JPH10128112A - Catalyst for vapor phase contact oxidation reaction of isobutane and its preparation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare an alkene such as isobutylene, methacrolein and methacrylic acid and an oxygen-contg. compd. from isobutane with high conversion rate and high selectivity by using a composite oxide catalyst wherein molybdenum-vanadium-antimony and/or tellurium are essential ingredients. SOLUTION: In preparing a catalyst used in preparation of an alkene and an oxygen-contg. compd., a precursor substance which can form a composite oxide of general formula MoaVbXcYdZeOf after calcination is treated by calcining it under inert gas atmosphere. In the formula, Mo, V, X, O, Y and Z are respectively molybdeum, vanadium, antimony or tellurium, oxygen, one element selected from arsenic, etc., and one element selected from potassium, etc., and in addition suffixes a-e are atomic ratios of each element and when a=12, (b) is a value of at most 6 except 0 and c is a value of at most 20 except 0 and (d) and (e) are each a value of at most 6 including 0 and f is a value determined by atomic valence and atomic ratio of each element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an industrially useful alkene such as isobutylene, acetic acid, acrylic acid, methacrolein and methacrylic acid and an oxygen-containing compound obtained by subjecting isobutane and molecular oxygen to gas phase catalytic oxidation. The present invention relates to a catalyst for a gas-phase catalytic oxidation reaction of isobutane used for producing a compound, and a method for producing the same.

[0002]

2. Description of the Related Art A method for producing methacrylic acid from isobutylene or tertiary butanol via methacrolein by two-step oxidation is well known and has already been industrialized. On the other hand, in recent years, a method for producing methacrolein or methacrylic acid by gas phase catalytic oxidation using isobutane, which is less expensive than isobutylene, as a raw material has been proposed.

For example, Japanese Patent Application Laid-Open No. 62-132832 discloses that “methacrylic acid and / or methacrolein are obtained by alternately contacting isobutane and oxygen with a catalyst containing a heteropolyacid containing phosphorus or arsenic as a central element and containing molybdenum. JP-A-2-42034 discloses that a heteropolyacid containing molybdenum containing phosphorus and / or arsenic as a central element and / or a salt thereof is made of Ag, Zn, CdT.
iZrNbTaCrWMnFeCoN
A mixed gas containing molecular oxygen containing isobutane is brought into contact with a catalyst containing at least one selected from the village consisting of iRhSnBi and Te as a catalyst constituent element to obtain methacrylic acid and / or methacrolein. Methods and the like are known. Further, Japanese Patent Application Laid-Open No. Hei 5-17877
No. 4 and JP-A-5-331085 disclose that in the production of methacrylic acid and / or methacrolein by catalytic gas-phase oxidation of isobutane in the presence of a catalyst, vanadyl pyrophosphate is used as a main component. There is disclosed a method characterized by using a composite oxide catalyst having improved activity and selectivity by adding another metal element such as gold or silver.

However, since isobutane has lower reactivity than isobutylene and the like, the conversion rate is low under the oxidation reaction conditions of isobutylene. Therefore, a method of raising the oxidation reaction temperature to increase the conversion is conceivable, but in this case, there is a drawback that excessive oxidation of methacrylic acid or methacrolein, which is the target substance, occurs, and the selectivity decreases. In addition, these phosphorus-molybdenum-based Keggin-type heteropolyacid catalysts have poor thermal stability, and have a problem in their thermal stability when used as a catalyst. In addition, when a composite oxide catalyst containing vanadyl pyrophosphate as a main component is used, a satisfactory selectivity improving effect cannot always be obtained.

[0005]

Under these circumstances, the present inventors have determined from isobutane to isobutylene, acetic acid,
As a result of intensive studies on the purpose of producing alkenes and oxygenated compounds such as acrylic acid, methacrolein and methacrylic acid with high conversion and high selectivity, molybdenum-vanazine was used as a catalyst for the gas phase catalytic oxidation reaction. -When a composite oxide catalyst containing antimony and / or tellurium as an essential component is used, it has been found that the catalyst has excellent heat resistance, and that conversion and selectivity are both excellent.
The present invention has been completed.

