JP2021069962A - Method for producing catalyst for producing unsaturated aldehyde and/or unsaturated carboxylic acid, and method for producing unsaturated aldehyde and/or unsaturated carboxylic acid using the catalyst - Google Patents

Abstract

To provide a method for producing a catalyst for producing a corresponding unsaturated aldehyde and/or unsaturated carboxylic acid by catalytic gas-phase oxidation of an unsaturated hydrocarbon in an efficient and stable manner, and to provide a method for producing an unsaturated aldehyde and/or an unsaturated carboxylic acid using the catalyst.SOLUTION: The method for producing a catalyst includes a step of continuously supplying a raw material containing an inert carrier and a supported powder to a processing container part 2 while rotating the processing container part of a rolling granulator 1 and supplying a binder liquid to perform carrying treatment. When a substantially circular cross section orthogonal to a rotation axis 3 of the processing container part is used as a projection plane, and the projection plane is divided into two semicircular regions by a straight line in the vertical direction passing through the center point thereof, at least a part of the binder liquid is supplied to a part of a place of the processing container part corresponding to the semicircular region on the downward rotation direction side.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for producing a catalyst for catalytic vapor phase oxidation of an unsaturated hydrocarbon to obtain a corresponding unsaturated aldehyde and / or unsaturated carboxylic acid, and using the obtained catalyst to obtain an unsaturated aldehyde and / or an unsaturated carboxylic acid. / Or a method for producing an unsaturated carboxylic acid.

Conventionally, a method for producing a catalyst used for producing acrolein and / or acrylic acid by catalytic vapor phase oxidation of propylene, and a method for producing a catalyst used for producing methacrolein and / or methacrylic acid by catalytic vapor phase oxidation of isobutylene. As a result, many proposals have been made to support a catalytically active component on an inert carrier.

For example, in Patent Document 1 and Patent Document 2, propylene is obtained by supporting a catalytically active ingredient powder containing a composite metal oxide containing molybdenum as an essential ingredient on an inert carrier using a rolling granulator. It is described that a catalyst for the catalytic gas phase oxidation reaction of or isobutylene is produced. When a supported catalyst is produced by carrying out a supported treatment by such a rolling granulation method, a part of the catalyst active component powder used as a raw material is not supported on the carrier and the inner surface of the processing container of the rolling granulator As a result, there is a problem that the yield of the catalyst is low and the mechanical strength of the catalyst is also low.

For the purpose of solving such a problem, for example, Patent Document 3 proposes a method of cleaning the surface of the processing container after the loading treatment with an inorganic substance such as metal or ceramics. Further, Patent Document 4 proposes a method in which powder or the like of a catalytically active ingredient and a binder are each divided and alternately added while adjusting the addition rate using an auto feeder or the like.

International Publication No. 2013/161703 Pamphlet Japanese Unexamined Patent Publication No. 2012-45516 JP-A-2015-85265 JP-A-2017-124384

However, since the method of Patent Document 3 peels off the catalytically active powder adhering to the inner surface of the processing container after the supporting treatment, the problem itself of adhesion of the catalytically active component powder to the inner surface of the processing container during the supporting treatment itself. Is not resolved. Further, in the method of alternately adding the catalyst-active ingredient powder or the like and the binder as in Patent Document 4, the adhesion of the catalyst-active ingredient powder to the inner surface of the processing container is suppressed to some extent, but there are not a few deposits. It remains as it is. If the carrier treatment is continuously continued with the catalytically active component powder adhering to the inner surface of the treatment container, the adhered catalytically active component powder becomes a nucleus and the amount of the adhering amount further increases over time. As a result, the yield is lowered, and the desired supported catalyst cannot be efficiently obtained. Further, if the deposits of the catalyst active component powder are peeled off in a lump state or fine powder is generated due to physical contact with a carrier or the like during the loading process, the desired loading catalyst is not affected. The desired powder or its lumps may be mixed. When the catalyst thus obtained is used in the catalytic gas phase oxidation reaction, the conversion rate and selectivity may decrease, and in some cases, the reaction may run out of control.

Therefore, an object of the present invention is to prevent the supported powder such as a catalytically active component from adhering to the inner surface of the processing container, and to continuously stabilize the supported processing state, thereby supporting the product with desired quality and performance. An object of the present invention is to provide a production method capable of obtaining a catalyst stably and with a high yield.

When raw materials such as a carrier, a supported powder, and a binder liquid are continuously supplied into a processing container of a rolling granulator to perform a supporting treatment, conventionally, the binder liquid is a carrier, a supported powder, and the supported powder. Alternatively, it has generally been practiced to supply only to the region where the granulated granules roll (flow). However, in this method, as described above, the supported powder that was not supported on the carrier or the granulated material gradually adheres to the inner surface of the processing container over time, which not only reduces the yield but also the processing container. It deteriorates the flow state of the carrier and granules inside, which in turn adversely affects the product quality and catalytic performance. Therefore, as a result of intensive research to solve the above problems, the present inventors have carried out the treatment by intentionally supplying the binder solution to a position where the carrier and the granulated material in a fluid state do not exist. We have found that the above problems can be solved by supporting and recovering the supported powder adhering to the inside of the container on a carrier or a granulated material, and have reached the present invention.

That is, the present invention is as follows.
[1] A method for producing a catalyst for producing unsaturated aldehyde and / or unsaturated carboxylic acid by a catalytic vapor phase oxidation reaction of unsaturated hydrocarbons, while rotating the processing container portion of the rolling granulator. Including a step of continuously supplying a raw material containing an inert carrier and a supported powder to the processing container portion and supplying a binder solution for supporting treatment, the shape of the cross section orthogonal to the rotation axis of the processing container portion is formed. It is substantially circular, and when the cross section is used as a projection surface and the projection surface is divided into two semicircular regions by a straight line in the vertical direction passing through the center point thereof, the processing container portion corresponding to the semicircular region on the rotational downward direction side. A method for producing a catalyst for producing an unsaturated aldehyde and / or an unsaturated carboxylic acid, which comprises supplying at least a part of the binder solution to a part of the portions.
[2] The catalyst according to [1], wherein at least a part of the binder liquid is supplied to a part of the processing container portion corresponding to the semicircular region on the rotation up direction side of the two semicircular regions. Manufacturing method.
[3] The amount of the binder liquid supplied to a part of the semicircular region on the downward rotation direction side is 10 to 70% by mass with respect to the total amount of the binder liquid supplied to the processing container portion. The method for producing a catalyst according to 1] or [2].
[4] The method for producing a catalyst according to any one of [1] to [3], wherein the supported powder contains molybdenum, bismuth and iron as essential components.
[5] A method for producing an unsaturated aldehyde and / or an unsaturated carboxylic acid by catalytic vapor phase oxidation of an unsaturated hydrocarbon, which can be obtained by the production method according to any one of [1] to [4]. A method for producing unsaturated aldehydes and / or unsaturated carboxylic acids using a catalyst.

