WO2004101499A1

WO2004101499A1 - Process for producing (meth)acrylonitrile

Info

Publication number: WO2004101499A1
Application number: PCT/JP1996/000097
Authority: WO
Inventors: Nobuji Kishimoto; Taizou Matsueda
Original assignee: Nobuji Kishimoto; Taizou Matsueda
Priority date: 1996-01-22
Filing date: 1996-01-22
Publication date: 2004-11-25

Abstract

An industrially advantageous process for producing (meth)acrylonitrile in high yields by means of ammoxidation comprising catalytically oxidizing at least one saturated hydrocarbon selected between propane and isobutane with a gaseous mixture containing molecular oxygen and ammonia, which process is characterized by using a catalyst comprising a composite oxide represented by the following general formula (I): MoαSbβWϜOx (wherein α, β and Ϝ represent respectively the number of Mo, Sb and W atoms, provided when α is 1, then β is 0.5 to 10 and Ϝ is 0.5 to 10; and x is a number that is determined according to the valencies of the elements present) and supported on a refractory inorganic carrier.

Description

Specification

Method for producing (meth) acrylonitrile

Technical field

The present invention relates to a method for producing (meth) acrylonitrile by an ammoxidation method in which at least one kind of saturated hydrocarbon selected from the group consisting of propane and isobutane is brought into gaseous phase contact with molecular oxygen and ammonia.

Background art

(Meth) acrylonitrile is produced in large quantities as an intermediate raw material for various industrial products, mainly synthetic fibers and synthetic resins. In general, an ammoxidation method in which a gas phase is contacted with molecular oxygen and ammonia is known.

On the other hand, as the price of olefins has risen in recent years, attention has been focused on the development of methods for manufacturing various derivatives that were conventionally manufactured using olefins as raw materials using less expensive paraffins as raw materials. . The catalyst system used for producing (meth) atalylonitrile from propane or isobutane by the so-called ammoxidation method includes Sb-U-based oxide catalyst (JP-B-47-14371) and Sb-Sn-based oxide catalyst. (Japanese Patent Publication No. 50-28940), V-Sb-based oxide catalysts (JP-A-47-33783, JP-A-11-268668, JP-A-2-95439 and JP-A-2-261544), B i-Mo-based oxide catalyst (JP-A-48-16887, JP-B-55-42071 and JP-A-3-157356), VP-based oxide catalyst (JP-B-58-5188), Bi-V System oxide touch Media (JP-A-63-295545) and more recently, V-SnSb-Cu-based oxide catalysts (JP-A-4-275266), Mo-V-Te-Nb-based oxide catalysts (JP-A-2-257), Ag-Bi-V-Mo-based oxide catalyst (JP-A-3-58961), Ga-Bi-Mo-based or Ta-Bi-Mo-based oxide Catalyst (JP-A-3-58962), M

O_Ta or Mo—Nb-based oxide catalysts (Japanese Patent Laid-Open No. 5-213849) have been proposed. Further, mixed catalyst systems of some of the above-mentioned catalyst systems and a catalyst having an ammoxidation ability of orefin have been proposed (JP-A-63-295546, JP-A-64-38051, JP-A-2-38051). No. 17159, JP-A-2-43949, JP-A-2-75347, JP-A2-1

No. 11444 and JP-A-2-258065).

However, of these methods, the method of adding a small amount of a halide as a promoter to the reaction system gives the target product nitriles in a relatively high yield. It is difficult to implement industrially because there is a problem of corrosion of the material and there are restrictions on the material on the device. In addition, the method in which no promoter is added has a low yield of nitriles, and does not reach a level that can be industrially implemented.

Disclosure of the invention

Accordingly, an object of the present invention is to provide a method capable of industrially and advantageously producing (meth) acrylonitrile in a high yield by eliminating such disadvantages in the conventional method.

