KR101268832B1 - Method for reprocessing spent catalyst for alkylation of phenol - Google Patents

Abstract

In the spent catalyst used in the phenol alkylation reaction containing indium, an expensive rare metal of the present invention, from the spent catalyst, without recovering each of the catalyst components, it is possible to express the activity equivalent to the fresh catalyst directly. Provided are methods for preparing the regeneration catalyst.
The present invention provides a method for producing a reproducing catalyst from a spent catalyst comprising a dissolving step of a spent catalyst, wherein the dissolving step uses a nitric acid to dissolve using an alkaline solution.

Description

Recycling of waste catalyst for phenol alkylation reaction {METHOD FOR REPROCESSING SPENT CATALYST FOR ALKYLATION OF PHENOL}

The present invention is an indium containing indium (In), iron (Fe), vanadium (V) as essential components, which are useful for preparing o-cresol and 2,6-dimethylphenol by the alkylation (methylation) reaction of phenol. The present invention relates to a recycling method of a spent catalyst for an iron-vanadium oxide-based phenol alkylation reaction, and more particularly, to a waste catalyst that is used in an alkylation reaction to lose activity, having the same or equivalent activity, selectivity, and durability as a fresh catalyst. Relates to a method of remanufacturing.

2,6-dimethylphenol (2,6-DMP) and o-cresol prepared by regioselective alkylation of phenols are monomers of polyphenylene oxide (PPO or PPE), an engineering plastic, or antioxidants, flame retardants, It is used to prepare a variety of useful compounds, such as pharmaceutical intermediates.

Magnesium oxide-based catalyst (US 4,554,266) is used as a fixed-bed reactant catalyst for ortho position-selective catalysts of phenol that are industrially used. However, the reaction conditions are severe and the regeneration process has to be repeated frequently due to rapid deactivation of the catalyst. There is.

As another catalyst process, a fluidized bed catalyst process capable of smoothly performing a catalyst regeneration process has been developed and utilized industrially (JP 93,286,880).

On the other hand, the present inventors have developed an indium-iron- vanadium oxide-based catalyst improved by a metal component including a component having a hydrogenation capacity as a catalyst for the alkylation reaction of phenol (Korean Patent Application 2009-0043985), the catalyst is mild Under the reaction conditions, it was confirmed that not only the activity and selectivity but also the long-term reaction safety were excellent, so that it could be used in various types of alkylation catalyst processes, and in particular, it could be industrially used as a catalyst for a fixed bed reaction.

However, the catalyst also in the continuous operation, the catalytic activity decreases with the elapsed time of the reaction, especially when the supply conditions of the reactants LHSV = 1.0hr ^-1 or more, maintaining the production yield of 2,6-dimethylphenol more than 90% When operating at 2,6-dimethylphenol rich production alkylation reaction process conditions, it was necessary to regenerate the catalyst after several months of continuous operation.

The main reason for the catalyst deactivation is that in the present reaction where the reactants and products are phenols or alkylphenols, polyphenols having excellent thermal stability are produced on the catalyst by the above substances, and the carbonization of the catalyst causes coking of the catalyst. The catalyst particles are gradually deactivated by sintering during the regeneration process of decarbonization under the flow of oxygen or air in the state of filling the reactor with the catalyst, which is reduced in activity or by coking, and the regeneration and operation process are repeated. The activity becomes inferior and it becomes a waste catalyst. However, in the present invention, the waste catalyst is not only a catalyst whose activity is significantly reduced so that the sustainability of the performance (catalyst lifetime) is not maintained even by the decarbonization regeneration process by oxygen or air as well. As a result, the catalytic activity is lowered compared to the fresh catalyst and includes some deactivated catalysts.

However, in this alkylation catalytic reaction process using a catalyst containing expensive indium, one of the rare metals, increasing the catalyst life and increasing the recycling rate of indium become an important variable in lowering the catalyst ratio of the final product.

In general, the use of the waste catalyst is limited to recovering only valuable metals from the waste catalyst. However, the high purity recovery of each constituent from a catalyst containing a multimetallic component, particularly a catalyst containing three or more polymetallic components, complicates the recovery process and increases the cost of recovery, thereby reducing economic efficiency.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a fresh catalyst directly without recovering each of the catalyst components from a spent catalyst used in a phenol alkylation reaction containing an indium, which is an expensive rare metal. It is to provide a method for preparing a reproducing catalyst from the spent catalyst, which allows to express the activity equivalent to the catalyst.

