Ammonia oxidation catalyst, preparation method thereof, and method for producing nitrile compounds

Abstract

The present invention discloses an ammonia oxidation catalyst, a preparation method thereof, and a method for producing nitrile compounds. The catalyst of the present invention has an XRD diffraction peak at 2θ = 27 ± 0.3° as X, and an XRD diffraction peak at 2θ = 28 ± 0.3° as Y, with the intensity ratio of X to Y satisfying 0 ≤ X / Y ≤ 1.1. The catalyst is prepared from raw materials including a support and an active component, wherein the support includes silicon dioxide and a support additive, wherein the support additive is an inorganic base. The catalyst of the present invention is used to produce nitrile compounds, achieving high raw material conversion and high selectivity for nitrile compound products.

Description

Technical Field

[0001] The present invention relates to the field of catalysts, in particular to a low-carbon olefin ammoxidation catalyst and a preparation method thereof, and a method for producing nitrile compounds. Background Art

[0002] Currently, the industrial production of propylene to unsaturated nitriles via ammoxidation generally adopts the Sohio fluidized bed process. The catalyst is the core of this technology. From the perspective of the main elements of the catalyst, it can be mainly classified into Mo-Bi and Sb-Fe series, among which Mo-Bi series catalysts occupy a major position. In recent years, the research and performance improvement of catalysts have also been mainly carried out around them, and a rich theoretical foundation has been formed, such as oxidation-reduction cycle, active site isolation, lattice defects and interphase synergy.

[0003] US 8455388 reported a Mo containing Ce element 12 Bi a Fe b A c D d E e F f G g Ce h Ox compounds, wherein A is at least one of sodium, potassium, rubidium, and cesium; D is at least one of nickel, cobalt, magnesium, zinc, manganese, calcium, strontium, cadmium, and barium; E is at least one of chromium, tungsten, boron, aluminum, gallium, indium, phosphorus, arsenic, antimony, vanadium, and tellurium; F is at least one of titanium, zirconium, hafnium, niobium, tantalum, thallium, and germanium; and G is at least one of silver, gold, ruthenium, rhodium, palladium, osmium, iridium, platinum, and mercury. The ratio of each atom is limited to 0.05 ≤ a ≤ 7, 0.1 ≤ b ≤ 7, 0.01 ≤ c ≤ 5, 0.1 ≤ d ≤ 12, 0 ≤ e ≤ 5, 0 ≤ f ≤ 5, 0 ≤ g ≤ 0.2, and 0.01 ≤ h ≤ 5, where 0.15 ≤ (a + h) / d ≤ 1, and 0.8 ≤ h / b ≤ 5. The diffraction peak intensity at 2θ=28±0.3° in the XRD pattern is selected as X, and the diffraction peak intensity at 2θ=26.5±0.3° is selected as Y, and the X / Y ratio is equal to or greater than 0.7. When 0.2≤(a+h) / d≤0.6 and 1≤h / b≤3, the X / Y ratio is equal to or greater than 0.8, and when 0.3≤(a+h) / d≤0.5 and 1.5≤h / b≤2, the X / Y ratio is equal to or greater than 0.9.

[0004] CN 107921428A discloses a composition of Mo 12 Bi a Fe b X c Y d Z e O fCompounds wherein X is one or more elements selected from nickel, cobalt, magnesium, calcium, zinc, strontium, and barium; Y is one or more elements selected from cerium, chromium, lanthanum, neodymium, yttrium, praseodymium, samarium, aluminum, gallium, and indium; and Z is one or more elements selected from potassium, rubidium, and cesium. The ratio of each atom is 0.1 ≤ a ≤ 2.0, 0.1 ≤ b ≤ 3.0, 0.1 ≤ c ≤ 10.0, 0.1 ≤ d ≤ 3.0, and 0.01 ≤ e ≤ 2.0, and f is the number of oxygen atoms required to satisfy the atomic valence requirements of the other elements present. The patent also limits the pH values ​​of the Mo solution / slurry and the Bi and Fe solutions, as well as the pH value after mixing the two, to avoid precipitation and aggregation of the metal elements and ensure uniform dispersion of the elements on the support surface.

