JPH06170232A - Catalyst for synthesis of unsaturated aldehyde and unsaturated carboxylic acid and it use - Google Patents

Abstract

PURPOSE:To provide a catalyst of a special shape for advantageous production of corresponding unsatd. aldehyde from propylene, isobutylene, tert. butanol or tert. butyl ether. CONSTITUTION:This catalyst is a cylindrical Mo-Bi-Fe catalyst having a through hole. One of the outer and inner circumferences of the cross section is an ellipse, the other is a circle, the center of the ellipse coincides with that of the circle and the ratio of the major axis size of the ellipse to the minor axis size is 1.2-4.0. Since this catalyst has such a shape as to minimize pressure drop even if this catalyst is broken by a shock at the time of packing, the yield of unsatd. aldehyde can be enhanced.

Description

Detailed Description of the Invention

[0001]

The present invention relates to propylene, isobutylene, tertiary butyl alcohol (hereinafter abbreviated as TBA) or methyl tertiary butyl ether (hereinafter abbreviated as MTBE) by molecular gas and gas phase catalytic oxidation. , The shape of the catalyst used in the synthesis of the corresponding unsaturated aldehyde and unsaturated carboxylic acid.

[0002]

2. Description of the Related Art Conventionally, a catalyst used in the vapor phase catalytic oxidation of propylene to produce acrolein and acrylic acid, and a vapor phase catalytic oxidation of isobutylene, TBA or MTBE to produce methacrolein and methacrylic acid. Many proposals have been made regarding the shape of the catalyst used in the above. For example, there are reports such as JP-A-59-46132.

In the above-mentioned gas phase catalytic oxidation in a fixed bed, the following are generally known. (1) It is known that the shape of the catalyst and the size of the catalyst body affect the pressure drop of the catalyst deposit, and the increased pressure drop adversely affects the selectivity of the desired product. Therefore, the shape having the through hole has a small pressure drop and is excellent in this respect. (2) Internal structure of catalyst body (porosity, length of diffusion path)
Decisively determines the mass transport and heat transport in the catalyst, and at the same time has a decisive influence on the selectivity together with the composition of the catalytically active substance. Generally, in the internal structure of the catalyst body, the larger the pore volume and / or the surface area, the better the selectivity.

With respect to (1), however, the shape having through-holes has a lower mechanical strength of the catalyst body than the shape having no through-holes, and breaks during handling or use, resulting in breakage of catalyst particles and fine particles. On the contrary, as a result of increased dust, the pressure drop is increased, which adversely affects the selectivity. In particular, the concentric ring-shaped structure is often divided into four as shown in FIG. 3 when it breaks during handling or use. The small pieces of the quartet of catalyst increase the pressure drop and adversely affect the selectivity. Regarding (2), in order to increase the pore volume and / or the surface area in the internal structure of the catalyst body, the density of the catalyst body (weight of catalyst body / volume of catalyst body) may be reduced. However, in molybdenum, bismuth, and iron-based catalysts, the lower the density, the lower the mechanical strength of the catalyst body. This causes a pressure drop as in (1). The contradiction between the two exists as a real problem, and it is currently strongly desired to solve it.

[0005]

It is extremely difficult to fundamentally solve the contradiction existing in the prior art. Also, when using a catalyst having through holes, it must be expected that the catalyst will break during handling or use to generate small pieces of catalyst particles. The present invention provides an unsaturated aldehyde and an unsaturated carboxylic acid which, when using a catalyst having a through hole, minimizes the pressure drop even if a small particle of the catalyst particle is broken during handling or during use. The purpose of the present invention is to provide a new catalyst shape of a catalyst for acid synthesis.

[0006]

In the concentric ring-shaped structure, the mechanical strength of the catalyst body is excellent in the direction perpendicular to the cross section, but the mechanical strength is small in the direction perpendicular to the side surface. Moreover, when it breaks in the direction perpendicular to this side surface, it is often divided into four as shown in FIG. This comes from a concentric ring-shaped structure, and when divided into four, the catalyst gap is reduced, and small fragments, fine powder and dust are generated, resulting in a pressure drop. Therefore, by giving a structurally weak portion to the concentric ring-shaped structure in advance, by increasing excessive force in the direction perpendicular to the side surface and breaking it, it is often divided into two.
It is believed that the above contradiction can be resolved by minimizing the generation of small pieces, fines and dust and reducing the increase in pressure drop.

