Method for producing modified aluminosilicate and method for producing aromatic dihydroxy compound using modified aluminosilicate

Abstract

To provide a method for producing modified aluminosilicate, modified aluminosilicate, and aromatic dihydroxy compounds using the method, which produces hydroquinones highly selectively by reaction of phenols with hydrogen peroxide under industrially advantageous conditions.SOLUTION: A method for producing a modified aluminosilicate includes: step 1 of producing an aluminosilicate (A1) by a specific method; step 2 of producing an aluminosilicate (A2) by bringing the aluminosilicate (A1) into contact with an acid two or more times; and step 3 of producing a modified aluminosilicate (A3) by bringing the aluminosilicate (A2) into contact with a compound (B) that contains one or more elements selected from the group consisting of Group 4 elements and Group 5 elements of the periodic table and calcining the same. There is also disclosed a method for producing an aromatic dihydroxy compound by reacting phenols with hydrogen peroxide in the presence of the modified aluminosilicate (A3).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a modified aluminosilicate and a method for producing an aromatic dihydroxy compound using the modified aluminosilicate. [Background technology]

[0002] Aromatic dihydroxy compounds are important as intermediates or raw materials for various organic synthesis, and are used in the fields of reducing agents, rubber chemicals, dyes, medicines, agricultural chemicals, polymerization inhibitors, oxidation inhibitors, and the like. Aromatic dihydroxy compounds obtained by reacting phenols with hydrogen peroxide include, for example, hydroquinone and catechol, and the production ratio of hydroquinone and catechol varies depending on the production method. In recent years, in view of the demand balance between hydroquinone and catechol, a method for highly selectively producing hydroquinone in particular is desired.

[0003] A method has been disclosed in which titanosilicate, which is a type of crystalline porous silicate, is used as a catalyst to produce an aromatic dihydroxy compound by reacting a phenol with hydrogen peroxide (e.g., Patent Document 1 and Patent Document 2). Patent Document 3 discloses a titanosilicate obtained by treating an acid-treated aluminosilicate with gas-phase titanium chloride or titanium alkoxide.

[0004] Furthermore, Patent Document 4 discloses a method for producing titanosilicate, in which an aluminosilicate mold raw material, an aluminum source, a titanium source, a silicon source, an iodide, and water are mixed together to prepare a gel, which is heated to crystallize it, and then calcined to produce a titanosilicate.

[0005] The present inventors have disclosed a method for producing a modified aluminosilicate such as an aluminotitanosilicate by contacting an aluminosilicate compound with a liquid titanium halide compound, and that the modified aluminosilicate is suitable as a catalyst for reacting a phenol with hydrogen peroxide to obtain an aromatic dihydroxy compound (Patent Document 5, Patent Document 6).

[0006] On the other hand, the above-mentioned aluminosilicate template raw material (hereinafter sometimes referred to as "structure directing agent") is a relatively expensive material, and since the manufacturing process of the modified aluminosilicate includes a calcination step, recovery and reuse are not possible, and the manufacturing method of the aluminosilicate tends to be high cost. For this reason, manufacturing methods of aluminosilicate that do not use the above-mentioned template raw material have also been reported. (Patent Document 7, Patent Document 8) It is disclosed that the aluminosilicate obtained in these documents can be used as a raw material for exhaust gas decomposition catalysts for automobiles and the like, and for paraffin decomposition catalysts for naphtha and the like. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 4254009 [Patent Document 2] International Publication No. 2015 / 041137 [Patent Document 3] JP 2008-050186 A [Patent Document 4] JP 2017-057126 A [Patent Document 5] International Publication No. 2019 / 225549 [Patent Document 6] International Publication No. 2022 / 225050 [Patent Document 7] International Publication No. 2011 / 013560 [Patent Document 8] JP 2013-237613 A Summary of the Invention [Problem to be solved by the invention]

[0008] The aluminosilicates produced without using the above-mentioned template raw material disclosed in the examples of Patent Documents 7 and 8 have a relatively lower Si / Al molar ratio than the aluminosilicates obtained using the above-mentioned template raw material. Specifically, it is disclosed that the Si / Al molar ratio is 6.4 when the above-mentioned template raw material is not used, and the Si / Al molar ratio is 13.1 when the above-mentioned template raw material is used. In addition, when various catalysts are produced using the above-mentioned aluminosilicate, Patent Document 7 performs an ion exchange process and a steam treatment process. Patent Document 8 performs an acid treatment process in addition to the above two processes. It is disclosed that the ion exchange process is a process for converting alkali metal ions such as sodium into ammonium ions, and the steam treatment process and the acid treatment process are processes for the purpose of desorbing aluminum. As a result, a part of the aluminum is removed from the above-mentioned aluminosilicate, and an aluminosilicate with a high Si / Al ratio is obtained.

[0009] It is obvious that an aluminosilicate produced without using the above-mentioned aluminosilicate template raw material (before ion exchange treatment, etc.) can be produced at a relatively low cost, which is attractive from the viewpoint of commercialization, etc. On the other hand, according to the study by the present inventors, an aluminotitanosilicate prepared using an aluminosilicate obtained without using the above-mentioned aluminosilicate template raw material did not have sufficient performance as a catalyst for reacting phenols with hydrogen peroxide to obtain an aromatic dihydroxy compound.

[0010] Therefore, an object of the present invention is to provide a method for producing a modified aluminosilicate that is suitable as a catalyst for producing an aromatic dihydroxy compound (e.g., hydroquinone) by reacting a phenol with hydrogen peroxide, even if an aluminosilicate that can be obtained without using the above-mentioned template raw material or an aluminosilicate having a low Si / Al molar ratio is used. [Means for solving the problem]

[0011] As a result of investigations into the above-mentioned problems, the present inventors have found that a modified aluminosilicate obtained by subjecting a specific aluminosilicate to a process of treating the aluminosilicate with an acid multiple times can improve the selectivity of hydroquinones when hydroquinones are produced by reacting phenols with hydrogen peroxide, and have thus completed the present invention.

[0012] That is, the present invention includes the following items [1] to [5]. [1] A method for producing a modified aluminosilicate, comprising the following steps 1 to 3: (Process 1) A step of contacting (α) silicon oxide, (β) aluminum oxide, (γ) alkali metal compound, (δ) water, and (ε) aluminosilicate crystals at 100 to 200° C. under conditions that satisfy the following iv) to v) to prepare an aluminosilicate (A1) having a molar ratio of Si / Al of 3 to 12.5: iv) The component (ε) is an aluminosilicate crystal having a Si / Al (molar ratio) of 4 to 15. v) Component (ε) / Component (α): 0.1~20% by weight (Process 2) a step of contacting the aluminosilicate (A1) with an acid two or more times and then calcining the resulting aluminosilicate (A2) (Step 3) a step of contacting the aluminosilicate (A2) with a compound (B) containing one or more elements selected from the group consisting of Group 4 elements and Group 5 elements of the periodic table, and calcining the compound to prepare a modified aluminosilicate (A3); [2] The method for producing a modified aluminosilicate according to [1], wherein the compound (B) is a liquid compound. [3] The method for producing a modified aluminosilicate according to [1] or [2], wherein the aluminosilicate (A1) is contacted with an acid two or more times with different acid concentrations. [4] The method for producing a modified aluminosilicate according to any one of [1] to [3], wherein the step 1 is carried out in the absence of a structure-directing agent. [5] A method for producing an aromatic dihydroxy compound, comprising a step of contacting the modified aluminosilicate (A3) according to [1] with a phenol and hydrogen peroxide. Effect of the Invention

[0013] According to the method for producing a modified aluminosilicate which is one embodiment of the present invention, it is possible to produce a modified aluminosilicate which is suitable as a catalyst for use in producing an aromatic dihydroxy compound (e.g., hydroquinone) by reacting a phenol with hydrogen peroxide. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] A preferred embodiment for carrying out the present invention will be described below. Note that the embodiment described below is an example of a typical embodiment of the present invention, and the scope of the present invention is not to be interpreted narrowly by this embodiment.