The present inventors have followed an ammoxidation method in which at least one saturated hydrocarbon selected from the group consisting of propane and isobutane is catalytically oxidized with a mixed gas containing molecular oxygen and ammonia in the presence of a catalyst. ) As a result of intensive studies on the method for producing acrylonitrile, a catalyst consisting of a composite oxide containing an oxide containing three elements of molybdenum, antimony and tungsten as essential components is used as a catalyst supported on a refractory inorganic carrier. As a result, it has been found that a higher yield of (meth) acrylonitrile can be obtained than in the conventional method, and the present invention has been achieved.

Thus, according to the present invention, there is provided a method for producing (meth) acrylonitrile by catalytic oxidation of propane and Z or isobutane in the gas phase with molecular oxygen and ammonia in the presence of a catalyst, comprising: The following general formula (I):

Mo a S b ^ Wr Ox (I)

(Where a and a represent the number of atoms of Mo, Sb, and W, respectively, when α is 1, ^ is 0.5 to 10, y is 0.5 to 10, and X is This value is determined by the atomic valence of the element.)

Provided by using a catalyst comprising a composite oxide represented by the following formula (1) supported on a refractory inorganic carrier.

Among the composite oxides represented by the general formula (I), those having a composition in which α is 1; S is 1 to 5 and y is 1 to 5 have a high nitrile content. Give in yield.

Further, in the present invention, together with the component elements of the complex oxide represented by the general formula (I), at least one kind selected from the group consisting of Nb, Cr, Mn, Fe, Co, and Ni An element (hereinafter sometimes referred to as a Group A element) in a quantity such that the atomic ratio of the Group A element to Mo is greater than 0 and less than or equal to 0.5. It is preferable to use it supported on an inorganic carrier. These books additionally containing Group A elements The catalyst of the invention is effective in improving the activity or selectivity. As the group A element, Nb is particularly preferred in that it improves the yield of the target product. The atomic ratio of the group A element to Mo is particularly preferably in the range of 0.05 to 0.2.

Further, in the present invention, at least one element selected from V, Nb, Cr, Mn, Fe, Co and Ni together with the component elements of the composite oxide represented by the general formula (I) Is referred to as A 'group element.) Is an amount such that the atomic ratio of the A' group element to Mo is more than 0 and not more than 0.5 and the A 'group element is It is preferable to use a catalyst composed of the contained composite oxide in an amount such that the atomic ratio is more than 0 and not more than 0.05, supported on a refractory inorganic carrier. As the A 'group element, V or Nb is particularly preferred from the viewpoint of improving the yield of the desired product. It is particularly preferable that the atomic ratio of the A 'group element to Mo is in the range of 0.05 to 0.2. The presence of group A 'elements is effective in improving the activity or selectivity of the catalyst. The optimal content of group A 'elements depends on the composition of Mo and W. If the atomic ratio of group A' elements to the sum of Mo and W exceeds the above range, selectivity is adversely affected. However, if the amount is less than the above range, the effect is small.

As the refractory inorganic carrier, silica, alumina, titania, zirconium, silica-alumina, silica-titania, silica-zirconia, and the like are preferable. It is particularly preferable in that it can be obtained at a high rate.

The catalyst used in the present invention can be prepared by a known method commonly used in the art. For example, using ammonium paramolybdate in pure water While heating, add an aqueous solution of ammonium metatungsdenate, add antimony trioxide as powder, and if necessary, V, Nb, Cr, Mn, Fe, C An aqueous solution of a compound of at least one element selected from the group consisting of o and Ni is added, a carrier such as silica or alumina is added thereto, and the mixture is stirred for a certain period of time, concentrated by heating, and the obtained slurry is obtained. It is prepared by baking at 400 to 800 ° C. after drying. The calcination can be carried out in the air, but can also be carried out under a high oxygen concentration or a low oxygen / element concentration. In the final calcination step, it is preferable to perform the treatment in an atmosphere having a low oxygen concentration (oxygen concentration: 1% to 15%) in order to obtain high catalytic performance.