It is also an object of the present invention to recover from the spent catalyst used in the indium-iron-vanadium-based phenol alkylation reaction without directly recovering each of the catalyst constituents and expressing the same activity as the fresh catalyst directly. It is to provide a method for producing a reproducing catalyst.

In order to achieve the above object of the present invention, the present invention provides a method for preparing a reproducing catalyst from a waste catalyst comprising a dissolving step of a spent catalyst, wherein the regeneration catalyst is dissolved using nitric acid in the dissolving step without using an alkaline solution. It provides a manufacturing method.

The present invention also provides a method for preparing a reproducing catalyst from a spent catalyst comprising the following steps, wherein in the dissolving step (b) a dissolution step is performed using an acid without using an alkaline solution.

(a) oxidation and coke removal of the spent catalyst;

(b) milling and dissolving;

(c) particle preparation step; And

(d) forming and firing steps.

The present inventors have completed the present invention by confirming that the rehabilitation catalyst prepared from the spent catalysts having undergone the above-described steps exhibits equivalent performance in terms of activity, selectivity and durability with the new catalyst.

When the rehabilitation catalyst is prepared from the spent catalyst according to the preparation method of the present invention, the regeneration catalyst according to the present invention showed the same activity, selectivity and durability as the fresh catalyst in the alkylation reaction of phenol. This means that it is possible to repeat the regeneration of the spent catalyst, and it is possible to drastically lower the catalyst ratio of the final product value in the catalytic reaction including the expensive rare metal component indium, especially the indium-iron-vanadium-based phenol alkylation catalysis process. It can increase the economics of the process.

1 shows the XRD pattern of the fresh catalyst used in the examples.
2 shows the XRD pattern after the waste catalyst and reoxidation / decarbonization process of the catalyst used in the examples.
3 shows the XRD pattern of the catalyst remanufactured in the examples.

Hereinafter, the present invention will be described in detail.

Indium-containing catalyst in the present invention includes a multi-metal catalyst containing indium, the multi-metal catalyst used in the present invention may be an indium-iron- vanadium-based phenol alkylation catalyst, as an embodiment A catalyst having a composition represented by the following formula (1).

[Formula 1]

In _a Fe _b V ₁ O _x (A) M 2 (B)]

In Chemical Formula 1, catalyst components such as In, Fe, and V are present in an oxide state, and a and b represent atomic ratios of each of In and Fe components based on composition 1 of V, where a is 0.05 to 1.0. , b is 0.05 to 1.0, x is a number determined according to the value of a, b and the oxidation state of In, Fe, V components based on the composition 1 of the vanadium component, M2 is silicate, aluminate or At least one component selected from the aluminum silicate compounds, A represents the weight ratio of the catalyst parent component, B represents the weight ratio of M2, A has a value in the range of 70-100 and B has a value in the range of 0-30. Have

In addition, another embodiment of the indium iron- vanadium-based phenol alkylation catalyst used in the present invention is a catalyst having a composition represented by the following formula (2).

[Formula 2]

In _a Fe _b V ₁ M1 _c O _x (A) M2 (B)]

In Chemical Formula 2, catalyst components such as In, Fe, V, and M1 are present in an oxide state, and M1 is cobalt (Co), nickel (Ni), manganese (Mn), molybdenum (Mo), and zinc (Zn). , At least one component selected from the group consisting of bismuth (Bi) and chromium (Cr), wherein a, b, and c represent atomic ratios of each of In, Fe, and M1 components based on composition 1 of V, wherein a is 0.05 to 1.0, b is 0.05 to 1.0, c is greater than O and less than 0.5, x is determined according to the values of a, b, c and the oxidation states of In, Fe, V, and M1 components based on the composition 1 of the vanadium component. And M2 represents one or more components selected from silicate, aluminate or aluminum silicate compounds of alkaline earth metals, A represents the weight ratio of the catalytic parent component, B represents the weight ratio of M2, and A ranges from 70 to 100. Has a value and B has a value ranging from 0 to 30.

In addition, another embodiment of the indium iron- vanadium-based phenol alkylation catalyst used in the present invention is a catalyst having a composition represented by the following formula (3).

