly preferable.

With reference to FIG. 1, in the anthraquinone method, hydrogenation treatment is performed in which hydrogen is added to the working solution. As a result, the anthraquinones in the working solution are hydrogenated to produce the corresponding anthraquinones (hydrogenation step). Next, the obtained anthrahydroquinones are oxidized with air or a gas containing oxygen and returned to the anthraquinones. At this time, hydrogen peroxide is generated and dissolved in the working solution (oxidation step). Then, the generated hydrogen peroxide is extracted with water and separated from the working solution (extraction step). Hydrogen peroxide is then subjected to a purification step and a concentration step according to a conventional method to be commercialized. On the other hand, the working solution after the extraction step is subjected to a hydrogenation step, and thereafter, it is repeatedly used in an oxidation step, an extraction step, and so on.

After the extraction step and before the hydrogenation step, if necessary, a regeneration step of extracting a part of the working solution and regenerating it can be performed. The regeneration of the working solution can be carried out by removing by-products generated by the continuous production of hydrogen peroxide by known means such as distillation and chemical reaction, and returning the working solution after removing impurities to the hydrogen peroxide production step. ..

In the hydrogenation step, a catalyst is added to the working solution and subjected to a hydrogenation reaction. It is preferable to use the catalyst of the present invention as the hydrogenation reaction catalyst. The amount of the catalyst used can be appropriately determined depending on the size of the reaction system and the like, but the catalyst slurry concentration in the working solution may be 1 to 100 g / l, particularly 5 to 100 g / l. preferable.

In the regeneration step, a working solution may be prepared using the organic solvent, anthraquinone, and tetraanthraquinone recovered by distillation, and the working solution may be brought into contact with the catalyst. It may be brought into contact with the catalyst. It is preferable to use the catalyst of the present invention as the regeneration catalyst.

In the hydrogen peroxide obtained by the method for producing hydrogen peroxide of the present invention, the content of the boron component is reduced.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples.

Method for measuring the amount of boron removed In the examples and comparative examples described later, the amount of boron removed (unit: μg-B / g-catalyst) was measured as follows.
Boron in the filtrate was quantified using ICP-OES (Optima 2100 DV, manufactured by Perkin Elmer). The measurement conditions were as follows.
Measurement condition:
Measurement wavelength: 249.677nm (B)
Gas flow rate
Plasma: 15L / min
Auxiliary: 0.2L / min
Carrier: 0.7L / min
RF output: 1300W
Sample flow rate: 1.5 ml / min
Number of repetitions: 3 times Then, using the value of the amount of boron in the filtrate, the amount of boron elution was calculated based on the following formula.
Boron elution amount (μg-B / g-catalyst) = Boron concentration in filtrate (μg-B / L) x Cleaning liquid usage amount (L) / Catalyst amount (g)

Preparation Example 1: Preparation of carrier A saturated solution of magnesium chloride hexahydrate [manufactured by Wako Pure Chemical Industries, Ltd.] is impregnated with 200 g of γ-alumina [trade name: KHD-12, manufactured by Sumitomo Chemical Industries, Ltd.]. , Stirred at 30 ° C. An aqueous ammonia solution was added to prepare the pH to be 9 to 11, and magnesium hydroxide was added to γ-alumina to immobilize the magnesium oxide after firing so that the mass ratio of magnesium oxide was 10% by mass. The obtained solid was separated from the aqueous solution and calcined at 600 ° C. for 24 hours to obtain _{Al2O3 -} MgO (MgO = 10% by mass) as a carrier.

Preparation Example 2: Preparation of catalyst 50 g of the carrier Al _{2O 3} -MgO obtained in Preparation Example 1 is impregnated (mixed) with 50 ml of a 1.7 mass% palladium chloride hydrochloric acid aqueous solution, and stirred in a hot water bath at 80 ° C. As a result, palladium was supported on the carrier.
By decantation, Pd / Al _{2O 3} -MgO and an aqueous solution of palladium chloride in hydrochloric acid were separated.
50 ml of pure water was added to Pd / Al _{2O 3} -MgO, an aqueous sodium hydroxide solution was added, 5 ml of 37% formalin was added while maintaining the pH at 10-11, and palladium was reduced in a hot water bath at 60 ° C.
After removing the supernatant by decantation, the solid was washed with pure water to obtain 1% by mass Pd / Al _{2O 3} -MgO as a catalyst.