The raw materials used for preparing the catalyst used in the present invention are not particularly limited, and include nitrates, oxides, hydroxides, chlorides, carbonates, acetates, metal acids, and ammonium metal salts of the elements used. Can be used.

As a raw material for the carrier, there can be variously used oxides, hydroxide powders, gels, sols, and the like, depending on the form of use of the catalyst, in addition to alumina, silica, silica-alumina, etc. .

As a raw material gas for the ammoxidation reaction according to the present invention, besides propane and / or isobutane, molecular oxygen and ammonia, a diluent gas can be used if necessary. Air or pure oxygen is used as the molecular oxygen source. The molar ratio of molecular oxygen is preferably 0.2 to 5 times the amount of propane, and the molar ratio of ammonia is preferably 0.2 to 3 times the amount of propane. As the diluent gas, an inert gas such as nitrogen, helium, carbon dioxide and the like, and steam are preferably used.

The gas-phase catalytic ammoxidation reaction according to the present invention comprises: It can be suitably carried out by contacting the above catalyst at a space velocity of 5500 hr ¹ and a temperature range of 300 ° C. to 600 ° C. The above-mentioned gas-phase catalytic ammoxidation reaction is usually performed under normal pressure, but can also be performed under reduced pressure or under increased pressure. The reaction system is not particularly limited, and any of a fixed bed system, a moving bed system, and a fluidized bed system can be used. In addition, a single-flow system or a recycling system may be used. Effect of the Invention In the ammoxidation method of the present invention, at least one kind of saturated hydrocarbon selected from the group consisting of propane and isobutane is separated in the presence of the above-mentioned catalyst comprising molybdenum, antine and evening stainless steel as essential components. (Meth) acrylonitrile can be industrially advantageously produced at a high yield by catalytic oxidation using a mixed gas containing dendritic oxygen and ammonia. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described more specifically with reference to examples. The conversion, single-stream yield and selectivity, including by-products, are defined by the following formulas.

When the raw material is propane raw material: Number of moles of propane reacted

Conversion (mol x 100

Number of moles of supplied propane Number of moles of each compound generated Number of carbon atoms of each compound

Selectivity (mol%) = XX 100 Number of moles of propane reacted 3 Number of moles of each compound produced Number of carbon atoms of each compound Single stream yield (mol%) = XX 100 Number of moles of propane supplied 3 When the raw material is isobutane raw material:

Number of moles of reacted isobutane

Conversion (mol%): X 100

Number of moles of supplied isobutane Number of moles of each compound generated Number of carbon atoms of each compound

Selectivity (mol%): X X 100

Number of moles of reacted isobutane 4 Number of moles of each compound produced Number of carbon atoms of each compound Single stream yield (mol%) = X X 100

Number of moles of isobutane supplied 4 Example 1

1 liter Torubi one car, alumina sol A- 200 (manufactured by Nissan Chemical Industries, Ltd., A 1 ₂ 0 ₃ concentration:. 10. 5wt%) 93. 0 g, silica sol Snow Tetsu box N (manufactured by Nissan Chemical Industries, Ltd., S i ( ₂ concentration: 20.5 wt.%) 47.6 g and 150 ml of water were charged, heated to about 80 ° C, and stirring was continued. On the other hand, the 300 meters l beaker foremost, para molybdate Anmoniumu _{_{((N Η 4) 6 Μο}} 7 0 24 · 4H 2 0, produced by Wako Pure Chemical Industries, Ltd. special grade reagent) were charged 1. 77 g, and water 100 m l, heated stirred After dissolving Te, this Metata tungsten acid Anmoniumu _{_{(((NH 4) 6 H}} 2 W 12 0 48) aqueous-MW-2 (Nippon Inorganic Color & chemical Co., Ltd., W0 ₃ as 5 OWT.% content) 13.91 pressurized tut, further 8 13 ₂ 0 ₃ (manufactured by Wako pure Chemical Industries, Ltd., purity 99.9%) 4. those dispersed in water of 100 m 1 to 38 g a homogenizer addition, 2 hours liquid at about 80 ° C After gradually adding the suspension to the mixed slurry of the alumina sol and the silica sol, the mixture was stirred at 80 ° C for 2 hours. Thereafter, the heating temperature was increased to 90 ° C., stirring was continued, and the mixture was concentrated for about 4 hours while evaporating water. After drying the paste at 120 ° C for 14 hours, It was fired at 450 ° C. in the air for 3 hours, and then fired at 65 ° C. for 3 hours in an atmosphere with an oxygen concentration of 10% (the remainder being nitrogen). The composition of the obtained catalyst is 40 wt.% Mo! In _{_{S b 3 W 3 O x /}} 3 0w t.% A l 2 O 3- 3 0 wt.% S i 0 was 2 (description of the composition of the subsequent catalyst, the left side of Bruno composition of the composite oxide , And the right side of / represents the composition of the carrier).