(3)

In _a Fe _b V ₁ M1 _c M2 _d O _x (A) M3 (B)]

In Chemical Formula 3, catalyst components such as In, Fe, V, M1, and M2 are present in an oxide state, and M1 is cobalt (Co), nickel (Ni), manganese (Mn), molybdenum (Mo), and zinc ( Zn), bismuth (Bi) and chromium (Cr) represent one or more components selected from the group, M2 represents one or more components selected from alkaline earth metals or alkali metals, such as magnesium, calcium, barium, sodium, potassium, M3 represents one or more components selected from silicate, aluminate or aluminum silicate compounds of alkaline earth metals, and a, b, c and d represent the atomic ratios of the respective components of In, Fe, M1 and M2 based on the composition 1 of V. Where a is 0.05 to 1.0, b is 0.05 to 1.0, c is 0 to 0.5, d is 0 to 0.2 or less, and x is the value of a, b, c, d based on composition 1 of the vanadium component. And a number determined according to oxidation states of In, Fe, V, M1, and M2 components. A represents the weight ratio of the catalyst parent component consisting of In _a Fe _b V ₁ M1 _c M2 _d O _x , B represents the weight ratio of the components of M3, A represents a value from 70 to 100, and B ranges from about 0 to 30 Has the value of.

In the reaction of phenol and methanol under the catalyst represented by Chemical Formulas 1 to 3, the alkylation reaction is performed under a reducing atmosphere containing steam and hydrogen, in particular, steam and hydrogen, and at this time, the operation time as described above. As the activity gradually decreases, it becomes a waste catalyst.

The present invention comprises the steps of oxidation and coke removal of the spent catalyst; Grinding and dissolving step; Particle manufacturing step; And it provides a method for producing a reproducing catalyst from the spent catalyst comprising a molding and firing step.

In rehabilitation of the spent catalyst according to the present invention, one step is the oxidation and coking removal of the spent catalyst. Since the catalyst is operated in a reducing atmosphere during the alkylation reaction, the catalyst components are in reduced form, and it is necessary to undergo a reoxidation step to remove the spent catalyst from the reactor. At this time, since the reoxidation proceeds under oxygen (or air) flow, the coke component may be removed together with the reoxidation in the reactor, or after the reoxidized waste catalyst is recovered from the reactor, a separate decarbonization process is performed. can do.

At this time, in order to simultaneously remove the coke existing as activated carbon, graphite or carbide carbon, the decarbonization process should be performed at 300 to 700 ° C., preferably at 400 to 600 ° C., for at least 5 hours under oxygen (or air) flow. do. Decarbonization is not complete at 300 ° C. or lower, and sintering is severe at 700 ° C. or higher, which takes a long time to dissolve the catalyst component, which is not preferable.

After that, the spent catalyst undergoes a decarbonization process in order to facilitate the dissolution of each component. The crushing is preferably powdered to a particle size of 20 mesh or less, preferably 50 mesh or less.

The powdered spent catalyst undergoes a step of dissolving each component. Anionic oxides such as vanadium oxide and molybdenum oxide are generally dissolved using an alkaline solution such as ammonia water, and metal oxides are generally dissolved using an acid. A series of processes, such as dissolution of ammonia water-filtration-drying or removal of excess ammonia-acid dissolution-separation of components, not only complicates the reuse of waste catalysts, but also some components. On the spent catalyst in the form of this metal vanadate compound, the dissolution of the vanadium component by the ammonia water is not completely achieved.

In an effort to simplify the method of rehabilitation of the spent catalyst, the inventors have found that it can be remanufactured into a high performance catalyst even by dissolving with an appropriate amount of acid.

The amount of acid used is preferably 1.5 to 10 equivalents, preferably 2 to 8 equivalents, based on the highest oxidation state of each constituent metal component except vanadium, and the acid used is catalyst particles. It is preferable to use nitric acid for smooth removal of unnecessary cations and anions after preparation. If the amount of acid used is less than the above-mentioned value, there is a problem in dissolution, and when used in excess, it is ineffective compared to the amount of use and only complicates the post-treatment process.

The dissolution process is dissolved at room temperature using concentrated nitric acid, followed by dissolution at least for 12 hours at 40-100 ° C., preferably 50-90 ° C., in a dissolution tank with a condenser. After that, it is preferable to remove the excess nitric acid for the next step of neutralization process, it can be carried out a concentration process at 80 ~ 100 ℃.

The next step is the particle production step, and the co-precipitation process is carried out while simultaneously adding the nitric acid solution and ammonia water dropwise. At this time, the pH is neutralized in the range 5.5 to 9, and the final pH is adjusted to 6.5 ~ 8. Then, hydrothermal aging for 4-10 hours at 60 ~ 90 ℃, and then reduced temperature and filtered. The cake can be washed with deionized water or methanol.

