KR20240027936A - Method for manufacturing ammoxidation catalyst - Google Patents

Abstract

A method for producing a catalyst for ammonia oxidation according to an exemplary embodiment of the present application includes preparing a first solution containing a Mo precursor and a carrier; Bi precursor, Fe precursor, A precursor (A = at least one element selected from Ni, Mn, Co, Zn, Mg, Ca and Ba) and B precursor (B = selected from Li, Na, K, Rb and Cs) preparing a second solution comprising at least one element; mixing the first solution and the second solution to prepare a catalyst precursor slurry; and drying and calcining the catalyst precursor slurry, and additionally adding aqueous ammonia to the first solution, the second solution, or a mixture of the first solution and the second solution, and the catalyst before drying. The precursor slurry has a NH ₄ ⁺ /NO ₃ ^- molar ratio of 0.95 to 1.05.

Description

Method for producing a catalyst for ammoxidation {METHOD FOR MANUFACTURING AMMOXIDATION CATALYST}

This application relates to a method for producing a catalyst for ammonia oxidation.

The ammoxidation process of propylene is based on a reduction reaction that reacts ammonia with propylene and a mechanism of reoxidation by oxygen, and various compositions are used to increase the conversion rate of propylene, the reactant, and the selectivity and yield of acrylonitrile, the reaction product. catalysts have been studied.

Specifically, since the introduction of the Mo (molybdenum)-Bi (bismuth) oxide catalyst, catalysts to which metals with various oxidation states have been added have been studied to increase their catalytic activity and stability. As a result, depending on the type and amount of metal added, the yield of acrylonitrile is improved compared to the initial study.

However, despite the diversification of the catalyst composition, there was a lack of research on its structure and physical properties, so there was a limit to significantly increasing the conversion rate of propylene, a reactant during ammoxidation of propylene, and the selectivity of acrylonitrile, a reaction product. .

Therefore, in the technical field, research is needed on a catalyst for ammonia oxidation that can increase the conversion rate of propylene, a reactant, and the selectivity of acrylonitrile, a reaction product.

Republic of Korea Patent Publication No. 10-2006-0010817

This application seeks to provide a method for producing a catalyst for ammonia oxidation.

One implementation state of this application is,

Preparing a first solution containing a Mo precursor and a carrier;

Bi precursor, Fe precursor, A precursor (A = at least one element selected from Ni, Mn, Co, Zn, Mg, Ca and Ba) and B precursor (B = selected from Li, Na, K, Rb and Cs) preparing a second solution comprising at least one element;

mixing the first solution and the second solution to prepare a catalyst precursor slurry; and

Comprising the steps of drying and calcining the catalyst precursor slurry,

It includes the step of additionally adding ammonia water when preparing the first solution, the second solution, or a mixture of the first solution and the second solution,

The catalyst precursor slurry before drying provides a method for producing a catalyst for ammonia oxidation, wherein the NH ₄ ⁺ /NO ₃ ^- molar ratio is 0.95 to 1.05.

In addition, other embodiments of this application are:

A method for producing acrylonitrile is provided, which includes the step of subjecting propylene and ammonia to an ammonia oxidation reaction in the presence of an ammonia oxidation catalyst prepared according to the above production method.

The method for producing a catalyst for ammonia oxidation according to an exemplary embodiment of the present application is to adjust the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying to 0.95 to 1.05, thereby controlling the activity and stability of the catalyst for ammonia oxidation to be prepared. can be improved.

Therefore, when the catalyst for ammonia oxidation prepared according to an exemplary embodiment of the present application is applied to the manufacturing process of acrylonitrile, the conversion rate of propylene and the selectivity of acrylonitrile can be improved, and accordingly, high yield can be achieved. Acrylonitrile can be manufactured.

Figure 1 is a diagram showing an SEM image of a catalyst for ammonia oxidation according to Example 1 of the present application.

Hereinafter, this specification will be described in more detail.

In this specification, when a member is said to be located “on” another member, this includes not only the case where a member is in contact with another member, but also the case where another member exists between the two members.

In this specification, when a part “includes” a certain component, this means that it may further include other components rather than excluding other components unless specifically stated to the contrary.

