JP6727079B2 - Catalyst for producing unsaturated alcohol and method for producing unsaturated alcohol - Google Patents

Description

The present invention relates to a catalyst for producing an unsaturated alcohol by a monomolecular dehydration reaction using a diol compound as a raw material, and a method for producing an unsaturated alcohol using the catalyst.

Allyl type unsaturated alcohols represented by crotyl alcohol are industrially important substances such as being used as intermediates for cosmetics, pharmaceuticals and the like.

In recent years, a method of synthesizing unsaturated alcohol by selective dehydration reaction using cerium oxide as a catalyst for diol has been reported. In this method, an unsaturated alcohol can be directly synthesized by a gas phase reaction (Patent Documents 1 and 2). This method can achieve high conversion and selectivity, but cerium oxide, which is a raw material, is a rare earth and depends on foreign sources, so there is concern about its stable supply and price stability. ..

A method for synthesizing an unsaturated alcohol by a selective dehydration reaction using zirconium oxide as a catalyst has also been reported (Patent Documents 3 and 4). Further, it has been found that the catalyst can be highly activated by supporting an oxide of an alkali metal, an alkaline earth metal or a rare earth metal on the surface of zirconium oxide (Patent Document 5, Non-Patent Document 1, and Non-Patent Document 2). ).

Japanese Patent No. 3800205 Japanese Patent No. 5075192 Japanese Patent No. 4428530 Japanese Patent No. 4424746 Japanese Patent No. 5115368

Journal of Molecular Catalysis A: Chemical, 243, p. 52-59 (2006). Applied Catalysis A: General, Volume 487, p. 226-233 (2014).

INDUSTRIAL APPLICABILITY The present invention selectively produces an unsaturated alcohol catalyst which achieves high conversion and selectivity in a monomolecular dehydration reaction of a diol, and an objective unsaturated alcohol, particularly a specific allylic unsaturated alcohol. The purpose is to provide a method.

As a result of intensive studies, the present inventors have found that a binary or higher mixed metal oxide containing two or more metal elements is a catalyst capable of producing unsaturated alcohols with high efficiency and high selectivity. .. Furthermore, they have found that the intended allyl-type unsaturated alcohol can be highly selectively produced by a monomolecular dehydration reaction by making this catalyst act, and have completed the present invention. In the present specification, the "allylic unsaturated alcohol" refers to an alcohol having a hydroxyl group bonded to a carbon atom bonded to a carbon atom forming a carbon-carbon double bond.

（式中、Ｒ^１〜Ｒ^４はそれぞれ独立に水素原子、炭素数１〜５のアルキル基、又は炭素数６〜１２のアリール基を示す。）

（式中、Ｒ^１〜Ｒ^４は一般式（２）と同一のものを示す。）

（式中、Ｒ^１〜Ｒ^４は一般式（２）と同一のものを示す。）
［１２］
一般式（２）、一般式（３）−１及び一般式（３）−２のＲ^３及びＲ^４が水素原子である［１１］に記載の不飽和アルコールの製造方法。
［１３］
一般式（２）で示される１，３−ジオール型の化合物が１，３−ブタンジオールである［１１］又は［１２］のいずれかに記載の不飽和アルコールの製造方法。
［１４］
一分子脱水反応の反応温度が４００℃以下である［１１］〜［１３］のいずれか一項に記載の不飽和アルコールの製造方法。 That is, the present invention relates to the following [1] to [14].
[1]
General formula (1):
A _2-x B ₂ O _7-σ (1)
(In the formula, A represents a Group 2 or Group 3 metal, B represents a Group 4 or Group 5 metal, and x represents a numerical value in the range of −0.05<x<1.0. , Σ=A metal ion valence×x/2.)
A catalyst for the production of unsaturated alcohols, which is made of a diol compound as a raw material and is composed of a complex metal oxide represented by.
[2]
In the general formula (1), the catalyst for producing unsaturated alcohol according to [1], wherein -0.05<x<0.7.
[3]
In the general formula (1), the catalyst for producing unsaturated alcohol according to [1] or [2], wherein -0.025<x<0.5.
[4]
The catalyst for unsaturated alcohol production according to any one of [1] to [3], wherein the crystal structure of the composite metal oxide represented by the general formula (1) is either a defective fluorite structure or a pyrochlore structure. ..
[5]
The catalyst for producing unsaturated alcohol according to [3], wherein the crystal structure of the composite metal oxide represented by the general formula (1) is a pyrochlore structure.
[6]
The catalyst for unsaturated alcohol production according to [3], wherein the crystal structure of the composite metal oxide represented by the general formula (1) is a defective fluorite type structure.
[7]
In the general formula (1), A is a catalyst for producing an unsaturated alcohol according to any one of [1] to [6], which is at least one selected from the group consisting of rare earth elements.
[8]
In the general formula (1), the catalyst for producing an unsaturated alcohol according to any one of [1] to [7], wherein B is at least one selected from the group consisting of titanium, zirconium, and hafnium.
[9]
In general formula (1), A is yttrium and B is zirconium, The catalyst for unsaturated-alcohol manufacture as described in any one of [1]-[6].
[10]
The catalyst for unsaturated alcohol production according to any one of [1] to [9], which has a BET specific surface area of ² to 80 m ² /g.
[11]
Single-molecule dehydration from a 1,3-diol type compound represented by the general formula (2), characterized by using the catalyst for producing an unsaturated alcohol according to any one of [1] to [10]. A method for producing an unsaturated alcohol represented by the general formula (3)-1 or the general formula (3)-2 by a reaction.