Comparative Example 1
2.5 g of the carrier Al _{2O 3} -MgO (MgO = 10% by mass) obtained in Preparation Example 1 in a polypropylene (PP) container washed with ultrapure water, and a 0.00035% by mass hydrochloric acid aqueous solution as a washing liquid. That is, 50 g of an aqueous hydrochloric acid solution having a pH of 4 was added, and the mixture was stirred with a magnetic stirrer at 26 ° C. for 1 hour. The obtained carrier-containing cleaning liquid was filtered through a 0.5 μm syringe filter to obtain a treated carrier and a filtrate.

Comparative Examples 2 to 6, Examples 1 to 5
A treated carrier and a filtrate were obtained in the same manner as in Comparative Example 1 except that the cleaning liquid and the treatment temperature were set as the conditions in Table 1.

Table 1 shows the amount of boron elution in Examples 1 to 5 and Comparative Examples 1 to 6. The relationship between pH and the amount of boron elution is shown in FIG.

Example 6
In a polypropylene (PP) container washed with ultrapure water, 2.5 g of the catalyst 1% by mass-Pd / _{Al2O 3 -} MgO (MgO = 10% by mass) obtained in Preparation Example 2 and 0.39 as a washing liquid. A mass% sodium hydroxide aqueous solution, that is, 50 g of a pH 13 sodium hydroxide aqueous solution was added, and the mixture was stirred with a magnetic stirrer at 26 ° C. for 1 hour. The obtained catalyst-containing cleaning liquid was filtered through a 0.5 μm syringe filter to obtain a treated catalyst and filtrate.

Examples 7 and 8, Comparative Example 7
The treated catalyst and filtrate were obtained in the same manner as in Example 6 except that the cleaning liquid and the treatment temperature were set as the conditions in Table 2.

Table 2 shows the amount of boron elution in Examples 6 to 8 and Comparative Example 7. The relationship between pH and the amount of boron elution is shown in FIG. The relationship between the washing temperature and the amount of boron elution is shown in FIG.

Claims (15)

It is a method for producing a catalyst for producing hydrogen peroxide by the anthraquinone method.
A production method for treating a carrier or a catalyst in which a transition metal is carried on the carrier with an alkaline aqueous solution having a pH of 12 or higher. The production method according to claim 1, wherein the concentration of the alkaline aqueous solution is 0.01 to 10% by mass. The production method according to claim 1 or 2, wherein the alkaline aqueous solution is a strong base aqueous solution. The production method according to claim 3, wherein the strong base aqueous solution is at least one selected from the group consisting of a sodium hydroxide aqueous solution, a potassium hydroxide aqueous solution and a sodium carbonate aqueous solution. The production method according to any one of claims 1 to 4, wherein the product is treated at 20 to 100 ° C. The production method according to any one of claims 1 to 5, wherein the catalyst for producing hydrogen peroxide is a hydrogenation reaction catalyst or a regeneration catalyst. The production method according to any one of claims 1 to 6, wherein the transition metal is at least one selected from the group consisting of palladium, rhodium, ruthenium, platinum and nickel. The carrier to be treated is at least one carrier selected from the group consisting of alumina, alumina magnesia, silica and silica-alumina, or a composite carrier of the carrier and an alkaline earth metal oxide. The manufacturing method according to any one of 7 to 7. The production method according to claim 8, wherein the alkaline earth metal oxide is at least one selected from the group consisting of MgO, CaO, BaO and SrO. The production method according to any one of claims 1 to 9, wherein the pH of the alkaline aqueous solution is 13 to 14. The production method according to any one of claims 1 to 10, wherein the carrier or catalyst is an unused carrier or catalyst. The production method according to any one of claims 1 to 11, wherein the treatment is performed at a temperature higher than 60 ° C and lower than 100 ° C. The production method according to any one of claims 1 to 12, wherein the concentration of the alkaline aqueous solution is 0.1% by mass or more and less than 0.5% by mass. A catalyst for producing hydrogen peroxide, wherein a transition metal is supported on a carrier and the boron content is 0.001% by mass or less. A method for producing hydrogen peroxide using the catalyst for producing hydrogen peroxide according to claim 14 in the anthraquinone method.

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