As mentioned above, acrylonitrile is mainly produced by ammoxidation of propylene. Due to the nature of the oxidation reaction, the ammoxidation reaction proceeds as a complete oxidation reaction such as the production of CO and CO ₂ , and also the selectivity to acrylonitrile decreases due to various side reactions such as partial oxidation reaction of propylene. Therefore, the demand for catalysts showing higher activity and selectivity for commercial applications is increasing, and research on catalysts that can meet these requirements is necessary. Accordingly, the present application seeks to provide a method for producing a catalyst for ammonia oxidation that has high activity due to excellent propylene conversion rate and acrylonitrile selectivity.

A method for producing a catalyst for ammonia oxidation according to an exemplary embodiment of the present application includes preparing a first solution containing a Mo precursor and a carrier; Bi precursor, Fe precursor, A precursor (A = at least one element selected from Ni, Mn, Co, Zn, Mg, Ca and Ba) and B precursor (B = selected from Li, Na, K, Rb and Cs) preparing a second solution comprising at least one element; mixing the first solution and the second solution to prepare a catalyst precursor slurry; and drying and calcining the catalyst precursor slurry, and additionally adding aqueous ammonia when preparing the first solution, the second solution, or a mixture of the first solution and the second solution, and drying the catalyst precursor slurry. The previous catalyst precursor slurry has a NH ₄ ⁺ /NO ₃ ^- molar ratio of 0.95 to 1.05.

A method for producing a catalyst for ammonia oxidation according to an exemplary embodiment of the present application includes preparing a first solution containing a Mo precursor and a carrier; and Bi precursor, Fe precursor, A precursor (A = at least one element selected from Ni, Mn, Co, Zn, Mg, Ca and Ba) and B precursor (B = selected from Li, Na, K, Rb and Cs) and preparing a second solution containing at least one element.

The Mo precursor, Bi precursor, Fe precursor, A precursor (A = at least one element selected from Ni, Mn, Co, Zn, Mg, Ca and Ba), B precursor (B = Li, Na, K, Rb and At least one element selected from Cs) is a precursor of a metal constituting a catalyst for ammonia oxidation, and the metal molar ratio can be adjusted by adjusting the content of the precursor in the first solution and the second solution. In addition, there is no particular limitation as the precursor of the metal, and ammonium salts, nitrates, carbonates, chlorides, lactates, hydroxides, organic acid salts, oxides, or mixtures thereof of the metal elements may be used in combination.

The first solution and the second solution may each include a solvent such as water, HNO ₃ , etc.

In an exemplary embodiment of the present application, the carrier is SiO ₂ , Al ₂ O ₃ , MgO, MgCl ₂ , CaCl ₂ , ZrO ₂ , TiO ₂ , B ₂ O ₃ , CaO, ZnO, BaO, ThO ₂ , SiO ₂ -Al ₂ O ₃ , SiO ₂ -MgO, SiO ₂ -TiO ₂ , SiO ₂ -V ₂ O ₅ , SiO ₂ -CrO ₂ O ₃ , SiO ₂ -TiO ₂ -MgO and at least one selected from the group consisting of zeolite. silica (SiO ₂ ) is more preferred.

The carrier may include a plurality of pores, and in this case, the average diameter can be obtained by taking the arithmetic average of the diameters of the plurality of pores.

Based on the total weight of the ammonia oxidation catalyst, the content of the carrier may be 30% by weight to 70% by weight, and 40% by weight to 60% by weight. When the content range of the carrier as described above is satisfied, the ammonia oxidation catalyst can be stably supported and the activity of the ammonia oxidation catalyst may not be inhibited.

Meanwhile, at the beginning of the catalytic reaction, a process is required in which reactants are chemically adsorbed on the catalyst surface, and the active site and surface area of the catalyst are directly related to the adsorption capacity and the resulting chemical reaction. Additionally, chemical adsorption on the catalyst surface tends to increase as the temperature increases, although the adsorption rate is slower than physical adsorption. In this regard, the ammonia temperature desorption (NH ₃ -TPD) method, which measures the degree of acid site strength of the catalyst by the degree of desorption of ammonia (NH ₃ ) (TPD: Temperature Programmed Desorption), is widely known. In the present application, the ammonia (NH ₃ ) adsorption amount of the catalyst and carrier can be measured using the ammonia elevated temperature desorption method (NH ₃ -TPD).

A method for producing a catalyst for ammonia oxidation according to an exemplary embodiment of the present application includes the steps of mixing the first solution and the second solution to prepare a catalyst precursor slurry; and drying and calcining the catalyst precursor slurry.