5 ml of the catalyst arranged in a mesh of 9 to 20 mesh was filled in a usual flow-type reaction apparatus and reacted. The composition of the reaction gas is C ₃ H ₈ ZNH ₃ / Oa / He / H ₂₀ = 1/2/4 / 7.5 / ₃ (molar ratio), space velocity is 900 hr-reaction temperature is 58 It was 0 ° C. The obtained results are shown in Table 1.o

Example 2

Para molybdate Anmoniumu, except that the amount of metatungstate Anmoniumu water solution and S b ₂ 0 _3, were changed respectively 1. 1 3 g, 1 4. 8 6 g and 4. 6 7 g, Example 1 ^ MoxSbsWsO / SOwt.KAlaOa-SOwt. ^ Sio2 in the same manner as described above. In the reaction, the composition of the reaction gas was changed to C ₃ H ₈ / NH ₃ _ 0 ₂ / He = 1/2 / ^/ 4 ^/ 7.5 (molar ratio), and the space velocity was changed to 7.50 hr- ¹ Except having performed, it carried out similarly to Example 1. Table 1 shows the obtained results.

Example 3

Para molybdate Anmoniumu, the amount of metatungstate Anmoniumu water solution and S b ₂ 0 _3, respectively 3. 5 9 g, except for changing the 5. 7 9 g and 3. 6 4 g, as in Example 1 Prepare in the same manner to obtain 40 wt. S b jWjO x / SO wt. ^ A laOs- S Ow t. ^ S i 0 ₂ The resulting catalyst was obtained. The reaction was carried out in the same manner as in Example 1 except that the reaction temperature was 540 ° C. Table 1 shows the obtained results.

Example 4

After adding metatungstate ammonia Niumu aqueous solution of para-molybdate Anmoniumu, before the addition of the S b ₂ 0 ₃ dispersion, further meta vanadate Anmoniumu (NH ₄ V0 _3, produced by Wako Pure Chemical Industries, Ltd. special grade reagent) Preparation was performed in the same manner as in Example 1, except that 0.175 g was dissolved by heating with 30 ml of water.

_{. O wt% A 1 2 0} 3 - was obtained 30 wt% S i 0 ₂ composition catalyst.. The reaction was carried out in the same manner as in Example 1 except that the reaction temperature was 560 ° C. Table 1 shows the obtained results.

Example 5

Change paramolybdate acid Anmoniumu, the amount of metatungstate Anmoniumu water solution and metavanadate Anmoniumu and S b ₂ 0 _3, their respective 1. 38 g, 14. 45 g, to 0. 164 g and 4. 54 g except that the performs prepared as in example 4, 40w t. Mc ^ S b 4 W 4 V 0 .i 8 Ox / / 30wt.% a l 2 O 3 -30wt.% composition of the S i 0 ₂ The catalyst was obtained. The reaction was carried out except that the composition of the reaction gas was changed to C ₃ H ₈ ZNH ₃ e = 1 2/4 / 7.5 (molar ratio), the space velocity to 750 hr ¹ , and the reaction temperature to 560 ° C. Was performed in the same manner as in Example 1. Table 1 shows the obtained results.