(In formula, R< ¹ >-R< ⁴ > shows a hydrogen atom, a C1-C5 alkyl group, or a C6-C12 aryl group each independently.

^(Wherein, R 1 to R ⁴ represents a general formula identical to (2).)

^(Wherein, R 1 to R ⁴ represents a general formula identical to (2).)
[12]
The method for producing an unsaturated alcohol according to [11], wherein R ³ and R ^{4 in the} general formula (2), the general formula (3)-1 and the general formula (3)-2 are hydrogen atoms.
[13]
The method for producing an unsaturated alcohol according to [11] or [12], wherein the 1,3-diol type compound represented by the general formula (2) is 1,3-butanediol.
[14]
The method for producing an unsaturated alcohol according to any one of [11] to [13], wherein the reaction temperature of the monomolecular dehydration reaction is 400° C. or lower.

According to the present invention, it is possible to provide a catalyst capable of producing an unsaturated alcohol with a high conversion rate and a high selectivity, and to produce a desired allyl-type unsaturated alcohol from a corresponding raw material with high efficiency.

It is a figure which shows the X-ray-diffraction pattern of the catalyst used in Examples 1-3 and Comparative Examples 1-3. It is an enlarged view of the X-ray-diffraction pattern of the catalyst used in Examples 1-3 and Comparative Examples 1-3.

<Catalyst>
Hereinafter, the catalyst for producing unsaturated alcohol of the present invention will be described.
The unsaturated alcohol production catalyst of the present invention has the following general formula (1):
A _2-x B ₂ O _7-σ (1)
(In the formula, A represents a Group 2 or Group 3 metal, B represents a Group 4 or Group 5 metal, and x represents a numerical value in the range of −0.05<x<1.0. , Σ=A metal ion valence×x/2.)
Is a complex metal oxide of binary or more containing two or more kinds of metal elements. By adjusting the composition ratio of the A metal and the B metal, good catalyst performance can be achieved both in yield and selectivity.

By adjusting the composition ratio of the A metal and the B metal, the acidity or basicity of the surface can be arbitrarily changed, so that the catalyst can function as a catalyst for unsaturated alcohol production.

The composition ratio of the A metal and the B metal is adjusted so that x is in the range of −0.05<x<1.0 in the general formula (1): A _2−x B ₂ O _7−σ , The range of 0.05<x<0.7 is preferable, and the range of −0.025<x<0.5 is more preferable. It is considered that the acidity and basicity derived from the A metal and the B metal can be set to appropriate values by setting x in the range of −0.05<x<1.0. Although σ indicates the amount of oxygen defects, it is not easy to experimentally measure the absolute amount thereof. This is because there are some variations in the measured values due to variations in the valence of the metal, metal defects, oxygen defects, and the like.

The composition ratio of A metal and B metal can be determined by elemental analysis such as fluorescent X-ray, SEM-EDX, and ICP.

The crystal structure of the composite metal oxide represented by the general formula (1) is preferably either a defective fluorite type structure or a pyrochlore structure. The pyrochlore structure can be regarded as a face-centered cubic lattice fluorite structure lacking anions. A metal ion has 8 coordination, B metal ion has 6 coordination, and A metal ion has B metal ion. It has a crystallographic feature that it has a larger ionic radius. The defective fluorite type structure shows an intermediate structure between the pyrochlore structure and the fluorite type structure, and is considered to be different only in the amount ratio of metal and oxygen. Although the effect of the crystal structure is not clear, the following mechanism is described in a non-patent document (ACS Catalysis, 3 volumes, p. 721-734 (2013)). That is, the arrangement of metals around oxygen defects, which is found in cerium oxide having a cubic crystal structure, can contribute as active points. It is presumed that many active sites exist in the pyrochlore structure and the defective fluorite structure. From the viewpoint of the amount of oxygen defects, the pyrochlore structure is more preferable.

