RU2801149C2 - Catalyst, method for obtaining catalyst and method for producing unsaturated carboxylic acid and/or unsaturated carboxylic acid ether - Google Patents

Abstract

FIELD: chemical industry.

SUBSTANCE: invention relates to a method for producing an unsaturated carboxylic acid and/or an ester of an unsaturated carboxylic acid by reacting a carboxylic acid and/or an ester of a carboxylic acid with formaldehyde in the presence of a catalyst, wherein the catalyst contains: (i) a compound containing at least one first metallic element selected from boron, magnesium, zirconium and hafnium, and (ii) an alkali metal element, where the compound and the alkali metal element are applied to a carrier containing silanol groups, the average particle size of the compound of the first metal element is 0.4 nm or more and 50 nm or less, the catalyst satisfies the following formula (1):

,

in which X is the molar ratio of the alkali metal element to at least one first metal element in the catalyst, Y is the BET specific surface area of the catalyst (m²/g) and Z is the number of silanol groups per unit area (amount/nm²).

EFFECT: invention provides a process for producing a carboxylic acid and/or an unsaturated carboxylic acid with high selectivity.

8 cl, 1 tbl, 49 ex

Description

Technical field

[0001]

The present invention relates to a catalyst, a method for producing a catalyst, and a method for producing an unsaturated carboxylic acid and/or an ester of an unsaturated carboxylic acid.

State of the art

[0002]

Methyl methacrylate is used in a variety of applications. With regard to methyl methacrylate, a large number of production methods have been studied, such as the ACH method and the direct oxidation method using the starting compound C4, but in recent years, a production method called alpha technology has attracted attention.

In general, alpha technology is a method for producing methyl methacrylate by producing methyl propionate using ethylene as a feedstock, as a pre-stage reaction, and carrying out an aldol condensation reaction of methyl propionate as a post-stage reaction, and various catalysts have been studied, in particular, in order to in order to improve the selectivity and yield of methyl methacrylate in the post-step reaction.

[0003]

For example, Patent Document 1 proposes the use of a catalyst containing a high surface area porous silica containing 1 to 10% by mass of an alkali metal and containing a certain amount of a compound of at least one modifier element selected from boron, magnesium, aluminum , zirconium and hafnium, as a post-stage reaction catalyst in alpha technology.

Prior Art Documents

patent document

[0004]

Patent Document 1:JP2002-511336

The essence of the present invention

Problems to be solved by the present invention

[0005]

In order to obtain methyl methacrylate, which is a target compound, in this industrial process with high productivity, it is desirable to obtain a target product with high selectivity and high yield.

However, it has been found that even when using the catalyst described in Patent Document 1, there is a possibility that the selectivity to methyl methacrylate is insufficient.

Ways to solve problems

[0006]

In view of the above circumstances, the present invention has been made, and the present inventors have found that the above problem can be solved by using a specific catalyst, and they have completed the present invention.

[0007]

That is, the essence of the invention is as follows.

[1] A catalyst comprising:

(i) a compound containing at least one first metallic element selected from boron, magnesium, zirconium and hafnium, and

(ii) the element is an alkali metal,

where the compound and the alkali metal element are applied to a carrier containing silanol groups,

the average particle size of the compound of the first metal element is 0.4 nm or more and 50 nm or less,

the catalyst satisfies the following formula (1):

0.90×10 ^-21 (g/amount) ≦ X/(Y×Z) < 10.8×10 ^-21 (g/amount), formula (1),

in which X is the molar ratio of the alkali metal element to at least one first metal element in the catalyst, Y is the BET specific area of the catalyst surface (m ² /g), and Z is the number of silanol groups per unit area (amount/nm ² ).

[2] The catalyst according to [1], wherein the molar ratio of X of the alkali metal element to the first metal element is 1.3 or more and 6.0 or less.

[3] The catalyst according to [1] or [2], wherein the alkali metal element includes cesium.

[4] The catalyst according to any one of [1] to [3], wherein the first metal element comprises zirconium.

[5] The catalyst according to any one of [1] to [4], which is a catalyst for producing an unsaturated carboxylic acid and/or an unsaturated carboxylic acid ester.

[6] A method for producing an unsaturated carboxylic acid and/or an unsaturated carboxylic acid ester by reacting a carboxylic acid and/or a carboxylic acid ester with formaldehyde in the presence of a catalyst according to any one of [1] to [5].

[7] A method for producing a catalyst containing (i) a compound containing at least one first metal element selected from boron, magnesium, zirconium, and hafnium, and (ii) an alkali metal element, wherein the compound and the element are alkali metal applied to a carrier, the method comprising

impregnating the carrier with a solution or dispersion containing an inorganic salt of the first metallic element to form a first solid residue, and

impregnation of the first solid residue with a solution or dispersion containing an alkali metal salt to obtain a second solid residue.

where the average particle size of the compound of the first metal element is 0.4 nm or more and 50 nm or less, and

the catalyst satisfies the following formula (2):

1.5×10 ^-21 (g/amount) ≦ X'/(Y'×Z') ≦ 17.0×10 ^-21 (g/amount), formula (2),

in which X' is the molar ratio of the alkali metal element to at least one first metal element in the catalyst, Y' is the BET specific surface area of the catalyst (m ² /g), and Z' is the number of silanol groups per unit area (amount/nm ² ).

[8] The method of [7], wherein the solvent of the solution or dispersion containing the inorganic salt of the first metal element contains an alcohol.

[9] The method of [7] or [8], wherein the first metal element is zirconium.

[10] The method according to any one of [7] to [9], wherein the alkali metal element is cesium.

Effect of the present invention

[0008]

According to the present invention, it is possible to provide a catalyst capable of producing an unsaturated carboxylic acid and/or an unsaturated carboxylic acid ester with high selectivity in the reaction of a carboxylic acid and/or a carboxylic acid ester and formaldehyde, and a method for producing the catalyst.

In addition, a process for producing a carboxylic acid and/or an unsaturated carboxylic acid with high selectivity can be provided.

Detailed description of the present invention

[0009]

Further, as an embodiment of the present invention, a method for producing an unsaturated carboxylic acid and/or an ester of an unsaturated carboxylic acid by an aldol condensation reaction of a carboxylic acid and/or a carboxylic acid ester and formaldehyde in the presence of a catalyst will be described.