[0006]

That is, the present invention provides a compound represented by the general formula: MoaVbXcYdZeOf (where Mo is molybdenum, V is vanadium, X is antimony or tellurium,
O is oxygen, Y is at least one element selected from the group consisting of arsenic, boron and germanium, Z is potassium, cesium, rubidium, calcium, magnesium, thallium, chromium, manganese, iron, cobalt, nickel, copper, Represents at least one element selected from the group consisting of silver, bismuth, aluminum, gallium, indium, tin, zinc, lanthanum, cerium, yttrium, tungsten, niobium and tantalum, and subscripts a, b, c, d and e represents the atomic ratio of each element, and a = 1
When it is set to 2, b is a value of 6 or less not including 0, c is a value of 20 or less not including 0, d and e are values of 6 or less including 0, and f is a valence and an atomic ratio of each element. The present invention provides a catalyst for a gas phase catalytic oxidation reaction of isobutane comprising a composite oxide represented by the following formula:

[0007] Further, the present invention provides a method of the present invention, wherein
a complex oxide represented by aVbXcYdZeOf (in the formula,
Mo is molybdenum, V is vanadium, X is antimony or tellurium, O is oxygen, Y is at least one element selected from the group consisting of arsenic, boron and germanium,
Z is potassium, cesium, rubidium, calcium, magnesium, thallium, chromium, manganese, iron, cobalt, nickel, copper, silver, bismuth, aluminum, gallium, indium, tin, zinc, lanthanum, cerium,
Represents at least one element selected from the group consisting of yttrium, tungsten, niobium and tantalum, and the subscripts a, b, c, d and e represent the atomic ratio of each element,
When a = 12, b is a value of 6 or less not including 0, c
Is a value of 20 or less that does not include 0, and d and e are 6 that include 0
The following formula, where f represents a value determined by the valence and atomic ratio of each element), is fired in an inert gas atmosphere.
VbXcYdZeOf (the limitations in the formula are the same as described above)
And a method for producing a catalyst for gas-phase catalytic oxidation reaction of isobutane represented by the formula:

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The feature of the present invention is that gaseous catalytic oxidation of isobutane using molecular oxygen, isobutylene, methacrolein,
In producing an alkene and / or an oxygen-containing compound such as methacrylic acid, a catalyst to be applied includes a general formula Mo
Mo-V-Sb / Te represented by aVbXcYdZeOf (the symbols in the formula are the same as above) is an essential component, that is, when a = 12, b is 0 <b ≦ 6, preferably 0 <b ≦.
4, c is to provide a composite oxide having an atomic ratio of 0 <c ≦ 20, preferably 0 <c ≦ 12. In the present invention, a satisfactory catalytic effect, mainly an improvement in selectivity, is not observed even if any of these catalyst components is missing.

The catalyst of the present invention may exhibit more excellent catalytic performance by further containing other elements in its use. That is, in the general formula, Y is arsenic, boron,
At least one element selected from the group consisting of germanium, Z is potassium, cesium, rubidium, calcium, magnesium, thallium, chromium, manganese, iron,
At least one element selected from the group consisting of cobalt, nickel, copper, silver, bismuth, aluminum, gallium, indium, tin, zinc, lanthanum, cerium, yttrium, tungsten, niobium, and tantalum, and their atomic ratios When a = 12, d and e are 0 to
A catalyst containing 6, preferably in the range of 0 to 5 is excellent. If the amount of these catalyst components is larger than the above range, the catalytic performance will decrease.