According to the present invention, a catalyst for producing a corresponding unsaturated aldehyde and / or unsaturated carboxylic acid by catalytic vapor phase oxidation of an unsaturated hydrocarbon is produced stably with high yield and with good reproducibility. It becomes possible to do. In addition, since the progress of adhesion of the supported powder to the inner surface of the processing container of the rolling granulator used in the catalyst supporting processing step is suppressed, the supported processing state can be stably maintained and continued, and by extension, the processing container portion. The frequency of cleaning work can be significantly reduced. Furthermore, since a homogeneous supported catalyst can be obtained, unsaturated aldehydes and / or unsaturated carboxylic acids can be stably produced in high yields by performing a catalytic vapor phase oxidation reaction of unsaturated hydrocarbons using the catalyst. be able to.

It is a side view which shows typically the dish type (pan type) rolling granulator which is an example of the rolling granulator used in this invention. Here, the dotted line represents the rotation axis of the processing container portion, and θ represents the angle of the rotation axis with respect to the horizontal plane, that is, the inclination angle of the processing container portion. It is a perspective view which shows typically the dish type (bread type) processing container part in the dish type rolling granulator of FIG. Here, the arrow indicates the rotation direction of the processing container portion, and the shaded portion indicates the outline of the existence position of the carrier, the supported powder, the granules, etc. during the rotation of the processing container portion. It is a figure which shows typically the cross section orthogonal to the rotation axis of the processing container part, that is, the projection plane of the processing container part in this invention, the semicircular region on the rotation up direction side, and the semicircle region on the rotation down direction side. FIG. 3 is a diagram schematically showing a lower region when the semicircular region in FIG. 3 is further divided by a horizontal straight line passing through the center point of the projection plane.

Hereinafter, the method for producing a catalyst according to the present invention and the method for producing an unsaturated aldehyde and / or an unsaturated carboxylic acid using the catalyst obtained by the method will be described in detail, but the scope of the present invention is bound by these explanations. In addition to the following examples, the present invention can be appropriately modified and implemented without impairing the gist of the present invention.

In the method for producing a catalyst of the present invention, a raw material containing an inert carrier and a supporting powder is continuously supplied to the processing container while rotating the processing container of the rolling granulator, and a binder solution is supplied. When a substantially circular cross section orthogonal to the rotation axis of the processing container is used as a projection surface and the projection surface is divided into two semicircular regions by a straight line in the vertical direction passing through the center point thereof. At least a part of the binder liquid is supplied to a part of the processing container portion corresponding to the semicircular region on the rotation downward direction side.

The carrier used in the loading treatment step of the present invention is not particularly limited as long as it is an inert carrier that can support the supported powder on its surface and does not adversely affect the catalytic activity in the catalytic vapor phase oxidation reaction. .. Therefore, the terms "carrier" and "inactive carrier" are synonymous herein. Examples of such an inert carrier include alumina, silica, silica-alumina, titania, magnesia, steatite, cordierite, silica-magnesia, silicon carbide, silicon nitride, zeolite and the like. The shape is not particularly limited, and known shapes such as spherical, cylindrical, and ring-shaped can be used, but spherical or substantially spherical shapes having an aspect ratio of less than 1.2 are preferable.

The supported powder used in the present invention is a catalytically active ingredient and / or the catalyst that can act as a catalyst for catalytic vapor oxidation of unsaturated hydrocarbons to obtain the corresponding unsaturated aldehyde and / or unsaturated carboxylic acid. The catalyst is not particularly limited as long as it contains a precursor of the active ingredient, and the catalytically active ingredient is preferably a composite oxide containing molybdenum, bismuth and iron as essential ingredients, and is further represented by the following general formula (1). The composite oxide to be used is preferably used. That is, as the supported powder used in the present invention, those containing a catalytically active component containing molybdenum, bismuth and iron as essential components are preferable.
_{Mo 12 Bi a Fe b A c} B d C e D f O x (1)
(Here, Mo is selected from the group consisting of molybdenum, Bi is bismuth, Fe is iron, A is selected from the group consisting of cobalt and nickel, and B is selected from the group consisting of alkali metal, alkaline earth metal and thalium. At least one element, C is at least one element selected from the group consisting of tungsten, silicon, aluminum, zirconium and titanium, D is phosphorus, tellurium, antimony, tin, cerium, lead, niobium, manganese, arsenic, boron At least one element selected from the group consisting of and zinc, O is oxygen, and a, b, c, d, e, f and x are the atoms of Bi, Fe, A, B, C, D and O, respectively. Representing a ratio, 0 <a ≦ 10, 0 <b ≦ 20, 2 ≦ c ≦ 20, 0 ≦ d ≦ 10, 0 ≦ e ≦ 30, 0 ≦ f ≦ 4, and x is the oxidation state of each element. It is a numerical value determined by.)

Specific examples of the raw material of the catalytically active component represented by the general formula (1) include oxides, hydroxides, ammonium salts, nitrates, carbonates, sulfates, and organic acid salts of each component element. Salts, their aqueous solutions, sol, etc., or compounds containing a plurality of elements can be used.