[0010]

<Catalyst>

The catalyst according to the present embodiment has a configuration in which at least one first metal element selected from boron, magnesium, zirconium and hafnium and an alkali metal element are supported on a support containing silanol groups, and the average particle size of the compound containing the first metal element is 0.4 nm or more and 50 nm or less, and when the molar ratio of the alkali metal element to the first metal element is X, the BET specific surface area (m ² /g) of the catalyst is Y, and the amount of silanol groups per unit area (amount/nm ² ) of the catalyst is Z, the following formula (1) is satisfied.

[0011]

0.90×10 ^-21 (g/amount) ≦ X/(Y×Z) < 10.8×10 ^-21 (g/amount), formula (1)

[0012]

The molar amount of the alkali metal element used in formula (1) shall mean the molar amount of all alkali metal elements contained in the catalyst.

In other words, when 2 or more kinds of alkali metal elements are used, it is assumed to mean the total number of moles of 2 or more kinds of alkali metal elements.

Likewise, the molar amount of the first metal element is also assumed to mean the total number of moles of 2 or more first metal elements when 2 or more first metal elements are used.

[0013]

In addition, in the formula above (1), the molar ratio of the alkali metal element to the first metal element, the amount of silanol groups on the support surface, and the BET specific surface area can be calculated by the method described in the examples described below, respectively.

[0014]

The mechanism by which the above formula (1) can be satisfied to give an unsaturated carboxylic acid and/or an unsaturated carboxylic acid ester with high selectivity in the reaction of a carboxylic acid and/or carboxylic acid esters with formaldehyde is not clear, but when the above formula is satisfied (1) the first metal element and the alkali metal element are moderately highly dispersed on the catalyst surface, and it is believed that the selectivity of the unsaturated carboxylic acid and/or the unsaturated carboxylic acid ester can be improved by high dispersion.

[0015]

The alkali metal element which is the catalyst component is preferably lithium, sodium, potassium, cesium or rubidium, among them, potassium, rubidium or cesium is more preferred, and cesium is particularly preferred. It should be noted that 1 kind of alkali metal elements can be used, or 2 or more kinds can be used.

[0016]

The first metal element is selected from boron, magnesium, zirconium and hafnium as described above, among them, boron or zirconium is preferred, and zirconium is particularly preferred. It should be noted that 1 kind of these metal elements can be used, or 2 or more kinds can be used.

[0017]

In the formula above (1), it is more preferable that the value of X/(Y×Z) is 1.0×10 ^-21 (g/amount) or more to increase the product yield, and it is particularly preferable that it is 1.5× 10 ^-21 (g/amount) or more, while even more preferably it is 10.7×10 ^-21 (g/amount) or less and 10.5×10 ^-21 (g/amount) or less to suppress the decline in product yield.

[0018]

The average particle size of the compound containing the first metal element forming the catalyst is preferably 0.5 nm or more, particularly preferably 0.8 nm or more, while preferably 30 nm or less, more preferably 20 nm or less, more preferably 10 nm or less, even more preferably 8 nm or less, more preferably 6 nm or less, even more preferably 5 nm or less, particularly preferably 4 nm or less, particularly preferably 3 nm or less.

[0019]

Although there is no particular limitation, as long as the above formula (1) is satisfied, the molar ratio of X of the alkali metal element to the first metal element is preferably 1.3 or more, more preferably 1.5 or more, even more preferably 1.7 or more, and especially preferably 1.9 or more, in order to improve the yield of the target product, and, on the other hand, preferably 6.0 or less, more preferably 5.5 or less, and particularly preferably 5.0 or less, in order to suppress reducing the yield of the target product.

[0020]

The proportion of the alkali metal element in the total mass of the catalyst component and the support is not particularly limited, provided that formula (1) above is satisfied, but is preferably 4% by mass or more, more preferably 7% by mass or more, and particularly preferably 9 % by mass or more to increase the yield of the target product, and on the other hand, it is preferably 25% by mass or less, more preferably 18% by mass or less, and particularly preferably 14% by mass or less, to suppress the decrease in yield. target product.

[0021]

The proportion of the first metal element in the total mass of the catalyst component and the support is not particularly limited, as long as the formula (1) above is satisfied, but is preferably 0.3% or more by mass, 0.5% or more by mass, and especially preferably 1.0% or more by mass to increase the yield of the target product, while it is preferably 10% or less by mass, 6% or less by mass, and 5% or less by mass, 4% or less by weight, to reduce the yield of the product.

[0022]

The supported catalyst component may contain a metallic element other than those listed above.

Its examples include aluminum, titanium and iron.

In addition, the ratio of the element to the total weight of the supported catalyst component is preferably 1.0% by mass or less, more preferably 0.5% by mass or less, and particularly preferably 0.2% by mass or less, to suppress the decrease in yield. target product.

[0023]

The supported catalyst component can be composed by including other elements in addition to the above metallic elements.

For example, it can be configured to include an element resulting from the production of a catalyst component.

[0024]

The carrier is capable of supporting the catalyst component, and there is no particular limitation as long as it contains silanol groups on its surface, but in particular, it is preferably a porous carrier based on an inorganic compound containing silica.

[0025]

The support forming material is not particularly limited, and examples thereof include silica, alumina, zeolite, silica containing titanium dioxide, or silica containing zirconia.

Of these, silicon oxide is preferred.

In particular, a commercially available carrier may be used.

Examples include the trade name: CARiACT (manufactured by Fuji Silysia Chemical Co., Ltd.), etc.

[0026]

The number Z of silanol groups per unit area of the catalyst is not particularly limited as long as it satisfies the formula above (1), but it is preferably 0.5 units/Nm ² or more, 0.8 units/Nm ² or more, 2.5 units/nm ² or more, and especially preferably 4 units/nm ² or more to increase the yield of the target product, and on the other hand, it is preferably 20 units/nm ² or less, 17 units/nm ² or less, and 15 units/ nm ² or less, particularly preferably 13 units/nm ² or less to suppress the decrease in the yield of the target compound.

[0027]

Although there is no particular limitation as long as the BET specific surface area Y of the catalyst satisfies the above formula (1), it is preferably 50 m ² /g or more, more preferably 70 m ² /g or more, even more preferably 90 m ² / g or more, particularly preferably 100 m ² /g or more, and preferably 600 m ² /g or less, even more preferably 500 m ² /g or less, particularly preferably 350 m ² /g or less, to increase the yield of the target connections.

[0028]

There is no particular restriction on the form of the carrier, and examples thereof include powdered, granulated, coated or tableted.