The washed cake may be dispersed in deionized water and then dried by spray drying, or may be dried by an oven drying process. The dried cake can then be molded into various forms. In one embodiment, the dried cake may be subjected to a crushing process for molding by compression. In addition, when molding by a tableting method, a molding aid may be used as necessary. Known binders may be used as molding aids, for example graphite, titanium dioxide or hydrated titanium dioxide, hydrated aluminum or other aluminum-containing binders, silicon compounds and mixtures of aluminum compounds, clay minerals, alkoxysilanes, amphoterics And the like. The molding aid is not limited as long as it can be used to mold the catalyst powder, but may be used based on the catalyst powder weight of 2 to 15% by weight, preferably 3 to 10% by weight. In particular, in the present invention, graphite can be preferably used as a molding aid, and the graphite is uniformly mixed using 2 to 15% by weight, preferably 3 to 10% by weight, and molded by a tableting method. The molding may be formed by various known methods such as spraying or compression in addition to the tableting method, and the shape of the molded body may be shaped into various shapes and sizes, such as a cylinder type or a hollow-cylinder, depending on the reactor size, reaction type, and reaction conditions. Can be. In addition, the molding catalyst may be fired at 300 to 600 ° C, preferably at 350 to 500 ° C for 4 to 10 hours.

Hereinafter, the present invention will be described in detail by way of examples. The following examples are illustrative of the present invention, but the present invention is not limited to the following examples.

[ Example ]

Fresh catalyst catalyst ): [ In _(0.13) Fe _(0.83) Co _(0.05) Cr _(0.05) V ₁ O _x ] (95) Alborex (5)

The hollow shaped catalyst having the composition (OD x ID x H = 8 mm x 3 mm x 3.8 mm) has a specific surface area (BET) of 46.8 m ² / g, and the XRD pattern is shown in FIG. 1.

The composition catalyst was operated in a bench scale tubular reactor having a size of 1 ″ × 120 cm. The reaction temperature was 335-355 ° C., the reaction pressure was normal to 2 atmospheres, and LHSV = 1.0 hr ⁻¹ (phenol: methanol: water = 1: 1). 5: 1 m / m / m), continuous operation was possible for more than 5 months, after which the carbonization under degassing under air flow reduced the activity and 2,6-DMP selectivity slightly compared to the new catalyst. However, it was confirmed that the performance was well maintained.

< Waste Catalyst  And propertyization / Decarbonization  Course>

After the reaction, the reactant was stopped and the catalyst was reoxidized and decarbonization was performed at 350 ° C. for 12 hours while controlling the flow of air and nitrogen. The catalyst was then heat treated at 600 ° C. for 12 hours under air flow in a tubular kiln in order to separate the catalyst from the reactor, promote waste catalysis, and perform the decarbonization process in depth. The XRD pattern of the catalyst thus treated was the same as that of FIG. 2, and the specific surface area was 5 m ² / g.

Grinding and Dissolution Process

The hollow molded waste catalyst, which had undergone the above decarbonization, was pulverized and classified to 70 mesh or less. 20.0 g of the sorted waste catalyst powder was placed in a round flask equipped with a stirrer and a condenser, and 150 g of concentrated nitric acid (60%) was carefully added thereto, followed by dissolution for 12 hours at room temperature and 12 hours at 80 ° C. 100 g of deionized water was additionally added depending on the viscosity of the slurry during the dissolution process. Thereafter, the condenser was removed, concentrated at 90-100 ° C. for 6 hours, and then cooled.

Particle Manufacturing, Forming, and Firing Process

The co-precipitation process was performed while feeding the slurry solution at a rate of 3 ml / min using a pump and simultaneously supplying ammonia water (15%) solution with a neutralizer. At this time, the feed rate of the ammonia was added dropwise so that the pH of the slurry solution is adjusted in the range of 5.5 ~ 9, the final pH of the slurry solution was 7.5. Thereafter, the coprecipitation solution was hydrothermally aged at 80 ° C. for 6 hours, and then filtered after temperature reduction. The filter cake was washed twice with 100 cc of deionized water and twice with 50 cc of methanol, followed by oven drying at 120 ° C. The dried sample was classified into a size of 20 ~ 40mesh after compression molding, and calcined for 5 hours under an air atmosphere at 450 ℃.