[0005] As can be seen, the composition and preparation process of propylene ammoxidation catalyst are cumbersome and complicated, and there are many process variables, which have brought many difficulties to the amplification and stable production of catalyst. In addition, in the propylene ammoxidation process, there are also problems such as poor reproducibility of catalyst performance, low propylene conversion and low acrylonitrile yield. Therefore, simplifying the catalyst preparation process and reducing process control variables will be conducive to the repeatability and industrial amplification of catalyst production. Simultaneously, it is generally believed in the prior art that the addition of carriers or carrier additives does not have a significant impact on catalyst formation and catalytic effect during the catalyst preparation process, and it is generally believed that carrier additives can be introduced in any step before the catalyst slurry is dried. Summary of the Invention

[0006] In view of the above problems existing in the prior art, the present invention provides a new ammonia oxidation catalyst and a preparation method thereof. The catalyst of the present invention is used to produce nitrile compounds, which has the advantages of high raw material conversion rate and high selectivity of product nitrile compounds.

[0007] A first aspect of the present invention provides an ammonia oxidation catalyst, wherein the catalyst XRD diffraction peak at 2θ=27±0.3° is X, the catalyst XRD diffraction peak at 2θ=28±0.3° is Y, and the intensity ratio of X to Y satisfies 0≤X / Y≤1.1; the raw materials for preparing the catalyst include a carrier and an active component, the carrier includes silicon dioxide and a carrier additive, and the carrier additive is an inorganic base.

[0008] According to some embodiments of the present invention, preferably, 0.4≤X / Y≤1.0.

[0009] According to some embodiments of the present invention, preferably, the carrier additive is selected from at least one of potassium hydroxide, calcium hydroxide, magnesium hydroxide, cobalt hydroxide, nickel hydroxide, zirconium hydroxide, and ammonium hydroxide, preferably ammonium hydroxide. In the present invention, the carrier additive can be added in solid form or in liquid form after being dissolved in a liquid. In a more preferred embodiment, the carrier additive is an aqueous ammonium hydroxide solution.

[0010] According to some embodiments of the present invention, preferably, the general formula of the active component is Mo 12.0 Bi b Fe c D d E e O x , wherein D is selected from at least one of Li, K, Rb and Cs; E is selected from at least one of Ca, Mn, Co, Ni, Mg, Cr, Zr, La and Ce; wherein the value range of b is 0.1 to 5.0; the value range of c is 0.1 to 5.0; the value range of d is 0.1 to 5.0; the value range of e is 0.1 to 5.0; and x is the total number of oxygen atoms required to satisfy the valence of each element in the catalyst.

[0011] According to some embodiments of the present invention, preferably, the weight of the carrier is 35 to 65 weight % of the weight of the catalyst.

[0012] According to some embodiments of the present invention, preferably, the weight of the carrier additive is 0.1 to 5 weight % of the weight of the carrier.

[0013] A second aspect of the present invention provides a method for preparing an ammonia oxidation catalyst, comprising: mixing a solution containing an active component precursor with a solution containing a carrier, drying and calcining, wherein the carrier comprises silica and a carrier additive, and the carrier additive is an inorganic base.

[0014] According to some embodiments of the present invention, preferably, the solution containing the active component precursor includes a solution containing a Mo precursor and a solution containing a Bi precursor, a Fe precursor, a D precursor, and an E precursor, wherein D is selected from at least one of Li, K, Rb, and Cs; and E is selected from at least one of Ca, Mn, Co, Ni, Mg, Cr, Zr, La, and Ce.

[0015] According to some embodiments of the present invention, preferably, a solution containing a Mo precursor is mixed with a solution containing a carrier, and then mixed with solutions containing a Bi precursor, a Fe precursor, a D precursor, and an E precursor.