The method for preparing the catalyst of the present invention is not particularly limited, and can be prepared by various known methods. For example,
A composite oxide catalyst composed of molybdenum, vanadium and antimony can obtain a predetermined catalyst by adding antimony trioxide to an aqueous solution composed of ammonium paramolybdate and ammonium metavanadate, drying and calcining. . Molybdenum, vanadium,
As the tellurium composite oxide-based catalyst, a predetermined catalyst can be obtained by adding an aqueous solution of telluric acid to an aqueous solution comprising ammonium paramolybdate and ammonium metavanadate, followed by drying and firing. As a molybdenum raw material, molybdenum trioxide, molybdic acid, ammonium paramolybdate, sodium molybdate and the like can be used, and as a vanadium raw material, besides pentavalent vanadium such as ammonium metavanadate, sodium vanadate, vanadium pentoxide and the like. And tetravalent vanadium such as vanadyl oxalate can also be used. The catalyst constituents of the present invention, including the elements represented by Y and Z in the above general formula, are compounds that can be decomposed into oxides during the catalyst preparation process, such as oxides, hydroxides, nitrates, ammonium salts, and carbonates. They are added and used as salts, chlorides, organic acid salts, ammonium metal salts and the like. The catalyst can be used in the form of a support and / or a dilute mixture. As the carrier and / or diluent, for example, silica, alumina, silica-alumina, magnesia, titania, zeolite, zirconia,
Silicon-carbide and the like are mentioned, and there is no limitation on the amount of the carrier and the dilution mixture ratio of the diluent and the catalyst. The shape of the catalyst is not limited to tablets, rings, spheres, extruded products, and the like. The molding method can be performed by a known method such as compression molding, extrusion molding, spray drying granulation and the like. Baking is about 400 ° C to about 650
It is carried out at a temperature of ° C. in an oxygen atmosphere or an inert gas atmosphere using nitrogen gas or the like. In particular, calcination in an inert gas atmosphere can provide a catalyst with improved catalytic performance as compared to calcination in an oxygen atmosphere. The catalyst thus obtained is suitable for the gas-phase catalytic oxidation reaction of isobutane.

In the gas-phase catalytic oxidation reaction of isobutane using the catalyst of the present invention, the raw material gas used for the reaction includes:
Isobutane and molecular oxygen are used. The isobutane concentration in the feed gas is about 1 mol% to about 85 mol%, preferably about 3 mol% to about 70 mol%.

The molar ratio of molecular oxygen to isobutane is from about 0.05 to about 4.0, preferably from about 0.1 to about 3.5.
Is appropriate. As a supply source of molecular oxygen, air, pure oxygen, oxygen-enriched air, or the like is used.

Although steam may be contained in the reaction raw material gas, steam is not always required.

The source gas may contain a noble gas, nitrogen, carbon monoxide, carbon dioxide or the like. Further, even if isobutylene is contained in the raw material, isobutylene is converted to methacrolein or methacrylic acid as in isobutane.

Unreacted isobutane can be used as fuel, but can also be recovered and recycled. Isobutylene and methacrolein can also be converted to methacrylic acid by collecting and recycling. When pure oxygen or oxygen-enriched air is used, it is preferable that unreacted oxygen is also collected and reused.

[0016] The reaction temperature can be selected in the range of about 300 to about 550 ° C, but is preferably about 330 to about 500 ° C. The reaction pressure can be selected from a wide range from reduced pressure to increased pressure, but is usually about 100 to about 400 kPa, preferably about 100 to about 20 kPa.
The range is 0 kPa.

The reaction using the catalyst of the present invention can be carried out in any reaction mode such as a fixed bed, a moving bed and a fluidized bed. When using the fixed floor method, there is no particular limitation on the space velocity,
If the space velocity is too low, productivity is reduced, which is industrially disadvantageous. Conversely, if the space velocity is too high, the reaction activity will decrease, so the reaction temperature must be increased.
Thus, it is usually in the range of about 400 to about 5000 / hr, preferably about 600 to about 2000 / hr. The alkenes and various oxygen-containing compounds thus produced can be separated and purified into respective products by operations such as extraction and distillation.

[0018]

According to the present invention described in detail above, the activity of the catalyst is high and the selectivity to alkenes and oxygen-containing compounds such as isobutylene, methacrolein and methacrylic acid is high. And an oxygen-containing compound can be produced.