[0029]

Although there is no particular limitation on the average particle size of the carrier, it is preferably 500 µm or more, more preferably 1 mm or more, and particularly preferably 1.5 mm or more, in order to suppress pressure loss and suppress generation of by-products during the reaction, and on the other hand, it is preferably 10 mm or less, more preferably 6 mm or less, and particularly preferably 5 mm or less to suppress the generation of by-products.

[0030]

Although there is no particular limitation on the average pore diameter that the carrier has, it is preferably 3 nm or more, more preferably 5 nm or more, and particularly preferably 10 nm or more, in order to suppress the formation of by-products, and on the other hand, it is preferably is 200 nm or less, more preferably 150 nm or less, and particularly preferably 100 nm or less, to ensure the specific surface area.

[0031]

The shape of the catalyst is not particularly limited and may include spherical, columnar, or annular shapes.

It should be noted that the average volume of the catalyst is not particularly limited, but it is preferably 0.06 mm ³ or more and 550 mm ³ or less.

[0032]

The production method of the catalyst is not particularly limited, it can be obtained by depositing a metal element on a carrier.

However, from the point of view of preventing damage to the catalyst, it is preferable to prepare the catalyst by a method including at least the step of impregnating the support with an average particle size of the inorganic salt of the first metal element in a solution or dispersion with a size of 0.4 nm or more and 50 nm or less.

In the present invention, an example is shown below in which the catalyst is obtained by the next first stage to the 4th stage as the preferred form.

[0033]

First step: a step of dissolving or dispersing an inorganic salt of a first metal element in a first solvent to obtain a solution or dispersion.

[0034]

Second step: step of impregnating the carrier with the solution or dispersion obtained by the first step, obtaining a first solid residue.

[0035]

Third step: the step of dissolving or dispersing an alkali metal salt in a second solvent to obtain a solution or dispersion.

[0036]

Fourth step: the step of mixing the first solid residue obtained by the second stage with the solution or dispersion obtained by the third stage to obtain a second solid residue.

[0037]

Each stage is described in detail below.

[0038]

<First stage>

The first metallic element forming an inorganic salt of the first metallic element includes the first metallic element described above.

[0039]

The inorganic salt of the first metal element is an inorganic compound containing no hydrocarbon, and there is no particular limitation, and for example, carbonate, nitrate, sulfate, acetate, ammonium salt, oxide or halide of the first metal element can be used alone or in combination.

For example, when the first metallic element is zirconium, examples thereof include zirconium oxynitrate, zirconium sulfate, zirconium carbonate, zirconium perchlorate, and zirconium acetate.

When the first metal element is boron, examples thereof include boron oxide and the like.

When the first metal element is magnesium, examples thereof include magnesium nitrate, magnesium sulfate, magnesium carbonate, and magnesium acetate.

When the first metallic element is hafnium, examples thereof include hafnium nitrate, hafnium sulfate, hafnium perchlorate, and hafnium acetate.

[0040]

The first solvent is not specifically limited and includes water or an organic solvent.

Among them, alcohol is more preferable as an organic solvent for improving the dispersibility of the inorganic salt of the first metal element.

As the alcohol, an alcohol containing 1 or more and 6 or less carbon atoms is preferred, and methanol is particularly preferred.

[0041]

Although there is no particular limitation on the amount of the inorganic salt of the first metal element relative to 100 ml of solvent, for fixing the first metal element, it is preferably 2 mmol or more, more preferably 5 mmol or more, and particularly preferably 10 mmol or more, and on the other hand, it is preferably 60 mmol or less, more preferably 50 mmol or less, and particularly preferably 40 mmol or less, in order to suppress the applied proportion.

[0042]

In addition, when the inorganic salt of the first metal element is dissolved or dispersed in the first solvent, the first solvent can be stirred.

In addition, it is preferable to leave the resulting solution or dispersion to stand.

There is no particular limitation on the holding time, but if the holding time is long, the average particle size of the inorganic salt of the first metal element in the solution or dispersion tends to be small.

Particularly in the present invention, as will be described below, when the solution or a dispersion is impregnated onto the carrier in the second stage, it is preferred that it has a specific average particle size, and therefore it is preferable to hold it until the desired particle size is obtained.

Specifically, the aging time is preferably 30 minutes or more, more preferably 2 hours or more, even more preferably 4 hours or more, and particularly preferably 16 hours or more.

On the other hand, it is preferably 100 hours or less, more preferably 80 hours or less, and particularly preferably 50 hours or less.

[0043]

<Second stage>

As the carrier, the carrier described above can be used.

[0044]

The method for impregnating the carrier with the first solvent is not particularly limited, and a known method can be used.

For example, there may be a pore-filling method using a first solvent that satisfies the pore volume of the carrier, a soaking method in which the carrier is immersed in the first solvent, and the like.

[0045]

Although there is no particular restriction on the ratio of the carrier to the first solvent, in order to uniformly fix the first metal member, the ratio of the first solvent to the carrier is preferably 0.9 times or more of the pore volume of the carrier, and on the other hand, in order to reduce the amount of solvent used, it is preferable is 10 times or less, particularly preferably 5 times or less, the pore volume of the carrier.

[0046]

The average particle size of the inorganic salt of the first metal element when the carrier is impregnated with the first solvent in which the inorganic salt of the first metal element is dispersed to obtain good catalytic properties as described above is preferably 50 nm or less, even more preferably 30 nm or less, more preferably 20 nm or less, even more preferably 10 nm or less, more preferably 5 nm or less, even more preferably 3 nm or less, particularly preferably 2 nm or less.

On the other hand, even if the average particle size of the inorganic salt of the first metal element is too small, since the change in the selectivity of the target product during the reaction is extremely small, when both the selectivity of the target product and the productivity of the catalyst are considered, the average particle size of the inorganic salt of the first metal element is preferably is 0.4 nm or more, more preferably 0.5 nm or more, and particularly preferably 0.8 nm or more.

The average particle size of the inorganic salt is obtained by measuring a 0.1 mol/l solution of the inorganic salt using laser light at a wavelength of 633 nm by dynamic light scattering, and calculating the volume distribution.

The reason why the selectivity of the target product is improved when the average particle size of the inorganic salt of the first metal element is in the above range is not clear, but it may be that the first metal element has a high dispersibility on the support when the catalyst is produced by this method.

[0047]

Although there is no particular limitation on the impregnation time of the carrier, it is preferable that the impregnation time be 15 minutes or more and 50 hours or less for fixing the first metal member.

[0048]

Upon receipt of the first solid residue, it is preferable to remove the first solvent.

Removal of the first solvent can be carried out in a known manner.