Example 6

Instead oxalate niobium metavanadate Anmoniumu solution (CB MM Co., with Nb ₂ 0 ₅ in terms 20. 5 wt.% Containing) a 0. 972 g 10 Preparation was performed in the same manner as in Example 4 except that an aqueous solution dissolved in warm water of Om 1 was added.

To obtain a catalyst having the composition of _{3 Owt.MS i 02 - A 1 2} 0 3. The reaction was carried out in the same manner as in Example 1 except that the reaction temperature was 57. Table 1 shows the obtained results.

Example 7

Chromium nitrate instead of metavanadate Anmoniumu solution _{(C r (N 0 3)} 3 · 9H 2 0, Wako Pure Chemical Industries, Ltd., purity 99.9%) of an aqueous solution prepared by dissolving 0. 600 g of warm water 100 m 1 except for adding, as example 4 the preparation was conducted in the same _{way, 40 wt% Mo b 3 W} 3 C r 0 15 0 30 wt% a 1 2 0 3 -... of 30 wt% S i 0 _2. A catalyst having the composition was obtained. The reaction was performed in the same manner as in Example 1. Table 1 shows the obtained results.

Example 8

Instead nickel nitrate metavanadate Anmoniumu solution _{(N i (N 0 3)} 2 · 6H 2 0, produced by Wako Pure Chemical Industries, Ltd. special grade reagent), except that the addition of an aqueous solution prepared by dissolving 0. 436 g of warm water 100 m l, not to put the prepared as in example 4, 4 Ow t. ^ Mc ^ S b 3 W 3 N i 0. 15 OxZ3 Ow t.% a 1 2 0 3 -3 Owt.% S i 0 2 of the composition A catalyst was obtained. The reaction was carried out in the same manner as in Example 1 except that the reaction temperature was 570 ° C. Table 1 shows the obtained results. Example 9

Instead manganese nitrate metavanadate Anmoniumu solution _{_{(Mn (N 0 3) 2}} · 6H 2 0, produced by Wako Pure Chemical Industries, Ltd. special grade reagent) except for adding an aqueous solution of 0. 431 g was dissolved in warm water of 100 m l, performed example 4 not to put the prepared similar to, 4 Ow t Mo! S b 3 W 3 Mn 0. 15 Ox / 30 wt.% a 1 2 0 3 - to obtain a 3 Ow t% S i catalyst composition of O _2.. The reaction was carried out in the same manner as in Example 1 except that the reaction temperature was 570 ° C. Table 1 shows the obtained results. Example 10

Except for not using silica sol Snowtex N performs prepared in the same manner as in Example 1, 57 wt.% Mo n S b 3 W 3 0 x / 43 wt.% A 1 2 0 ₃ composition catalyst Got. The reaction was performed in the same manner as in Example 1. Table 1 shows the obtained results. '

Comparative Example 1

Meta without a tungstate Anmoniumu, except for changing the amount of Paramoributen acid § emissions Moniumu and S b ₂ 0 ₃ in the respective 3. 80 g and 9.40 performs prepared as in Example 1, A catalyst having a composition of 4 Owt.% MoxSb ₃ Ox / 30 wt.% Al ₂ O ₃ -30 wt.% Sio ₂ was obtained. The reaction was performed in the same manner as in Example 1. Table 2 shows the obtained results.

Comparative Example 2

Without the use of S b ₂ 0 _3, except that the amount of para-molybdate Anmoniumu and Metatanda stainless acid Anmoniumu aqueous-MW-2 was changed to each 2. 74 g及beauty 21. 55 g, as in Example 1 the preparation was conducted, to obtain a 40 wt. ^ Mo ^ sOx S Owt. ^ a l aOg-S Owt. ^ S i 0 2 set configuration of the catalyst. The reaction was carried out in the same manner as in Example 1 except that the reaction temperature was changed to 520 ° C. Table 2 shows the obtained results.