[0015] <Method for producing modified aluminosilicate> One embodiment of the present invention is a method for producing a modified aluminosilicate, comprising the following steps 1 to 3. (Process 1) A step of contacting (α) silicon oxide, (β) aluminum oxide, (γ) alkali metal compound, (δ) water (HO), and (ε) aluminosilicate crystals at 100 to 200° C. in a mixture containing the following components iv) to v) to prepare an aluminosilicate (A1) having a molar ratio of Si / Al of 3 to 12.5: iv) The component (ε) is an aluminosilicate crystal having a Si / Al (molar ratio) of 4 to 15. v) Component (ε) / Component (α): 0.1~20% by weight (Process 2) a step of contacting the aluminosilicate (A1) with an acid two or more times and then calcining the resulting aluminosilicate (A2) (Step 3) a step of contacting the aluminosilicate (A2) with a compound (B) containing one or more elements selected from the group consisting of Group 4 elements and Group 5 elements of the periodic table, and calcining the compound to prepare a modified aluminosilicate (A3);

[0016] The lower limit of the Si / Al molar ratio is preferably 4, more preferably 4.5, and even more preferably 5. On the other hand, the lower limit is preferably 12.0, more preferably 11, even more preferably 10, and particularly preferably 9. Each step will be described in detail below.

[0017] (Process 1) More specifically, in step 1, (α) silicon oxide, (β) aluminum oxide, (γ) an alkali metal compound, and (δ) water (HO) are contacted with each other, and further iv) Aluminosilicate crystals with Si / Al (molar ratio): 4 to 15 (ε) aluminosilicate crystals that satisfy v) Component (ε) / Component (α): 0.1~20% by weight and contacting at 100 to 200° C. to prepare an aluminosilicate (A1) having a molar ratio of Si / Al of 3 to 12.5.

[0018] The lower limit of the Si / Al molar ratio is preferably 4, more preferably 4.5, and even more preferably 5. On the other hand, the lower limit is preferably 12.0, more preferably 11, even more preferably 10, and particularly preferably 9. The aluminosilicate (A1) is preferably a beta zeolite or an MSE zeolite.

[0019] The beta zeolite may have characteristics such as (a) an external shape being approximately octahedral, and (b) a Si / Al ratio of 5 or more. In particular, those having both characteristics (a) and (b) are preferable.

[0020] The beta zeolite and MSE zeolite as described above preferably have a Bronsted acid site. From this viewpoint, the zeolite of the present invention is preferably a proton type. However, it may contain a small amount of ammonium ion or alkali metal ion as long as it does not impair the effect of the present invention.

[0021] The beta zeolite and MSE zeolite have an average particle size of preferably 0.2 to 2.0 μm, more preferably 0.5 to 1.0 μm. The BET specific surface area is 400 to 650 m. 2 / g, preferably 500 to 650 m 2 / g, 550-650m 2 / g. Furthermore, the micropore volume is preferably 0.10 to 0.28 cm. 3 / g, and 0.15 to 0.25 cm 3 / g is more preferable. The specific surface area and volume are measured using a BET surface area measuring device.

[0022] A more preferred method of the above step 1 is to prepare a sol-gel sol-gel by mixing (α) silicon oxide, (β) aluminum oxide, (γ) an alkali metal compound, and (δ) water (HO). i) Si / Al: 15 to 200 (molar ratio) ii) Alkali metal / Si: 0.10 to 0.80 (molar ratio) iii) HO / Si: 4.0 to 50 (molar ratio) and iv) Aluminosilicate crystals with Si / Al (molar ratio): 4 to 15 (ε) aluminosilicate crystals that satisfy v) Component (ε) / Component (α): 0.1~20% by weight and contacting the components at 100 to 200° C. to prepare an aluminosilicate (A1).

[0023] More preferred conditions for the above are as follows: i-1) Si / Al: 17-200 (molar ratio) ii-1) Alkali metal / Si: 0.15 to 0.70 (molar ratio) iii-1) H2O / Si: 4.5-30 (molar ratio)

[0024] The Si is mainly derived from (α) silicon oxide, and the Al is mainly derived from (β) aluminum oxide. The alkali metal is mainly derived from (γ) alkali metal compound. (δ) water is used as, for example, pure water. However, the Si, Al, alkali metal, and water may be contained in a plurality of components. For example, as described below, the (α) component may be an aqueous dispersion, gel, or sol of silica, the (β) component may be an alkali metal-containing component or aqueous solution such as sodium aluminate, and the (γ) alkali metal compound may be a water-containing substance or aqueous solution. The above definitions i) to iii) are determined taking into consideration elements and molecules contained across these multiple components.

[0025] The (α) silicon oxide used to obtain a contact product satisfying the above molar ratio includes silica itself and silicon-containing compounds capable of generating silicate ions in water. Specific examples include wet-process silica, dry-process silica, colloidal silica, sodium silicate, and aluminosilicate gel. These silicon oxides can be used alone or in combination of two or more. Among these silicon oxides, the use of silica (silicon dioxide) is preferred because it allows the production of zeolite without producing unnecessary by-products.

[0026] As the (β) aluminum oxide, for example, a water-soluble aluminum-containing compound can be used. Specific examples include sodium aluminate, aluminum nitrate, and aluminum sulfate. Aluminum hydroxide is also a suitable example. These (β) aluminum oxides can be used alone or in combination of two or more. Among these (β) aluminum oxides, the use of sodium aluminate or aluminum hydroxide is preferred in that zeolite can be obtained without producing unnecessary by-products (such as sulfates and nitrates).

[0027] Examples of the (γ) alkali metal compound include hydroxy compounds of alkali metals such as sodium hydroxide and potassium hydroxide. When sodium silicate is used as the (α) silicon oxide or when sodium aluminate is used as the (β) aluminum oxide, the sodium contained therein as an alkali metal component is simultaneously regarded as sodium hydroxide (as described above) and is also regarded as a (γ) alkali metal compound. Therefore, the (γ) alkali metal compound is calculated as the sum of all the alkali metal atoms contained in the reaction system.

[0028] The (δ) water can be any known water without limitation as long as it does not impair the object of the present invention. Specifically, pure water, distilled water, and deionized water can be mentioned, but tap water, industrial water, etc. can also be used as long as it does not impair the object of the present invention. In addition, water that has been brought into contact with various adsorbents to adjust the ratio of the contents can also be used.

[0029] iv) (ε) aluminosilicate crystals having a Si / Al (molar ratio) of 4 to 15 may be considered as aluminotitanosilicates generally called seed crystals. As such (ε) aluminosilicate crystals, any known aluminosilicate crystals may be used without limitation as long as they satisfy the above-mentioned requirement iv).