[0019]

Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.
The conversion (%) and the selectivity (%) were defined as follows. Isobutane conversion (%) = (moles of reacted isobutane) ÷ (moles of supplied isobutane) × 100 Isobutylene selectivity (%) = (moles of generated isobutylene) ÷ (moles of reacted isobutane) × 100 methacrolein selectivity (%) = (mol number of generated methacrolein) ÷ (mol number of reacted isobutane) × 10
0 Selectivity of methacrylic acid (%) = (mol number of methacrylic acid generated) / (mol number of reacted isobutane) × 100 Selectivity of active ingredient (%) = (mol number of generated isobutylene + methacryloline generated) Number of moles of methacrylic acid generated) / (number of moles of reacted isobutane)
× 100) The reaction product was analyzed using gas chromatography.

Example 1 Niobium hydrogen oxalate @ Nb was added to 800 ml of ion-exchanged water.
(HC_TwoO_Four)_Five・ NH _TwoO｝ 141.96 g was added and stirred.
After stirring and dissolving, a vanadium concentration of 2 mol / l
Add 150 ml of vanadyl acid aqueous solution to obtain a uniform aqueous solution.
(Solution A). Then add paramo to 300 ml of ion-exchanged water.
Ammonium lybdate ｛((NH_Four)₆Mo₇O_{twenty four}・
4H_TwoO)｝ 212.10 g was added and dissolved by stirring (B
Solution), then inject the entire amount of solution B into solution A, and further add antimony trioxide.
(Sb_TwoO_Three) 131.24 g was added and the mixture
Add 25% aqueous ammonia to the water and adjust the pH to almost neutral.
Was. The slurry solution thus obtained is heated and stirred.
Concentrate to dryness while drying at 120 ° C for 14.5 hours
And crushing and sieving to obtain 4-8 mesh particles,
Mo is fired at 600 ° C for 2 hours in a nitrogen stream.₁₂V_ThreeSb₉
Nb_1.5O_XA catalyst having the following composition was obtained. Like this
6g of the catalyst obtained from Pyrex glass with a diameter of 15mm
Fill a reaction tube, add isobutane / oxygen / nitrogen / water vapor
The ratio (molar%) of qi is 25/12/33/30
Source gas is supplied, reaction pressure is 152 kPa, space velocity is 10
When the oxidation reaction was performed by heating under the condition of 00 / hr,
The conversion of isobutane at a reaction temperature of 425 ° C. is 6.3.
%, Isobutylene, methacrolein and methacrylic acid
Selectivity is 11.9%, 23.8% and 7.8% respectively
Met. Reaction temperature (reactor wall temperature) 400-450 ° C
Of the isobutane conversion rate of 5%
The selectivity to the active ingredient was 47.5%.

Example 2 A catalytic oxidation reaction was carried out in the same manner as in Example 1 except that the ratio (mol%) of isobutane / oxygen / nitrogen was 37/17/46 as the raw material gas. As a result, the isobutane conversion at a reaction temperature of 425 ° C. was 6.2%, and the selectivities of isobutylene, methacrolein and methacrylic acid were 15.6%, 21.2% and 4.5%, respectively. The selectivity to the active ingredient at a reaction temperature of 400 to 450 ° C. and an isobutane conversion of 5% was 45.0%.

Example 3 Instead of niobium hydrogen oxalate, niobium pentoxide @ Nb ₂ O
A catalyst having the same composition was prepared in the same manner as in Example 1 except that ₅ % was used. Using this catalyst, a reaction was carried out under the same conditions as in Example 1. As a result, the conversion of isobutane at a reaction temperature of 425 ° C. was 6.5%, and the selectivities of isobutylene, methacrolein and methacrylic acid were 11.0, respectively.
%, 16.7% and 3.1%. The selectivity to the active ingredient at a reaction temperature of 400 to 450 ° C. and a conversion of isobutane of 5% was 32.3%.