The XRD pattern of the remanufactured catalyst prepared by the above process is shown in FIG. 3, and the specific surface area was 45.0 m ² / g.

<Catalyst activity investigation>

The catalytic activity in the Micro reactor was compared as follows for each catalyst remanufactured from fresh catalyst and spent catalyst. 4.0 g of the calcined catalyst was charged to a 1/2 "tubular reactor and reduced with 5% H ₂ / N ₂ for 12 hours at 270 ° C. Thereafter, at a reaction temperature of 340 ° C., at atmospheric pressure, phenol: methanol: water = 1: 5 A continuous reaction was carried out while feeding a mixture of 1 m / m / m with H ₂ (600 ml / hr) at a rate of 6.4 ml / hr The reaction results are shown in Table 1 below.

catalyst
Response time
(hrs)
Phenolic conversion
(%)
Selectivity (%) 2,6-dimethylphenol o-cresol Fresh catalyst 100 99.99 97.31 0.17 720 99.93 97.59 0.40 Catalyst Remanufactured from Spent Catalyst 100 99.99 96.93 0.09 720 99.90 97.05 0.82

As can be seen in Table 1, the regenerated catalyst prepared according to the present invention showed almost the same or equivalent phenol conversion, 2,6-DMP selectivity as the new catalyst, and even after the reaction time had elapsed. The conversion and selectivity were maintained, it was confirmed that the durability is also excellent.

Claims (8)

A process for producing a reproducing catalyst from a spent catalyst for phenol alkylation reaction comprising dissolving the spent catalyst, wherein the spent catalyst is a multimetallic catalyst containing indium, and using nitric acid without using an alkaline solution in the dissolution step. The manufacturing method of the regeneration catalyst to make it melt | dissolve. The method for producing a reproducing catalyst according to claim 1, wherein said multimetallic catalyst is an indium-iron-vanadium catalyst. The method for producing a reproducing catalyst according to claim 2, wherein the nitric acid is 1.5 to 10 equivalents based on the highest oxidation state of each constituent metal component except vanadium among the catalyst multimetal components. The method of claim 2, wherein the indium iron-vanadium catalyst is a catalyst having a composition represented by any one of the following Chemical Formulas 1 to 3.
[Formula 1]
In _a Fe _b V ₁ O _x (A) M 2 (B)]
(In Formula 1, the catalyst components of In, Fe, and V are present in an oxide state, and a and b represent atomic ratios of each of In and Fe components based on the composition 1 of V, where a is 0.05 to 1.0. , b is 0.05 to 1.0, x is a number determined according to the value of a, b and the oxidation state of In, Fe, V components based on the composition 1 of the vanadium component, M2 is silicate, aluminate or At least one component selected from the aluminum silicate compounds, A represents the weight ratio of the catalyst parent component, B represents the weight ratio of M2, A has a value in the range of 70-100 and B has a value in the range of 0-30. Have.)

(2)
In _a Fe _b V ₁ M1 _c O _x (A) M2 (B)]
In Chemical Formula 2, the catalyst components of In, Fe, V, and M1 are present in an oxide state, and M1 is cobalt (Co), nickel (Ni), manganese (Mn), molybdenum (Mo), and zinc (Zn). , At least one component selected from the group consisting of bismuth (Bi) and chromium (Cr), wherein a, b, and c represent atomic ratios of each of In, Fe, and M1 components based on composition 1 of V, wherein a is 0.05 to 1.0, b is 0.05 to 1.0, c is in the range of 0 to 0.5 or less, x is the value of a, b, c and the oxidation state of In, Fe, V, M1 components based on the composition 1 of the vanadium component. Therefore, M2 represents one or more components selected from silicate, aluminate or aluminum silicate compounds of alkaline earth metals, A represents the weight ratio of the catalyst parent component, B represents the weight ratio of M2, and A represents 70 to It has a value in the range of 100 and B has a value in the range of 0 to 30.)