[0030] Specific examples of the (ε) aluminosilicate crystals of the present invention include so-called beta-type zeolite seed crystals. More specifically, known MCM-type zeolites, YNU-type zeolites, MSE-type zeolites, etc. can be exemplified, and more specifically, MCM-type zeolites such as MCM-68 zeolite and YNU-2 zeolite can be exemplified. The average particle size of such (ε) aluminosilicate crystals is 150 nm or more, preferably 150 to 1000 nm, more preferably 200 to 600 nm. The average particle size can be measured by a known method. For example, it can be determined as the particle diameter of the most frequent crystals in observation with a scanning electron microscope. The (ε) aluminosilicate crystals may be used in a small amount, and may be obtained by using the template raw material. However, the (ε) aluminosilicate crystals are preferably aluminosilicates that do not contain the above-mentioned mold raw materials, which are obtained by decomposing the above-mentioned mold raw materials through a firing step, etc., as described below. It is also possible to use, as the (ε) aluminosilicate crystals, the aluminosilicate (A2) obtained through, for example, step 2 of the present invention, which will be described later.

[0031] The amount of the (ε) aluminosilicate crystal used is in the range of 0.1 to 20% by weight based on the (α) silicon oxide. The lower limit is preferably 0.3% by weight, more preferably 0.5% by weight. On the other hand, the upper limit is preferably 17% by weight, more preferably 15% by weight.

[0032] The components (α) to (ε) are contacted and reacted at 100 to 200°C (in the present invention, the term "contact" may include the meaning of "react"). The temperature is preferably in the range of 120 to 180°C, and heating is performed under autogenous pressure. At temperatures below 100°C, the crystallization rate is extremely slow, and the efficiency of production of the aluminosilicate crystals (A1) may be poor. On the other hand, at temperatures above 200°C, an autoclave with high pressure resistance is required, which is not only uneconomical but also may increase the rate of impurity generation.

[0033] The reaction time within the above temperature range in step 1 is not critical in the present production method, and heating should be continued until aluminosilicate crystals with sufficiently high crystallinity are formed. In general, a reaction time of about 5 to 150 hours is suitable.

[0034] When the components (α) to (ε) are contacted, the order of contacting the components is not particularly limited. Preferably, a method that can easily obtain a uniform reaction mixture is adopted. For example, a uniform reaction mixture can be obtained by adding an aluminum oxide such as sodium aluminate to an aqueous sodium hydroxide solution at room temperature and dissolving it, and then adding silica and stirring and mixing. It is preferable that the seed crystals are added while being mixed with the silica or after the silica is added, and then the mixture is stirred and mixed so that the seed crystals are uniformly dispersed. The temperature in the contact step is also not particularly limited, and is generally room temperature (20 to 25° C.).

[0035] The contact product containing the components (α) to (ε) can be put into a sealed container, for example, and heated in the above-mentioned temperature range to react, to obtain a crystalline aluminosilicate (A1). It is preferable that this reaction mixture does not contain a structure-directing agent (hereinafter, sometimes referred to as "SDA"). As described above, SDA is generally expensive, and since it is often altered or decomposed in the contact with acid or in the calcination process described below, it is difficult to recover or reuse it, which may increase the production cost. In addition, after the contact at 100 to 200 ° C., a so-called aging process can be provided in which the temperature is kept lower than that temperature. In such an aging process, it is preferable to leave the mixture stationary without stirring. By carrying out aging, it is possible to prevent the by-production of impurities.

[0036] The preferred temperature and time for the aging can be set so as to maximize the above-mentioned effects. The aging is preferably carried out at a temperature of 20 to 80° C., more preferably 20 to 60° C., for a period of preferably 2 hours to 1 day.

[0037] When stirring is performed to make the temperature uniform during the contact at 100 to 200°C, it is preferable to heat and stir after the aging. This method is expected to further prevent the by-production of impurities. The stirring can be performed by any known method, such as mixing with a stirring blade or mixing by rotating a container, without any restrictions. The stirring intensity and rotation speed may be adjusted according to the uniformity of the temperature and the degree of by-production of impurities. Intermittent stirring may be used instead of constant stirring. Combining aging and stirring in this way may be advantageous for industrial mass production.

[0038] In step 1, it is preferable not to use a structure-directing agent such as a quaternary ammonium salt. Such structure-directing agents are generally expensive and often cannot be recovered. In the present invention, since the aluminosilicate (A1) is produced under specific conditions such as the above-mentioned i) to v), even the aluminosilicate (A1) obtained in the absence of a structure-directing agent is an aluminosilicate raw material suitable for preparing a catalyst for producing an aromatic dihydroxy compound, which will be described later.

[0039] (Process 2) In step 2, the aluminosilicate (A1) obtained in step 1 is contacted with an acid two or more times, and then calcined (primary calcination).

[0040] Examples of the acid include inorganic acids, organic acids, and mixtures thereof, and specific examples of the acid include nitric acid, hydrochloric acid, sulfuric acid, citric acid, oxalic acid, and mixtures thereof. Among these, acids containing elements selected from the elements of Groups 15 and 16 of the periodic table are preferred, and nitric acid is more preferred.

[0041] The concentration of the acid is not particularly limited, but is preferably 5% by weight to 80% by weight, and more preferably 40% by weight to 80% by weight. When these acids are used as an aqueous solution, the concentration may be expressed as a molar concentration or a specified number (N). A preferred concentration range in terms of molar concentration is, for example, 0.01 mol / L to 50 mol / L. A more preferred lower limit is 0.03 mol / L, even more preferably 0.05 mol / L, and particularly preferably 0.07 mol / L. On the other hand, a more preferred upper limit is 40 mol / L, even more preferably 30 mol / L, and particularly preferably 20 mol / L.

[0042] In step 2 of the present invention, the aluminosilicate (A1) is contacted with the acid two or more times. In this case, the concentrations of the acids used may be the same or different. The conditions are preferably different concentrations. When the conditions are different concentrations, the difference in concentration is preferably 3 mol / L or more and 20 mol / L or less. The lower limit of the concentration difference is more preferably 5 mol / L, even more preferably 7 mol / L, particularly preferably 9 mol / L, and especially preferably 10 mol / L. On the other hand, the upper limit is more preferably 18 mol / L, even more preferably 16 mol / L, and particularly preferably 15 mol / L.

[0043] When the aluminosilicate (A1) is contacted with the acid having different concentrations two or more times, it is preferable to contact it with the acid having a high concentration after contacting it with the acid having a low concentration. The concentration range of the acid having a low concentration is preferably 0.01 to 5 mol / L. The more preferable lower limit is 0.03 mol / L, more preferably 0.05 mol / L, and particularly preferably 0.07 mol / L. On the other hand, the more preferable upper limit is 1.7 mol / L, more preferably 1.5 mol / L, and particularly preferably 1.3 mol / L. The concentration range of the acid having a high concentration is preferably 6 to 50 mol / L. The more preferable lower limit is 8 mol / L, more preferably 9 mol / L, and particularly preferably 10 mol / L. On the other hand, the more preferable upper limit is 40 mol / L, more preferably 30 mol / L, and particularly preferably 20 mol / L.

[0044] In step 2, the acid is preferably contacted in an amount of 10 to 100 parts by weight, more preferably 20 to 100 parts by weight, per part by weight of the aluminosilicate (A1).

[0045] As described above, in Patent Documents 7 and 8, an ion exchange step and a steam treatment step are used in addition to the step of contacting with an acid. Patent Document 8 also discloses that the zeolite crystal structure may be destroyed without the ion exchange step and the steam treatment step.