These raw materials are mixed with water, for example, to obtain an aqueous solution or an aqueous slurry (hereinafter, also referred to as “starting raw material mixture”). Next, the obtained mixture of starting materials is dried by various methods such as heating and depressurization to obtain a catalyst active ingredient precursor. As a drying method by heating, for example, a powdery catalytically active component precursor can be obtained using a spray dryer, a drum dryer, or the like, or air, nitrogen, or the like can be obtained using a box-type dryer, a tunnel-type dryer, or the like. It is also possible to obtain a block-shaped or flake-shaped catalytically active component precursor by heating in an air stream such as an inert gas or other nitrogen oxides. Further, a method can also be adopted in which the starting material mixture is once concentrated, evaporated to dryness to obtain a cake-like solid, and the solid is heat-treated as described above. As a drying method under reduced pressure, for example, a block-shaped or powder-shaped catalytically active ingredient precursor can be obtained by using a vacuum dryer. Further, if necessary, the obtained catalytically active ingredient precursor can be preliminarily calcined to obtain a catalytically active ingredient.

The catalytically active component and / or its precursor obtained as described above is subjected to a pulverization step or a classification step as necessary to prepare a powder or powder having an appropriate particle size, and this is used as a supported powder in a supporting treatment step. May be offered to. The supported powder is supported on an inert carrier in a subsequent supporting treatment step to obtain a carrier (hereinafter, also referred to as “supported granules”). The particle size of the supported powder is not particularly limited, but is preferably 500 μm or less in terms of excellent workability and supporting characteristics such as ease of handling, uniformity of the obtained carrier, and good yield.

In the supporting treatment step, a binder liquid is used to improve the supporting state. Specific examples of the binder include organic compounds such as ethylene glycol, glycerin, propionic acid, maleic acid, benzyl alcohol, propyl alcohol, butyl alcohol and phenols, water, nitric acid, ammonium nitrate, ammonium carbonate and the like, or two of them. The above mixture can be mentioned. These binders are rolled granulated during the carrying process as a liquid consisting of a single component, a solution consisting of a mixture of a plurality of types, a mixed liquid or a dispersion liquid (hereinafter, these are collectively referred to as "binder liquid"). It is supplied by spraying or spraying into the processing container of the machine. The binder solution may be sprayed or impregnated in advance on the inert carrier before being subjected to the loading treatment step.

In the supporting treatment step of the present invention, the supported powder is supported on the surface of the carrier by a physical operation called a rolling granulation method. Therefore, even if a chemical bond occurs between the supported powder and the carrier, or at least one of these and the binder, the effect on the supporting effect can be almost ignored. Therefore, any composition can be used as the supported powder in the present invention as long as it has the above composition.

In addition to the above carrier, supported powder and binder liquid, a pore-forming agent may be used for the purpose of forming appropriate pores in the catalyst, and inorganic fibers or the like may be used for the purpose of improving the mechanical strength of the catalyst. You may. The pore forming agent is not particularly limited, and starch, cellulose, urea, polyvinyl alcohol, melamine cyanurate and the like can be used, and the inorganic fiber is not particularly limited, and is glass fiber, ceramic fiber, metal. Fiber, mineral fiber, carbon fiber and the like can be used. The supply method is also not particularly limited as long as it can be uniformly dispersed or contained in the catalytically active component in the supporting treatment step. For example, the supporting powder in which the pore-forming agent is added to the binder solution in advance. Any method can be used, such as mixing the body and the above-mentioned inorganic fiber in a powdery state.

The rolling granulator used in the present invention is an apparatus having a processing container portion and capable of producing a granulated product or a carrier by rolling the raw material mixture charged inside while rotating the processing container portion. If there is no particular limitation, for example, rotation having a substantially circular dish-shaped (pan-shaped) bottom surface (also referred to as a dish or pan) that rotates at an angle and a cylindrical outer peripheral side surface connected to the outer periphery thereof. A dish-type (pan-type) rolling granulator equipped with a container part, a drum-type rolling granulator equipped with a cylindrical rotating drum-type rotating container part arranged at an angle, or vibration or shaking during rotation. Examples include a horizontal vibrating pan-type granulator capable of applying motion, a vibrating stirring granulator, and a locking mixer. Of these, FIG. 1 shows that the structure is simple, the granulated state in the container can be directly confirmed, and a high-quality carrier or granulated product can be obtained with a relatively uniform particle size. It is preferable to use the dish-type (pan-type) rolling granulator shown. The material of the processing container portion of the rolling granulator used in the present invention is not particularly limited, and generally includes stainless steel and iron such as SUS304 and SUS316.

Here, the outline of the rolling granulator 1 will be described with reference to FIG. The processing container portion 2 of the rolling granulator 1 has a substantially circular cross-sectional shape orthogonal to the rotation axis (straight line 3 indicated by the dotted line in FIG. 1) passing through the substantially center point thereof, and usually has a constant inclination angle. It is used with θ. The inclination angle θ is defined as the angle of the rotation axis 3 with respect to the horizontal plane 4 on a plane including the rotation axis 3 and perpendicular to the horizontal plane 4, and 0 ° is defined as 90 ° above the vertical plane. It exceeds 90 ° and is preferably 10 to 70 °, more preferably 20 to 60 °. Here, the maximum permissible amount under the usage conditions of the processing container unit 2 is also referred to as a rolling granulator capacity, and this capacity is the processing when the processing container unit 2 is tilted at a predetermined inclination angle θ. Equal to the maximum volume of water that can be placed in container 2. The capacity of the rolling granulator is set according to the required production amount and the processing capacity of the carrier processing device, so it cannot be specified unconditionally, but on an industrial scale, it is usually several tens of dm ³ to several m ^3. The capacity of is used.

The raw material containing the above-mentioned inert carrier and supported powder is continuously supplied to the processing container portion of the rolling granulator, and the supported powder is sequentially supported on the inert carrier by supplying the binder liquid to the raw material. It becomes a supported granule. As the amount of supported granules increases, the particle size of the supported granules increases, and the friction coefficient with the inner surface of the processing container of the rolling granulator decreases. It gradually moves toward the upper layer while rolling and flowing in a state where objects are mixed. On the other hand, the newly supported powders and inert carriers that are continuously supplied and the supported granules that carry a small amount are included in the above-mentioned mixture that is rolling and flowing because the particle size is small and the friction coefficient is large. Move to the lower layer with. A supported granule having a desired supported amount or a desired particle size depending on the inclination of the processing container, the depth of the processing container, the rotation speed, or a combination thereof is discharged beyond the outer peripheral side surface of the processing container, and is discharged. By recovering the supported granules, a desired supported granulated product can be continuously obtained. That is, "continuously" in the present invention means that it is not a batch type.