For example, the first solvent can be removed using a rotary evaporator.

In addition, for example, the first solvent can be removed by separating the solid and the first solvent by filtration.

[0049]

In addition, it is preferable to dry and calcinate the obtained first solid residue, but this is not necessary.

Drying or calcination can remove the first solvent remaining in the first solid residue.

These heating temperatures are preferably 50°C or more, more preferably 70°C or more, even more preferably 120°C or more, particularly preferably 400°C or more, while 800°C or less is preferred, more preferably 700° C or less, and particularly preferably 600°C or less.

[0050]

Although there is no particular limitation on the heating time including temperatures higher, especially when the heating temperature is 400°C or more and 800°C or less, it is preferably 15 minutes or more, more preferably 30 minutes or more, particularly preferably 1 hour or more. , and on the other hand, preferably 100 hours or less, particularly preferably 50 hours or less.

[0051]

In the manner described above, the first metal element will be present as a compound, the average particle diameter of the compound containing the first metal element to obtain good catalytic properties is preferably 50 nm or less, even more preferably 30 nm or less, more preferably 20 nm or less, even more preferably 10 nm or less, even more preferably 8 nm or less, more preferably 6 nm or less, even more preferably 5 nm or less, even more preferably 4 nm or less, and particularly preferably 3 nm or less.

On the other hand, even if the average particle size of the compound consisting of the first metal element is too small, since the change in selectivity and yield of the target product during the reaction is extremely small, when both the selectivity of the target product and the productivity of the catalyst are taken into account, the average particle size of the compound consisting of the first metal element is more preferably 0.4 nm or more, even more preferably 0.5 nm or more, and particularly preferably 0.8 nm or more.

The average particle size of the compound consisting of the first metal element can be calculated from an image obtained by observing a plate containing a solid of 300 nm or less using a transmission electron microscope.

It should be noted that although the specific composition of the compound consisting of the first metal element is not clear, consider the inorganic salt of the first metal element, the oxide of the first metal element, the complex oxide of the carrier and the first metal element, and the like.

Although the reason why the deterioration of the catalyst is suppressed due to the fact that the average particle size of the complex inorganic salt composed of the first metal element is in the above range is not clear, it is believed that the first metal element has a high dispersibility on the carrier.

[0052]

Since the BET values of the specific surface area Y and the amount of silanol groups Z of the carrier tend to change during the preparation of the catalyst, in order to obtain a catalyst that improves the selectivity of an unsaturated carboxylic acid and/or an unsaturated carboxylic acid ester in the reaction of a carboxylic acid and/or a carboxylic acid ester and formaldehyde, the molar ratio of the alkali metal element to the first metal element is X', and in the second step, when BET, the specific surface area of the support, when the support is impregnated into the solution or dispersion obtained by the first step, is Y' (m ² /g), and the amount silanol groups per unit area of the carrier is Z' (amount/nm ² ), preferably satisfies the following equation (2).

[0053]

1.5×10 ^-21 (g/amount)≦X'/(Y'×Z')≦17.0×10 ^-21 (g/amount), formula (2)

[0054]

It should be noted that the molar ratio X' of the alkali metal element to the first metal element used at the time of preparation of the catalyst is generally the same as X in the formula above (1).

[0055]

In the formula above (2), the value of X'/(Y'×Z') is more preferably 2.0×10 ⁻²¹ (g/amount) or more, particularly preferably 2.3×10 ⁻²¹ (g/amount) or more to increase the yield of the product, and more preferably 15.0×10 ⁻²¹ (g/amount) or less, and particularly preferably 10.0×10 ⁻²¹ (g/amount) or less to suppress the decrease in the yield of the product.

[0056]

BET specific surface area Y' (m ² /g) of the carrier when the solution or dispersion containing the first metal element is impregnated into the carrier is not particularly limited as long as it satisfies the formula above (1), preferably 50 m ² /g or more, more preferably 60 m ² /g or more, more preferably 70 m ² /g or more, more preferably 90 m ² /g or more, and particularly preferably 100 m ² /g or more, to increase the yield of the target product. On the other hand, it is preferable to have 600 m ² /g or less, more preferably 500 m ² /g or less, and even more preferably 350 m ² /g or less, 300 m ² /g or less is particularly preferred.

[0057]

The amount Z' (amount/nm ² ) of silanol groups per unit surface area of the carrier when the solution or dispersion containing the first metal element is impregnated on the carrier is not particularly limited as long as formula (2) above is satisfied, but it is preferable to have 0. 5 quantity/nm ² or more, more preferably 0.8 quantity/nm ² or more, more preferably 2.5 quantity/nm ² or more, and particularly preferably 4 quantity/nm ² or more, to increase the yield of the target product. On the other hand, it is preferable to have 15 Amount/Nm ² or less, more preferably 13 Amount/Nm ² or less, and 11 Amount/Nm ² or less is particularly preferable, in order to suppress the decrease in product yield.

[0058]

It should be noted that, with the exception of X', Y' and Z', it can be suitably adjusted so as to obtain the desired catalyst.

[0059]

<Third stage>

The alkali metal element includes the alkali metal element described above.

[0060]

The alkali metal salt is not particularly limited, and an alkali metal carbonate, nitrate, sulfate, acetate, ammonium salt, oxide, halide or the like can be used alone or in combination.

For example, when the alkali metal element is cesium, examples thereof include cesium carbonate, cesium bicarbonate, cesium nitrate, and cesium sulfate.

When the alkali metal element is lithium, lithium carbonate, lithium nitrate and the like can be mentioned.

When the alkali metal element is sodium, examples thereof include sodium carbonate, sodium nitrate and sodium sulfate.

When the alkali metal element is potassium, examples thereof include potassium carbonate, potassium nitrate and potassium sulfate.

When the alkali metal element is rubidium, rubidium carbonate, rubidium nitrate, rubidium sulfate and the like can be mentioned.

[0061]

The second solvent is not specifically limited and includes water or organic solvents.

Among them, alcohol is preferable as an organic solvent for improving the dispersibility of the alkali metal salt.

As the alcohol, an alcohol containing 1 or more and 6 or less carbon atoms is preferred, and methanol is particularly preferred.

[0062]

Although there is no particular limitation on the amount of alkali metal salt per 100 ml of solvent, it is preferably 6 mmol or more, more preferably 14 mmol or more, and particularly preferably 25 mmol or more, in order to increase the yield of the product, and on the other hand, it is preferable is not more than 60 mmol, more preferably 50 mmol or less, and particularly preferably 40 mmol or less to suppress the decrease in product yield.