[0016] According to some embodiments of the present invention, the method for preparing a solution containing a carrier preferably comprises: adding a carrier additive to a solution containing silicon dioxide. The silicon dioxide in the solution containing silicon dioxide may be solid or liquid, such as, but not limited to, silicon dioxide, silica sol, or the like.

[0017] According to some embodiments of the present invention, preferably, the adding rate is 0.2 to 5 g / min, more preferably the adding rate is 0.5 to 2 g / min.

[0018] According to some embodiments of the present invention, preferably, the calcination conditions include: a temperature of 500-680°C, preferably 550-650°C.

[0019] According to some embodiments of the present invention, preferably, the calcination conditions include: a time of 0.2 to 4 hours, preferably 0.5 to 2.5 hours.

[0020] According to some embodiments of the present invention, the active component precursor may be a soluble salt of the active component, for example, the soluble salt of Mo may be but is not limited to (NH4)6Mo7O 24 For another example, the soluble salt of Bi may be, but is not limited to, Bi(NO 3 ) 3 .

[0021] According to some embodiments of the present invention, preferably, the carrier additive is selected from at least one of potassium hydroxide, calcium hydroxide, magnesium hydroxide, cobalt hydroxide, nickel hydroxide, zirconium hydroxide, and ammonium hydroxide, preferably ammonium hydroxide. In the present invention, the carrier additive can be added in solid form or in liquid form after being dissolved in a liquid. In a more preferred embodiment, the carrier additive is an aqueous ammonium hydroxide solution.

[0022] According to some embodiments of the present invention, the amount of the active component precursor is such that the general formula of the active component in the prepared ammonia oxidation catalyst is Mo 12.0 Bi b Fe c D d E e O x , wherein D is selected from at least one of Li, K, Rb and Cs; E is selected from at least one of Ca, Mn, Co, Ni, Mg, Cr, Zr, La and Ce; wherein the value range of b is 0.1 to 5.0; the value range of c is 0.1 to 5.0; the value range of d is 0.1 to 5.0; the value range of e is 0.1 to 5.0; and x is the total number of oxygen atoms required to satisfy the valence of each element in the catalyst.

[0023] According to some embodiments of the present invention, preferably, the weight of the carrier is 35 to 65 weight % of the weight of the catalyst.

[0024] According to some embodiments of the present invention, preferably, the weight of the carrier additive is 0.1 to 5 weight % of the weight of the carrier.

[0025] According to a specific embodiment of the present invention, the preparation method may include but is not limited to:

[0026] (1) dissolving the Mo precursor to obtain solution I;

[0027] (2) dissolving a Bi precursor, an Fe precursor, a D precursor, and an E precursor (i.e., elements other than Mo) to obtain a solution II, wherein D is selected from at least one of Li, K, Rb, and Cs; and E is selected from at least one of Ca, Mn, Co, Ni, Mg, Cr, Zr, La, and Ce;

[0028] (3) mixing a required amount of the carrier silica sol and the carrier additive to obtain a mixed solution III;

[0029] (4) mixing solution I with solution III, and then adding solution II to obtain a precipitate slurry;

[0030] (5) The slurry is spray-dried and calcined at 500-680°C for 0.2-4 hours to obtain a catalyst.

[0031] A third aspect of the present invention provides an ammonia oxidation catalyst obtained according to the above-mentioned preparation method, wherein the catalyst XRD diffraction peak at 2θ = 27 ± 0.3° is X, the catalyst XRD diffraction peak at 2θ = 28 ± 0.3° is Y, and the intensity ratio of X to Y satisfies 0≤X / Y≤1.1, preferably, 0.4≤X / Y≤1.0.

[0032] According to some embodiments of the present invention, preferably, the general formula of the active component is Mo 12.0 Bi b Fe c D d E e O x , wherein D is selected from at least one of Li, K, Rb and Cs; E is selected from at least one of Ca, Mn, Co, Ni, Mg, Cr, Zr, La and Ce; wherein the value range of b is 0.1 to 5.0; the value range of c is 0.1 to 5.0; the value range of d is 0.1 to 5.0; the value range of e is 0.1 to 5.0; and x is the total number of oxygen atoms required to satisfy the valence of each element in the catalyst.