In the supporting treatment step of the present invention, the raw material containing the inactive carrier and the supporting powder is continuously supplied to the processing container portion of the rolling granulator, but in the initial stage when the supporting treatment is started, the inactive carrier is used. It is not always necessary to start supplying the supported powder to the processing container at the same time. For example, only a part of the inactive carrier is charged in the processing container of the rolling granulator in advance, and then the supply of the remaining inactive carrier and the supported powder is started, or the supply of the supported powder is started first. After that, the inactive carrier and the supported powder may be continuously supplied in most of the supporting treatment steps, such as starting the supply of the inactive carrier later. Among them, in order to start the supporting treatment more smoothly, a method in which a part of the inert carrier is charged in the treatment container in advance and then the remaining inert carrier and the supported powder are continuously supplied is preferable. In that case, the amount of the inert carrier to be charged in the processing container in advance is preferably 0.1 to 0.9 times the capacity of the rolling granulator.

When the inert carrier and the supported powder are continuously supplied, the ratio of the supplied amounts (the supplied amount of the supported powder: the supplied amount of the inert carrier) is set to 1: 0.3 to 1: 1.5. (Volume standard) is preferable. The supply device for supplying the inert carrier and the supported powder into the processing container is not particularly limited as long as the supply amount can be adjusted, such as a vibration type feeder or a belt type feeder.

In the method for producing a catalyst of the present invention, a substantially circular cross section orthogonal to the rotation axis of the processing container portion is projected as a projection surface during the carrying treatment step in which the processing container portion of the rolling granulator is rotated and the carrying treatment is performed. As a result, when the projection surface is divided into two semicircular regions by a straight line in the vertical direction passing through the center point and projected, the above-mentioned portion of the inner surface of the processing container corresponding to the semicircular region on the rotational downward direction side is described. Supply at least a portion of the binder solution. Hereinafter, this content will be specifically described.

As described above, the processing container portion of the rolling granulator is generally a dish-shaped or drum-shaped container having a substantially circular cross section perpendicular to the rotation axis. As an example, FIG. 2 shows a perspective view of a dish-shaped processing container portion 2 having a substantially circular bottom surface portion 5 and a cylindrical outer peripheral side surface portion 6 connected to the outer peripheral portion thereof. Here, the arrows in FIG. 2 indicate the rotation direction of the processing container unit 2. In this processing container, the carrier, the supported powder, and the supported granules (hereinafter, also collectively referred to as “granulation mixture”) follow the rotation direction of the processing container during rotation, and Due to the centrifugal force of rotation, it moves upward along the peripheral edge portion and the outer peripheral side surface portion 6 of the bottom surface portion 5 in the processing container (“7” in FIG. 2). Although it depends on the rotational speed (or centrifugal force) of the processing container, the granulated mixture 7 that has moved upward usually falls downward by its own weight before reaching the highest point in the vertical direction of the processing container. In rolling granulation, these granulation mixtures 7 roll by repeating such movement in the processing container portion, and are supported or granulated on the carrier in a substantially uniform spherical shape. The rotation speed of the processing container in the present invention is preferably 1 to 45 rpm in the case of a rolling granulator that can be generally used on an industrial scale.

FIG. 3 shows a schematic view when a substantially circular cross section orthogonal to the rotation axis of the processing container portion 2 is viewed as a projection surface 8. When the rolling state of the granulated mixture 7 as described above is projected by dividing the projection surface 8 into two semicircular regions by a straight line in the vertical direction passing through the center point O, the rotation up direction is observed. The granulated mixture 7 repeatedly rolls in the range of the processing container portion corresponding to the side semicircular region 9 (the semicircular region shown in white on the left side in FIG. 3). Therefore, in the loading treatment step, when the treatment container portion is rotating, almost the entire amount of the granulated mixture 7 is present at the location of the region 9 in the treatment container.

Conventionally, in the supporting treatment using a rolling granulator, when the binder liquid is directly applied to the inner surface of the processing container portion, the supported powder in contact with the portion is in an overhumidified state to generate viscous aggregates, which is treated. It has been considered that the binder liquid should not come into direct contact with the inner surface of the processing container because the phenomenon of adhering to the inner surface of the container may occur. Therefore, conventionally, the binder liquid is supplied only to the position where it directly hits the granulated mixture 7 existing in the range of the processing container portion corresponding to the semicircular region 9 on the rotation up direction side. However, even in such a conventional method, it is unavoidable that the supplied binder liquid comes into contact with the supported powder in the granulated mixture to form the agglomerates, so that the adhesion to the processing container is completely eliminated. I wasn't able to do that.

On the other hand, in the present invention, when carrying out the supporting treatment continuously while rotating the processing container portion, a region conventionally considered to avoid direct contact with the binder liquid, that is, the processing container portion. By supplying at least a part of the total amount of the binder liquid used to the portion corresponding to the semicircular region 10 (the semicircular region indicated by the diagonal line on the right side in FIG. 3) on the downward rotation direction side, the supported treatment state, specifically The adhesion of the supported powder to the inner surface of the processing container is improved, and a desired supported granule can be stably and efficiently obtained. Although it is not clear why the method of the present invention produces the above-mentioned peculiar effects that could not be considered by the conventional method, there is no carrier or supported granules, and the supported powder is not present. When the binder solution is supplied to the inner surface of the processing container to which the deposit is attached, the adhering material is moistened by the binder solution, so that the adhesive force of the adhering substance to the inner surface of the processing container is reduced, and the carrier or supported granules are in that state. It is considered that the contact with the granulated container is peeled off from the inner surface of the granulation container and further supported on the surface of the carrier or the supported granulated product.