The present invention relates to propylene, isobutylene, T
In a catalyst containing at least molybdenum, bismuth and iron, which is used in the gas phase catalytic oxidation of BA or MTBE with molecular oxygen to synthesize the corresponding unsaturated aldehyde and unsaturated carboxylic acid, the catalyst shape Has a cylindrical shape having a through hole, and the cross section has either an outer circumference or an inner circumference having an essentially elliptical shape, and the other has a circle, and the centers of the outer circumference and the inner circumference coincide with each other. ,
The present invention relates to a catalyst for synthesizing unsaturated aldehydes and unsaturated carboxylic acids, characterized in that the ratio of the longest distance to the shortest distance on the elliptical shape from the center is 1.2 to 4.0 and its use. The essentially elliptical shape according to the present invention means not only an ellipse based on mathematical grounds, but also an essentially elliptical shape that can inscribe a rectangle and an essentially elliptical shape that can circumscribe a rhombus. It also includes.

In the present invention, when the ratio of the longest distance to the shortest distance on the elliptical shape essentially from the center is less than 1.2, it is almost the same as the concentric ring-like shape and is excessive in the direction perpendicular to the side surface. When a force is applied to, there are many cases where it is divided into four, and the effect of the present invention is not obtained. On the other hand, if the ratio exceeds 4.0, the proportion of the through holes in the catalyst cross section decreases, and the effect of the through holes, such as reduction of pressure drop or improvement of diffusion efficiency, decreases.

In the present invention, it is important that either the outer circumference or the inner circumference has a through hole and has an essentially elliptical shape, and the other is a circle. Either the outer circumference or the inner circumference essentially has an elliptical shape, so that when a force is excessively applied in a direction perpendicular to the side surface, a structurally weak portion is cracked (FIGS. 1 and 2). In other words, since it is often divided into two, the reduction of the catalyst gap and the generation of small fragments, fine powder and dust can be minimized.

In the present invention, when the outer circumference is essentially elliptical (FIG. 1), the ratio of the shortest distance on the outer circumference to the radius of the inner circumference from the center is preferably 1.1 to 8.0.
If this ratio is less than 1.1, the mechanical strength in the direction perpendicular to the side surface is significantly reduced, which is not preferable. Further, if this ratio exceeds 8.0, the proportion of the through holes in the cross section of the catalyst body decreases, and the effects of the through holes such as reduction of pressure drop and improvement of diffusion efficiency are reduced, which is not preferable. . Conversely, even when the inner circumference is essentially elliptical (FIG. 2), the ratio of the radius of the outer circumference to the longest distance on the inner circumference from the center is preferably 1.1 to 8.0. If this ratio is less than 1.1, the mechanical strength in the direction perpendicular to the side surface is significantly reduced, which is not preferable. On the other hand, when it exceeds 8.0, the ratio of the through holes of the catalyst body decreases, and the effect of the central hole such as reduction of pressure drop or improvement of diffusion efficiency is reduced, which is not preferable.

In the present invention, the length (height) of the catalyst body is preferably 1.0 to 5.0 times the shortest distance on the outer circumference from the center. When the length of the catalyst is less than 1.0 times the shortest distance on the outer circumference from the center, the mechanical strength of the catalyst body is significantly reduced, which is not preferable. Further, if the length exceeds 5.0 times the shortest distance on the outer circumference from the center, the effect of the through hole such as the improvement of diffusion efficiency is reduced, which is not preferable.

In the present invention, in the shape of the catalyst, specifically, the shortest distance from the center of the catalyst cross section to the outer periphery is 1 to 10.
The range of mm and the length of 2 to 15 mm is preferable. In the present invention, the method of shaping is not particularly limited,
Molding can be performed using a general powder molding machine such as a tablet molding machine or an extrusion molding machine. Further, in the present invention, conventionally known additives when shaping, for example, polyvinyl alcohol,
Carboxymethyl cellulose, inorganic fibers and the like may be added.

The present invention has the general formula Mo _a Bi _b Fe _c A _d X _e Y _f Z _g Si _h O _i (wherein Mo, Bi, Fe, Si and O are molybdenum, bismuth, iron, silicon and oxygen, respectively). And A is at least 1 selected from the group consisting of cobalt and nickel.
X represents at least one element selected from the group consisting of chromium, lead, manganese, calcium, magnesium, niobium, silver, barium, tin, tantalum and zinc, and Y represents phosphorus, boron, Z represents at least one element selected from the group consisting of sulfur, selenium, tellurium, cerium, tungsten, antimony and titanium, and Z
Is at least 1 selected from the group consisting of lithium, sodium, potassium, rubidium, cesium and thallium.
Indicates the element of the species. a, b, c, d, e, f, g, h and i represent the atomic ratio of each element, and when a = 12, b = 0.0
1-3, c = 0.01-5, d = 1-12, e = 0
8, f = 0 to 5, g = 0.001 to 2, h = 0 to 20 and i is the number of oxygen atoms required to satisfy the valence of each component. A catalyst having a composition represented by) can be used.