The pyrochlore structure and the defective fluorite type structure can be determined from the X-ray diffraction patterns, but it is difficult to distinguish them because these two diffraction patterns are almost the same pattern. In general, the crystal structure can be determined by comparing with PDF (Powder Diffraction Database). For example, in La ₂ Zr ₂ O ₇ , when distinguishing a pyrochlore structure from a defective fluorite structure, diffraction peaks attributed to the (331) and (511) planes are slightly different between 2θ=35 and 50°. However, if it exists, it can be confirmed that it has a pyrochlore structure. However, in Y ₂ Zr ₂ O ₇ , since the atomic scattering factors of Y and Zr are about the same, it is not clear whether or not there are diffraction peaks that can be used for distinguishing the crystal structures, and only from the X-ray diffraction pattern. Cannot be uniquely judged. Therefore, in the present disclosure, if the value of Y/Zr is 0.9 or more and 1.05 or less and the position of the main peak of X-ray diffraction is 29.7±0.2°, the structure is a pyrochlore structure, and If the value of /Zr is 0.5 or more and less than 0.9 and the position of the main peak of X-ray diffraction is 29.7±0.2°, it is considered to be a defective fluorite type structure.

The metal A in the general formula (1) is a group 2 or group 3 metal. Preferably, it is one or more selected from the group consisting of magnesium, calcium, strontium, barium, and rare earth elements. As the rare earth element, scandium, yttrium, lanthanum, cerium, neodymium, praseodymium, gadolinium, samarium, and ytterbium are preferable. From the viewpoint of low basicity, the more preferable A metal is at least one selected from the group consisting of rare earth elements. Yttrium is most preferable in consideration of industrial use.

The valence of metal A is 2 for Group 2 elements and 3 for Group 3 elements. That is, the valence of magnesium, calcium, strontium, and barium is 2, and the valence of scandium, yttrium, lanthanum, cerium, neodymium, praseodymium, gadolinium, samarium, and ytterbium is 3.

The B metal in the general formula (1) is a Group 4 or Group 5 metal. It is preferably at least one selected from the group consisting of niobium, tantalum, titanium, zirconium, and hafnium, and more preferably at least one selected from the group consisting of titanium, zirconium, and hafnium. From the viewpoint of weak acidity, the more preferable B metal is at least one selected from the group consisting of titanium and zirconium. Zirconium is most preferred because of the stability of the metal ions.

In the X-ray diffraction pattern, the amount of A metal and the amount of B metal may be slightly confirmed in the form of unreacted simple oxide, but the amount may be about 1/100 in the main peak intensity ratio of X-ray diffraction. For example, the effect on the chemical composition ratio can be ignored, and the catalytic reaction can proceed without any problems.

Preferably the BET specific surface area of the catalyst is in the range of 2~80m ² / g, more preferably 3 to 50 m ² / g, and particularly preferably 5 to 30 m ² / g. When the BET specific surface area is 2 m ² /g or more, contact with the substrate can be increased and activity can be improved. When it is 80 m ² /g or less, reaction active points are formed due to crystallization of particles, so that the reaction selectivity can be enhanced.

<Catalyst production method>
The following general formula (1):
A _2-x B ₂ O _7-σ (1)
(In the formula, A represents a Group 2 or Group 3 metal, B represents a Group 4 or Group 5 metal, and x represents a numerical value in the range of −0.05<x<1.0. , Σ=A metal ion valence×x/2.)
In order to obtain a binary or more complex metal oxide catalyst containing two or more kinds of metal elements shown in, solid phase method, mechanical alloying method, coprecipitation method, sol-gel method, homogeneous precipitation method, hydrothermal synthesis Method, complex polymerization method and the like. Among them, it is preferable to use the industrially producible solid phase method, coprecipitation method, sol-gel method, or hydrothermal synthesis method. In order to obtain a catalyst having a high specific surface area, it is more preferable to use a solid phase method that can be synthesized at low temperature or a hydrothermal synthesis method.

In one example of the hydrothermal synthesis method, an aqueous solution of a metal A salt and a metal B salt is prepared, and an alkaline compound (such as ammonia) is added to adjust the pH to 9.2 or higher. From this, each metal ion co-precipitates and becomes an amorphous mixed sol. This sol is placed in an autoclave container having an inner tube made of Teflon (registered trademark) and subjected to hydrothermal synthesis at 180° C. for 48 hours to obtain a solid catalyst precursor having a defective fluorite-type or pyrochlore-type crystal structure. This is crushed and baked in an air atmosphere at 900 to 1300° C. for 1 to 10 hours. The pre-calcination catalyst may be in the form of powder or pellets. A metal salt and B metal salt by the operation, almost all since it is considered to be recovered, by the molar ratio of the feed of the raw materials, the general formula (1): X a _{A 2-x B 2 O 7} -σ And σ are controlled.