[0046] In the present invention, an aluminosilicate (A2) is produced by contacting an aluminosilicate (A1) with an acid two or more times, and a modified aluminosilicate produced using the aluminosilicate (A2) surprisingly exhibits high performance as a catalyst for producing an aromatic dihydroxy compound, described below, even without the ion exchange step and steam treatment step. The reason for such an unexpected effect is not clear at present, but the present inventors hypothesize the following.

[0047] If the aluminosilicate (A1) is brought into contact with acid without carrying out the ion exchange step and the steam treatment step, the structure of the aluminosilicate may indeed be destroyed. This is thought to be because the aluminum content of the aluminosilicate (A1) obtained in step 1 is relatively high, and the structure is likely to become unstable after the aluminum elimination reaction by acid. On the other hand, a phenomenon in which Si migrates to the unstable sites (Si-migration) may also occur, stabilizing the crystal structure. If the aluminosilicate is brought into contact with a low concentration acid, the effect of Si-migration becomes relatively dominant, and the crystal structure is likely to be stabilized.

[0048] In addition to the above, one of the reasons for this is thought to be that not only is aluminum removed, but also the reaction between the remaining alkali metals and the acid occurs at the same time, preventing the smooth removal of aluminum from the aluminosilicate. It is also thought that the presence of alkali metals may inhibit the above-mentioned Si-migration. In addition, since the aluminum content of the aluminosilicate (A1) is high, it is likely that aluminum is removed insufficiently, making it difficult to exhibit the performance of the catalyst described below.

[0049] On the other hand, in the method of the present invention, the aluminosilicate is contacted with acid from the second time onwards, so that the stabilization of the crystal structure by the Si-migration is more likely to proceed, and the elimination of aluminum also proceeds sufficiently, so that the destruction is suppressed, and an excellent aluminosilicate with a high Si / Al molar ratio is obtained. Therefore, it is considered that a high acid concentration is a preferable condition in the contact process with acid from the second time onwards. In addition, since the environment is low in excess alkali metal, it is also considered that the environment in which the elimination of aluminum is more likely to occur preferentially is preferable from the viewpoint of increasing the Si / Al molar ratio. The aluminosilicate obtained by the above-mentioned process may have a structure with slight destruction in part, and it is considered that this unstable site may be a factor in forming a suitable active species for the catalyst for producing aromatic dihydroxy compounds.

[0050] As described above, in the present invention, it is preferable to contact the aluminosilicate (A1) under conditions of different acid concentrations. It is particularly preferable to first carry out contact under low-concentration conditions.

[0051] If a low concentration acid is used in the contact step between the aluminosilicate (A1) and the acid, the reaction with the remaining alkali metal is probably prioritized, and the amount of aluminum released is relatively small, and as a result, it is expected that the aluminosilicate structure described above can be reduced. Therefore, it is possible that a part of the aluminum can be released efficiently without placing too much strain on the aluminosilicate structure. In addition, the somewhat unstable structure formed at this time may be a suitable structure for use as a catalyst for producing aromatic dihydroxy compounds.

[0052] As described above, in the present invention, contacting the aluminosilicate (A1) with an acid two or more times is expected to bring about unexpected effects.

[0053] The temperature condition when the aluminosilicate (A1) is contacted with the acid is preferably 50° C. to 170° C., more preferably 100° C. to 170° C. The contact time is preferably 5 hours to 48 hours, more preferably 12 hours to 36 hours per time. An even more preferable lower limit of the time is 18 hours.

[0054] The contact product obtained as described above is preferably washed with a medium such as water to remove excess acid. This step may be considered as a washing step, and a well-known or publicly known method can be used without any restrictions. For example, it is preferable to filter the contact product using a Nutsche filter or the like to separate the excess acid (aqueous solution) and the like, and then wash the filtrate with water and dry it. It is preferable to perform the washing step while keeping the product in a wet state without drying it. There are no particular restrictions on the drying method, but it is preferable to dry the product uniformly and quickly, and for example, an external heating method such as hot air drying or superheated steam drying, or an electromagnetic heating method such as microwave heating drying or high-frequency dielectric heating drying can be used.

[0055] It is believed that the contact of this aluminosilicate (A1) with acid mainly removes a portion of the aluminum from the aluminosilicate (A1). In particular, it is speculated that the aluminum on the surface of the aluminosilicate (A1) tends to be removed. It is speculated that the treatment under the conditions of relatively high temperature and long time as described above makes it easier to form a structure that is advantageous for the introduction of the group 4 and group 5 elements in the firing step described later.

[0056] In step 2, the contact product obtained by contacting the aluminosilicate (A1) with an acid is calcined to obtain an aluminosilicate (A2). The method is not particularly limited, and examples thereof include a method of calcining using an electric furnace, a gas furnace, or the like. As for the calcination conditions, heating in an air atmosphere for 0.1 to 20 hours is preferable. The calcination temperature is 550°C to 850°C, and more preferably 600°C to 800°C. It is presumed that the primary calcination in this relatively high temperature environment provides an environment more favorable for the formation of a modified aluminosilicate containing Group 4 and Group 5 elements, typically titanium species, in a highly active state.

[0057] (Step 3) In step 3 of the present invention, the aluminosilicate (A2) is contacted with a compound (B) having one or more elements selected from Groups 4 and 5 of the periodic table, and then calcined (secondary calcination) to obtain a modified aluminosilicate (A3). In this step, as described above, it is believed that the aluminum removed by the acid is replaced with atoms of one or more elements selected from Groups 4 and 5 of the periodic table.

[0058] The aluminosilicate (A2) used here preferably does not contain any Group 4 or Group 5 elements, or if it does contain any, it is to the extent that it does not affect the effects of the present invention. Examples of the Group 4 elements include titanium, zirconium, and hafnium. Examples of the Group 5 elements include vanadium. Among these elements, the Group 4 elements are preferred, titanium, zirconium, and hafnium are more preferred, and titanium is even more preferred. The above elements may be used alone or in combination of two or more.

[0059] In step 3, the aluminosilicate (A2) is contacted with a compound (B) containing one or more elements selected from the group 4 and group 5 elements of the periodic table. These compounds can be contacted in a liquid phase or a gas phase, but are preferably contacted in a liquid phase.

[0060] A known method can be adopted as a method for contacting the compound (B) in a gas phase. For example, a method can be mentioned in which an inert gas such as nitrogen is passed through the liquid compound (B) to form a gas flow containing the compound (B), and this gas flow is introduced into the aluminosilicate (A2). The temperature at this time is preferably 400°C or higher and 1000°C or lower. A more preferred lower limit is 450°C, and even more preferred is 500°C. On the other hand, a more preferred upper limit is 900°C, and even more preferred is 800°C, and particularly preferred is 700°C.

[0061] The method of contacting the compound (B) in a liquid state with the aluminosilicate (A2) can be any known method without limitation. Hereinafter, the most preferred embodiment using a titanium-containing liquid (a titanium source in a liquid phase) will be described as a representative example.

[0062] The liquid-phase titanium source is a liquid containing titanium. Examples of the titanium-containing liquid include a liquid titanium compound itself and an aqueous solution of a titanium compound. Among them, a titanium compound that is substantially acidic in a liquid state is a preferred embodiment.