In particular, in one embodiment of the present application, aqueous ammonia is additionally added to the first solution, the second solution, or a mixture of the first solution and the second solution, thereby reducing NH ₄ ⁺ /NO ₃ of the catalyst precursor slurry before drying. ^- The molar ratio is characterized as 0.95 to 1.05.

The NH ₄ ⁺ /NO ₃ ^- mole ratio of the catalyst precursor slurry before drying may be 0.95 to 1.05, 0.97 to 1.03, and 0.99 to 1.01.

As in an exemplary embodiment of the present application, when ammonia water is not additionally added to the first solution, the second solution, or the mixture of the first solution and the second solution, the catalyst precursor slurry before drying is formed by the metal precursor solution. The NH ₄ ⁺ /NO ₃ ^- molar ratio is about 0.85 or less. However, according to an exemplary embodiment of the present application, by additionally adding aqueous ammonia to the first solution, the second solution, or a mixture of the first solution and the second solution, NH ₄ ⁺ /NO of the catalyst precursor slurry before drying ₃ ^- The molar ratio can be adjusted from 0.95 to 1.05.

By adjusting the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying to 0.95 to 1.05, a similar amount of NH ₄ ⁺ as NO ₃ ^- can be formed, thereby increasing the degree of freedom of metal cations, Uniformity between reactions of the catalyst precursor slurry can be improved. Therefore, the activity and wear strength of the finally produced catalyst for ammonia oxidation can be increased.

If the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying is less than 0.95, the increase in activity and wear strength of the ammonia oxidation catalyst is small compared to the prior art, which is not desirable. In addition, if the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying exceeds 1.05, precipitation may occur rapidly due to an increase in pH, and thus the uniformity between reactions of the catalyst precursor slurry may decrease. It is not desirable because

In an exemplary embodiment of the present application, the aqueous ammonia can be added in the step of preparing the first solution, and can be added in the step of preparing the second solution, and the first solution and the second solution are mixed. It can be put in at time. It is more preferable to add the ammonia water to the first solution in the step of preparing the first solution, but it is not limited to this. In particular, when adding ammonia water in the step of preparing the second solution, or adding ammonia water when mixing the first solution and the second solution, local precipitation may occur. To prevent this, a metering pump, etc. It is desirable to add ammonia water in small amounts using .

The amount of ammonia water added can be appropriately adjusted so that the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying satisfies 0.95 to 1.05. If an excessive amount of ammonia water is added, rapid precipitation may occur, and the metals contained in the first solution, the second solution, or a mixture thereof may precipitate in an undispersed form, thereby reducing the activity and wear strength of the catalyst. may decrease.

In an exemplary embodiment of the present application, the step of preparing the catalyst precursor slurry may be performed at a temperature of 40°C to 70°C, and may be performed at a temperature of 40°C to 60°C. By carrying out the step of preparing the catalyst precursor slurry at a temperature of 40°C to 70°C, the reaction rate of the catalyst precursor slurry can be increased, and the activity and wear strength of the ammonia oxidation catalyst thus prepared can be improved. . In addition, when the step of preparing the catalyst precursor slurry is performed at a temperature of less than 40° C., the increase in activity and wear strength of the ammonia oxidation catalyst may be minimal compared to the prior art. In addition, when the step of preparing the catalyst precursor slurry is performed at a temperature exceeding 70° C., the uniformity of the ammonia oxidation catalyst produced may decrease due to a decrease in moisture and NH ₄ ⁺ .

In an exemplary embodiment of the present application, the catalyst for ammonia oxidation may be represented by the following formula (1).

[Formula 1]

Mo ₁₂ Bi _a Fe _b A _c B _d O _x

In Formula 1,

A is at least one element selected from Ni, Mn, Co, Zn, Mg, Ca and Ba,

B is at least one element selected from Li, Na, K, Rb and Cs,

a, b, c, d and x are the fractions of atoms or groups of atoms, respectively;

a is 0.1 to 7, b is 0.1 to 10, c is 0.1 to 8, d is 0.01 to 1, and x is a value determined according to the oxidation state of each element.

In an exemplary embodiment of the present application, it is more preferable that A in Formula 1 is Ni and B is K, but the present invention is not limited thereto.

In an exemplary embodiment of the present application, the steps of drying and calcining the catalyst precursor slurry may use methods known in the art.