Comparative Example 3

Without the use of para-molybdate Anmoniumu, metatungstate en Moniumu aqueous-MW-2 and S b ₂ 0 ₃ usage, respectively 15. 64 g, 4. except for changing the 92 g, in the same manner as in Example 1 Preparation, 40wt. % Was obtained _{_{Sb 1 W 1 Ox / 30wt.}} % A l 2 O 3 -30wt.% S i 0 ₂ composition catalyst. The reaction was performed in the same manner as in Example 1. Table 2 shows the obtained results.

Comparative Example 4

Para molybdate Anmoniumu, the amount of metatungstate Anmoniumu water solution and S b ₂ 0 _3, respectively 0. 88 g, 5. except for changing the 99 g and 9. 42 g, prepared as in Example 1 was carried out, to obtain a _{_{40wt.% MoiSb 15 W 3 Ox}} / 30wt.% a l 2 O 3-30wt.% S i 0 2 set configuration of the catalyst. The reaction was performed in the same manner as in Example 1. Table 2 shows the obtained results.

Comparative Example 5

Para molybdate Anmoniumu, the amount of metatungstate Anmoniumu water solution and S b ₂ 0 _3, respectively 0. 57 g, except for changing the 22. 3 g and 1. 40 g, prepared as in Example 1 was carried out to obtain a _{40 wt.% moiS b 3 Wi} 5 Ox / 30wt.% a l 2 O 3 -30wt.% S i 0 2 set configuration of the catalyst. The reaction was performed in the same manner as in Example 1. Table showing the results obtained

2 o

Comparative Example 6

Preparation was carried out in the same manner as in Example 4 except that the amount of ammonium metavanadate used was changed to 0.702 g, to obtain 41 wt.% Mo 1 Sb ₃ W ₃ V. _{... 6 0 X / 29} 5wt% A 1 2 0 3 - was obtained 29. 5 wt% S i 0 ₂ composition catalyst.. The reaction was carried out in the same manner as in Example 1 except that the reaction temperature was 540 ° C. Table 2 shows the obtained results.

Example 11 The reaction was carried out using the same catalyst used in Example 4. The reaction gas composition of _{_{i- C 4 H 1 () ZNH}} 3 Z0 2 / H eZH 2 0 = 1Z2Z4Z7. 5/3 ( molar ratio), the space velocity 900 hr the reaction temperature was 520 ° C der. The results showed that the conversion of isobutane was 69.0%, the selectivity of methacrylonitrile was 46.8%, and the methacrylonitrile single-stream yield was 32.3%.

2)

77 people J heart — No fr t_ii Hapano, No

V 华 Single-stream yield (%) Field catalyst, composition Composition temperature

CO (%) AN ³⁵ C ₃ , 4) HCN ⁵ A AMWjT_r,

3 6)

1 4 Owt.% OiSb ₃ W ₃₀ _x A 580 70.1 50.2 11.9 8.5

2 40 t.% OjSbsWsOx B 580 67.8 43.9 3.7 8.4 on3.0 o

3 4 Owt.% MoiSbifiOx A -540 72.3 40.1 9.8 7.3 on

6V. N U DO. On

4 40wt.% MoiSb ₃ W ₃ Vo.i ₅ O _x A 560 73.0 56.1 10.2 9.3 41.0 48.4

5 4 Owt.% Mo ₁ Sb ₄ W4Vo. ₁₈ Ox B 560 82.2 50.9 5.1 8.8 41.8 46.0

6 40 t.% MojSbsWsNbo.isOx A 570 71.2 52.8 11.3 8.7 37.6 45.6

7 40wt.% OiSb ₃ W ₃ Cro. ₁₅ Ox A 580 73.5 48.4 12.0 9.6 35.6 44.4

8 4 Owt.% MoiSbsWs io.xsOx A 570 68.9 52.1 11.4 8.3 35.9 43.8

9 4 Owt.% MojSbsWs no.isOx A 570 71.8 49.8 11.7 8.9 35.8 44.2

10 57 t.% MoiSb ₃ W ₃₀ _x A 580 76.3 37.4 6.2 9.3 28.5 33.3

As 1) a carrier, in Example _{_{_{1~9 A1 2 0 3: Si0 2}}} = l: 1 (weight ratio), was used in Example 10, A1 ₂ 0 _3.