[0063] Examples of liquid titanium compounds include titanium tetrachloride (TiCl4) and tedrabbutoxytitanium, among which titanium tetrachloride is preferred. Examples of aqueous solutions of titanium compounds include aqueous titanium tetrachloride, aqueous titanium trichloride (TiCl3), aqueous titanium sulfate (Ti(SO4)2), and aqueous potassium hexafluorotitanate, among which titanium tetrachloride, aqueous titanium trichloride, and aqueous titanium sulfate are preferred. In the present invention, even when titanium sources having low reactivity such as titanium trichloride and titanium sulfate are used in addition to titanium tetrachloride, the catalytic activity described below can be expressed. In addition, these titanium-containing liquids can be used alone or in combination of two or more. The titanium-containing liquid can be a commercially available product, or can be appropriately prepared by diluting a solid titanium compound with water to a desired concentration. Compared to a gaseous titanium source, a liquid titanium source is less likely to leak, and the problem of corrosion to manufacturing machines, analytical instruments, and the like is improved, making industrial production easier to carry out.

[0064] The conditions for adding the titanium source to the aluminosilicate (A2) are not particularly limited. For example, when a liquid titanium compound is used, it is preferable to add 5 to 300 parts by weight, more preferably 20 to 250 parts by weight, of the liquid titanium compound per part by weight of the primary calcination product. When an aqueous solution of a titanium compound is used, it is preferable to add 1 to 10 parts by weight, more preferably 1 to 7 parts by weight, of the aqueous solution of the titanium compound per part by weight of the primary calcination product. The concentration of the aqueous solution varies depending on the compound used, but is, for example, 10 to 70% by weight, preferably 15 to 60% by weight.

[0065] The amount of the titanium compound in the aqueous solution is preferably 0.1 parts by weight, more preferably 0.2 parts by weight, even more preferably 0.3 parts by weight, and particularly preferably 0.5 parts by weight, per part by weight of the primary fired product, while the upper limit is preferably 10 parts by weight, more preferably 5 parts by weight, and even more preferably 3 parts by weight.

[0066] When the titanium source is added, it may be added all at once, or may be added in several portions by repeating step 3, so long as the total amount added is within the range of the amount added. For example, the titanium source may be added to the primary calcination product, and the calcination product obtained by drying and secondary calcination described below may be added again to the calcination product, which may then be dried and secondary calcined. When the titanium source is added, it is preferable to carry out the addition under a nitrogen atmosphere, since hydrogen chloride is generated by the reaction between moisture in the air and the titanium compound.

[0067] After the aluminosilicate (A2) and the titanium source are sufficiently contacted with each other, the contact product is subjected to a calcination step. Preferably, the contact product is sufficiently dried by heating at a relatively low temperature or by using the drying method described in step 2, and then calcined. The temperature in the heating and drying steps is not particularly limited, but for example, in order to effectively introduce titanium into the aluminosilicate, the temperature is preferably in the range of 0 to 150°C. A more preferable lower limit is 10°C, even more preferably 15°C, and particularly preferably 20°C. On the other hand, a more preferable upper limit is 140°C, even more preferably 120°C, and particularly preferably 100°C. The time required for the steps is also not particularly limited, but is preferably 0.1 to 24 hours. A more preferable lower limit is 0.3 hours, even more preferably 0.4 hours, and particularly preferably 0.5 hours. On the other hand, a more preferable upper limit is 12 hours, and more preferably 6 hours. The calcination method is not particularly limited, and calcination can be performed using, for example, an electric furnace, a gas furnace, or the like. Calcination conditions are 400°C or higher and 800°C or lower in the air for 0.1 to 20 hours. This step makes it possible to obtain an aluminotitanosilicate (A3-Ti) in which a portion of the aluminum in the crystalline porous aluminosilicate is thought to have been substituted with titanium.

[0068] Before carrying out the drying step, the mixture of the titanium source and the primary calcined product may be heated to preliminarily remove moisture, the mixture may be filtered to remove impurities, and then the mixture may be washed with an organic solvent, after which the secondary calcination may be carried out. The above-mentioned manufacturing conditions can be applied mutatis mutandis to the case where an element other than titanium is used.

[0069] Examples of compounds containing Group 4 elements of the periodic table that can be used in place of the titanium source include zirconium tetrachloride, tetraalkoxyzirconium, hafnium tetrachloride, tetraalkoxyhafnium, zirconium sulfate, etc., which can be liquefied by combining with water, alcohol, ether, etc. as necessary. Examples of such compounds include aqueous solutions, alcohol, ether, etc. solutions. Examples of Group 5 elements of the periodic table that can be used in place of the titanium source include vanadium pentachloride, vanadium sulfate, vanadyl trichloride, and alkoxy-substituted vanadium pentachloride, etc., which can be liquefied by combining with water, alcohol, ether, etc. as necessary. Examples of such aqueous solutions, alcohol, ether, etc. solutions can be liquefied by combining with water, alcohol, ether, etc. as necessary.

[0070] (Modified Aluminosilicate (A3)) The modified aluminosilicate (A3) of the present invention is preferably crystalline and porous, similar to the raw material aluminosilicate. The crystallinity may be considered to be the same as that described for the raw material aluminosilicate.

[0071] It is well known that porous compounds have a large specific surface area. The modified aluminosilicate (A3) of the present invention preferably has a specific surface area of ​​50 to 1000 m. 2 The lower limit of the specific surface area is more preferably 100 m 2 / g, more preferably 150m 2 On the other hand, the upper limit of the specific surface area is more preferably 800 m 2 / g, more preferably 600m 2 The specific surface area is 1 / g. The specific surface area can be determined by a known calculation method based on the BET theory by creating a BET plot from the measurement results using a known nitrogen adsorption / desorption measuring device (e.g., Microtrac BELSORP-max manufactured by BEL).

[0072] The preferred range of the pore volume of the modified aluminosilicate (A3) of the present invention is 0.1 to 0.5 cm. 3 / g, more preferably 0.2 to 0.4 cm 3 / g.

[0073] The modified aluminosilicate (A3) of the present invention may be characterized by absorption in a specific wavelength region in ultraviolet-visible absorption spectrum measurement.

[0074] The modified aluminosilicate (A3) in the present invention may preferably contain one or more elements selected from the group consisting of Group 4 and Group 5 elements of the periodic table, and exhibit an absorbance at 300 nm in the ultraviolet-visible spectrum (A

[0300] ) of 1.0 or more. The ultraviolet-visible spectrum is a value obtained by measuring by a conventional method using a cell with an optical path length of 10 mm containing 0.1 g of the modified aluminosilicate (A3) as a sample.

[0075] There is no particular restriction on the contents of Group 4 and Group 5 elements contained in the modified aluminosilicate (A3) of the present invention. For example, when titanium is contained as one or more elements selected from the group consisting of Group 4 and Group 5 elements contained in the modified aluminosilicate (A3), the molar ratio of silicon to titanium ([Si] / [Ti]) is preferably in the range of 0.1 to 100, more preferably in the range of 0.5 to 50, even more preferably in the range of 1 to 30, and most preferably in the range of 2 to 30.

[0076] When a compound that easily crystallizes itself, such as TiCl3, is used, the element may be introduced to the aluminosilicate surface in the form of a cluster or a crystal. In this case, the apparent element content may increase, so the [Si] / [Ti] ratio tends to be small. In such a case, the range of the [Si] / [Ti] ratio is preferably 0.5 to 30. The more preferred lower limit is 1, and more preferably 1.2. On the other hand, the more preferred upper limit is 20, and more preferably 15.