For example, the step of drying the catalyst precursor slurry can be done by drying using an oven or spray drying. There is no particular limitation as long as the drying conditions are such that spherical particles of a size suitable for the fluidized bed reaction can be obtained from the metal precursor, and in the case of spray drying, it is carried out at an inlet temperature of 210°C to 255°C and an outlet temperature of 130°C to 150°C. You can. When the temperature conditions for spray drying are met, catalyst precursor particles and catalyst particles produced therefrom can be obtained in the form of spherical particles with a uniform and desirable particle size distribution. If the inlet temperature during spray drying is less than 210°C, undried fine particles may stick to the wall or bottom of the reactor, making it difficult to obtain catalyst particles of the desired size and shape after drying. In addition, if the inlet temperature during spray drying exceeds 255°C, the particles may not flow sufficiently and dry too quickly, forming catalyst particles in undesirable forms such as fine particles or hollow particles. Additionally, the outlet temperature during spray drying may be determined to be a certain level lower than the inlet temperature.

The calcination is a step of calcination of dry metal precursor particles, and there is no particular limitation as long as it is generally under the conditions of calcination of the metal precursor when producing a catalyst. For example, it may be performed at a temperature of 400°C to 700°C, or 500°C to 650°C for 1 hour to 6 hours, or 2 hours to 4 hours, but is not limited thereto. Conditions such as calcination temperature and calcination time can be appropriately selected to obtain the desired catalyst properties and reaction performance.

In addition, an exemplary embodiment of the present application provides a method for producing acrylonitrile, which includes the step of subjecting propylene and ammonia to an ammonia oxidation reaction in the presence of an ammonia oxidation catalyst prepared according to the above production method.

The method for producing the acrylonitrile may use a method known in the art, except that the ammonia oxidation catalyst prepared according to the exemplary embodiment of the present application is used. A more specific method for producing acrylonitrile is described in the Examples described later.

Hereinafter, in order to explain the present application in detail, examples will be given in detail. However, the embodiments according to the present application may be modified into various other forms, and the scope of the present application is not to be construed as being limited to the embodiments described in detail below. The embodiments of the present application are provided to more completely explain the present application to those with average knowledge in the art.

<Example>

<Example 1>

1) Preparation of catalyst precursor slurry

30 g of molybdenum precursor (ammonium paramolybdate, (NH ₄ ) ₆ Mo ₇ O ₂₄ ·4H ₂ O) was added to the reactor, and 90 g of hot water at about 100°C was added to form a solution. Next, 100.4 g of LUDOX AS-40, a colloidal silica suspension, was added to prepare a first solution. 29.9 g of 25% ammonia water was added to the first solution and stirred for about 30 minutes to prepare a first solution to which ammonia water was additionally added.

As a separate solution from the first solution, 31.2 g of nickel precursor (Ni(NO ₃ ) ₂ ·6H ₂ 0), 12.7 g of iron precursor (Fe(NO ₃ ) ₃ ·9H ₂ O), and bismuth precursor (Bi( 6.9 g of [NO ₃ ) ₃ ·5H ₂ O], 0.14 g of potassium precursor (KNO ₃ ), 28 g of water, and 4.4 g of nitric acid were mixed and stirred well to prepare a second solution.

The second solution was added dropwise to the first solution and stirred vigorously. After the addition of the second solution was completed, the solution was further stirred at room temperature for one hour to prepare a catalyst precursor slurry. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the prepared catalyst precursor slurry was 0.95. The NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry can be calculated using Equation 1 below.

[Equation 1]

NH ₄ ⁺ /NO ₃ ^- molar ratio of catalyst precursor slurry = (number of moles of NH ₄ ⁺ present in the first solution and aqueous ammonia) / (number of moles of NO ₃ ^- present in the second solution)

2) Preparation of catalyst for ammonia oxidation

The catalyst precursor slurry was spray-dried under the conditions of an inlet temperature of 230°C and an outlet temperature of 140°C to form catalyst precursor particles, and the catalyst precursor particles were sintered at 580°C for 3 hours in an air atmosphere to form a catalyst for ammonia oxidation. Manufactured.

An SEM image of the catalyst for ammonia oxidation according to Example 1 is shown in Figure 1 below. As shown in Figure 1 below, it can be confirmed that the catalyst for ammonia oxidation according to Example 1 was formed in the form of spherical particles.

<Example 2>

After preparing the first solution, the same procedure as Example 1 was performed, except that the amount of ammonia water added was adjusted to 32.6 g. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying in Example 2 was 1.