The portion corresponding to the semicircular region 10 on the rotation downward direction side refers to the portion of the bottom surface portion 5 and / or the outer peripheral side surface portion 6 in the region when the processing container portion 2 is rotating.

Here, on the projection surface 8, the straight line in the vertical direction passing through the center point O corresponds to the diameter of the substantially circular projection surface 8, and the length thereof is the length of the above-mentioned rolling granulator. It is set according to the capacity and cannot be unequivocally specified, but on an industrial scale, a diameter of about 600 mm to 2000 mm is usually used.

The type of supplying the binder liquid is not particularly limited, and it can be dropped, sprayed or sprayed using a known nozzle or the like, but the spray type is characterized in that it can be supplied relatively uniformly over a wide range to some extent. preferable. Further, the binder liquid may be supplied continuously, intermittently, or in any case so as to be constantly supplied in a constant amount, and the supply amount may be appropriately supplied. You may change it.

Of the two semicircular regions, it is preferable to supply at least a part of the binder liquid to a part of the processing container portion 2 corresponding to the semicircular region 9 on the rotation up direction side, and it is preferable to supply at least a part of the binder liquid on the rotation up direction side. It is more preferable that the portion of the processing container portion 2 corresponding to the semicircular region 9 is a portion where a mixture containing at least a carrier and a supported granule, that is, a granulation mixture 7 is present.

As described above, in the method for producing a catalyst of the present invention, any method may be used as long as the binder solution is supplied at least to a position in the processing container in which the carrier and the supported granules are not present. For example, it is more preferable that the binder solution is supplied by the method of the combination of the following (a) and (b), or by the method including the following (c).
(A) Supply to the place where the granulated mixture is present,
(B) Supply to a portion on the inner surface of the processing container where the granulated mixture does not exist.
(C) The granulated mixture is simultaneously supplied to both the location where the granulated mixture is present and the location on the inner surface of the processing container where the granulated mixture is not present.

The rolling granulator is a dish-type rolling granulator, and the portion of the processing container portion 2 corresponding to the semicircular region 10 on the downward rotation direction side is the bottom surface portion (dish portion) of the dish-type rolling granulator. , Bread) 5.

Further, the region for supplying the binder liquid is preferably a region below when the semicircular regions 9 and 10 are further divided by a horizontal straight line passing through the center point O of the projection surface 8. That is, the region 11 shown in FIG. 4 is a region further below the semicircular region 9, and the region 12 is a region further below the semicircular region 10.

Further, the amount of the binder liquid supplied to the region 10 or 12 on the rotation downward direction side is preferably 10 to 70% by mass with respect to the total amount of the binder liquid supplied to the processing container portion. ~ 60% by mass is more preferable, and 30 to 50% by mass is further preferable.

The supported granules obtained in the supported treatment step are dried and / or calcined in the subsequent drying step and / or calcining step, if necessary, to produce the unsaturated aldehyde and / or unsaturated carboxylic acid according to the present invention. A catalyst for use is obtained.

In the above drying step, the supported granules are dried using a commonly used box-type dryer, tunnel-type dryer, or the like, using air, an inert gas such as nitrogen, a nitrogen oxide, or a mixture thereof. It may be heated in an air stream such as gas, and the drying temperature is preferably 80 to 300 ° C., more preferably 130 to 250 ° C., and the drying time is preferably 1 to 20 hours.

Further, in the above firing step, the firing temperature is preferably 350 ° C. to 600 ° C., more preferably 400 ° C. to 550 ° C., further preferably 420 ° C. to 500 ° C., and the firing time is preferably 1 to 20 hours. is there. The atmosphere at the time of firing may be an oxidizing atmosphere in which the catalytically active component is oxidized, but a molecular oxygen-containing gas atmosphere is preferable, and firing is particularly preferable under the flow of a molecular oxygen-containing gas. Air is preferably used as the molecular oxygen-containing gas. Further, firing may be performed after the drying step, and when the catalyst active component previously fired as described above is used in the supporting treatment step, the firing step is not always necessary, and only the drying step may be performed. Good. The firing apparatus used in the firing step is not particularly limited, and a box-type firing furnace, a tunnel-type firing furnace, or the like that is generally used can be used.

If necessary, a sieving step may be provided after the supporting treatment step or after the drying step or the firing step for the purpose of obtaining a catalyst having a uniform particle size. Since the supported powder pulverized by sieving can be recycled, it is preferably performed after the supporting treatment step. The supported granulated product having a desired particle size that has been sieved may be recycled in the supporting treatment step, or may be separately supported so as to have a desired particle size. The sieving device is not particularly limited, and for example, a net sieving, a punching metal, a specific gravity sorter, a roller type sorter, or the like can be used, or two or more devices may be used in combination.

Next, a method for producing an unsaturated aldehyde and / or an unsaturated carboxylic acid of the present invention will be described.

In the method for producing an unsaturated aldehyde and / or an unsaturated carboxylic acid of the present invention, a raw material gas containing an unsaturated hydrocarbon is supplied to a fixed bed reactor and a catalytic vapor phase oxidation reaction is carried out using molecular oxygen. In this case, the catalyst obtained by the above-mentioned production method of the present invention is used. Unsaturated hydrocarbons include, for example, propylene or isobutylene. Acrolein and / or acrylic acid is produced by catalytic vapor oxidation of propylene, and methacrolein and / or methacrylic acid is produced by catalytic vapor oxidation of isobutylene.

The reactor used in the method for producing an unsaturated aldehyde and / or an unsaturated carboxylic acid of the present invention is not particularly limited as long as it is a fixed bed reactor, but in particular, a fixed bed multi-tube having a plurality of reaction tubes. Formula reactors are preferred. The inner diameter of the reaction tube is usually preferably 15 to 50 mm, more preferably 20 to 40 mm, still more preferably 22 to 38 mm.