[0077] The aluminum content of the modified aluminosilicate (A3) of the present invention is not particularly limited, but the molar ratio of silicon to aluminum ([Si] / [Al]) is preferably in the range of 5 to 100,000, more preferably in the range of 10 to 10,000, and most preferably in the range of 100 to 1,000.

[0078] In addition, the ratio of A

[0300] to the absorbance (A

[0210] ) at 210 nm in the ultraviolet-visible absorption spectrum (A

[0300] / A

[0210] ) is preferably 0.1 or more, more preferably 0.13 or more, and even more preferably 0.15 or more. For example, when titanium is incorporated without defects into the framework of the crystal structure, A

[0210] is relatively high compared to A

[0300] , so that A

[0300] / A

[0210] tends to be low in ordinary crystalline porous aluminotitanosilicates. There is no particular meaning to the upper limit of the A

[0300] / A

[0210] , but it is preferably 1.5, more preferably 1.0, and particularly preferably 0.5.

[0079] <Method of producing aromatic dihydroxy compound> One embodiment of the present invention is a method for producing an aromatic dihydroxy compound by reacting a phenol with hydrogen peroxide in the presence of the modified aluminosilicate (A3), which will be described below.

[0080] The phenols used in the present invention refer to unsubstituted phenol and substituted phenol, and examples of the substituted phenol include alkylphenols substituted with a linear or branched alkyl group having 1 to 6 carbon atoms, such as a methyl group, an ethyl group, an isopropyl group, a butyl group, or a hexyl group, or a cycloalkyl group.

[0081] Examples of phenols include phenol, 2-methylphenol, 3-methylphenol, 2,6-dimethylphenol, 2,3,5-trimethylphenol, 2-ethylphenol, 3-isopropylphenol, 2-butylphenol, and 2-cyclohexylphenol, and among these, phenol is preferred. When the phenol has a substituent at both the 2-position and the 6-position, the product is only a hydroquinone derivative.

[0082] Examples of aromatic dihydroxy compounds that are reaction products include hydroquinones (substituted or unsubstituted hydroquinone) and catechols (substituted or unsubstituted catechol). Specific examples of these include hydroquinone, catechol, 2-methylhydroquinone, 3-methylcatechol, 4-methylcatechol, 3-methylhydroquinone, 1,4-dimethylhydroquinone, 1,4-dimethylcatechol, 3,5-dimethylcatechol, 2,3-dimethylhydroquinone, and 2,3-dimethylcatechol.

[0083] The modified aluminosilicate (A3) obtained in one embodiment of the present invention is used as a catalyst for producing an aromatic dihydroxy compound. Various methods such as a fixed bed, a fluidized bed, a suspension bed, and a tray fixed bed are adopted as the catalyst packing method, and any method may be used. The catalyst may be used as it is, or may be molded according to the catalyst packing method. The catalyst is generally molded by extrusion molding, tablet molding, rolling granulation, spray granulation, etc., when the catalyst is used in a fixed bed method, extrusion molding or tablet molding is preferable. In the case of a suspension bed method, spray granulation is preferable. Drying or calcination may be performed after spray granulation. The average particle size of the spray granulated catalyst is preferably in the range of 0.1 μm to 1000 μm, more preferably 5 μm to 100 μm. If it is 0.1 μm or more, it is preferable because the handling such as filtration of the catalyst is easy, and if it is 1000 μm or less, it is preferable because the catalyst has good performance and high strength.

[0084] The amount of the catalyst used is preferably 0.1 to 30% by mass, more preferably 0.4 to 20% by mass, based on the total mass of the reaction liquid (the total mass of liquid components in the reaction system, not including the mass of fixed components such as the catalyst). If it is 0.1% by mass or more, the reaction is completed in a short time, which is preferable since the productivity is improved. If it is 30% by mass or less, the amount of catalyst separated and recovered is small.

[0085] When the modified aluminosilicate (A3) is used as a catalyst in the process for producing an aromatic dihydroxy compound, it may be combined with other components. For example, the siloxane compounds described in Patent Document 1 and the specific alcohol compounds described in Patent Document 2 may be used. Such components are preferably used in an amount of 5 to 90% by mass, more preferably 8 to 90% by mass, of the reaction liquid.

[0086] The molar ratio of hydrogen peroxide to phenols is preferably 0.01 or more and 1 or less. The concentration of hydrogen peroxide used is not particularly limited, but a normal aqueous solution of 30% concentration may be used, or a higher concentration of hydrogen peroxide may be used as is, or diluted with a solvent that is inert to the reaction system. Examples of solvents used for dilution include alcohols and water. Hydrogen peroxide may be added all at once, or may be added gradually over time.

[0087] The reaction temperature is preferably in the range of 30° C. to 130° C., more preferably in the range of 40° C. to 100° C. Although the reaction proceeds at temperatures outside this range, the above range is preferred from the viewpoint of improving productivity. The reaction pressure is not particularly limited.

[0088] The reaction method is not particularly limited, and the reaction may be carried out in any of batch, semi-batch, and continuous modes. When the reaction is carried out in a continuous mode, the reaction may be carried out in a suspension bed homogeneous mixing tank, or in a fixed bed flow plug flow format, or a plurality of reactors may be connected in series and / or parallel. From the viewpoint of equipment costs, it is preferable that the number of reactors is 1 to 4. When a plurality of reactors are used, hydrogen peroxide may be added to them in portions.

[0089] In order to obtain an aromatic dihydroxy compound from the reaction liquid, the reaction liquid or the separated liquid containing the aromatic dihydroxy compound after the catalyst is separated may be subjected to a purification treatment such as removing unreacted components and by-products. The purification treatment is preferably performed on the separated liquid containing the aromatic dihydroxy compound after the catalyst is separated.

[0090] The purification method is not particularly limited, and specific examples include oil-water separation, extraction, distillation, crystallization, and combinations thereof. The purification method and procedure are not particularly limited, but for example, the separation liquid containing the aromatic dihydroxy compound after separation of the reaction liquid and the catalyst can be purified by the following method.

[0091] When the reaction liquid is separated into two phases, an oil phase and an aqueous phase, oil-water separation is possible. By oil-water separation, the aqueous phase with a low content of aromatic dihydroxy compounds is removed and the oil phase is recovered. In this case, the separated aqueous phase may be subjected to extraction or distillation to recover the aromatic dihydroxy compounds, or a part or all of it may be used again in the reaction. In addition, the catalyst separated in the catalyst separation step or the catalyst that has been dried may be dispersed in the separated aqueous phase and supplied to the reactor. On the other hand, it is desirable to further purify the oil phase by extraction, distillation, crystallization, etc.

[0092] For extraction, solvents such as 1-butanol, toluene, isopropyl ether, and methyl isobutyl ketone are used. Combining extraction with oil-water separation allows the oil-water separation to be carried out efficiently. It is preferable to separate and recover the extraction solvent using a distillation column and recycle it for use.

[0093] The distillation may be carried out on the reaction liquid immediately after the catalyst separation, or on the oil phase and the aqueous phase after the oil-aqueous separation. When distilling the reaction liquid immediately after separation of the catalyst, it is preferable to first separate low-boiling components such as water and alcohols. Water and alcohols may be separated in separate distillation columns, or may be separated in a single distillation column.

[0094] After separating water and alcohols by the above-mentioned oil-water separation, extraction, distillation, etc., the phenols may be recovered by the next distillation operation and used again in the reaction. If the recovered phenols contain water that has not been completely separated, it can be removed by azeotropic distillation after adding isopropyl ether or toluene.