(3)
In _a Fe _b V ₁ M1 _c M2 _d O _x (A) M3 (B)]
(In Formula 3, In, Fe, V, M1, M2, the catalyst component is present in an oxide state, M1 is cobalt (Co), nickel (Ni), manganese (Mn), molybdenum (Mo), zinc ( Zn), bismuth (Bi) and chromium (Cr), at least one component selected from the group consisting of M2 represents at least one component selected from the group consisting of magnesium, calcium, barium, sodium, potassium, M3 is alkaline earth metal Represents one or more components selected from silicate, aluminate or aluminum silicate compounds, wherein a, b, c and d represent the atomic ratio of each of In, Fe, M1 and M2 based on composition 1 of V, Is 0.05-1.0, b is 0.05-1.0, c is 0-0.5, d is 0 second and 0.2 or less, x is the value of a, b, c, d, and In, Fe based on the composition 1 of a vanadium component. Is a number determined according to the oxidation state of components V, M1, and M2, where A represents the weight ratio of the catalyst mother component. , B represents the weight ratio of M3, A has a value of 70-100, B has a value in the range 0-30). A process for producing a reproducing catalyst from a spent catalyst for a phenol alkylation reaction comprising the following steps, wherein the spent catalyst is a multimetallic catalyst comprising indium, and (b) using nitric acid without using an alkaline solution in the dissolution step. Process for preparing regenerating catalyst to dissolve:
(a) oxidation and coke removal of the spent catalyst;
(b) milling and dissolving;
(c) particle preparation step; And
(d) forming and firing steps. 6. The process for producing a reproducing catalyst according to claim 5, wherein the multimetallic catalyst is an indium iron-vanadium catalyst. The method for producing a reproducing catalyst according to claim 5, wherein the step (c) of producing particles is coprecipitated using ammonia water as a precipitant. The method for preparing a reproducing catalyst according to claim 6, wherein the indium-iron-vanadium-based phenol alkylation catalyst is a catalyst having a composition represented by one of the following Chemical Formulas 1-3:
[Formula 1]
In _a Fe _b V ₁ O _x (A) M 2 (B)]
(In Formula 1, the catalyst components of In, Fe, and V are present in an oxide state, and a and b represent atomic ratios of each of In and Fe components based on the composition 1 of V, where a is 0.05 to 1.0. , b is 0.05 to 1.0, x is a number determined according to the value of a, b and the oxidation state of In, Fe, V components based on the composition 1 of the vanadium component, M2 is silicate, aluminate or At least one component selected from the aluminum silicate compounds, A represents the weight ratio of the catalyst parent component, B represents the weight ratio of M2, A has a value in the range of 70-100 and B has a value in the range of 0-30. Have.)

(2)
In _a Fe _b V ₁ M1 _c O _x (A) M2 (B)]
In Chemical Formula 2, the catalyst components of In, Fe, V, and M1 are present in an oxide state, and M1 is cobalt (Co), nickel (Ni), manganese (Mn), molybdenum (Mo), and zinc (Zn). , At least one component selected from the group consisting of bismuth (Bi) and chromium (Cr), wherein a, b, and c represent atomic ratios of each of In, Fe, and M1 components based on composition 1 of V, wherein a is 0.05 to 1.0, b is 0.05 to 1.0, c is in the range of 0 to 0.5 or less, x is the value of a, b, c and the oxidation state of In, Fe, V, M1 components based on the composition 1 of the vanadium component. Therefore, M2 represents one or more components selected from silicate, aluminate or aluminum silicate compounds of alkaline earth metals, A represents the weight ratio of the catalyst parent component, B represents the weight ratio of M2, and A represents 70 to It has a value in the range of 100 and B has a value in the range of 0 to 30.)

(3)
In _a Fe _b V ₁ M1 _c M2 _d O _x (A) M3 (B)]
(In Formula 3, In, Fe, V, M1, M2, the catalyst component is present in an oxide state, M1 is cobalt (Co), nickel (Ni), manganese (Mn), molybdenum (Mo), zinc ( Zn), bismuth (Bi) and chromium (Cr), at least one component selected from the group consisting of M2 represents at least one component selected from the group consisting of magnesium, calcium, barium, sodium, potassium, M3 is alkaline earth metal Represents one or more components selected from silicate, aluminate or aluminum silicate compounds, wherein a, b, c and d represent the atomic ratio of each of In, Fe, M1 and M2 based on composition 1 of V, Is 0.05-1.0, b is 0.05-1.0, c is 0-0.5, d is 0 second and 0.2 or less, x is the value of a, b, c, d, and In, Fe based on the composition 1 of a vanadium component. Is a number determined according to the oxidation state of components V, M1, and M2, where A represents the weight ratio of the catalyst mother component. , B represents the weight ratio of M3, A has a value of 70-100, B has a value in the range 0-30).

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