The method for producing the catalyst used in the present invention does not need to be limited to a special method, and as long as there is no significant uneven distribution of the components, the well-known evaporation dryness method, precipitation method, Various methods such as an oxide mixing method can be used. As the raw material of the catalyst component, a combination of oxides, sulfates, nitrates, carbonates, hydroxides, ammonium salts, halides and the like of each element can be used. For example, as a molybdenum raw material, ammonium paramolybdate, molybdenum trioxide, or the like can be used.

In carrying out the present invention, molecular oxygen is added to propylene, isobutylene or TBA as a raw material, and gas phase catalytic oxidation is carried out in the presence of the above catalyst. propylene,
The molar ratio of isobutylene or tertiary butanol to oxygen is 1:
0.5-3 is preferable. The raw material gas is preferably diluted with an inert gas before use. It is economical to use air as the oxygen source, but if necessary, air enriched with pure oxygen can also be used. The reaction pressure is preferably atmospheric pressure to several atmospheres.
The reaction temperature can be selected in the range of 200 to 450 ° C, but the range of 250 to 400 ° C is particularly preferable.

[0016]

EXAMPLES The method for producing the catalyst according to the present invention and the reaction examples using the same will be specifically described below. Reaction rates of raw material olefins, TBA and MTBA in Examples and Comparative Examples,
The selectivity of the unsaturated aldehyde and unsaturated carboxylic acid produced is defined as follows.

[0017]

[Equation 1]

Further, the filling powdering rate and the shape change rate of the molded catalyst are defined as follows. 100 parts of the molded catalyst is weighed, and the number of molded catalysts is X at this time. Next, a weighed molded catalyst is filled from the upper portion of the stainless steel tube into a stainless steel tube having an inner diameter of 30 mmφ and a length of 5 m installed vertically to the horizontal direction, and after the filling, the recovered catalyst is collected from the lower portion of the stainless steel tube. Of the recovered catalysts, the catalyst a part which does not pass through the 8-mesh sieve and the number of catalysts which did not pass through the 8-mesh sieve at this time is Y, and the packing powdering rate and the shape change rate are Is represented as follows.

[0019]

[Equation 2]

In the following Examples and Comparative Examples, parts are parts by weight, and analysis was by gas chromatography.

Example 1 Ammonium paramolybdate 500 was added to 1000 parts of water.
Parts, 43.1 parts of ammonium paratungstate and 1.4 parts of potassium nitrate were added and heated and stirred (Liquid A). Separately, 41.9 parts of 60% nitric acid was added to 600 parts of water to make the mixture uniform, and then 114.5 parts of bismuth nitrate was added and dissolved. To this, 95.3 parts of ferric nitrate, 309.0 parts of cobalt nitrate and 7.0 parts of zinc nitrate were sequentially added, and 400 parts of water was further added and dissolved (solution B). Liquid B was added to liquid A to make an aqueous slurry, 24.1 parts of antimony trioxide was added, and the mixture was heated with stirring and then evaporated to dryness to obtain a cake-like substance. After drying the obtained cake-like substance at 130 ℃, 300 ℃ under air atmosphere
It was baked for 1 hour. After adding 35 parts of water to 100 parts of the obtained baked powder and kneading the mixture, with an extruder, the outer circumference is elliptical and the longest distance from the center is 3.0 mm, the shortest distance is 2.5 mm, and the inner diameter is 1 It was extruded into a concentric cylinder having a through hole of 0.0 mm and an average length of 5.0 mm. The shaped catalyst was dried at 130 ° C. for 6 hours and then heat-treated again at 500 ° C. for 6 hours in an air atmosphere to be used as a catalyst.