[0095] This azeotropic distillation can also be performed on water before recovery of phenols or on the liquid after separation of alcohols. The separated water can be reused in the reaction or can be treated as waste water. When the recovered phenols contain impurities such as reaction by-products other than water, they can be further separated by a distillation operation. When the impurities are benzoquinones, which are reaction by-products, they can be fed again to the reactor together with the phenols.

[0096] After separation of the phenols, components with higher boiling points than the aromatic dihydroxy compounds are removed by distillation, and the hydroquinones and catechols can be separated by the next distillation operation. The high boiling points, hydroquinones, and catechols can also be separated in a single distillation operation by withdrawing the hydroquinones from the middle of the distillation column. The resulting hydroquinones and catechols can be subjected to distillation or crystallization to remove impurities and increase the purity, if necessary.

[0097] In the presence of the modified aluminosilicate (A3) of the present invention, for example, when phenol and hydrogen peroxide are reacted, hydroquinone tends to be produced in a high yield. In addition, hydroquinone tends to be produced with a high selectivity compared to catechol, benzoquinone, etc. Therefore, it can be said that the modified aluminosilicate (A3) of the present invention has high industrial value. EXAMPLES

[0098] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples in any way.

[0099] In the examples, the measurement methods and conditions are as follows. [XRD measurement] Device: Rigaku Ultima IV (Protectus) device X-ray source:CuKα:1.545Å Voltage: 40kV Current: 20mA Measurement range: 2θ=2.0~52° Scanning speed: 2° / min Sampling interval 0.020° Divergence slit: 1 / 2°, scattering slit: 1.00mm, receiving slit: 0.15mm [Gas Chromatography] Equipment: Shimadzu GC-14 type equipment Column: DB-1 capillary column 30m * 0.25mmφ * 1.0mm Detector: FID Carrier gas: Helium Injection temperature: 250℃ Detector temperature: 250℃ Column temperature conditions: Initial 60℃ * 2 minutes Then, the temperature was increased to 200°C at a rate of 10°C / min. [Oxidation-reduction titration] Device: Kyoto Electronics Industry automatic potential difference lowering device AT-500N type device

[0100] (Production Example 1) (Preparation of seed crystals (MCM-68 type zeolite)) 15.02 g (100 mmol-SiO2) of colloidal silica (product name: LUDOX (registered trademark) HS-40, manufactured by DuPont, 40% by mass) and 20.5 g of pure water (product name: milliQ) were mixed and stirred for about 10 minutes. (The total amount of water at this point was 1500 mmol.)

[0101] To this was added 0.91 g (10 mmol-Al) of aluminum hydroxide (Pfaltz & Bauer), 6.19 g (37.5 mmol-K) of aqueous potassium hydroxide solution (Fujifilm Wako Pure Chemical Industries, Ltd.), and 20.33 g of pure water, and the mixture was stirred for 30 minutes. Furthermore, 5.59 g (10 mmol-N) of N,N,N',N'-tetraethylbicyclo[2,2,2]oct-7-ene-2,3:5,6-dipyrrodinium dichloride (hereinafter sometimes referred to as TEBOP) was added as a structure-directing agent, and the mixture was stirred for 4 hours to obtain a gel.

[0102] The gel was left to stand in an autoclave at 160°C for 16 days. The product was centrifuged until neutral, and then dried at 100°C to obtain 6.18g of a white powder. 5.32g of the white powder was heated at a rate of 1°C / min, and after reaching 650°C, the temperature was maintained for 10 hours, and then allowed to cool to obtain 4.45g of aluminosilicate crystals (MCM-68 type). (No structure-directing agent (TEBOP) was detected.) These were used as seed crystals in the examples and comparative examples described below.

[0103] Example 1 (Preparation of raw aluminosilicate) 12.68 grams (80.14 millimoles of sodium) of aqueous sodium hydroxide solution (6.32 millimoles / g) and 996 milligrams (5.94 millimoles of potassium) of aqueous potassium hydroxide solution (5.96 millimoles / g) manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. were weighed out and mixed with 43.84 grams of pure water to prepare an aqueous solution with a total water content of 3.00 moles in a Teflon (registered trademark) cup. 443 milligrams of sodium aluminate (containing 34.5 wt% Al2O3 and 27.5 wt% Na2O) was added and dissolved in the solution.

[0104] The solution was transferred to a mortar, and the mixture to which 901 milligrams of the calcined seed crystals had been added was homogenized with a pestle for 10 minutes. Then, 150 millimoles of silica (Cab-O-sil M5: manufactured by Cabot Corporation) was added, and the mixture was homogenized again with a pestle for 20 to 30 minutes. The mixture was transferred to a 60-mL stainless steel autoclave, sealed, and subjected to hydrothermal synthesis at 140° C. for 48 hours under stationary conditions to obtain a mixture containing a solid product.

[0105] The synthesis mixture containing the solid product produced above was suction filtered using filter paper (5C), and the solid portion remaining on the filter paper was washed with distilled water until the filtrate became neutral. The solid portion was dried at 80°C to obtain 1.53 g of a white powder (aluminosilicate (A1-1)). The above experiment was repeated multiple times to obtain similar white powders. These white powders were analyzed by the usual method using the ICP method (using a Shimadzu ICP8000E type device) to determine the molar ratio (atomic ratio) of silicon to aluminum. (The Si / Al ratio was in the range of 5 to 7.)

[0106] (Contact between white powder (aluminosilicate) and nitric acid) 0.75 g of the white powder (aluminosilicate (A1-1)) was mixed with 45.7 ml of 0.1 mol / L nitric acid aqueous solution (white powder: nitric acid aqueous solution = 1 g: 60 ml) and stirred for 24 hours under heating and reflux conditions. The synthesis mixture containing the resulting solid product was suction filtered using filter paper (5C), and the solid portion remaining on the filter paper was washed with distilled water until the filtrate became neutral, and dried at 80 ° C. to obtain a white powder. Next, the white powder was contacted with nitric acid and stirred in the same manner as above, except that the obtained white powder and a 13.4 mol / L nitric acid aqueous solution were used, to obtain a white powder (aluminosilicate (A2-1)).

[0107] (Preparation of titanium modified aluminosilicate) 0.4 g of the white powder (aluminosilicate (A2-1)) was mixed with 4.97 g of titanium tetrachloride aqueous solution (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and stirred at 25° C. for 1 hour. After that, it was washed with a separatory funnel until it became neutral, and then dried at 80° C. to obtain 0.36 g of a solid. Next, 0.20 g of the obtained solid was heated at a rate of 1° C. / min, and after reaching 650° C., the same temperature was maintained for 4 hours, and then allowed to cool to obtain 0.18 g of a modified aluminosilicate (A3-1). By XRD measurement, the modified aluminosilicate (A3-1) had an MSE type skeleton.

[0108] (Reaction of phenol with hydrogen peroxide) 20 mg of the modified aluminosilicate (A3-1), 21.25 mmol of phenol, and 4.25 mmol of hydrogen peroxide (30% by mass)-H2O2 were mixed in a pressure vessel and reacted at 100°C for 10 minutes.