In one example of the coprecipitation method, an aqueous solution of a metal salt of A is added to a sol solution of a hydroxide of metal B, and the solution is added dropwise to an aqueous solution of an alkaline compound (such as ammonia). As a result, the A metal ions are carried on the surface of the B metal hydroxide to form an amorphous mixed sol. This sol is solid-liquid separated and dried to obtain a catalyst precursor. This is crushed and baked in an air atmosphere at 900 to 1300° C. for 1 to 10 hours. The pre-calcination catalyst may be in the form of powder or pellets. It is considered that almost all of the A metal salt and the B metal hydroxide are recovered by the above-mentioned operation. Therefore, depending on the molar ratio of the raw material charged, the compound represented by the general formula (1): A _2-x B ₂ O _7- controls the X and sigma of _sigma.

When an alkaline earth metal such as magnesium, calcium, strontium or barium is used as the metal A, any of basic, neutral and acidic salts may be used. Specifically, magnesium oxide, magnesium chloride, magnesium nitrate, magnesium sulfate, calcium carbonate, calcium chloride, calcium nitrate, calcium sulfate, strontium carbonate, strontium chloride, strontium nitrate, strontium sulfate, barium carbonate, barium chloride, barium nitrate, Examples include barium sulfate.

When a rare earth element containing yttrium, scandium or the like is used as the A metal, any of a basic salt, a neutral salt and an acidic salt may be used. Specific examples thereof include lanthanum oxide, lanthanum hydroxide, lanthanum chloride, lanthanum nitrate, yttrium nitrate, and ytterbium nitrate.

When niobium, tantalum, titanium, zirconium, hafnium, or the like is used as the B metal, any of a basic salt, a neutral salt, and an acidic salt may be used. Specifically, niobium oxide, niobium chloride, pentaethoxyniobium, tantalum oxide, tantalum chloride, pentaethoxytantalum, titanium oxide, titanium chloride, titanium oxalate, titanium isopropoxide, zirconium oxide, zirconium hydroxide, zirconium oxychloride. , Zirconium oxynitrate and the like.

When a coprecipitation method or a hydrothermal synthesis method is performed using the above water-soluble salts of metal A and metal B, a sodium hydroxide aqueous solution, a potassium hydroxide aqueous solution, a calcium hydroxide aqueous solution is used as a pH adjuster or a mineralizer. A basic aqueous solution such as lime water, sodium carbonate aqueous solution, ammonia aqueous solution, triethylamine aqueous solution, pyridine aqueous solution, ethylenediamine aqueous solution, and sodium hydrogen carbonate aqueous solution can be used. Considering the removability of impurities that cause a decrease in catalyst activity, it is preferable to use an aqueous ammonia solution or an aqueous triethylamine solution.

In the hydrothermal synthesis method, a sol solution containing an insoluble amorphous hydroxide salt can be obtained by adjusting the pH of an aqueous solution of a metal A salt and a metal B salt with alkali to 9.0 to 10.5. .. The concentration of each metal salt is preferably 0.01 to 0.5 mol/L. The obtained sol solution is hydrothermally treated in an autoclave. The ratio of the volume of the sol solution to the inner amount of the container is preferably 30 to 80%. The hydrothermal treatment temperature is preferably 120 to 230° C., and the treatment time is preferably 3 to 60 hours. Such hydrothermal synthesis conditions, including cation and anion defect, it is possible to obtain a catalyst precursor (low crystalline _{A 2-x B 2 O 7} -σ).

In the coprecipitation method, a solution obtained by adding an aqueous solution of A metal salt to a sol solution of B metal hydroxide is added dropwise to an aqueous solution of an alkaline compound (ammonia etc.) to finally obtain a mixed solution having a pH of 9.2 or more. .. As a result, an amorphous hydroxide mixture (A(OH) ₃ /B(OH)) in which the A metal ions are carried on the surface of the B metal hydroxide and the A metal ions and the B metal ion species are intermixed _The catalyst precursor can be obtained in the form of ₄ ·nH ₂ O). The concentration of each metal salt is preferably 0.01 to 0.5 mol/L. The temperature of the solution when mixing the solutions is preferably 10 to 100° C., and the stirring time is preferably 5 to 600 minutes. The dropping rate is preferably 0.1 to 100 g/min.

The obtained catalyst precursor is calcined. Crystallization proceeds and the crystallinity is improved by firing, and a pyrochlore type or defective fluorite type crystal structure can be generated.

The firing of the catalyst precursor is preferably performed at a temperature of 600° C. or higher in order to improve the crystallinity. The upper limit temperature is not particularly limited, but if it exceeds 1400°C, the catalyst surface area may not be maintained, and therefore, it is preferably 1300°C or less. A particularly preferable firing temperature is in the range of 700 to 1200°C, and more preferably 900 to 1100°C.

The firing time is preferably 1 to 30 hours in terms of crystal growth, and more preferably 3 to 10 hours.

There is no restriction on the atmosphere during firing, but it is particularly preferable to carry out in an air atmosphere.