The composition of elements other than oxygen in the obtained catalyst (the same applies hereinafter) was Mo ₁₂ W _0.3 Bi ₁ Fe ₁ Zn _0.1 Co _4.5.
It was K _0.06 Al _0.1 Si ₅ . This catalyst was filled in a stainless steel reaction tube, and a raw material mixed gas of propylene 5%, oxygen 12%, water vapor 10% and nitrogen 73% (volume%) was passed through the catalyst layer at a contact time of 3.6 seconds to obtain 310 ° C. It was made to react with. As a result, the reaction rate of propylene was 99.2%, the selectivity of acrolein was 90.3%, and the selectivity of acrylic acid was 6.2.
%Met. In addition, the filling powder ratio was 1.6% and the shape change ratio was 7.1%.

Example 2 In Example 1, the outer circumference was elliptical and the longest distance from the center was 2.0 mm, the shortest distance was 1.5 mm, and the inner diameter was 0.5 mm.
The heat treatment and the reaction were performed in the same manner as in Example 1 except that the through hole was formed into a concentric circular cylinder having an average length of 5.0 mm. As a result, the reaction rate of propylene was 99.3.
%, Acrolein selectivity was 90.4%, and acrylic acid selectivity was 6.3%. In addition, the filling powder ratio was 1.2% and the shape change ratio was 6.7%.

Example 3 In Example 1, the outer circumference is elliptical and the longest distance from the center is 3.5 mm, the shortest distance is 1.0 mm, and the inner diameter is 0.5 mm.
The heat treatment and the reaction were performed in the same manner as in Example 1 except that the through hole was formed into a concentric cylinder having an average length of 3.0 mm. As a result, the reaction rate of propylene was 99.2.
%, Acrolein selectivity was 90.1%, and acrylic acid selectivity was 6.3%. In addition, the filling powder ratio was 1.7% and the shape change ratio was 6.5%.

Example 4 In Example 1, the inner circumference was elliptical, the outer diameter had a radius of 2.5 mm, and the through hole had a maximum distance of 1.5 mm from the center and a minimum distance of 0.5 mm. Heat treatment and reaction were carried out in the same manner as in Example 1 except that the shape of the cylinder was concentric with an average length of 3.0 mm. As a result, the reaction rate of propylene was 99.2%, the selectivity of acrolein was 90.2%,
The selectivity of acrylic acid was 6.3%. In addition, the filling powder ratio was 0.9% and the shape change ratio was 6.2%.

Example 5 In Example 1, the inner circumference was elliptical, the outer diameter had a radius of 3.0 mm, and the through hole had a maximum distance of 1.5 mm from the center and a minimum distance of 1.0 mm. Heat treatment and reaction were performed in the same manner as in Example 1 except that the shape of the cylinder was concentric with an average length of 8.0 mm. As a result, the reaction rate of propylene was 99.2%, the selectivity of acrolein was 90.3%,
The selectivity of acrylic acid was 6.2%. In addition, the filling powder ratio was 1.4% and the shape change ratio was 7.4%.

Example 6 In Example 1, the inner circumference was elliptical, the outer diameter had a radius of 3.5 mm, and the through hole had a maximum distance of 3.0 mm from the center and a minimum distance of 0.5 mm. Heat treatment and reaction were performed in the same manner as in Example 1 except that the shape of the cylinder was concentric with an average length of 5.0 mm. As a result, the reaction rate of propylene was 99.3%, the selectivity of acrolein was 90.1%,
The selectivity of acrylic acid was 6.3%. In addition, the filling powder ratio was 1.6% and the shape change ratio was 8.0%.

Comparative Example 1 In Example 1, the outer circumference is elliptical, the longest distance from the center is 4.0 mm, the shortest distance is 3.7 mm, and the inner diameter is 0.5 mm.
The heat treatment and the reaction were performed in the same manner as in Example 1 except that the through hole was formed into a concentric circular cylinder having an average length of 5.0 mm. As a result, the reaction rate of propylene was 98.9.
%, Acrolein selectivity was 89.8%, and acrylic acid selectivity was 5.9%. In addition, the filling powder ratio was 0.5% and the shape change ratio was 5.9%.

Comparative Example 2 The same as Example 1 except that the outer circumference was 3.0 mm, the inner circumference was 1.0 mm, and the average length was 5.0 mm. Heat treatment and reaction were performed. As a result, the reactivity of propylene was 99.0%, the selectivity of acrolein was 89.7%, and the selectivity of acrylic acid was 6.0%. In addition, the filling powder ratio was 3.9% and the shape change ratio was 10.9%.