[0033] According to some embodiments of the present invention, preferably, the weight of the carrier is 35 to 65 weight % of the weight of the catalyst.

[0034] According to some embodiments of the present invention, preferably, the weight of the carrier additive is 0.1 to 5 weight % of the weight of the carrier.

[0035] A fourth aspect of the present invention provides a method for producing nitrile compounds, comprising: contacting a light olefin feedstock, ammonia and air to carry out an ammoxidation reaction in the presence of the above-mentioned ammoxidation catalyst or the ammoxidation catalyst obtained according to the above-mentioned preparation method.

[0036] According to some embodiments of the present invention, preferably, the light olefin raw material is propylene and / or isobutylene.

[0037] According to some embodiments of the present invention, preferably, the molar ratio of the light olefin feedstock, ammonia and air is 1:1.05-1.3:9.2-9.8.

[0038] According to some embodiments of the present invention, preferably, the reaction conditions include: a temperature of 420-440°C.

[0039] According to some embodiments of the present invention, preferably, the reaction conditions include: a reaction pressure of 0.06 to 0.14 MPa.

[0040] According to some embodiments of the present invention, preferably, the propylene loading (WWH) of the ammoxidation catalyst is 0.06 to 0.10 h -1 .

[0041] According to some embodiments of the present invention, the nitrile compound may be, but is not limited to, acrylonitrile, methacrylonitrile, and the like.

[0042] Beneficial effects of the present invention:

[0043] The present invention improves the propylene conversion rate and the selectivity of acrylonitrile by providing a catalyst with specific elements and proportions and adding a carrier additive during the catalyst preparation process.

[0044] As demonstrated in the subsequent examples of the present invention, the activity of the catalyst of the present invention was evaluated in a fluidized bed reactor with an inner diameter of 38 mm, wherein the catalyst loading was 400 g, the reaction temperature was 430°C, the air:propylene molar ratio was 9.7:1, the ammonia:propylene molar ratio was 1.25:1, the reaction pressure was 0.08 MPa, and the propylene load (WWH) was 0.085 h -1 Under the conditions of , the propylene conversion rate is greater than 98%, the acrylonitrile single-pass yield is more than 81%, and the acrylic acid single-pass yield is less than 1.6%, achieving good results. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is the XRD diffraction peak pattern of the ammonia oxidation catalyst prepared in Example 1 of the present invention;

[0046] Figure 2 is the XRD diffraction peak pattern of the ammonia oxidation catalyst prepared in Example 2 of the present invention;

[0047] Figure 3 The XRD diffraction peak pattern of the catalyst prepared in Comparative Example 1;

[0048] Figure 4This is the XRD diffraction peak pattern of the catalyst prepared in Comparative Example 2. DETAILED DESCRIPTION

[0049] In order to make the present invention easier to understand, the present invention will be described in detail below with reference to embodiments. These embodiments are only for illustration and do not limit the scope of application of the present invention.

[0050] The test method of the present invention and the equipment used in the test are as follows:

[0051] Unless otherwise specified, the raw materials used in the Examples and Comparative Examples are all publicly available in the prior art, and can be purchased directly or prepared according to the preparation methods disclosed in the prior art. The definitions of propylene conversion, acrylonitrile selectivity, and single-pass yield in the present invention are as follows:

[0052]

[0053]

[0054]

[0055]

[0056] The XRD characterization of the catalysts was carried out on a Bruker D8 Advance SS instrument with a Cu target at 40 kV and 300 mA.

[0057] Unless otherwise specified, percentages and concentrations in the Examples and Comparative Examples are percentages by weight.