Each reaction tube of the fixed-bed multi-tube reactor is filled with the catalyst obtained by the production method of the present invention, but it is not always necessary to fill only the catalyst having a single composition, and a conventionally known composition is used. It is also possible to fill the plurality of types of catalysts having each of them so as to form a layer (hereinafter, also referred to as “reaction zone”). For example, a method of filling a plurality of catalysts having different occupied volumes, such as JP-A-4-217732, so that the occupied volumes decrease from the inlet side to the outlet side of the raw material gas, or JP-A-10-168003. A method of filling a plurality of catalysts having different loading rates from the inlet side to the outlet side of the raw material gas so that the loading rates increase, or a part of the catalyst as in JP-A-2005-320315 is inactive. A method of diluting with a substance or the like, or a method of combining these may be adopted. At this time, the number of reaction zones is appropriately determined depending on the reaction conditions and the scale of the reactor, but if the number of reaction zones is too large, problems such as complicated catalyst filling work occur. Is preferably about 2 to 6.

Examples of the raw material gas include 1 to 15% by volume, preferably 4 to 12% by volume of propylene or isobutylene, 0.5 to 25% by volume, preferably 2 to 20% by volume of molecular oxygen, and 0 to 30. It can be a mixed gas composed of% by volume, preferably 0 to 25% by volume of water vapor, and the balance of an inert gas such as nitrogen. The reaction conditions in the present invention are not particularly limited, and any conditions generally used for this type of reaction can be carried out. For example, the above-mentioned raw material gas is placed in a temperature range of 250 to 450 ° C. It may be supplied so as to come into contact with the catalyst at a space velocity of ^{300 to 5,000 hr -1} (standard state) under a pressure of 0.1 to 1.0 MPa. The space velocity is a value represented by the following equation.
Space velocity (SV [hr ^-1 ]) = volumetric flow rate of the raw material gas supplied to the reactor (0 ° C., 1 atmospheric pressure condition) / volume of the catalyst filled in the reactor (however, the catalyst and inertness) If the substance is mixed and filled, the volume of the inert substance is excluded)

The grade of the unsaturated hydrocarbon used as the raw material gas is not particularly limited. For example, when propylene is used as the raw material, polymer grade, chemical grade propylene, or the like can be used. Further, a propylene-containing mixed gas obtained by an oxidative dehydrogenation reaction of propane can also be used, and if necessary, air, oxygen, or the like can be added to the mixed gas for use.

When propylene is used as a raw material, acrolein and / or acrylic acid-containing gas can be obtained as a reaction product by the above-mentioned catalytic vapor phase oxidation reaction. This acrolein-containing gas can be further subjected to a contact vapor phase oxidation reaction by a known method to obtain acrylic acid.

When isobutylene is used as a raw material, methacrolein and / or methacrylic acid-containing gas can be obtained as a reaction product by the above-mentioned catalytic vapor phase oxidation reaction. This methacrolein-containing gas can be further subjected to a catalytic vapor phase oxidation reaction by a known method to obtain methacrylic acid.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited by the following examples as well as the present invention, and appropriate modifications are made to the extent that it can be adapted to the gist of the present invention. It is also possible to carry out, all of which are within the technical scope of the invention. In the following, for convenience, "parts by mass" may be simply referred to as "parts".

<Comparative example 1>
[Catalyst production]
1000 parts of ammonium paramolybdate, 2.4 parts of potassium nitrate and 425 parts of 20% by mass silica sol were dissolved in 3800 parts of distilled water (Liquid A). Further, 50 parts of 60% by mass nitric acid was added to 600 parts of distilled water to dissolve 275 parts of bismuth nitrate, 824 parts of cobalt nitrate, 267 parts of iron nitrate and 288 parts of nickel nitrate (Liquid B). Solution B was added to the prepared solution A, and stirring was continued for 1 hour to obtain a slurry. The obtained slurry was heated and stirred to form a cake-like solid, and the obtained solid was dried at 220 ° C. for 3 hours in an air atmosphere to obtain a dried product. The obtained dried product was pulverized to 500 μm or less to obtain a powder of a catalyst active ingredient precursor.

Using a rolling granulator equipped with a circular pan with a diameter of 1300 mm and a dish-shaped processing container made of stainless steel with an outer peripheral side surface having a height of 500 mm, the inclination angle of the processing container was adjusted to 55 °, and the average particle size was adjusted. A 4.0 mm silica-alumina spherical carrier 0.04 m ³ was charged. Next, while rotating the processing container at a rotation speed of 15 rpm, a 20 mass% ammonium nitrate aqueous solution as a binder liquid was continuously supplied to the region on the upstream side of rotation (region 11 shown in FIG. 4) at a supply amount of ^{0.05 m 3 / h.} Using a belt feeder, the catalyst active ingredient precursor powder was ^{supplied in an amount of 0.51 m 3} / h, and the same carrier as above was supplied in an amount of 0.19 m ^{3 / hr.} It was continuously injected into the same area 11. Under these conditions, the carrier treatment was continuously carried out for 5 hours. The granulated material discharged beyond the outer peripheral side surface of the processing container was treated with a specific gravity sorter, and the supported granulated material on which the catalytically active component precursor powder was supported on the carrier was selected and collected. Next, the supported granules sorted by the specific gravity sorter were sorted by an automatic sieving machine set with the following punching metal to obtain a supported granule having a particle size of 5.0 to 6.0 mm. ..
Upper punching metal: 6.0 mm, round hole, 60 ° plover arrangement Lower punching metal: 5.0 mm, round hole, 60 ° plover arrangement

The obtained supported granules having a desired particle size were calcined at 470 ° C. for 6 hours in an air atmosphere to obtain a catalyst 1. The catalyst active component precursor was adhered to the inner surface of the treatment container after the loading treatment with a maximum thickness of about 2 mm, and the metallic luster of the inner surface of the treatment container could hardly be confirmed.

The loading efficiency of the catalyst 1 was 91% by mass, the sieving yield was 90% by mass, and the production yield was 82% by mass, and the metal element composition excluding oxygen as the catalyst active component was as follows.
Catalyst 1: Mo ₁₂ Bi _1.2 Co _6.0 Ni _2.1 Fe _1.4 Si _3.0 K _0.05

Further, as a result of conducting a catalyst performance test (contact gas phase oxidation reaction test of propylene) of the catalyst 1, the conversion rate of propylene was 95.3 mol%, and the total yield of acrolein and acrylic acid was 90.2 mol%. The above results are summarized in Table 1.