Pre-baking may be performed before baking. The calcination is performed in order to improve the handling property during catalyst molding. The calcination condition is preferably performed at a temperature of 120° C. or higher. The upper limit temperature is not particularly limited, but if it exceeds 800°C, the strength of the catalyst molded body may decrease, so 700°C or less is preferable. Particularly preferable calcination temperature is in the range of 200 to 600°C, and more preferably 300 to 500°C. The firing time is preferably 1 to 30 hours in terms of eliminating unevenness in firing, and more preferably 3 to 10 hours.

The shape of the catalyst of the present invention may be independent particles, or the particles may be solidified into pellets. From the viewpoint of handling such as filling the reactor, pellets are preferable. The catalyst may be supported on a carrier inert to the reaction of the present invention. Examples of the carrier include silica, alumina, titania, zirconia, silica-alumina, zeolite, activated carbon and graphite, but are not particularly limited.

<Production of unsaturated alcohol-dehydration reaction of diol>
In the method for producing an unsaturated alcohol of the present invention, the general formula (1): A reference to binary or more complex oxide catalyst comprising two or more metal elements represented by _{2-x B 2 O 7-} σ Then, a monomolecular dehydration reaction from the 1,3-diol type compound is performed.

The 1,3-diol type compound is represented by the general formula (2), and produces an allyl type unsaturated alcohol represented by the general formula (3)-1 and the general formula (3)-2 by a monomolecular dehydration reaction. ..

In the general formulas (2), (3)-1, and (3)-2, R ^{1 to} R ⁴ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an aryl group having 6 to 12 carbon atoms. Indicates a group.

Examples of the alkyl group having 1 to 5 carbon atoms include linear or branched alkyl groups such as methyl group, ethyl group, propyl group and isopropyl group. Examples of the aryl group having 6 to 12 carbon atoms include phenyl group, tolyl group, mesityl group and naphthyl group. Of these, R ^{1 to} R ⁴ are preferably each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, from the viewpoint of selectivity to the dehydration reaction. It is more preferable that R ³ and R ⁴ are hydrogen atoms because steric hindrance around the reaction site of the monomolecular dehydration reaction is small and reactivity is high, and it is most preferable that all of R ^{1 to} R ⁴ are hydrogen atoms. ..

When all of R ^{1 to} R ⁴ are hydrogen atoms, the compound of general formula (2) is 1,3-butanediol and the compound of general formula (3)-1 is crotyl alcohol (2-butene-1). -Ol), the compound of the general formula (3)-2 becomes 3-buten-2-ol.

The reaction formula of the monomolecular dehydration reaction according to the present invention is shown in the following formula (4).

The reactor used in the monomolecular dehydration reaction of the present invention is preferably a continuous gas phase flow reactor. The catalyst may be either of a fixed bed type and a fluidized bed type, and the fixed bed type is particularly preferable from the viewpoint of maintainability.

As an example of the reaction apparatus, a straight tube type reactor having a vaporizer of diol as a reaction raw material on its upper part can be mentioned. A reactor is filled with a catalyst, and a raw material diol produced by vaporizing a raw material diol in a vaporizer is introduced into the reactor. The reaction product is cooled in a heat exchanger at the bottom of the reactor, and the target unsaturated alcohol and unreacted raw materials are recovered. In order to control the raw material concentration and suppress side reactions, the vaporized raw material diol may be diluted with an inert gas such as nitrogen gas or water vapor and then used for the reaction.

The reaction temperature of the monomolecular dehydration reaction is suitably in the range of 250°C or higher and 400°C or lower. If the temperature is 250°C or higher, the reaction proceeds rapidly. On the other hand, when the temperature is 400° C. or less, the influence of the decrease in selectivity due to side reaction becomes small. A more preferable temperature range is 300 to 350°C.

In a straight tube type reactor, the amount of diol introduced per catalyst filling volume can be in the range of 0.1 to 20 kg/(h·L-cat), preferably 0.2 to 15 kg/(h·L). -Cat), and most preferably 0.5 to 10 kg/(hL-cat). When the introduction amount is 0.1 kg/(h·L-cat) or more, a sufficient production amount can be obtained. When the amount introduced is 20 kg/(h·L-cat) or less, unreacted raw materials do not increase, labor for separation and purification is small, and side reactions from the raw materials can be suppressed.

By subjecting the reaction product to an operation such as distillation, the target product can be separated from unreacted raw materials and by-products. The unreacted raw material can be easily reused after being separated from the target product. Therefore, in order to obtain unsaturated alcohol from diol with high efficiency, it is effective to suppress the production of by-products, and it is industrially expected that the selectivity is high even if the conversion rate of the raw material is slightly low. It is advantageous.