[0058] [Example 1]

[0059] 846.0 g (NH4)6Mo7O 24 ·4H2O was dissolved in 890 g of water to obtain solution (I). 111.1 g of Bi(NO3)3·5H2O, 517.6 g of Ni(NO3)2·6H2O, 287.6 g of Fe(NO3)3·9H2O, 135.5 g of Mg(NO3)2·6H2O, 3.6 g of KOH, and 17.8 g of Ca(NO3)3·4H2O were dissolved in 150 g of water by heating to obtain solution (II). 102 g of a 10% aqueous ammonia solution was added to 1250 g of silica sol having a silicon content of 40% at a rate of 2.0 g / min to form a mixed solution (III), wherein the ammonia solution accounted for 2% by weight. Solutions (I) and (III) were mixed, and then solution (II) was added to obtain a precipitate slurry, which was stirred at 80°C. The prepared slurry was formed into microspheres and dried in a spray dryer, and finally calcined in a rotary calciner at 590°C for 2 hours to obtain a Mo- 12.0 Bi0.6 Fe 1.8 K 0.2 Ni 4.5 Mg 1.3 Ca 0.2 O x The catalyst comprises 36.0% by weight of the carrier.

[0060] The XRD diffraction peak pattern of the obtained catalyst is as follows: Figure 1 As shown, the intensity of the diffraction peak at 2θ=27.4° (X) is 2346, the intensity of the diffraction peak at 2θ=28.3° (Y) is 2335, and the obtained X / Y intensity ratio is 1.00.

[0061] [Example 2]

[0062] 971.0 g (NH4)6Mo7O 24 ·4H2O was dissolved in 910 g of water to obtain solution (I). 107.2 g of Bi(NO3)3·5H2O, 497.7 g of Ni(NO3)2·6H2O, 306.8 g of Fe(NO3)3·9H2O, 121.6 g of Mg(NO3)2·6H2O, 36.7 g of RbNO3, and 81.2 g of Nd(NO3)3·6H2O were dissolved in 185 g of water by heating to obtain solution (II). 131 g of a 5% by weight KOH solution was added to 1850 g of silica sol having a silicon content of 40% at a rate of 1.5 g / min to form a mixed solution (III), in which the weight percentage of KOH was 0.9%. Solutions (I) and (III) were mixed, and then solution (II) was added to obtain a precipitate slurry, which was stirred at 120°C. The prepared slurry was formed into microspheres and dried in a spray dryer, and finally calcined in a rotary calciner at 610°C for 2 hours to obtain a Mo- 12.0 Bi 0.5 Fe 1.7 K 0.3 Rb 0.5 Ni 3.7 Mg 1.0 Nd 0.4 O x The catalyst comprises 40.3% by weight of the carrier.

[0063] The XRD diffraction peak pattern of the obtained catalyst is as follows: Figure 2 As shown, the intensity of the diffraction peak at 2θ=27.4° (X) is 2643, the intensity of the diffraction peak at 2θ=28.3° (Y) is 2923, and the obtained X / Y intensity ratio is 0.90.

[0064] [Example 3]

[0065] 369.1 g (NH4)6Mo7O24 ·4H2O was dissolved in 310 g of water to obtain solution (I). 46.3 g of Bi(NO3)3·5H2O, 280.1 g of Ni(NO3)2·6H2O, 134.4 g of Fe(NO3)3·9H2O, 2.3 g of KOH, 40.0 g of Mg(NO3)2·6H2O, 15.1 g of Ce(NO3)3·6H2O, and 188.3 g of Nd(NO3)3·6H2O were dissolved in 215 g of water by heating to obtain solution (II). 1.3 g of Ca(OH)2 powder was added to 1250 g of silica sol having a silicon content of 40% at a rate of 1.0 g / min to form mixture (III), wherein the weight percentage of Ca(OH)2 was 0.26%. Solutions (I) and (III) were mixed, and then solution (II) was added to obtain a precipitate slurry, which was stirred at 130°C. The prepared slurry was formed into microspheres and dried in a spray dryer, and finally calcined in a rotary calciner at 600 ° C for 2 hours to obtain a Mo- 12.0 Bi 0.55 Fe 1.9 K 0.2 Ca 0.1 Ce 0.2 Ni 5.5 Mg 0.9 Nd 2.5 O x The catalyst comprises 49.6% by weight of the carrier.