<Example 3>

After preparing the first solution, the same procedure as Example 1 was performed, except that the amount of ammonia water added was adjusted to 35.3 g. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying in Example 3 was 1.05.

<Example 4>

The catalyst precursor slurry was prepared in the same manner as Example 2, except that a temperature condition of 40° C. was applied instead of a room temperature condition. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying in Example 4 was 1.

<Example 5>

The catalyst precursor slurry was prepared in the same manner as Example 2, except that a temperature condition of 50° C. was applied instead of a room temperature condition. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying in Example 5 was 1.

<Example 6>

The catalyst precursor slurry was prepared in the same manner as in Example 2, except that a temperature condition of 60° C. was applied instead of a room temperature condition. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying in Example 5 was 1.

<Comparative Example 1>

The same procedure as in Example 1 was performed, except that the process of adding ammonia water was excluded when preparing the first solution. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying of Comparative Example 1 was 0.85 or less.

<Comparative Example 2>

After preparing the first solution, the same procedure as Example 1 was performed, except that the amount of ammonia water added was adjusted to 27.2 g. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying of Comparative Example 2 was 0.9.

<Comparative Example 3>

After preparing the first solution, the same procedure as Example 1 was performed, except that the amount of ammonia water added was adjusted to 38.1 g. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying of Comparative Example 3 was 1.1.

<Comparative Example 4>

After preparing the first solution, the same procedure as Example 1 was performed, except that the amount of ammonia water added was adjusted to 40.8 g. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying of Comparative Example 4 was 1.15.

<Comparative Example 5>

The catalyst precursor slurry was prepared in the same manner as Comparative Example 1, except that a temperature condition of 40° C. was applied instead of a room temperature condition. At this time, the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying of Comparative Example 5 was 0.85 or less.

<Experimental Example 1> Composition of catalyst for ammonia oxidation

The catalysts for ammonia oxidation prepared in each of the above examples and comparative examples were analyzed by ICP (Inductively Coupled Plasma). In this ICP analysis, an ICP-OES (Optima 8300DV, perkinelmer) analysis device was used. In addition, in this ICP analysis, the specific sample preparation method and analysis conditions were as follows.

First, samples for analysis were prepared by the following method.

0.2 g of catalyst sample was placed in a cornial tube and its weight was accurately measured. 1 mL of hydrochloric acid and 0.04 mL of hydrofluoric acid were added to this sample and quickly sealed. It was dissolved in a sonicator for 1 hour, and when the sample was completely dissolved, 1 mL of saturated boric acid water and an internal standard were added and diluted with 20 mL of ultrapure water. After neutralizing residual hydrofluoric acid at low temperature, samples were prepared by shaking and filtering, and ICP analysis was performed on these analysis samples using the following method.

First, ICP-OES analysis equipment was prepared by the following method.

1. Check the condition for equipment operation.

2. Gas check: Ar gas, N ₂ purge gas, Shear gas

3. Check the power supply and operate the equipment cooler.

4. After checking equipment communication, proceed to warm up the equipment.

Next, the composition and content of metals (Mo, Bi, Fe, Ni, K, Si) contained in each catalyst and carrier were analyzed under the following analysis conditions.

* Analysis conditions:

RF power(W): 1300

Torch Height(mm): 15.0

Plasma Gas Flow (L/min): 15.00

Sample Gas Flow(L/min): 0.8

Aux. Gas flow (L/min): 0.20

Pump Speed(mL/min): 1.5

Internal Standard: Y or Sc

By this ICP analysis, the compositions of the ammonia oxidation catalysts prepared in Examples and Comparative Examples were Mo ₁₂ Bi ₁ Fe _2.2 Ni _7.5 K _0.1 O _x / 50 wt% SiO ₂ (x is the oxidation state of each element) It is a number determined accordingly).

<Experimental Example 2> Ammoxidation reaction of propylene

50 g of the catalyst prepared in the above examples and comparative examples was added to a fluidized bed reactor with an inner diameter of 3 cm and a height of 1 m (bench-scale). The reaction conditions were adjusted by adjusting the flow rate of the molar ratio of the reactants (C ₃ H ₆ : NH ₃ : Air = 1 : 1~1.3 : 1.9~2.3), and the reaction was carried out at 400°C to 460°C.