Space velocity relative to the catalyst filling volume of feedstream containing diol starting material [SV] may be in the range of 100~40000h ^-1, especially 500～10000H ^-1 are preferred. When the space velocity is 100 h ⁻¹ or more, the contact time does not excessively increase, so that the production of by-products from the 1,3-diol raw material and the produced unsaturated alcohol can be suppressed. When the space velocity is 40,000 h ⁻¹ or less, the conversion rate does not decrease and the amount of unreacted raw material decreases, so that it is not necessary to separate the unreacted raw material at an excessive cost.

The method described above is one of the embodiments of the present invention, but it is possible to take other forms in the implementation.

Hereinafter, the effects of the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples.

[Measurement of chemical composition ratio of catalyst]
For the element content, ZSX Primus II manufactured by Rigaku Corporation was used, and the content was measured by an EZ scan program. The molar ratio of A metal atom to B metal atom was calculated from the following formula.

[X-ray diffraction measurement]
The catalyst was subjected to X-ray diffraction (XRD) measurement using MultiFlex manufactured by Rigaku Corporation. The measurement was performed in continuous scanning mode. The measurement conditions were a tube voltage of 40 kV, a tube current of 40 mA, a sampling width of 0.02°, and a scan speed of 3°/min.

[BET specific surface area]
The BET specific surface area was measured using TriStar 3000 manufactured by Shimadzu Corporation. As a pretreatment, 0.3 g of the catalyst was evacuated at 150° C. for 3 hours and then measured.

[Gas chromatography]
Almost all the product gas after the dehydration reaction was condensed at 5° C. to be liquefied and analyzed by gas chromatography to calculate the reaction conversion rate and the selectivity. As an analysis device, GC-17A manufactured by Shimadzu Corporation, to which a capillary column manufactured by GL Sciences Co., Ltd.: TC-1 (60 m, 0.25 mmφ) was connected, was used. Helium was used as the carrier gas, and detection was performed with an FID detector. The quantification was performed by the internal standard method. After correction of the calibration curve, the yield of the target substance and the remaining amount of the raw material were obtained, and the conversion and selectivity were obtained from these.

The following formulas were used to calculate the conversion rate and selectivity.

(Example 1)
An aqueous solution prepared by adding 200 mL of distilled water to 36.477 g of yttrium nitrate n-hydrate (Wako Pure Chemical Industries, Ltd., purity 99.9%), and 32.225 g of zirconium oxychloride (Kanto Chemical Co., Inc., 99% purity) The aqueous solution prepared by adding 200 mL of distilled water to the above) was mixed, and concentrated ammonia water (Kanto Chemical Co., Inc., purity 28 to 30%) was added dropwise with stirring to adjust the pH to 9.2. The obtained sol solution was put into an SUS autoclave equipped with a Teflon (registered trademark) inner cylinder tube, and subjected to hydrothermal treatment at 180° C. for 48 hours. Powder is collected from the suspension after the treatment with a filter, washed with ion-exchanged water, filtered, dried at 120°C for one day and then allowed to cool to room temperature, and then with an agate mortar. Crushed. The Y ₂ Zr ₂ O ₇ composite oxide of the present invention is obtained by shaping the crushed powder into pellets, sizing the powder to a particle size of 1.4 to 2.8 mm, and then firing the powder in an air atmosphere at 1100° C. for 3 hours. A catalyst (catalyst A) was obtained. The catalyst A had a diffraction peak of 29.7° in FIGS. 1 and 2 and a Y/Zr of 0.9 to 1.05, and was thus found to be a pyrochlore type crystal.

(Example 2)
Except that the 32.829g yttrium nitrate n-hydrate amounts, in the same manner as in Example 1, to obtain a _Y 1.8 _Zr 2 _{O 6.7} composite oxide catalyst of the present invention (Catalyst B). The catalyst B had a diffraction peak of 29.7° in FIGS. 1 and 2 and a Y/Zr of 0.9 to 1.05, and was thus found to be a pyrochlore type crystal.

(Example 3)
A Y _1.6 Zr ₂ O _6.4 composite oxide catalyst (catalyst C) of the present invention was obtained in the same manner as in Example 1 except that the amount of yttrium nitrate n-hydrate was changed to 29.182 g. The catalyst C has a diffraction peak of 29.7° in FIGS. 1 and 2, but has a Y/Zr outside the range of 0.9 to 1.05, and thus is a defective fluorite type crystal. all right.

(Example 4)
Distilled into an aqueous solution prepared by adding 200 mL of distilled water to 30.0937 g of yttrium nitrate n-hydrate (Wako Pure Chemical Industries, Ltd., purity 99.9%), and urea 60 g (Kanto Kagaku Co., Ltd., purity 99% or more). An aqueous solution prepared by adding 200 mL of water was added to 100 g of zirconium hydroxide slurry (Daiichi Rare Element Chemical Industry Co., Ltd., ZSL-10T), heated to 100° C., and stirred for 5 hours. Then, after solid-liquid separation with a suction filter, the obtained cake (solid) was dried at 120° C. for 24 hours, allowed to cool to room temperature, and then crushed with an agate mortar. The crushed powder is molded into pellets, the particle size is adjusted to 1.4 to 2.8 mm, and then the powder is fired in an air atmosphere at 1100° C. for 3 hours to obtain Y _1.94 Zr ₂ O _{6. 91} composite oxide catalyst (catalyst D) was obtained.