[0066] In the XRD diffraction peak spectrum of the obtained catalyst, the intensity X of the diffraction peak at 2θ=27.3° and the intensity Y of the diffraction peak at 2θ=28.2° had an X / Y intensity ratio of 0.62.

[0067] [Example 4]

[0068] 823.0 g (NH4)6Mo7O 24·4H2O was dissolved in 670 g of water to obtain solution (I). 114.4 g of Bi(NO3)3·5H2O, 704.0 g of Ni(NO3)2·6H2O, 220.9 g of Fe(NO3)3·9H2O, 109 g of Mg(NO3)2·6H2O, 100.7 g of Ce(NO3)3·6H2O, and 11.4 g of RbNO3 were dissolved in 410 g of water by heating to obtain solution (II). 3.6 g of Co(OH)2 powder was added to 1985 g of silica sol having a silicon content of 40% at a rate of 1.5 g / min to form mixture (III), wherein the weight percentage of Co(OH)2 was 0.45%. Solutions (I) and (III) were mixed, and then solution (II) was added to obtain a precipitate slurry, which was stirred at 130°C. The prepared slurry was formed into microspheres and dried in a spray dryer, and finally calcined in a rotary calciner at 620°C for 2 hours to obtain a Mo- 12.0 Bi 0.61 Fe 1.4 Co 0.1 Ce 0.6 Ni 6.2 Mg 1. 1Rb 0.2 O x The catalyst comprises 44.1% by weight of the carrier.

[0069] In the XRD diffraction peak spectrum of the obtained catalyst, the intensity X of the diffraction peak at 2θ=27.3° and the intensity Y of the diffraction peak at 2θ=28.2° had an X / Y intensity ratio of 0.68.

[0070] [Example 5]

[0071] 878.9 g (NH4)6Mo7O 24 ·4H2O was dissolved in 720 g of water to obtain solution (I). 130.2 g of Bi(NO3)3·5H2O, 400.2 g of Ni(NO3)2·6H2O, 353.8 g of Fe(NO3)3·9H2O, 158.8 g of Mg(NO3)2·6H2O, 71.7 g of Ce(NO3)3·6H2O, and 18.3 g of RbNO3 were dissolved in 205 g of water by heating to obtain solution (II). 134 g of a 10% aqueous ammonia solution was added to 1455 g of silica sol having a silicon content of 40% at a rate of 1.0 g / min to form a mixed solution (III), in which the weight percentage of the aqueous ammonia solution was 2.2%. Solutions (I) and (III) were mixed, and then solution (II) was added to obtain a precipitate slurry, which was stirred at 80°C. The prepared slurry was formed into microspheres and dried in a spray dryer, and finally calcined in a rotary calciner at 590°C for 2 hours to obtain a Mo- 12.0 Bi0.65 Fe 2.1 Ni 3.3 Mg 1.5 Ce 0.4 Rb 0. 3O x The catalyst comprises 36.7% by weight of the carrier.

[0072] In the XRD diffraction peak spectrum of the obtained catalyst, the intensity X of the diffraction peak at 2θ=27.3° and the intensity Y of the diffraction peak at 2θ=28.2° had an X / Y intensity ratio of 0.81.

[0073] [Example 6]

[0074] The method of Example 1 was followed, except that 102 g of an aqueous ammonia solution having a weight concentration of 10% was added to 1250 g of a silica sol having a silicon content of 40% at a rate of 5.0 g / min to form a mixed solution (III).

[0075] In the XRD diffraction peak spectrum of the obtained catalyst, the intensity X of the diffraction peak at 2θ=27.3° and the intensity Y of the diffraction peak at 2θ=28.2° had an X / Y intensity ratio of 0.85.