Example 7 To 400 parts of water was added 42 parts of 60% nitric acid to make a uniform solution, and then 68.7 parts of bismuth nitrate were added and dissolved. 274.5 parts of nickel nitrate and 24.1 of antimony trioxide
Parts were sequentially added and dissolved and dispersed. 165 parts of 28% ammonia water was added to this mixed solution to obtain a white precipitate and a blue solution. This was heated and stirred, and most of the water was evaporated. After drying the obtained slurry-like substance at 120 ° C. for 16 hours,
It was heat-treated at 750 ° C. for 2 hours and pulverized to obtain fine powder of bismuth-nickel-antimony.

Ammonium paramolybdate, 500 parts, and ammonium paratungstate, in 1000 parts of water 18.
5 parts and 20.7 parts of cesium nitrate were added, and the mixture was heated and stirred (Liquid A). Separately, in 700 parts of water, 190.7 parts of ferric nitrate,
Cobalt nitrate 137.3 parts and magnesium nitrate 12
1.0 part was sequentially added and dissolved (solution B). Solution B was added to solution A to form a slurry, and then 354.5 parts of 20% silica sol and the fine powder of the bismuth-nickel-antimony compound were added and heated and stirred to evaporate most of the water.

The obtained cake-like substance was dried at 130 ° C., and then calcined in an air atmosphere at 300 ° C. for 1 hour to be pulverized. After adding 30 parts of water to 100 parts of the obtained fired and pulverized product and kneading the mixture, with an extruder, the outer circumference is elliptical, the longest distance from the center is 2.5 mm, and the shortest distance is 2.0 mm.
It was extruded into a concentric cylinder having an inner diameter of 1.0 mm and an average length of 5 mm. 130 ° C. for the shaped catalyst
For 6 hours, then again under air at 500 ° C for 6 hours.
What was heat-treated for a while was used as a catalyst.

The composition of the elements of the obtained catalyst was Mo ₁₂ W _0.3.
Bi _0.6 Fe ₂ Sb _0.7 Ni ₄ Co ₂ Cs _0.45 Mg ₂ S
It was i ₅ . Fill the stainless steel reaction tube with this catalyst,
A raw material mixed gas containing 5% of isobutylene, 12% of oxygen, 10% of steam and 73% (volume%) of nitrogen was passed through the catalyst layer at a contact time of 3.6 seconds and reacted at 360 ° C. as a result,
The reaction rate of isobutylene was 97.2%, the selectivity of methacrolein was 89.4%, and the acid selectivity of methacryl was 3.4%. In addition, the filling powder ratio was 1.4% and the shape change ratio was 7.0%.

Example 8 In Example 7, the outer circumference was elliptical and the longest distance from the center was 3.0 mm, the shortest distance was 1.5 mm, and the inner diameter was 1.0 mm.
Heat treatment and reaction were carried out in the same manner as in Example 7 except that the through hole was formed into a concentric cylinder having an average length of 5.0 mm. As a result, the reaction rate of isobutylene was 97.
The selectivity was 2%, the selectivity of methacrolein was 89.4%, and the selectivity of methacrylic acid was 3.4%. In addition, the filling powder ratio is 1.4
%, And the shape change rate was 7.0%.

Example 9 In Example 7, the outer circumference is elliptical and the longest distance from the center is 3.5 mm, the shortest distance is 1.0 mm, and the inner diameter is 0.5 mm.
Heat treatment and reaction were carried out in the same manner as in Example 7 except that the through hole was formed into a concentric cylinder having an average length of 3.0 mm. As a result, the reaction rate of isobutylene was 97.
The selectivity was 4%, the selectivity of methacrolein was 89.5%, and the selectivity of methacrylic acid was 3.4%. In addition, the filling powder ratio 1.2
%, And the shape change rate was 6.6%.

Example 10 In Example 7, the inner circumference was elliptical, the outer diameter had a radius of 2.5 mm, and the through hole had a maximum distance of 1.0 mm from the center and a minimum distance of 0.5 mm. Heat treatment and reaction were performed in the same manner as in Example 7 except that the shape of the cylinder was concentric with an average length of 5.0 mm. As a result, the reaction rate of isobutylene was 97.3% and the selectivity of methacrolein was 89.4.
%, And the selectivity of methacrylic acid was 3.3%. Further, the filling powdering rate was 1.3% and the shape change rate was 6.8%.

Example 11 In Example 7, the inner circumference was elliptical, the outer diameter had a radius of 2.0 mm, and the through hole had a maximum distance of 1.0 mm from the center and a minimum distance of 0.5 mm. Heat treatment and reaction were performed in the same manner as in Example 7 except that the shape of the cylinder was concentric with an average length of 8.0 mm. As a result, the conversion of isobutylene was 97.1% and the selectivity of methacrolein was 89.2.
%, And the selectivity of methacrylic acid was 3.2%. In addition, the filling powder ratio was 1.9% and the shape change ratio was 7.6%.