(Example 5)
An aqueous solution prepared by adding 200 mL of distilled water to 30.0937 g of yttrium nitrate n-hydrate (Wako Pure Chemical Industries, Ltd., purity 99.9%) was prepared as a zirconium hydroxide slurry (Daiichi Rare Element Chemical Industry Co., Ltd., ZSL- The aqueous solution added to 100 g of 10T) was added dropwise to an aqueous solution of 40 mL of concentrated ammonia water (Kanto Chemical Co., Inc., purity 28 to 30%) added to 360 mL of distilled water, and the mixture was stirred for 1 hour. Then, after solid-liquid separation with a suction filter, the obtained cake (solid) was dried at 120° C. for 24 hours, allowed to cool to room temperature, and then crushed with an agate mortar. The crushed powder is molded into pellets, the particle size is adjusted to 1.4 to 2.8 mm, and then the powder is fired in an air atmosphere at 1100° C. for 3 hours to obtain Y _1.9 Zr ₂ O _{6. 85} composite oxide catalyst (Catalyst E) was obtained.

(Example 6)
36.477 g of yttrium nitrate n-hydrate (Wako Pure Chemical Industries, Ltd., purity 99.9%) was changed to 44.447 g of samarium nitrate hexahydrate (Wako Pure Chemical Industries, Ltd., purity 99.9%). In the same manner as in Example 1, Sm ₂ Zr ₂ O ₇ composite oxide catalyst (catalyst F) of the present invention was obtained.

(Example 7)
43.835 g of yttrium nitrate n-hydrate (Wako Pure Chemical Industries, Ltd., purity 99.9%) was changed to 36.2505 g of neodymium nitrate hexahydrate (Wako Pure Chemical Industries, Ltd., purity 99.9%). In the same manner as in Example 1, the Nd ₂ Zr ₂ O ₇ composite oxide catalyst (catalyst G) of the present invention was obtained.

(Comparative Example 1): Preparation of Y _0.08 Zr ₂ O _4.12 Yttrium nitrate n hydrate (Wako Pure Chemical Industries, Ltd., purity 99.9%) 1.833 g (7.9 mmol) and distilled water 50 mL An aqueous solution prepared by adding 200 mL of distilled water to 80 g of urea (Kanto Chemical Co., Inc., purity: 99% or more) prepared by adding zirconium hydroxide slurry (Daiichi Rare Element Chemical Industry Co., Ltd., ZSL-10T). ) 200 g (zirconium hydroxide amount: 165 mol) was added, and the mixture was heated to 100° C. and stirred for 5 hours. Then, after solid-liquid separation with a suction filter, the obtained cake (solid) was dried at 120° C. for 24 hours, allowed to cool to room temperature, and then crushed with an agate mortar. After pulverizing the pulverized powder temporarily at 500°C, re-pulverizing it in an agate mortar to form pellets, and sizing the pellets to a particle size of 1.4 to 2.8 mm, and then in an air atmosphere at 900°C for 3 hours. It was calcined to obtain the catalyst of Comparative Example 1 (catalyst CA). The catalyst CA was found to be a fluorite type crystal because the diffraction peak of the XRD spectrum was 30.3°.

(Comparative Example 2): Preparation of Ca _0.08 Zr ₂ O _5.08 Comparative example except that 0.4972 g of calcium chloride (Wako Pure Chemical Industries, Ltd., 95%) was used instead of yttrium nitrate n-hydrate. By the same method as in Example 1, a catalyst of Comparative Example 2 (catalyst CB) was obtained. The catalyst CB was found to be a fluorite type crystal because the diffraction peak of the XRD spectrum was 30.2°.

(Comparative Example _{3): Y} 2.1 _{Zr 2} except that the 38.301g prepared yttrium nitrate n-hydrate of _{O 7.15} in a similar manner as in Example 1, Comparative Example 3 (Catalyst CC ) Got. The catalyst CB had a diffraction peak in the XRD spectrum of 29.7° and a Y/Zr of 0.9 to 1.05, and was thus found to be a pyrochlore type crystal.

[Reactor]
For the dehydration reaction of the diol, a fixed-bed atmospheric pressure gas flow reactor was used in all cases. A reaction tube (made of stainless steel) having an inner diameter of 16 mm and a total length of 300 mm was used. A vaporizer for evaporating the raw materials was connected in series to the upper part of the reactor, and a cooler and a gas-liquid separator were installed in the lower part.