[0063]

In addition, when the alkali metal salt is dissolved or dispersed in the second solvent, the second solvent can be stirred.

In addition, it is preferable that the resulting solution or dispersion is left to stand.

There is no particular limitation on the aging time, but if the aging time is long, the average particle size of the alkali metal salt in the solution or dispersion tends to be small.

Specifically, the holding time is preferably 15 minutes or more, and preferably 50 hours or less.

[0064]

It should be noted that the third step can be carried out before the second step or after the second step.

[0065]

<Fourth Stage>

Although there is no particular restriction on the method of mixing the first solid obtained in the second stage with the solution or dispersion liquid obtained in the third stage, it is preferable to impregnate the first solid obtained in the second stage into the solution or dispersion liquid obtained in the third stage.

[0066]

The method for impregnating the carrier with the second solvent is not particularly limited, and a known method can be used.

For example, there may be a pore-filling method using a second solvent that fills the volume of the cavities of the carrier, or an immersion method in which the carrier is immersed in a second solvent.

[0067]

Although there is no particular limitation on the ratio of the first solid residue to the solution or dispersion, it is preferable that the ratio of the solution or dispersion to the first solid residue is 0.9 times or more of the pore volume of the support for uniformly anchoring the alkali metal, while it is preferably 10 times or less. , particularly preferably 5 times or less than the pore volume of the carrier to reduce the amount of solvent used.

[0068]

Although there is no particular limitation on the impregnation time, it is preferably 15 minutes or more, more preferably 1 hour or more, for the purpose of anchoring the alkali metal, and on the other hand, it is preferably 50 hours or less, and even more preferably 30 hours or less. , in order to increase the productivity of the catalyst.

[0069]

Upon receipt of the second solid residue, it is preferable to remove the second solvent.

Removal of the second solvent can be carried out in a known manner.

For example, a rotary evaporator can be used to remove the second solvent.

In addition, for example, the second solvent can be removed by filtration.

[0070]

In addition, although not necessarily, it is preferable to dry or calcinate the resulting second solid residue.

By drying or calcining, the second solvent remaining in the second solid residue can be removed.

These heating temperatures are preferably 50°C or more, more preferably 70°C or more, even more preferably 120°C or more, particularly preferably 400°C or more, while 800°C or less is preferred, more preferably 700° C or less, and particularly preferably 600°C or less.

Among the above, especially when the heating temperature is 400°C or more and 800°C or less, it is preferably 15 minutes or more, more preferably 30 minutes or more, particularly preferably 1 hour or more, and preferably 100 hours or less, especially preferably 50 hours or less.

The second solid residue thus obtained can be used as a catalyst.

[0071]

The carriers are usually very hygroscopic.

Therefore, it is preferable to calcinate the support to remove moisture before fixing the catalyst component.

In addition, it is preferable to store the previously calcined carrier in an environment in which moisture is removed.

In other words, it is preferable to store the carrier in a desiccator, dry air or dry inert gas, but these methods are not required.

[0072]

The molar ratio of the alkali metal element and the first metal element deposited on the carrier can be controlled by adjusting the amount of the preparation.

[0073]

There are no particular restrictions on the method of controlling the amount of silanol groups per unit surface area of the carrier.

For example, if the content of silica in the carrier is increased, the amount of silanol groups on the surface of the carrier tends to increase, and if the content of silica in the carrier is reduced, the amount of silanol groups on the surface of the carrier tends to decrease.

[0074]

In addition, although there is no particular limitation on the method of adjusting the BET specific surface area of the carrier, if the pore ratio of the carrier is increased, the BET specific surface area of the carrier tends to increase, and if the pore ratio of the carrier is reduced, the BET specific surface area of the carrier tends to decrease.

Therefore, it is only necessary to apply a carrier containing pores so as to obtain the specific surface area required by BET.

[0075]

In other words, when preparing a catalyst that satisfies the formula above (1), each of the molar ratio of the alkali metal element to the first metal element, the number of silanol groups per unit surface area for anchoring, and the specific surface area BET for anchoring should be adjusted as described higher.

[0076]

In the presence of the catalyst prepared according to this embodiment, an unsaturated carboxylic acid and/or an unsaturated carboxylic acid ester can be obtained by reacting a carboxylic acid and/or a carboxylic acid ester with formaldehyde.

In other words, by using a carboxylic acid and/or a carboxylic acid ester as a starting compound, an unsaturated carboxylic acid and/or an unsaturated carboxylic acid ester corresponding to these carboxylic acids and/or carboxylic acid esters can be obtained.

[0077]

The unsaturated carboxylic acid and/or the unsaturated carboxylic acid ester is preferably the unsaturated carboxylic acid and/or the unsaturated carboxylic acid ester represented by the following formula.

[0078]

R ¹ -CH ₂ -COOR ²

[0079]

In the formula above, each R ¹ and R ² independently represents a hydrogen atom or an alkyl group containing 1 or more and 12 or less carbon atoms.

Among them, the catalyst according to the present embodiment is particularly effective in a method for producing methacrylic acid and/or methyl methacrylate by reacting methyl propionate with formaldehyde.

[0080]

The molar ratio of formaldehyde to the total moles of carboxylic acid and carboxylic acid ester used in the reaction of carboxylic acid and/or carboxylic acid ester with formaldehyde is not particularly limited, but it is preferably in the range of 0.05 or more and 20 or less and more preferably in the range of 0.2 or more and 15 or less, to increase the yield of the target product.

[0081]

In addition, it is preferable that the above reaction is further carried out in the presence of an alcohol to suppress the hydrolysis of the ester.

[0082]

In the reaction above, when alcohol is used, the molar ratio of alcohol to the total moles of carboxylic acid and/or carboxylic acid ester is not particularly limited, but is preferably in the range of 0.05 or more and 20 or less, and more preferably in the range of 0.1 or more and 10 or less.

[0083]

In addition, a compound other than the compound above may be contained within a range without significantly impairing the effect of the present invention.

For example, it may contain water.

[0084]

Although there is no particular limitation on the reaction temperature in the reaction above, in order to increase the yield of the target product, it is preferably 100°C or more, more preferably 200°C or more, and particularly preferably 250°C or more, and on the other hand, it is preferably is 400° C. or less, more preferably 370° C. or less, and particularly preferably 360° C. or less, in order to suppress the decrease in the yield of the target product.