[0109] After the reaction was completed, the pressure vessel was cooled with ice, and 2.0 g of sulfolane and 0.225 g of anisole (internal standard substance for gas chromatography) were added and mixed thoroughly, followed by solid-liquid separation by centrifugation. 9 equivalents of acetic anhydride and 10 equivalents of potassium carbonate were added to 0.1 g of the obtained liquid phase for acetylation. 3.5 ml of chloroform was added to this solution, and 2 ml of the solution was collected and subjected to solid-liquid separation using a filter. The obtained solution was analyzed for the content of components such as hydroquinone and cresol using a gas chromatograph.

[0110] On the other hand, 0.5 g of the reaction solution was mixed with 50 mL of 2 mol / L hydrochloric acid and 0.8 g of potassium iodide and thoroughly stirred, after which the amount of unreacted hydrogen peroxide was analyzed by oxidation-reduction titration using a 0.1 mol / L aqueous solution of sodium thiosulfate, and the yield on hydrogen peroxide was determined by a conventional method. The results are summarized in Table 1.

[0111] Example 2 (Preparation of titanium modified aluminosilicate) A quartz tube was charged with 0.376 g of aluminosilicate (A2-1) and quartz wool. Argon gas was supplied to the quartz tube at a rate of 30 ml / min. The temperature of the supplied argon gas was raised to 600°C over 4 hours to heat the aluminosilicate (A2-1). Separately, titanium tetrachloride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., purity 99%) was inserted into a bubbler tube, and the 600°C argon gas was supplied to it to prepare a 600°C argon gas flow containing titanium tetrachloride, which was supplied to the quartz tube for 1 hour. Thereafter, the flow was switched to a 600°C argon gas flow, which was supplied to the quartz tube for 1 hour. Thereafter, the tube was gradually cooled under the argon gas flow, and the contents were washed with distilled water and then dried to obtain a white powder.

[0112] The obtained white powder was heated at a rate of 1°C / min, and after reaching 650°C, the temperature was maintained for 4 hours, and then allowed to cool to obtain a modified aluminosilicate (A3-2). The modified aluminosilicate (A3-2) had an MSE type structure according to XRD measurement.

[0113] (Reaction of phenol with hydrogen peroxide) Except for using the modified aluminosilicate (A3-2) as the catalyst, the same procedure as in Example 1 was repeated. The results are shown in Table 1.

[0114] Comparative Example 1 (Ion exchange of aluminosilicate (A1-1) / steam treatment / contact with acid) Ion exchange treatment 0.61 g of the aluminosilicate (A1-1) was dispersed in an aqueous solution of ammonium nitrate (a solution in which 1.22 g of ammonium nitrate was dissolved in 30.5 g of distilled water). This dispersion was sealed in a heat-resistant sealed container and left to stand in a thermostatic bath at 80°C for 24 hours to carry out ion exchange. Thereafter, suction filtration was carried out using filter paper (5C) to filter out the aluminosilicate. This series of operations was repeated two more times (however, the standing time was 20 hours each time). The solid remaining on the filter paper was thoroughly washed with distilled water and dried at 80°C to obtain 0.51 g of ammonium-type aluminosilicate.

[0115] Steam Treatment The same method as in Example 1 of Japanese Patent No. 6083903 was used. The amount of filling was 0.46 g. Under a heated state of 500°C, a mixed gas of argon and water vapor was continuously passed for 24 hours. The partial pressure of the water vapor was 10 kPa. Upon exposure to water vapor, the aluminosilicate was converted from the ammonium type to the proton type. 0.32 g of the proton type aluminosilicate was obtained.

[0116] Contact with acid 0.32 g of the aluminosilicate after the steam treatment was mixed with 9.6 mL of 13.4 mol / L nitric acid aqueous solution (white powder: nitric acid aqueous solution = 1 g: 30 mL), and stirred for 24 hours under heating and reflux conditions. After filtering, washing, and drying, 0.25 g of aluminosilicate (C2-1) was obtained.

[0117] (Preparation of Modified Aluminosilicate) The same procedures as in Example 1 were carried out except that the aluminosilicate (C2-1) was used, to obtain a modified aluminosilicate (C3-1).

[0118] (Reaction of phenol with hydrogen peroxide) Except for using the modified aluminosilicate (C3-1) as the catalyst, the same procedure as in Example 1 was repeated. The results are shown in Table 1.

[0119] [Table 1]

[0120] From the above results, it is understood that by contacting an aluminosilicate with an acid two or more times, a modified aluminosilicate that serves as an excellent catalyst for producing aromatic dihydroxy compounds such as hydroquinone can be obtained.

[0121] Comparative Example 2 (Contact between white powder (aluminosilicate) and nitric acid) 0.75 g of the white powder (aluminosilicate (A1-1)) was mixed with 45.7 mL of 13.4 mol / L nitric acid aqueous solution (white powder: nitric acid aqueous solution = 1 g: 60 mL), and the mixture was stirred for 24 hours under heating and reflux conditions. The resulting product was washed using a separatory funnel until it became neutral, and then dried at 80°C to obtain a white powder (aluminosilicate C2-2). XRD measurement of the aluminosilicate (C2-2) revealed destruction of the crystal structure. For this reason, a modified aluminosilicate was not prepared.

Claims

1. A method for producing a modified aluminosilicate, comprising the following steps 1 to 3. (Step 1) A process to prepare an aluminosilicate (A1) with a Si / Al ratio of 3 to 12.5 by contacting (α) silicon oxide, (β) aluminum oxide, (γ) alkali metal compound, (δ) water, and (ε) aluminosilicate crystal at 100 to 200°C under conditions satisfying iv) to v) below. iv) The component (ε) is an aluminosilicate crystal with a Si / Al (molar ratio) of 4 to 15. v) Component (ε) / Component (α): 0.1 to 20% by weight (Step 2) The process involves bringing the aluminosilicate (A1) into contact with an acid two or more times, and then firing it to prepare aluminosilicate (A2). (Step 3) The process involves contacting the aluminosilicate (A2) with a compound (B) containing one or more elements selected from the group consisting of Group 4 and Group 5 elements of the periodic table, and then firing it to prepare a modified aluminosilicate (A3).

2. The method for producing a modified aluminosilicate according to claim 1, wherein the compound (B) is a liquid compound.

3. A method for producing a modified aluminosilicate according to claim 1, wherein the concentrations of the acids are different when the aluminosilicate (A1) is brought into contact with the acid two or more times.

4. The method for producing a modified aluminosilicate according to claim 1, wherein step 1 is a step carried out in the absence of a structure-correcting agent.

5. A method for producing an aromatic dihydroxy compound, comprising the following steps. (Step 1) A process to prepare an aluminosilicate (A1) with a Si / Al ratio of 3 to 12.5 by contacting (α) silicon oxide, (β) aluminum oxide, (γ) alkali metal compound, (δ) water, and (ε) aluminosilicate crystal at 100 to 200°C under conditions satisfying iv) to v) below. iv) The component (ε) is an aluminosilicate crystal with a Si / Al (molar ratio) of 4 to 15. v) Component (ε) / Component (α): 0.1 to 20% by weight (Step 2) The process involves bringing the aluminosilicate (A1) into contact with an acid two or more times, and then firing it to prepare aluminosilicate (A2). (Step 3) The process involves contacting the aluminosilicate (A2) with a compound (B) containing one or more elements selected from the group consisting of Group 4 and Group 5 elements of the periodic table, and then firing it to prepare a modified aluminosilicate (A3). (Reaction process between phenols and hydrogen peroxide) The process involves reacting phenols with hydrogen peroxide in the presence of the modified aluminosilicate (A3).