[0076] [Example 7]

[0077] The method of Example 1 was followed, except that 102 g of an aqueous ammonia solution having a weight concentration of 10% was added to 1250 g of a silica sol having a silicon content of 40% at a rate of 0.5 g / min to form a mixed solution (III).

[0078] In the XRD diffraction peak spectrum of the obtained catalyst, the intensity X of the diffraction peak at 2θ=27.3° and the intensity Y of the diffraction peak at 2θ=28.2° had an X / Y intensity ratio of 0.89.

[0079] [Comparative Example 1]

[0080] The method of Example 1 was followed, except that no ammonia solution was added.

[0081] The XRD diffraction peak pattern of the obtained catalyst is as follows: Figure 3 As shown, the intensity of the diffraction peak at 2θ=27.3° (X) is 2359, the intensity of the diffraction peak at 2θ=28.2° (Y) is 1884, and the obtained X / Y intensity ratio is 1.25.

[0082] [Comparative Example 2]

[0083] The method of Example 1 was followed, except that the ammonia solution was added at a rate of 10 g / min. It was found that the silica sol solution immediately gelled.

[0084] The XRD diffraction peak pattern of the obtained catalyst is as follows: Figure 4 As shown, the intensity of the diffraction peak at 2θ=27.2° (X) is 3120, the intensity of the diffraction peak at 2θ=28.1° (Y) is 1563, and the obtained X / Y intensity ratio is 2.00.

[0085] [Comparative Example 3]

[0086] The method of Example 1 was followed, except that 412 g of 10% by weight ammonia solution was added to the silica sol. It was found that the silica sol solution immediately gelled, and the ammonia solution accounted for 7.6% by weight of the carrier.

[0087] In the XRD diffraction peak spectrum of the obtained catalyst, the intensity X of the diffraction peak at 2θ=27.3° and the intensity Y of the diffraction peak at 2θ=28.2° had an X / Y intensity ratio of 2.89.

[0088] [Comparative Example 4]

[0089] The method of Example 2 was followed, except that no KOH solution was added.

[0090] In the XRD diffraction peak spectrum of the obtained catalyst, the intensity X of the diffraction peak at 2θ=27.3° and the intensity Y of the diffraction peak at 2θ=28.2° had an X / Y intensity ratio of 1.29.

[0091] [Comparative Example 5]

[0092] The method of Example 2 was followed, except that a 5% KOH solution was added at a rate of 20 g / min. It was found that the silica sol solution immediately gelled.

[0093] In the XRD diffraction peak spectrum of the obtained catalyst, the intensity X of the diffraction peak at 2θ=27.3° and the intensity Y of the diffraction peak at 2θ=28.2° had an X / Y intensity ratio of 2.60.

[0094] Test Example

[0095] The catalysts prepared in Examples 1 to 7 and Comparative Examples 1 to 5 were used to carry out the ammoxidation of propylene to produce acrylonitrile under the following conditions. The results are shown in Table 1.

[0096] The reactor and process conditions are as follows:

[0097] φ38 mm fluidized bed reactor

[0098] Reaction temperature 430℃

[0099] Reaction pressure 0.08MPa

[0100] Catalyst loading 400g

[0101] Catalyst propylene loading (WWH) 0.085 hours -1

[0102] Raw material ratio (molar): propylene / ammonia / air = 1 / 1.25 / 9.7.

[0103]

[0104] As can be seen from Table 1, the production of nitrile compounds using the catalyst of the present invention has the advantages of high raw material conversion rate and high nitrile compound product selectivity.

[0105] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, under the technical enlightenment provided by the present invention, as common knowledge in the art, other equivalent variations and improvements can be made, which should also be considered as the scope of protection of the present invention.