[0085]

Although there is no particular limitation on the contact time in the reaction above, it is preferably 0.1 seconds or more, even more preferably 1 second or more, and particularly preferably 2 seconds or more, in order to increase the yield of the target product, and on the other hand, it preferably 100 seconds or less, more preferably 50 seconds or less, and particularly preferably 30 seconds or less, to suppress the formation of by-products.

[0086]

There are no particular restrictions on the production method of the carboxylic acid and/or alkanoic acid ester serving as the starting compound of the reaction above, and they can be produced by a known method.

For example, in the case of methyl propionate, it is preferably produced by an ethylene carbonylation reaction.

In the present invention, the ethylene carbonylation reaction will be described next.

[0087]

The reaction is a method for producing methyl propionate by reacting ethylene with carbon monoxide in the presence of a catalyst.

[0088]

The ratio of ethylene to carbon monoxide is not particularly limited, but is preferably 0.01 mol% or more, more preferably 0.1 mol% or more, and on the other hand, s is preferably 100 mol% or less, and even more preferably 10 mol % or less.

[0089]

The reaction temperature is not particularly limited, but is preferably 20°C or more, more preferably 40°C or more, particularly preferably 70°C or more, while preferably 250°C or less, even more preferably 150°C or less, and particularly preferably 120° C. or less.

[0090]

The reaction time is not particularly limited, but is preferably 0.1 hour or more and 100 hours or less.

[0091]

The catalyst is not particularly limited as long as it is a catalyst for producing an ethylene carbonylation reaction, and a known catalyst can be used.

Examples thereof include a phosphine ligand containing palladium catalyst and the like.

Specific examples of this catalyst include, for example, the catalyst described in JP-A-10-511034.

In addition, this catalyst can be obtained in a known manner.

[0092]

In addition, it is preferable to carry out the above reaction in the presence of an alcohol.

[0093]

There is no particular restriction on the alcohol, and examples thereof include methanol, ethanol, propanol, 2-propanol, 2-butanol or tert-butyl alcohol, and among them, methanol or ethanol is preferred.

It should be noted that 1 kind of alcohol can be used alone, or 2 or more kinds of alcohol can be used in combination.

[0094]

The ratio of ethylene to alcohol is not particularly limited, but is preferably 0.01 mol% or more, more preferably 0.1 mol% or more, and on the other hand, it is preferably 100 mol% or less, and even more preferably 10 mol% or less.

[0095]

Carbon monoxide can be fed in combination with an inert gas to the reaction.

Examples of this inert gas include hydrogen, nitrogen, carbon dioxide and argon.

[0096]

Methyl methacrylate can be obtained by the method described above, but usually, impurities are contained in the obtained methyl methacrylate.

Therefore, in order to remove impurities, it is preferable to purify the resulting methyl methacrylate by a known method such as distillation.

It should be noted that the cleaning conditions can be adjusted, if necessary.

Examples

[0097]

In the present invention, hereinafter, the present invention will be described in detail in examples and comparative examples, but the present invention is not limited to the following examples.

[0098]

In the following examples, the BET specific surface area of the carrier and the catalyst is a value calculated by the BET method at one point using a nitrogen adsorption meter (trade name: Macsorb, manufactured by Mountech Co., Ltd.). The amount of silanol groups (D (Si -OH)) per unit area of carrier and catalyst was calculated from the following formula (3) from the amount of weight loss at 180°C-950°C under conditions of a temperature rise rate of 10°C/min in air flow using a thermogravimetric differential thermal analyzer (manufactured by Rigaku Co., Ltd., model number: TG8120).

[0099]

D(Si-OH) = 2×N _A ×1/18×Δwt/100×1/SA, formula (3)

[0100]

N _A : Avogadro's constant (6.02×10 ²³ (mol ^-1 )

Δwt: % weight loss from 180°C to 950°C

SA: BET specific surface area (m ² /g).

[0101]

In addition, the molar ratio of the alkali metal element to the first metal element was calculated from the content of the first metal element and the alkali metal element measured by X-ray fluorescence analysis.

[0102]

In addition, in some examples, a catalyst wear test was performed.

Specifically, nitrogen was passed through a water-saturated pump heated to 92°C at a flow rate of 20 ml/min, and further passed through a tube heated to 385°C filled with 1 g of catalyst, and the BET specific surface area of the catalyst was measured after 7 days and 28 days of testing, and the reduction rate of BET specific surface area was calculated by the following formula (4).

The examples and comparative examples with the results of the catalyst failure test in Table 1 are the objects on which the catalyst failure tests were carried out.

[0103]

(BET specific surface area of catalyst after 28 days of testing-BET specific surface area of catalyst after 21 days of testing)/(BET specific surface area of catalyst after 7 days of testing)×100, formula (4)

[0104]

<Example 1>

4.5 g of zirconium oxynitrate dihydrate (Kishida Chemical, Special Grade) was dissolved in 135 ml of methanol (Nacalai Tesque, Special Grade) and aged for 24 hours.

60 g of CARiACT Q-10 (trade name, Fuji Silysia Chemical Co., Ltd., particle size 1.7-4 mm, average pore diameter: 10 nm) used as a carrier was immersed in this solution, kept for 3, 5 hours and the solvent was evaporated using a rotary evaporator.

It should be noted that the average particle size of zirconium oxynitrate in methanol when the support was immersed was 0.8 nm.

After that, drying was carried out at 120°C for 14 hours, obtaining the first solid residue.

Of the obtained first solid residue, 30 g was immersed in a solution in which 4.8 g of cesium carbonate (Wako Pure Chemical Industries, Ltd., Class 1) was dissolved in 65 ml of methanol for 3.5 hours, and the second solid residue and solution separated by filtration.

The catalyst was obtained by drying the second solid residue at 120°C for 14 hours.

It should be noted that the particle size of the zirconium catalyst compound was 0.8 nm-5 nm.

[0105]

Then, approximately 3 g of the resulting catalyst was loaded into the reactor.

Thereafter, under normal pressure, a reaction liquid having a molar ratio of methyl propionate, methanol, formaldehyde and water of 1:1.40:0.19:0.5 was passed through an evaporator at 300° C. at a liquid supply rate of 0.034 ml/min, and passed through the reactor at 330°C for 16 hours.

After that, at normal pressure, the reaction liquid with the starting compound having a molar ratio of methyl propionate, methanol, formaldehyde and water of 1:0.64:0.27:0.01 was passed through an evaporator at 300°C and fed into the reactor at 330° C.