Example 4 In the method of Example 1, antimony trioxide (Sb ₂ O
₃ ) M was changed in the same manner as in Example 1 except that the amount of addition was changed.
A catalyst having a composition of o ₁₂ V ₃ Nb _1.5 Sb ₆ Ox was obtained. Using this catalyst, a reaction was carried out under the same conditions as in Example 1. As a result, the conversion of isobutane at a reaction temperature of 425 ° C. was 4.9%, and the selectivities of isobutylene, methacrolein and methacrylic acid were 21.5% and 10.7%, respectively.
% And 1.9%. Further, the reaction temperature is 400 to 45.
The selectivity to the active ingredient at a conversion of isobutane of 5% at 0 ° C. was 34.0%.

[0024] Example 5 Ion-exchanged water 150ml into ammonium paramolybdate _{{((NH 4) 6 Mo} 7 O 24 · 4H 2 O)} 53.0
After adding 5 g and stirring and dissolving, the vanadium concentration was 1 mol /
Then, 75 ml of an aqueous solution of vanadyl oxalate ( ₁ ) was added, and then 32.80 g of antimony trioxide (Sb ₂ O ₃ ) was added. 25% ammonia water is added to this mixture to adjust the pH.
Was adjusted to almost neutral. The slurry solution thus obtained is concentrated to dryness while heating and stirring, and further dried at 120 ° C. for 3 hours, and pulverized and sieved to obtain 4 to 8 mesh particles. Mo ₁₂ was fired for 2 hours
A catalyst having a composition of V ₃ Sb ₉ Ox was obtained. Using this catalyst, an oxidation reaction was performed under the same conditions as in Example 1.
The isobutane conversion at a reaction temperature of 425 ° C was 2.2.
%, Isobutylene, methacrolein and methacrylic acid selectivities of 23.6%, 26.2% and 3.7%, respectively.
Met. The selectivity to the active ingredient at a reaction temperature of 400 to 450 ° C. and a conversion of isobutane of 5% was 44.4%.

Example 6 Mo ₁₂ V ₃ S was prepared in the same manner as in Example 1 except that germanium dioxide (GeO ₂ ) was added to the solution A of Example 1.
A catalyst having a composition of b ₉ Nb _1.5 Ge ₃ Ox was obtained. When an oxidation reaction was carried out using this catalyst under the same conditions as in Example 2, the conversion of isobutane at a reaction temperature of 425 ° C. was 2.9%, and the selectivity of isobutylene, methacrolein and methacrylic acid was 34. 1%, 18.4% and 0.6%. When the isobutane conversion is 5% at a reaction temperature of 400 to 450 ° C., the selectivity to the active ingredient is 47.
9%.

Example 7 Tin solution [Sn (CH ₃ CO ₃₎
O) ₂ ] was added in the same manner as in Example 1 except that M) was added.
A catalyst having a composition of o ₁₂ V ₃ Sb ₉ Nb _1.5 Sn ₃ Ox was obtained. When an oxidation reaction was carried out using this catalyst under the same conditions as in Example 2, the conversion of isobutane at a reaction temperature of 425 ° C. was 7.4%, and the selectivities of isobutylene, methacrolein and methacrylic acid were each 8. 7%, 21.
8% and 3.8%. Reaction temperature 400-450 ° C
Was 42.2% when the isobutane conversion was 5%.

Example 8 In solution A of Example 1, iron nitrate [Fe (NO ₃ ) .9H ₂ O
Except that Mo ₁₂ V ₃ was added in the same manner as in Example 1.
A catalyst having a composition of Sb ₉ Nb _1.5 Fe ₃ Ox was obtained.
When an oxidation reaction was carried out using this catalyst under the same conditions as in Example 2, the isobutane conversion at a reaction temperature of 425 ° C. was 7.5%, and the selectivity of isobutylene, methacrolein and methacrylic acid was 13. 7%, 17.2% and 2.3%. At a reaction temperature of 380 to 450 ° C., the selectivity to the active ingredient at a conversion of isobutane of 5% is 3
7.5%.