The method for calculating the loading efficiency, the sieving yield, the manufacturing yield, the method for the catalyst performance test, and the method for calculating the conversion rate and the yield will be described below.

[Carrying efficiency]
The loading efficiency was determined by the following procedures (1) to (3).
(1) Calculation of theoretical loading ratio About 10 g of the catalytically active component precursor powder supplied in the loading treatment step was sampled and weighed, and calcined at 470 ° C. for 30 minutes in an air atmosphere, and then the mass of the obtained calcined powder. Was weighed, and the weight loss rate was calculated by the following formula.
Weight loss rate = (mass of sampled catalytically active ingredient precursor powder [g] -mass of calcined powder [g]) / mass of sampled catalytically active ingredient precursor powder [g]

Next, the mass of the catalytically active component precursor powder supplied in the loading treatment step as the catalytically active component (hereinafter, also referred to as “supplied component amount”) was calculated by the following formula. The mass of the supplied powder in the following formula means the mass of the catalytically active component precursor powder supplied in the supporting treatment step, and the supported granules are discharged from the outer peripheral side surface of the processing container during the supporting treatment. It is defined as the mass of the catalytically active component precursor powder supplied between the time when the coating is started and the time when the loading treatment step is completed.
Amount of supplied components [kg] = (1-weight loss rate) x mass of supplied powder [kg]

Next, the theoretical loading ratio when all the supplied supported powders were supported on the carrier was calculated by the following formula. The mass of the supported carrier in the following formula is the carrier supplied between the time when the supported granules began to be discharged from the outer peripheral side surface of the processing container during the supporting treatment and the time when the supporting treatment step was completed. Is defined as the mass of.
Theoretical carrier rate [mass%]
= Supply component amount [kg] / (Supply component amount [kg] + mass of supply carrier [kg]) x 100

(2) Calculation of measured loading rate About 100 g of the supported granules sorted and collected by the specific gravity sorter was sampled and calcined at 470 ° C. for 6 hours in an air atmosphere. After weighing the mass (A) of the sample after firing, the sample is boiled in 400 mL of a 10% sodium hydroxide aqueous solution for 30 minutes to dissolve the catalytically active component supported on the carrier and peel off from the carrier. Removed. The carrier obtained after boiling was washed with 400 mL of distilled water for 30 minutes, and then washed with 100 mL of distilled water three times. After further drying at 200 ° C. for 1 hour, the mass (B) of the dried carrier was measured, and the loading ratio was calculated by the following formula.
Measured loading rate [mass%] = (A [g] -B [g]) / A [g] x 100

(3) Calculation of carrier efficiency From the theoretical carrier rate and the measured carrier rate calculated in (1) and (2) above, the carrier efficiency was calculated by the following formula.
Supporting efficiency [mass%] = measured loading rate [mass%] / theoretical loading rate [mass%] x 100

[Division yield]
The sieving yield refers to the ratio of the supported granulated product after sorting by the automatic sieving machine to the supported granulated product after specific gravity sorting, and was calculated by the following formula.
Sieve yield [mass%] = (mass of supported granulated product after sorting by automatic sieving machine [kg]) / (mass of supported granulated product after specific gravity sorting [kg]) × 100

[Manufacturing yield]
The manufacturing yield was calculated by the following formula.
Manufacturing yield [mass%] = loading efficiency [mass%] x sieve yield [mass%] / 100

[Catalyst performance test]
A reactor consisting of a stainless steel reaction tube having a total length of 3000 mm and an inner diameter of 25 mm and a shell for flowing a heat medium covering the reaction tube is installed in the vertical direction, and the catalyst 1 obtained from the upper part of the reaction tube is dropped to have a layer length of 2500 mm. It was filled so as to be. A mixed gas consisting of 8% by volume of propylene, 14% by volume of oxygen, 6% by volume of water vapor, and the balance of nitrogen ^{was introduced from the lower part of the reaction tube at an air velocity of 2000 hr-1} (standard state), and at a heat medium temperature of 315 ° C. A propylene oxidation reaction was carried out.

[Conversion rate and yield]
The propylene conversion rate in the catalyst performance test and the total yield of acrolein and acrylic acid were calculated by the following formulas.
Propene conversion rate [mol%]
= (Mole number of reacted propylene) / (Mole number of supplied propylene) × 100
Acrolein + acrylic acid yield [mol%]
= (Total number of moles of acrolein produced and acrylic acid produced) / (Number of moles of supplied propylene) x 100

<Example 1>
In Comparative Example 1, the nozzle was set so that the binder liquid could be sprayed on the region on the downward rotation direction side (region 12 shown in FIG. 4), and the supply amount ratio of the binder liquid to the region 11 and the region 12 was 90:10. In addition, the carrying treatment and the sorting treatment by the specific gravity sorter and the automatic sieving machine were carried out in the same manner as in Comparative Example 1 except that the flow rate was adjusted so that the total supply amount of the binder liquid was 0.05 m ^{3 / h.} The obtained supported granulated product was calcined at 470 ° C. for 6 hours in an air atmosphere to obtain a catalyst 2. The loading efficiency of the catalyst 2 was 94% by mass, the sieving yield was 91% by mass, and the manufacturing yield was 86% by mass. Adhesion of the catalytically active component precursor to the inner surface of the treatment container was small, and it was confirmed that the loading efficiency was improved as compared with Comparative Example 1. Table 1 shows the results of the catalyst performance test of the catalyst 2.

<Example 2>
In Example 1, the carrier treatment and sorting by a specific gravity sorter and an automatic sieving machine were performed in the same manner as in Example 1 except that the flow rate was adjusted so that the supply amount ratio of the binder liquid to the regions 11 and 12 was 80:20. Processing was carried out. The obtained supported granulated product was calcined at 470 ° C. for 6 hours in an air atmosphere to obtain a catalyst 3. The supporting efficiency of the catalyst 3 was 95% by mass, the sieving yield was 92% by mass, and the manufacturing yield was 87% by mass. No adhesion of the catalyst component precursor was observed on the inner surface of the treatment container, and the metallic luster on the inner surface of the treatment container could be confirmed. Table 1 shows the results of the catalyst performance test of the catalyst 3.