Claims

1. An ammonia oxidation catalyst, the catalyst XRD diffraction peak is at 2 θ =27±0.3° is X, and the catalyst XRD diffraction peak is at 2 θ =28±0.3° is Y, and the intensity ratio of X to Y satisfies 0.4≤X / Y≤1.1; the raw materials for preparing the catalyst include a carrier and an active component, the carrier includes silicon dioxide and a carrier additive, and the carrier additive is an inorganic base; The general formula of the active component is Mo 12.0 Bi b Fe c D d E e O x , wherein D is selected from at least one of Li, K, Rb and Cs; E is selected from at least one of Ca, Mn, Co, Ni, Mg, Cr, Zr, La and Ce; wherein b is in the range of 0.1 to 5.0; c is in the range of 0.1 to 5.0; d is in the range of 0.1 to 5.0; e is in the range of 0.1 to 5.0; and x is the total number of oxygen atoms required to satisfy the valence of each element in the catalyst; The weight of the carrier additive is 0.1 to 5% by weight of the carrier.

2. The ammonia oxidation catalyst according to claim 1, characterized in that 0.4≤X / Y≤1.

0.

3. The ammonia oxidation catalyst according to claim 1, characterized in that The carrier additive is selected from at least one of potassium hydroxide, calcium hydroxide, magnesium hydroxide, cobalt hydroxide, nickel hydroxide, zirconium hydroxide and ammonium hydroxide.

4. The ammonia oxidation catalyst according to claim 3, characterized in that The carrier additive is ammonium hydroxide.

5. The ammonia oxidation catalyst according to any one of claims 1 to 4, characterized in that The weight of the carrier is 35 to 65% by weight of the catalyst.

6. A method for preparing the ammonia oxidation catalyst according to any one of claims 1 to 5, comprising: A solution containing an active component precursor is mixed with a solution containing a carrier, dried and calcined, wherein the carrier comprises silicon dioxide and a carrier additive, and the carrier additive is an inorganic base.

7. The preparation method according to claim 6, characterized in that The solution containing the active component precursor includes a solution containing a Mo precursor and a solution containing a Bi precursor, a Fe precursor, a D precursor, and an E precursor, wherein D is selected from at least one of Li, K, Rb, and Cs; and E is selected from at least one of Ca, Mn, Co, Ni, Mg, Cr, Zr, La, and Ce.

8. The preparation method according to claim 7, characterized in that The solution containing the Mo precursor is mixed with the solution containing the carrier, and then mixed with the solution containing the Bi precursor, the Fe precursor, the D precursor, and the E precursor; and / or, the method for preparing the solution containing the carrier comprises: adding a carrier additive to a solution containing silica; And / or, the calcination conditions include: a temperature of 500-680° C.; and a calcination time of 0.2-4 hours.

9. The preparation method according to claim 8, characterized in that The carrier additive is added to the silica-containing solution at a rate of 0.2 to 5 g / min; And / or, the calcination conditions include: a temperature of 550-650° C.; and a calcination time of 0.5-2.5 hours.

10. The preparation method according to claim 9, characterized in that The carrier additive is added to the silica-containing solution at a rate of 0.5 to 2 g / min.

11. The ammonia oxidation catalyst obtained by the preparation method according to any one of claims 6 to 10, wherein the catalyst XRD diffraction peak is at 2 θ =27±0.3° is X, and the catalyst XRD diffraction peak is at 2 θ =28±0.3º is Y, and the intensity ratio of X to Y satisfies 0.4≤X / Y≤1.

1.

12. The ammonia oxidation catalyst according to claim 11, characterized in that 0.4≤X / Y≤1.

0.

13. A method for producing a nitrile compound, comprising: In the presence of the ammoxidation catalyst according to any one of claims 1 to 5 and 11 to 12 or the ammoxidation catalyst obtained by the preparation method according to any one of claims 6 to 10, a light olefin feedstock, ammonia and air are contacted to carry out an ammoxidation reaction.

14. The method according to claim 13, characterized in that The light olefin raw material is propylene and / or isobutylene; and / or, the molar ratio of the light olefin feedstock, ammonia, and air is 1:1.05-1.3:9.2-9.8; And / or, the reaction conditions include: temperature of 420-440° C., pressure of 0.06-0.14 MPa; and / or, the propylene loading of the ammoxidation catalyst is 0.06 to 0.10 h -1 .

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