Example 9 In Example 1, ammonium metavanadate {NH ₄ VO ₃ } was used instead of vanadyl oxalate, and Sb ₂ O
A catalyst having a composition of Mo ₁₂ V _3.6 Te _2.8 Nb _1.4 Ox was obtained in the same manner as in Example 1 except that H ₆ TeO ₆ was used instead of ₃ . Using this catalyst, the reaction temperature was 35
When the oxidation reaction was carried out under the same conditions as in Example 1 except that the temperature was changed to 0 ° C., the conversion of isobutane at a reaction temperature of 350 ° C. was 4.9%, and the selectivities of isobutylene, methacrolein and methacrylic acid were respectively 4.3%, 13.9% and 11.8%. At a reaction temperature of 330 to 400 ° C., the selectivity to the active ingredient at an isobutane conversion of 5% is 3
0.0%.

Example 10 The dried slurry obtained in Example 3 was dried in air.
It was baked at 600 ° C. for 2 hours. The reaction was carried out under the same reaction conditions as in Example 1 except that the reaction temperature was 330 ° C. using this catalyst, and the conversion of isobutane was 4.8%. At this time, selectivities of isobutylene, methacrolein and methacrylic acid were 1.4%, 16.2% and 5.7%, respectively. At a reaction temperature of 290 to 350 ° C., the selectivity to the active ingredient when the isobutane conversion is 5% is 2
2.9%.

Comparative Example 1 A composite oxide catalyst having the experimental composition Mo ₁₂ V ₃ Ox (x represents a value determined by the valence and atomic ratio of each element) was prepared by the following method. Ion exchange water 120
Add 0 ml of ammonium paramolybdate ｛((NH ₄ )
_{6 Mo 7 O 24 · 4H 2} O)} was added 211.9G, After stirring and dissolution. Added vanadyl oxalate solution 300ml vanadium concentration of 1 mol / l, were mixed, medium PH of the mixed solution Aqueous 25% ammonia was added to make it more acidic. Thereafter, the water was evaporated in a dryer at 120 ° C., which was baked at 600 ° C. for 3 hours in a nitrogen stream. Using this catalyst, an oxidation reaction was carried out under the same conditions as in Example 1 except that the reaction temperature was 350 ° C. At a reaction temperature of 350 ° C, the conversion of isobutane was 5.0%, The selectivities of rhein and methacrylic acid were 6.7%, 3.1% and 0.7%, respectively. Isobutane conversion rate 5% at a reaction temperature of 310 to 350 ° C
At that time, the selectivity to the active ingredient was 10.6%.

Comparative Example 2 Niobium hydrogen oxalate @ Nb was added to 400 ml of ion-exchanged water.
(HC_TwoO_Four)_Five・ NH _TwoAdd 35.59 g of O and stir
After dissolution, oxalic acid with a vanadium concentration of 1 mol / l
75 ml of vanadyl aqueous solution was added to make a uniform aqueous solution.
(Solution A). Then add paramolyb to 150 ml of deionized water.
Ammonium denate ｛((NH_Four)₆Mo ₇O_{twenty four}・ 4H
_TwoO) $ 53.00 g was added and dissolved by stirring (Solution B)
Thereafter, the entire amount of the solution B was injected and mixed into the solution A, and 25%
Aqueous ammonia was added to adjust the pH to almost neutral. This
The resulting slurry solution was concentrated and dried while heating and stirring.
Hardened, further dried at 120 ° C for 14.5 hours, pulverized and sieved
Separately, particles of 4 to 8 mesh were obtained,
Baking at 00 ° C for 2 hours, Mo₁₂V_ThreeNb_1.5O_XComposition of
Was obtained. Using this catalyst, the reaction temperature was 29
The oxidation reaction was carried out under the same conditions as in Example 1 except that the temperature was 0 ° C.
The isobutane at a reaction temperature of 290 ° C.
The conversion is 7.2%, isobutylene, methacrolein and
The selectivity of methacrylic acid was 5.1%, 1.9%, respectively.
And 1.1%. At a reaction temperature of 250-300 ° C
When the isobutane conversion is 5%, the selectivity to the active ingredient is 9.
3%.