Example 12 In Example 7, the inner circumference was elliptical, the outer diameter had a radius of 3.0 mm, and the through hole had a maximum distance of 1.5 mm from the center and a minimum distance of 0.5 mm. Heat treatment and reaction were performed in the same manner as in Example 7 except that the shape of the cylinder was concentric with an average length of 5.0 mm. As a result, the reaction rate of isobutylene was 97.4% and the selectivity of methacrolein was 89.3.
%, And the selectivity of methacrylic acid was 3.5%. In addition, the filling powder ratio was 1.1% and the shape change ratio was 6.1%.

Comparative Example 3 In Example 7, the outer circumference was elliptical, the longest distance from the center was 4.0 mm, the shortest distance was 3.7 mm, and the inner diameter was 2.0 mm.
Heat treatment and reaction were carried out in the same manner as in Example 7 except that the through hole was formed into a concentric cylinder having an average length of 5.0 mm. As a result, the reaction rate of isobutylene was 97.
The selectivity was 0%, methacrolein selectivity was 89.0%, and methacrylic acid selectivity was 3.0%. In addition, the filling powder ratio 6.3
%, And the shape change rate was 14.3%.

Comparative Example 4 The same procedure as in Example 7 was repeated except that the outer peripheral radius was 3.0 mm, the inner peripheral radius was 1.5 mm, and the average length was 5.0 mm. Heat treatment and reaction were performed. As a result, the reaction rate of isobutylene is 96.9%,
The selectivity of methacrolein was 89.0% and the selectivity of methacrylic acid was 2.9%. In addition, the filling powder ratio was 4.2% and the shape change ratio was 11.7%.

Example 13 Using the catalyst of Example 7, the raw material was changed to TBA and the reaction was carried out in the same manner as in Example 7. As a result, TBA
The reaction rate was 100%, the methacrolein selectivity was 87.6%, and the methacrylic acid selectivity was 2.9%.

Example 14 Using the catalyst of Example 10, the raw material was changed to TBA and the reaction was carried out in the same manner as in Example 7. As a result, TB
A reaction rate 100%, methacrolein selectivity 87.7%,
Methacrylic acid selectivity was 2.9%.

Comparative Example 5 Using the catalyst of Comparative Example 4, the raw material was changed to TBA and the reaction was carried out in the same manner as in Example 7. As a result, TBA
The reaction rate was 100%, the methacrolein selectivity was 87.3%, and the methacrylic acid selectivity was 2.3%.

[0044]

The catalyst having the form of the present invention has the effect of improving the yield of the corresponding unsaturated aldehyde and unsaturated carboxylic acid in the gas phase oxidation of propylene, isobutylene, TBA or MTBE.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a catalyst of the present invention.

FIG. 2 is a cross-sectional view of another catalyst of the present invention.

FIG. 3 is a cross-sectional view of a conventional catalyst

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location C07C 47/22 J 7457-4H 57/05 9356-4H // C07B 61/00 300

Claims (2)

[Claims] 1. When producing propylene, isobutylene, tertiary butyl alcohol or methyl tertiary butyl ether by gas phase catalytic oxidation using molecular oxygen to produce the corresponding unsaturated aldehyde and unsaturated carboxylic acid. In the catalyst containing at least molybdenum, bismuth and iron used for the catalyst, the catalyst has a cylindrical shape having a through hole, and its cross section has either an outer circumference or an inner circumference essentially an elliptical shape. However, the other is a circle, the centers of the outer circumference and the inner circumference coincide, and the ratio of the longest distance to the shortest distance on the elliptical shape from the center is 1.2 to 4.0. And a catalyst for synthesizing unsaturated carboxylic acid. 2. A solid catalyst containing at least molybdenum, bismuth and iron, wherein the catalyst shape is a cylindrical shape having a through hole, and the cross section thereof has either an outer circumference or an inner circumference of an essentially elliptical shape. The other is a circle, and the center of the outer circumference and the inner circumference are coincident with each other, and the ratio of the longest distance to the shortest distance of the elliptical shape from the center is 1.2 to 4.0, and propylene, isobutylene, A method for producing a corresponding unsaturated aldehyde and unsaturated carboxylic acid by subjecting tertiary butyl alcohol or methyl tertiary butyl ether to gas-phase catalytic oxidation using molecular oxygen.