The reaction liquid with the starting compound was varied in the feed rate at five points between 0.034 and 0.35 ml/min, and recovered by cooling and condensing the steam at the outlet of the reactor at each feed rate.

The resulting reaction solution was analyzed using gas chromatography (Shimadzu Corporation, trade name: GC-2010) to calculate the yield and selectivity of methacrylic acid and methyl methacrylate at a liquid flow rate of 0.16 ml/min using the following formulas (5) and (6), respectively .

The results obtained are shown in Table 1.

[0106]

(Yield of methacrylic acid and methyl methacrylate)=(molar amount of methacrylic acid and methyl methacrylate produced)/(molar amount of methyl propionate supplied), (formula (5))

[0107]

(Selectivity of methacrylic acid and methyl methacrylate)=(yield of methacrylic acid and methyl methacrylate)/(methyl propionate conversion rate)･･･formula (6)

[0108]

<Examples 2-7>

The selectivity and yield of methacrylic acid and methyl methacrylate were calculated by preparing methacrylic acid and methyl methacrylate in the same manner as in Example 1, except that the catalyst obtained by adjusting the amount of zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing became the values shown in table 1.

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0109]

<Example 8>

The selectivity and yield of methacrylic acid and methyl methacrylate was calculated by preparing methacrylic acid and methyl methacrylate in the same manner as in Example 1, except that the amount of cesium carbonate used was changed to 4.6 g, and the catalyst was prepared by evaporating the solvent using a rotary evaporator instead of using separation second solid residue and liquid by filtration.

It should be noted that the average particle size of zirconium oxynitrate in methanol when the support was immersed was 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0110]

<Examples 9-15>

The selectivity and yield of methacrylic acid and methyl methacrylate were calculated by preparing methacrylic acid and methyl methacrylate in the same manner as in Example 8, except that the catalyst was prepared by adjusting the amount of zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing became the values shown in table 1.

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0111]

<Example 16>

7.3 g of zirconium oxynitrate dihydrate (Kishida Chemical, Special Grade) was dissolved in 57 ml of methanol (Nacalai Tesque, Special Grade) and aged for 24 hours.

This solution was impregnated onto 60 g of CARiACT Q-10 (trade name, Fuji Silysia Chemical Co., Ltd., particle size 1.7-4 mm, average pore diameter: 10 nm) by the pore filling method.

It should be noted that the average particle size of zirconium oxynitrate in methanol, when impregnated onto the support, was 0.8 nm.

After that, drying was carried out at 120°C for 14 hours, obtaining the first solid residue.

From the obtained first solid residue, a solution obtained by dissolving 7.0 g of cesium carbonate in 29 ml of methanol was impregnated using the pore filling method with respect to 30 g.

After that, the catalyst was obtained by drying for 14 hours at 120°C

It should be noted that the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm-5 nm.

After that, methacrylic acid and methyl methacrylate were obtained in the same way as in example 1, calculating the selectivity and yield of methacrylic acid and methyl methacrylate.

The results obtained are shown in Table 1.

[0112]

<Examples 17-21>

Instead of CARiACT Q-10, CARiACT Q15 (trade name, Fuji Silysia Chemical Co., Ltd., particle size: 1.7 mm-4 mm, average pore diameter: 15 nm) was used as a support, and in addition, a catalyst obtained by adjusting the amount of zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing becomes the value shown in Table 1, used as a carrier, and methacrylic acid and methyl methacrylate were obtained in the same manner as in Example 1, calculating the selectivity and yield methacrylic acid and methyl methacrylate.

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0113]

<Examples 22-27>

Instead of CARiACT Q-10, CARiACT Q15C (trade name, Fuji Silysia Chemical Co., Ltd., particle size: 1.7 mm-4 mm, average pore diameter: 15 nm) was used as a carrier, and in addition, a catalyst obtained by adjusting the amount of zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing becomes the value shown in Table 1, was used as a carrier, and methacrylic acid and methyl methacrylate were obtained in the same manner as in Example 1, calculating the selectivity and yield methacrylic acid and methyl methacrylate.

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0114]

<Examples 28-32>

Instead of CARiACT Q-10, CARiACT Q30 (trade name, Fuji Silysia Chemical Co., Ltd., particle size: 1.7 mm-4 mm, average pore diameter: 30 nm) was used as a support, and a catalyst obtained by controlling the amount zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing becomes the value shown in Table 1, was used as a carrier, and methacrylic acid and methyl methacrylate were obtained in the same manner as in Example 1, calculating the selectivity and yield of methacrylic acid and methyl methacrylate .

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0115]

<Examples 33-39>

Instead of CARiACT Q-10, CARiACT Q30C (trade name, Fuji Silysia Chemical Co., Ltd., particle size: 1.7 mm-4 mm, average pore diameter: 30 nm) was used as a support, and a catalyst obtained by controlling the amount zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing becomes the value shown in Table 1 was used as a carrier, and methacrylic acid and methyl methacrylate were obtained in the same manner as in Example 1, calculating the selectivity and yield of methacrylic acid and methyl methacrylate.

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0116]

<Comparative Example 1>

The selectivity and yield of methacrylic acid and methyl methacrylate were calculated by preparing methacrylic acid and methyl methacrylate in the same manner as in Example 1, except that the catalyst obtained by adjusting the amount of zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing became the values shown in table 1.

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0117]

<Comparative Example 2>

The selectivity and yield of methacrylic acid and methyl methacrylate were calculated by preparing methacrylic acid and methyl methacrylate in the same manner as in Example 26, except that the catalyst obtained by adjusting the amounts of zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing became the values shown in table 1.

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0118]

<Comparative Example 3>

The selectivity and yield of methacrylic acid and methyl methacrylate were calculated by preparing methacrylic acid and methyl methacrylate in the same manner as in Example 39, except that the catalyst obtained by adjusting the amount of zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing became the values shown in table 1.

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0119]

<Example 40>

5.4 g of zirconium oxynitrate dihydrate (Kishida Chemical, Special Grade) was dissolved in 125 ml of methanol (Nacalai Tesque, Special Grade) and aged for 24 hours.

This solution was impregnated onto 130 g of CARiACT Q-10 (trade name, Fuji Silysia Chemical Co., Ltd., particle size 1.7-4 mm, average pore diameter: 10 nm) by the pore filling method.

It should be noted that the average particle size of zirconium oxynitrate in methanol upon impregnation onto the support was 0.8 nm.

After that, drying was carried out at 120°C for 14 hours, obtaining the first solid residue.