The reaction products were analyzed using a gas chromatograph (Agilent GC 7890) equipped with a PolaPLOT-Q, Molseive 5A, and chromosorb 101 column, and the propylene conversion, acrylonitrile selectivity, and acrylonitrile yield were calculated as shown in Table 1 below. shown in

Additionally, the wear strength of the catalyst was measured as wear loss using the ASTM-D5757 method. More specifically, after filling a vertical inner tube with an inner diameter of 35 mm and a height of 710 mm with 50 g of catalyst, N ₂ gas was flowed at 10 L/min, and then the amount of catalyst collected in the collector was measured after 5 hours, using the following equation: Wear loss was measured using Equation 5.

[Equation 2]

Propylene conversion rate (%) = (moles of reacted propylene) / (moles of propylene supplied) × 100

[Equation 3]

Acrylonitrile (AN) selectivity (%) = (number of moles of acrylonitrile produced) / (number of moles of reacted propylene) × 100

[Equation 4]

Acrylonitrile (AN) yield (%) = (moles of acrylonitrile produced) / (moles of propylene supplied) × 100

[Equation 5]

Wear loss (%) = (Powder weight collected in collector for 5 hours) / (Initial catalyst weight) × 100

[Table 1]

As shown in Table 1, when the catalysts of Examples 1 to 6 are applied to the ammoxidation reaction of propylene, acrylonitrile selectivity, acrylonitrile yield, and wear loss are all superior compared to Comparative Examples 1 to 5. can confirm. In addition, considering the wear loss evaluation results of Examples 1 to 3 and Examples 4 to 6, it can be confirmed that it is more preferable that the step of preparing the catalyst precursor slurry is performed at a temperature of 40 ° C. to 60 ° C. .

Therefore, the method for producing a catalyst for ammonia oxidation according to an exemplary embodiment of the present application is to adjust the NH ₄ ⁺ /NO ₃ ^- molar ratio of the catalyst precursor slurry before drying to 0.95 to 1.05, thereby reducing the activity of the catalyst for ammonia oxidation to be prepared. and stability can be improved.

In addition, when the catalyst for ammonia oxidation prepared according to an exemplary embodiment of the present application is applied to the manufacturing process of acrylonitrile, the conversion rate of propylene and the selectivity of acrylonitrile can be improved, and accordingly, high yield can be achieved. Acrylonitrile can be manufactured.

Claims (8)

Preparing a first solution containing a Mo precursor and a carrier;
Bi precursor, Fe precursor, A precursor (A = at least one element selected from Ni, Mn, Co, Zn, Mg, Ca and Ba) and B precursor (B = selected from Li, Na, K, Rb and Cs) preparing a second solution comprising at least one element;
mixing the first solution and the second solution to prepare a catalyst precursor slurry; and
Comprising the steps of drying and calcining the catalyst precursor slurry,
It includes the step of additionally adding ammonia water when preparing the first solution, the second solution, or a mixture of the first solution and the second solution,
The method of producing a catalyst for ammonia oxidation, wherein the catalyst precursor slurry before drying has a NH ₄ ⁺ /NO ₃ ^- molar ratio of 0.95 to 1.05. The method for producing a catalyst for ammonia oxidation according to claim 1, wherein the carrier is silica. The method for producing a catalyst for ammonia oxidation according to claim 1, wherein the aqueous ammonia is added to the first solution in the step of preparing the first solution. The method of claim 1, wherein the step of preparing the catalyst precursor slurry is performed at a temperature of 40°C to 70°C. The method for producing a catalyst for ammonia oxidation according to claim 1, wherein the catalyst for ammonia oxidation is represented by the following formula (1):
[Formula 1]
Mo ₁₂ Bi _a Fe _b A _c B _d O _x
In Formula 1,
A is at least one element selected from Ni, Mn, Co, Zn, Mg, Ca and Ba,
B is at least one element selected from Li, Na, K, Rb and Cs,
a, b, c, d and x are the fractions of atoms or groups of atoms, respectively;
a is 0.1 to 7, b is 0.1 to 10, c is 0.1 to 8, d is 0.01 to 1, and x is a value determined according to the oxidation state of each element. The method for producing a catalyst for ammonia oxidation according to claim 5, wherein in Formula 1, A is Ni and B is K. The method for producing a catalyst for ammonia oxidation according to claim 1, wherein the step of drying the catalyst precursor slurry involves drying using an oven or spray drying. A method for producing acrylonitrile comprising the step of subjecting propylene and ammonia to ammoxidation in the presence of an ammoxidation catalyst prepared according to any one of claims 1 to 7.