[Dehydration reaction of unsaturated alcohol]
4 mL of each catalyst was filled in the atmospheric pressure gas phase flow reactor, and 1,3-butanediol (Kishida Chemical Co., Ltd., special grade) as a raw material 1,3-diol was gasified at 230° C. to obtain 25.8 mL/h. (Examples 1 to 3 and Comparative Examples 1 to 3) or 51.6 mL/h (Examples 4 to 7) were supplied. The dehydration reaction was carried out at about 320 to 340°C (described in Table 1). The space velocity [SV] was 1600 h ^-1 (Examples 1 to 4, 6 and 7, and Comparative Examples 1 to 3) or 3100 h ^-1 (Example 5).

Physical properties and reaction results of the catalysts obtained in Examples 1 to 7 and Comparative Examples 1 to 3 (conversion rate of 1,3-butanediol as a reaction raw material and allyl-type unsaturated alcohol as a reaction product) Table 1 shows the crotyl alcohol (including geometrical isomers) and 3-buten-2-ol that are the same as the above, and the selectivity of 3-buten-1-ol that is the homoallylic alcohol.

As shown in Table 1, it is understood that the composite metal oxide catalyst of the present invention can convert 1,3-diol to the target allylic unsaturated alcohol compound at low temperature and high selectivity. The apparent yield (conversion rate×selectivity) of the catalysts F and G is low because the conversion rate is low, but the higher selectivity is industrially preferable and more advantageous than the comparative example. That is, if the conversion is low but the selectivity is high, the production system contains a large amount of unreacted raw materials and the target product, and the by-products are small. The unreacted raw material can be recycled and reused as a reaction raw material by a separation operation such as distillation. On the other hand, by-products have to be discarded after separation, which increases manufacturing costs.

In Comparative Examples 1 and 2 which are catalysts in which ZrO ₂ is doped with a small amount of Y or Ca, the conversion rate is low, and the amount of homoallyl 3-buten-1-ol (3B1OL), which is an unintended product, is large. To generate. On the other hand, in the catalyst CC of Comparative Example 3 in which X is −0.05 or less, many other by-products are produced.

Claims (12)

General formula (1):
A _2-x B ₂ O _7-σ (1)
(In the formula, A represents yttrium, samarium, or neodymium , B represents zirconium, and when A is yttrium, x represents a numerical value in the range of −0.05<x<1.0, and σ = valence × x / 2 der of a metal ions is, when a is samarium or neodymium, x is 0, sigma = 0 der Ru.)
A catalyst for the production of unsaturated alcohols, which is made of a diol compound as a raw material and is composed of a complex metal oxide represented by. The catalyst for producing an unsaturated alcohol according to claim 1, wherein in the general formula (1), -0.05<x<0.7. In general formula (1), -0.025<x<0.5, The catalyst for unsaturated alcohol manufacture in any one of Claim 1 or 2. The catalyst for unsaturated alcohol production according to any one of claims 1 to 3, wherein the crystal structure of the composite metal oxide represented by the general formula (1) is either a defective fluorite structure or a pyrochlore structure. .. The catalyst for unsaturated alcohol production according to claim 3, wherein the crystal structure of the composite metal oxide represented by the general formula (1) is a pyrochlore structure. The catalyst for unsaturated alcohol production according to claim 3, wherein the crystal structure of the composite metal oxide represented by the general formula (1) is a defective fluorite structure. In the general formula (1), A is yttrium and B is zirconium, The catalyst for unsaturated alcohol production according to any one of claims 1 to 6. BET specific surface area of 2~80m ² / g according to claim 1-7 unsaturated alcohol production catalyst according to any one of. By a monomolecular dehydration reaction from a 1,3-diol type compound represented by the general formula (2), characterized in that the catalyst for producing an unsaturated alcohol according to any one of claims 1 to 8 is used. , A method for producing an unsaturated alcohol represented by the general formula (3)-1 and the general formula (3)-2.

(In formula, R< ¹ >-R< ⁴ > shows a hydrogen atom, a C1-C5 alkyl group, or a C6-C12 aryl group each independently.

^(Wherein, R 1 to R ⁴ represents a general formula identical to (2).)

^(Wherein, R 1 to R ⁴ represents a general formula identical to (2).) The method for producing an unsaturated alcohol according to claim 9 , wherein R ³ and R ^{4 in the} general formula (2), the general formula (3)-1 and the general formula (3)-2 are hydrogen atoms. Method for producing an unsaturated alcohol according to any one of claims 9 or 10 1,3-diol form of the compound represented by the general formula (2) is 1,3-butanediol. Method for producing an unsaturated alcohol according to any one of claims 9-11 the reaction temperature in the first molecular dehydration reaction is 400 ° C. or less.

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