From the obtained first solid residue, a solution obtained by dissolving 1.9 g of cesium carbonate (Wako Pure Chemical Industries, Grade 1) in 29 ml of methanol was impregnated using the pore filling method with respect to 30 g.

Thereafter, after drying for 14 hours at 120°C, the catalyst was obtained by carrying out calcination for 3 hours at 600°C.

It should be noted that the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm-5 nm.

[0120]

Then, approximately 3 g of the resulting catalyst was loaded into the reactor.

Thereafter, under normal pressure, the reaction liquid having a molar ratio of methyl propionate, methanol, formaldehyde and water of 1:1.40:0.19:0.5 was passed through an evaporator at 300° C. at a flow rate of 0.034 ml/min, and passed through the reactor at 350°C for 16 hours.

After that, at normal pressure, the reaction liquid with the starting compounds, having a molar ratio of methyl propionate, methanol, formaldehyde and water of 1:1.40:0.19:0.5, was passed through an evaporator at 300°C and fed into the reactor at 350° C.

The reaction liquid with the starting compounds was varied in the feed flow rate at five points from 0.35 to 0.034 ml/min, and was recovered by cooling and condensing the steam at the reactor outlet at each feed rate.

The resulting reaction solution was analyzed using gas chromatography (Shimadzu Corporation, trade name: GC-2010) to calculate the yield and selectivity of methacrylic acid and methyl methacrylate at a flow rate of 0.16 ml/min, respectively.

The results obtained are shown in Table 1

[0121]

<Examples 41-42>

The selectivity and yield of methacrylic acid and methyl methacrylate were calculated by preparing methacrylic acid and methyl methacrylate in the same manner as in Example 40, except that the catalyst obtained by adjusting the amount of zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing became the values shown in table 1

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0122]

<Examples 43-45>

Instead of methanol, water was used as a solvent, and in addition, a catalyst obtained by adjusting the amount of zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing became the value shown in Table 1 was used as a carrier, and methacrylic acid and methyl methacrylate was obtained in the same way as in example 40, calculating the selectivity and yield of methacrylic acid and methyl methacrylate.

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 0.8 nm.

In addition, the particle size of the zirconium compound after the preparation of the catalyst was 0.8 nm to 5 nm.

The results obtained are shown in Table 1.

[0123]

<Examples 46-49>

The residence time of zirconium oxynitrate in methanol was changed from 24 hours to 15 minutes, and in addition, the catalyst obtained by adjusting the amount of zirconium oxynitrate dihydrate and cesium carbonate so that the ratio of zirconium and cesium after fixing became the value shown in Table 1 was used as a support , and methacrylic acid and methyl methacrylate were obtained in the same way as in example 42, calculating the selectivity and yield of methacrylic acid and methyl methacrylate.

It should be noted that both average particle sizes of zirconium oxynitrate in methanol when the support was immersed were 10-50 nm.

The results obtained are shown in Table 1.

[0124]

[Table 1]

[0125]

In Table 1, Cs (% by weight) is the proportion of cesium relative to the total weight of the catalyst component and support, Zr (% by weight) is the proportion of zirconium relative to the total mass of the catalyst component and support, and Cs/Zr molar ratio X is the molar the ratio of cesium to zirconium in the catalytic component.

In addition, MMA+MAA yield (%) and MMA+MAA selectivity (%) are the yield selectivity of methyl methacrylate and methacrylic acid, respectively.

[0126]

As can be seen from the results of Table 1, it can be seen that, compared with Comparative Examples 1 to 3, by using a catalyst that does not satisfy the formula (1) above, the selectivity of methacrylic acid and methyl methacrylate is significantly improved by using a catalyst that satisfies the requirements of formula (1) higher.

Claims (24)

1. A method for producing an unsaturated carboxylic acid and/or an ester of an unsaturated carboxylic acid by reacting a carboxylic acid and/or an ester of a carboxylic acid with formaldehyde in the presence of a catalyst, wherein the catalyst contains: (i) a compound containing at least one first metallic element selected from boron, magnesium, zirconium and hafnium, and (ii) the element is an alkali metal, where the compound and the alkali metal element are applied to a carrier containing silanol groups, the average particle size of the compound of the first metal element is 0.4 nm or more and 50 nm or less, the catalyst satisfies the following formula (1): , in which X is the molar ratio of the alkali metal element to at least one first metal element in the catalyst, Y is the BET specific surface area of the catalyst (m ² /g), and Z is the number of silanol groups per unit area (amount /nm ² ). 2. The process for producing an unsaturated carboxylic acid and/or an unsaturated carboxylic acid ester according to claim 1, wherein the molar ratio of X of the alkali metal element to the first metal element is 1.3 or more and 6.0 or less. 3. The method for producing an unsaturated carboxylic acid and/or an ester of an unsaturated carboxylic acid according to claim 1 or 2, where the alkali metal element contains cesium. 4. A method for producing an unsaturated carboxylic acid and/or an ester of an unsaturated carboxylic acid according to any one of paragraphs. 1-3, where the first metal element contains zirconium. 5. A method for producing an unsaturated carboxylic acid and / or an ester of an unsaturated carboxylic acid according to claim 1, where the catalyst contains: (i) a compound containing at least one first metallic element selected from boron, magnesium, zirconium and hafnium, and (ii) an alkali metal element, wherein the compound and the alkali metal element are supported on a carrier, moreover, the catalyst is obtained by a method that includes: impregnating the carrier with a solution or dispersion containing the nitrate of the first metal element to form a first solid residue, and impregnating the first solid residue with a solution or dispersion containing an alkali metal carbonate to obtain a second solid residue, where the average particle size of the compound of the first metal element is 0.4 nm or more and 50 nm or less, and the catalyst satisfies the following formula (2): , in which X' is the molar ratio of the alkali metal element to at least one first metal element in the catalyst, Y' is the BET specific surface area of the catalyst (m ² /g), and Z' is the number of silanol groups per unit area (number/nm ² ). 6. The method for producing an unsaturated carboxylic acid and/or an ester of an unsaturated carboxylic acid according to claim 5, wherein the solvent of the solution or dispersion containing the nitrate of the first metal element contains an alcohol. 7. A process for producing an unsaturated carboxylic acid and/or an unsaturated carboxylic acid ester according to claim 5 or 6, wherein the first metal element is zirconium. 8. A method for producing an unsaturated carboxylic acid and/or an ester of an unsaturated carboxylic acid according to any one of paragraphs. 5-7, where the element - alkali metal is cesium.