<Example 3>
In Example 1, the carrier treatment and sorting by a specific gravity sorter and an automatic sieving machine were performed in the same manner as in Example 1 except that the flow rate was adjusted so that the supply amount ratio of the binder liquid to the region 11 and the region 12 was 70:30. Processing was carried out. The obtained supported granulated product was calcined at 470 ° C. for 6 hours in an air atmosphere to obtain a catalyst 4. The loading efficiency of the catalyst 4 was further improved to 99% by mass, the sieving yield was 99% by mass, and the manufacturing yield was 98% by mass. No adhesion of the catalyst component precursor was observed on the inner surface of the treatment container, and the metallic luster on the inner surface of the treatment container could be confirmed. The results of the catalyst performance test of the catalyst 4 are shown in Table 1.

<Example 4>
In Example 1, the carrier treatment and sorting by a specific gravity sorter and an automatic sieving machine were performed in the same manner as in Example 1 except that the flow rate was adjusted so that the supply amount ratio of the binder liquid to the regions 11 and 12 was 50:50. Processing was carried out. The obtained supported granulated product was calcined at 470 ° C. for 6 hours in an air atmosphere to obtain a catalyst 5. The loading efficiency of the catalyst 5 was 99% by mass, the sieving yield was 98% by mass, and the manufacturing yield was 97% by mass. No adhesion of the catalyst component precursor was observed on the inner surface of the treatment container, and the metallic luster on the inner surface of the treatment container could be confirmed. Table 1 shows the results of the catalyst performance test of the catalyst 5.

<Example 5>
In Example 1, the carrier treatment and sorting by a specific gravity sorter and an automatic sieving machine were performed in the same manner as in Example 1 except that the flow rate was adjusted so that the supply amount ratio of the binder liquid to the regions 11 and 12 was 40:60. Processing was carried out. The obtained supported granulated product was calcined at 470 ° C. for 6 hours in an air atmosphere to obtain a catalyst 6. The loading efficiency of the catalyst 6 was 99% by mass, the sieving yield was 90% by mass, and the manufacturing yield was 89% by mass. No adhesion of the catalyst component precursor was observed on the inner surface of the treatment container, and the metallic luster on the inner surface of the treatment container could be confirmed. The results of the catalyst performance test of the catalyst 6 are shown in Table 1.

<Example 6>
In Example 1, the carrier treatment and sorting by a specific gravity sorter and an automatic sieving machine were performed in the same manner as in Example 1 except that the flow rate was adjusted so that the supply amount ratio of the binder liquid to the regions 11 and 12 was 30:70. Processing was carried out. The obtained supported granulated product was calcined at 470 ° C. for 6 hours in an air atmosphere to obtain a catalyst 7. The loading efficiency of the catalyst 7 was 99% by mass, the sieving yield was 89% by mass, and the manufacturing yield was 88% by mass. No adhesion of the catalyst component precursor was observed on the inner surface of the treatment container, and the metallic luster on the inner surface of the treatment container could be confirmed. Table 1 shows the results of the catalyst performance test of the catalyst 7.

<Example 7>
In Example 1, the carrier treatment and the same as in Example 1 except that the binder liquid was not supplied to the region 11 and the binder liquid was supplied only to the region 12 at ^{a supply amount of 0.05 m 3 / h.} Sorting processing was carried out using a specific gravity sorter and an automatic sieving machine. The obtained supported granulated product was calcined at 470 ° C. for 6 hours in an air atmosphere to obtain a catalyst 8. The loading efficiency of the catalyst 8 was 99% by mass, the sieving yield was 89% by mass, and the manufacturing yield was 88% by mass. No adhesion of the catalyst component precursor was observed on the inner surface of the treatment container, and the metallic luster on the inner surface of the treatment container could be confirmed. The results of the catalyst performance test of the catalyst 8 are shown in Table 1.

1 Rolling granulator 2 Processing container 3 Rotating shaft 4 Horizontal surface 5 Bottom (dish, pan)
6 Outer peripheral side surface 7 Granulated mixture 8 Cross section (projection surface) orthogonal to the rotation axis of the processing container
9 Semi-circular area on the up-rotation direction 10 Semi-circle area on the down-rotation side 11 Area below the semi-circle area on the up-rotation side 12 Area below the semi-circle area on the down-rotation direction θ Tilt angle O Center point

Claims (5)

A method for producing a catalyst for producing an unsaturated aldehyde and / or an unsaturated carboxylic acid by a catalytic vapor phase oxidation reaction of an unsaturated hydrocarbon, wherein the processing is performed while rotating the processing container portion of the rolling granulator. A step of continuously supplying a raw material containing an inert carrier and a supported powder to the container portion and supplying a binder solution for the supporting treatment is included, and the shape of the cross section orthogonal to the rotation axis of the processing container portion is substantially circular. When the cross section is used as a projection surface and the projection surface is divided into two semicircular regions by a straight line in the vertical direction passing through the center point thereof, one of the portions of the processing container portion corresponding to the semicircular region on the downward rotation direction side. A method for producing a catalyst for producing an unsaturated aldehyde and / or an unsaturated carboxylic acid, which comprises supplying at least a part of the binder solution to the portion. The method for producing a catalyst according to claim 1, wherein at least a part of the binder liquid is supplied to a part of the processing container portion corresponding to the semicircular region on the rotation up direction side of the two semicircular regions. .. Claim 1 or claim 1, wherein the amount of the binder liquid supplied to a part of the semicircular region on the rotation downward side is 10 to 70% by mass with respect to the total amount of the binder liquid supplied to the processing container portion. 2. The method for producing a catalyst according to 2. The method for producing a catalyst according to any one of claims 1 to 3, wherein the supported powder contains molybdenum, bismuth and iron as essential components. A method for producing an unsaturated aldehyde and / or an unsaturated carboxylic acid by catalytic vapor phase oxidation of an unsaturated hydrocarbon, using a catalyst obtained by the production method according to any one of claims 1 to 4. , A method for producing unsaturated aldehydes and / or unsaturated carboxylic acids.

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