Comparative Example 3 27.8 g of hydroxylamine hydrochloride (NH ₂ OH / HCI) and 400% phosphoric acid (H) were added to 400 ml of ion-exchanged water.
_After dissolving 58.8 g of ₃ PO ₄ ) to form a uniform solution,
Heated to 80 ° C. with a hot stirrer. To this solution, 36.4 g of vanadium pentoxide (V ₂ O ₅ ) was gradually added. Stirring was continued for about 6 hours after the completion of the addition of vanadium pentoxide, and the resultant was dried in a dryer at 120 ° C. for 15 hours to evaporate water. The obtained dried product was calcined at 500 ° C. for 15 hours to obtain a catalyst having a composition of (VO) ₂ P ₂ O ₇ . 9 g of the catalyst obtained by the above method was charged into a Pyrex glass reaction tube having a diameter of 15 mm, and isobutane /
Oxygen / nitrogen / water vapor ratio (mol%) is 47/36/1
7/0 source gas is supplied and the reaction pressure is 152 kP
a, When the oxidation reaction was carried out by heating at a space velocity of 1000 / hr, the isobutane conversion at a reaction temperature of 360 ° C. was 2.1%, and the selectivities of isobutylene, methacrolein and methacrylic acid were 1.7, respectively. %, 2.5
%, 8.8%.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI B01J 27/057 B01J 27/057 Z C07B 61/00 300 C07B 61/00 300 C07C 11/09 C07C 11/09 27/12 310 27 / 12 310 47/22 47/22 B 57/05 57/05

Claims (3)

[Claims] 1. General formula MoaVbXcYdZeOf (where Mo is molybdenum, V is vanadium, X is antimony or tellurium, O is oxygen, Y is at least one element selected from the group consisting of arsenic, boron and germanium, Z is potassium, cesium, rubidium, calcium, magnesium, thallium, chromium, manganese,
Iron, cobalt, nickel, copper, silver, bismuth, aluminum, gallium, indium, tin, zinc, lanthanum,
When at least one element selected from the group consisting of cerium, yttrium, tungsten, niobium and tantalum is represented, and subscripts a, b, c, d and e represent the atomic ratio of each element, and when a = 12 , B is a value of 6 or less not including 0, c is a value of 20 or less not including 0, d and e are values of 6 or less including 0, and f is a value determined by the valence and atomic ratio of each element. A catalyst for a gas phase catalytic oxidation reaction of isobutane, comprising a composite oxide represented by the formula (1). 2. After firing, the general formula MoaVbXcYdZ
a complex oxide represented by eOf (where Mo is molybdenum, V is vanadium, X is antimony or tellurium, O
Is oxygen, Y is at least one element selected from the group consisting of arsenic, boron and germanium, Z is potassium,
Cesium, rubidium, calcium, magnesium, thallium, chromium, manganese, iron, cobalt, nickel,
Copper, silver, bismuth, aluminum, gallium, indium, tin, zinc, lanthanum, cerium, yttrium,
Represents at least one element selected from the group consisting of tungsten, niobium, and tantalum;
c, d and e represent the atomic ratio of each element, and when a = 12, b is a value of 6 or less not including 0, c is a value of 20 or less not including 0, and d and e include 0 6 or less, f represents a value determined by the valence and atomic ratio of each element)
Wherein the precursor substance capable of forming the compound is calcined in an inert gas atmosphere. The general formula: MoaVbXcYdZ
A method for producing a catalyst for gas-phase catalytic oxidation reaction of isobutane represented by eOf (the description in the formula is the same as described above). 3. The method for producing a catalyst for gas phase catalytic oxidation reaction of isobutane according to claim 2, wherein the inert gas atmosphere is a nitrogen atmosphere.