2) Gas composition A:

1/2/4 / 7.5 / 3 (molar ratio)

Gas composition _{_{B:. C 3 H 8 /}} NH 3/0 2 / He = 1/2/4 / 7.5 ( molar ratio)

3) AN: acrylonitrile 4) C ₃ ': propylene 5) HCN: hydrogen cyanide

6) AN + Cs': sum of acrylonitrile and propylene

Table 2

As 1) a carrier, in all of Comparative Example _{_{_{A1 2 0 3: Si0 2 =}}} l: Using 1 (weight ratio).

2) Gas composition A:

1/2/4 / 7.5 / 3 (molar ratio)

3) AN: Acrylonitrile 4) C ₃ ': Propylene 5) HCN: Hydrogen cyanide 6) AN + Cs': the sum of acrylonitrile and propylene

Claims

The scope of the claims

1. According to the ammoxidation method, at least one saturated hydrocarbon selected from the group consisting of propane and isobutane is catalytically oxidized with a mixed gas containing molecular oxygen and ammonia in the presence of a catalyst.

5 In the method for producing nitrile,

The following general formula (I):

Moa S b 3WrOx (I)

(Where a β and 7 each represent the number of atoms of Mo, S b and W, and when is 1, / 3 is 0.5 to 10 and α is 0.5 to 10, and X is It is a value determined by the atomic valence of the element that exists.)

A method comprising using a catalyst comprising a composite oxide represented by the following formula 1 on a refractory inorganic carrier substance.

2. As a catalyst, at least one element selected from the group consisting of Nb, Cr, Mn, Fe, Co, and Ni, together with the constituent elements of the composite oxide represented by the general formula (I). 2. The method according to claim 1, wherein a catalyst comprising a composite oxide is used in such an amount that the atomic ratio of the element to Mo is more than 0 and 0.5 or less.

3. As a catalyst, a group consisting of V, Nb, Cr, Mn, Fe, Co and Ni, together with the component elements of the complex oxide represented by the general formula (I).

2o The amount of at least one selected element is such that the atomic ratio of the element to Mo is more than 0 and 0.5 or less, and the atomic ratio of the element to the sum of Mo and W is more than 0 and 0 2. The method according to claim 1, wherein a catalyst comprising the composite oxide is used in an amount of not more than 05.

4. ammoxidation of at least one saturated hydrocarbon selected from the group consisting of propane and isobutane to produce (meth) acrylonitrile;

The following general formula (I):

Mo «Sb / 3WrOx (I)

(Where α, / 3 and y represent the number of atoms of Mo, Sb and W, respectively, when is 1, 5 is 0.5 to 10, α is 0.5 to 10, and X is This value is determined by the valence of the element.)

A catalyst comprising a composite oxide represented by the following formula 1 supported on a refractory inorganic carrier substance.

5. At least one element selected from the group consisting of Nb, Cr, Mn, Fe, Co and Ni, together with the constituent elements of the composite oxide represented by the general formula (I) according to claim 4. 5. The catalyst according to claim 4, wherein a composite oxide containing an element in an amount such that the atomic ratio of the element to Mo is more than 0 and 0.5 or less is used.

6. At least one member selected from the group consisting of V, Nb, Cr, Mn, Fe, Co and Ni, together with the constituent elements of the composite oxide represented by the general formula (I) according to claim 4. Is an amount such that the atomic ratio of the element to Mo is greater than 0 and 0.5 or less, and the atomic ratio of the element to the sum of Mo and W is greater than 0 and 0.05 or less. 5. The catalyst according to claim 4, wherein the composite oxide is used in such an amount that: