JP4851998B2 - Method for producing titanosilicate and method for producing oxime - Google Patents

Description

  The present invention relates to a method for producing a titanosilicate having an MWW structure and an ammoximation reaction of a ketone with a peroxide and ammonia in the presence of the titanosilicate having an MWW structure obtained by the production method. And a method of manufacturing. Oxime is useful, for example, as a raw material for amides and lactams.

Conventionally, a titanosilicate having an MWW structure has been used as one of catalysts in a method for producing an oxime by an ammoximation reaction of a ketone with a peroxide and ammonia.
As a method for producing such titanosilicate, a silicon compound, a boron compound, a titanium compound, water and a structure-directing agent are mixed and then heat-treated (Non-patent Document 1), or a silicon compound, a boron compound, water and a structure-defining agent. A method has been proposed (Patent Document 1) in which a heat treatment is performed after mixing the agent, followed by filtration and washing, and then the resultant crystal and the titanium compound are mixed and heat-treated again.

International Publication No. 03/0747421 Pamphlet Chemistry Letters, (Japan), 2000, p. 774-775

  However, the titanosilicate obtained by the method described in Non-Patent Document 1 is not always satisfactory in terms of the catalyst life of the titanosilicate. In addition, in the method described in Patent Document 1, after the first heat treatment, once filtered and washed to obtain crystals, the titanium compound is mixed and the second heat treatment is performed. It was disadvantageous in terms of cost.

  Accordingly, an object of the present invention is to provide a method for easily producing a titanosilicate having an excellent catalyst lifetime, and further, by carrying out an ammoximation reaction of a ketone at a high conversion rate, while maintaining the catalyst lifetime over a long period of time. An object of the present invention is to provide a method for producing an oxime with good selectivity.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors mixed a silicon compound, a boron compound, water and a structure directing agent, and then mixed a titanium compound with the suspension obtained by heat treatment. After the heat treatment again, it was found that the above-mentioned object can be achieved by separating the produced crystal and firing the crystal, thereby completing the present invention.

That is, the method for producing a titanosilicate having an MWW structure according to the present invention includes the following steps (1) to (5).
Step (1): Step of mixing silicon compound, boron compound, water and structure directing agent Step (2): Step of heat-treating the mixture obtained in Step (1) to obtain a suspension Step (3): Step Step (4) for mixing the suspension obtained in (2) and the titanium compound: Step (5): Step for separating the crystals formed after heat-treating the mixture obtained in Step (3) The step of firing the crystal obtained in (4)

  The oxime production method of the present invention is a method in which a ketone is ammoximation-reacted with a peroxide and ammonia in the presence of a titanosilicate having an MWW structure obtained by the method of producing the titanosilicate of the present invention. It is.

  According to the present invention, it is possible to easily produce a titanosilicate having an excellent catalyst life as a catalyst in a ketone ammoximation reaction. Then, in the presence of such titanosilicate, an oxime can be produced with a good selectivity while maintaining the catalyst life over a long period of time by causing the ketone to undergo an ammoximation reaction at a high conversion rate.

  The manufacturing method of the titanosilicate of this invention includes the process (1)-process (5) mentioned above. Hereinafter, each step will be described.

Step (1) is a step of mixing a silicon compound, a boron compound, water, and a structure directing agent.
Examples of the silicon compound include tetraalkyl orthosilicate such as tetraethyl orthosilicate, silica (fumed silica), and the like.
Examples of the boron compound include boric acid and anhydrous boric acid.
The structure directing agent is used as a template for forming a layered structure. For example, conventionally known structure directing agents such as piperidine and hexamethyleneimine can be used.
The proportion of each raw material used is 0.1 to 2 mol times as boron, 3 to 50 mol times as water, 3 to 50 mol times as water, and 0.3 as the structure directing agent based on silicon in the silicon compound. It is preferably ˜3 mole times.

  The raw materials (silicon compound, boron compound, water and structure directing agent) are preferably mixed at a temperature of 50 ° C. or less, more preferably 0 to 50 ° C., and even more preferably 10 to 50 ° C. It is good to do. The mixing of the raw materials is usually performed at room temperature. When the temperature at the time of mixing each raw material exceeds 50 degreeC, there exists a possibility that the production amount of an inactive titanium oxide particle may increase.

  There is no restriction | limiting in particular in the mixing method of each said raw material (a silicon compound, a boron compound, water, and a structure-directing agent), For example, all of these may be mixed collectively and may be mixed sequentially. . In particular, it is preferable to mix the raw material that is a liquid and then the raw material that is a solid after mixing the liquid raw material in advance because it is easy to uniformly stir.

  Step (2) is a step of obtaining a suspension by heat-treating the mixture obtained in step (1). In this step, the mixture of silicon compound, boron compound, water and structure directing agent is subjected to a hydrothermal synthesis reaction by heat treatment, resulting in a suspension. In the present invention, the heat treatment in this step is sometimes referred to as “first-stage hydrothermal synthesis reaction”.

  Hydrothermal synthesis refers to the synthesis and crystal growth method of substances carried out in the presence of high-temperature water, especially high-temperature and high-pressure water ("Iwanami Physical and Chemical Dictionary", 4th edition, Iwanami Shoten, 1987, p. Specifically, the raw materials are mixed, heated in an autoclave at a temperature of about 100 to 200 ° C. under a self-pressure, and stirred for several hours to several days. Conditions in the hydrothermal synthesis reaction are not particularly limited, and normal reaction conditions can be employed.

Step (3) is a step of mixing the suspension obtained in step (2) and the titanium compound.
Examples of the titanium compound include tetraalkyl orthotitanates such as tetra-n-butyl orthotitanate, peroxy titanates such as tetra-n-butyl ammonium peroxytitanate, and titanium halides.

  The amount of the titanium compound used is usually 0.01 to 0.10 mol, preferably 0.05 to 0.10 mol, based on titanium in the titanium compound, with respect to 1 mol of silicon in the silicon compound. This is good in terms of catalyst performance.

  Mixing of the suspension and the titanium compound is performed at a temperature lower than at least the reaction temperature during the hydrothermal synthesis reaction. The mixing is preferably performed at a temperature of 100 ° C. or lower, more preferably 50 ° C. or lower. Specifically, the titanium compound is usually added after the temperature of the suspension obtained in step (2) is lowered to about room temperature. For example, following the hydrothermal synthesis reaction in step (2), when the titanium compound is mixed with the suspension at the same temperature as the reaction temperature, the temperature at the time of mixing the suspension and the titanium compound is high. If the amount is too large, the amount of inactive titanium oxide particles produced may increase.

  When mixing the suspension and the titanium compound, together with these, other components (for example, any one or more of the silicon compound, boron compound, water, and structure directing agent mixed in step (1)). Can also be added. In that case, the other components are preferably mixed with the titanium compound in advance to form a uniform solution. There is no particular limitation on the method of mixing the suspension and the titanium compound (or a mixture of the titanium compound and other components). For example, both of them may be mixed at one time, You may mix by dripping one side or dropping both simultaneously.

  The start time of the step (3) (that is, the time to finish the first hydrothermal synthesis reaction in the step (2)) is not particularly limited, but for example, 10 days after the first day from the start of the first stage hydrothermal synthesis reaction. Within the range of 3 days and preferably 7 days or less is preferable in terms of productivity.

Step (4) is a step of separating the resulting crystals after heat-treating the mixture obtained in step (3). In this step, first, the mixture obtained in step (3) (that is, the mixture of the suspension and the titanium compound) is heat-treated and subjected to a hydrothermal synthesis reaction, and the resulting crystals are separated. To do. In the present invention, the heat treatment in this step is sometimes referred to as “second-stage hydrothermal synthesis reaction”.
The conditions for the second-stage hydrothermal synthesis reaction are not particularly limited, and may be the same as those described above as the conditions for the first-stage hydrothermal synthesis reaction. However, the total reaction time of the hydrothermal synthesis in the first stage and the second stage is preferably within 10 days in consideration of productivity.

  Crystals generated by the second-stage hydrothermal synthesis reaction are layered titanosilicates. Specifically, the layer structure of the layered titanosilicate can be confirmed by the presence of a peak on the 001 plane to the 002 plane in the X-ray diffraction pattern (for example, the 33rd in addition to Non-Patent Document 1). Summary of Petroleum and Petrochemical Discussion Meeting; Catalyst, 2001, 43, p158-160; Chemical Communications (UK), 2002, p1026-1027; Catalyst, 2002, 44, p468 -470; etc.). Then, the layer structure of the layered titanosilicate is converted into an MWW structure by firing the interlayer dehydration condensation of the crystal sheet to form a three-dimensional crystal structure. Specifically, this structural conversion can be confirmed by the disappearance of the 001 to 002 plane peaks in the X-ray diffraction pattern (see the above-mentioned documents).

  In order to separate the crystals (layered titanosilicate), for example, the reaction solution obtained by the second-stage hydrothermal synthesis reaction may be filtered, and the obtained filter residue may be washed as necessary. At this time, the conditions and method of filtration and washing are not particularly limited, and can be performed according to ordinary conditions and methods. For example, the washing may be performed by washing the filter residue with water until the pH of the washing solution is in the range of 4 to 10. Furthermore, the crystals separated as a filter residue can be dried as necessary. The drying conditions and method are not particularly limited, and can be performed according to ordinary conditions and methods. For example, the drying may be performed at 50 to 150 ° C. for about 1 to 24 hours. Further, when drying is performed using a spray dryer, it is advantageous in that it can be formed into particles having a particle diameter of about 1 to 1000 μm simultaneously with drying.

  Step (5) is a step of firing the crystal (layered titanosilicate) obtained in step (4). The firing conditions are not particularly limited, and may be heated at a temperature of about 200 to 700 ° C. for about 1 to 24 hours, for example.

  In addition, you may give an acid treatment to the crystal | crystallization (layered titanosilicate) obtained by the process (4) as needed, before using for baking. By performing acid treatment, boron introduced into the titanosilicate skeleton and titanium outside the skeleton can be removed, and the catalytic activity of the obtained titanosilicate can be improved.

  Examples of the acid that can be used for the acid treatment include inorganic acids such as nitric acid, sulfuric acid, carbonic acid, and phosphoric acid, and organic acids such as formic acid and acetic acid. Of these, nitric acid and sulfuric acid are particularly preferable. The amount of acid used is not particularly limited, and may be set as appropriate as long as boron introduced into the titanosilicate skeleton and titanium outside the skeleton can be sufficiently removed. The treatment temperature and treatment time for the acid treatment are not particularly limited and may be set as appropriate. In addition, when the acid treatment is performed, separation, washing, drying, and the like similar to the step (4) can be performed after the treatment.

  The titanosilicate obtained by the production method of the present invention is a crystalline titanosilicate having an MWW structure (hereinafter, the crystalline titanosilicate having an MWW structure may be referred to as “Ti-MWW”). MWW is one of the structure codes of zeolite defined by the International Zeolite Association (IZA). Specific examples of the compound having an MWW structure include MCM-22, SSZ-25, ITQ-1, ERB-1, and PSH-3.

  As used herein, titanosilicate includes titanium, silicon, and oxygen as elements constituting the skeleton, and the skeleton may be substantially composed of only titanium, silicon, and oxygen. In addition, elements other than titanium, silicon, and oxygen, such as boron, aluminum, gallium, iron, and chromium, may be included as elements constituting the skeleton.

  In the Ti-MWW obtained by the production method of the present invention, the atomic ratio of titanium to silicon (Ti / Si) is usually 0.005 to 0.1, preferably 0.01 or more. In addition, when this titanosilicate contains elements other than titanium, silicon, and oxygen, the atomic ratio of the contained element with respect to silicon is 0.05 or less normally, Preferably it is 0.02 or less. Moreover, oxygen can exist corresponding to the atomic ratio and oxidation number of each element other than oxygen. A typical composition of such titanosilicate can be represented by the following formula with silicon as the reference (= 1).

SiO ₂ xTiO ₂ yMO _{n / 2}
(In the formula, M represents at least one element other than silicon, titanium, and oxygen, n is an oxidation number of the element, x is 0.005 to 0.1, and y is 0 to 0.05. .)

  The content ratio (Ti content) of titanium contained in Ti-MWW obtained by the production method of the present invention in titanosilicate is usually 0.4% or more, preferably 1% or more.

  Thus, a titanosilicate having an MWW structure can be obtained. In the presence of this titanosilicate, the ammoximation reaction of the ketone with peroxide and ammonia allows the ketone to be ammoximeated at a high conversion rate while maintaining the catalyst life for a long time. Oxime can be produced at a rate. Such titanosilicate is expected to exhibit high activity over a long period of time as a catalyst in oxidation reactions such as epoxidation and oxime other than the above reaction.

Ti-MWW used as a catalyst may be used in the form of particles or pellets with or without a binder, or may be used by being supported on a carrier.
Ti-MWW used as a catalyst is preferably suspended in the liquid phase of the reaction mixture and present as a solid phase, and the ratio is usually about 0.1 to 10% by weight with respect to the liquid phase. . In addition, for the purpose of suppressing a decrease in the catalytic activity of Ti-MWW, silicon compounds other than titanosilicates such as silica gel, silicic acid, and crystalline silica may coexist.

  The ketone may be an aliphatic ketone, an alicyclic ketone, or an aromatic ketone, and two or more of them may be used as necessary. The ketone may be obtained by, for example, oxidation of alkane, may be obtained by oxidation (dehydrogenation) of secondary alcohol, or hydration and oxidation of alkene. It may be obtained by (dehydrogenation).

  Specific examples of the ketone include dialkyl ketones such as acetone, ethyl methyl ketone, and isobutyl methyl ketone; alkyl alkenyl ketones such as mesityl oxide; alkyl aryl ketones such as acetophenone; diaryl ketones such as benzophenone; Examples include cycloalkanones such as nonone, cyclohexanone, cyclooctanone and cyclododecanone; cycloalkenones such as cyclopentenone and cyclohexenone. Among these, cycloalkanone is preferable.

Specific examples of the peroxide include hydrogen peroxide, and organic peroxides such as t-butyl hydroperoxide, di-t-butyl peroxide, and cumene hydroperoxide. Among these, hydrogen peroxide is preferable in terms of reactivity.
Hydrogen peroxide is usually produced by the so-called anthraquinone method, and is generally marketed as an aqueous solution having a concentration of 10 to 70% by weight. Therefore, this aqueous hydrogen peroxide solution can be used. Hydrogen peroxide can also be produced by reacting hydrogen and oxygen in an organic solvent in the presence of a solid catalyst supporting metal palladium. An organic solvent solution of hydrogen peroxide obtained by separating the catalyst from the mixture can be used.

  The amount of the peroxide used is usually 0.5 to 3 moles, preferably 0.5 to 1.5 moles per mole of ketone. Examples of the peroxide include phosphates such as sodium phosphate, polyphosphates such as sodium pyrophosphate and sodium tripolyphosphate, pyrophosphate, ascorbic acid, ethylenediaminetetraacetic acid, nitrotriacetic acid, aminotriacetic acid. Diethylenetriaminepentaacetic acid or the like may be added.

  The ammonia may be a gaseous one, a liquid one, or a solution of water or an organic solvent.

  The amount of ammonia used is preferably adjusted so that the ammonia concentration in the liquid phase of the reaction mixture is 1% by weight or more. Thus, by setting the ammonia concentration in the liquid phase of the reaction mixture to 1% by weight or more, it is possible to increase the conversion rate of the raw material ketone and the selectivity of the target oxime, and thus the yield of the target oxime. The rate can be increased. The ammonia concentration in the liquid phase of the reaction mixture is preferably 1.5% by weight or more, while the upper limit is usually 10% by weight or less, preferably 5% by weight or less. It is good. In addition, the standard of the usage-amount of ammonia is 1 mol or more normally with respect to 1 mol of ketone, Preferably it is 1.5 mol or more.

  The ammoximation reaction can also be performed in a solvent. Examples of the reaction solvent at this time include aromatic compounds such as benzene and toluene, methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, s-butyl alcohol, t-butyl alcohol, t -Alcohols such as amyl alcohol, water and the like. Among these, alcohol and water are preferable, and a mixed solvent of alcohol and water is more preferable in terms of reactivity.

  The ammoximation reaction may be performed batchwise or continuously. In particular, it is desirable from the viewpoint of productivity and operability that the reaction system is continuously extracted by supplying a reaction mixture from the reaction system while supplying ketone, peroxide and ammonia into the reaction system.

  The batch reaction may be performed, for example, by adding a ketone, ammonia, a catalyst, and a solvent to a reactor, and supplying a peroxide to the reactor with stirring, or by adding a ketone, a catalyst, and a solvent to the reactor. It may be carried out by supplying peroxide and ammonia into this under stirring, or by adding a catalyst and solvent into the reactor and supplying ketone, peroxide and ammonia into this under stirring. You may go.

In the continuous reaction, for example, a reaction mixture in which a catalyst is suspended is present in the reactor, and a ketone, peroxide, ammonia and a solvent are supplied to the reaction mixture through a filter or the like from the reactor. It can be suitably carried out by extracting the liquid phase of the reaction mixture.
In either case of batch type or continuous type, the reactor is preferably glass-lined or stainless steel from the viewpoint of preventing decomposition of peroxide.

  The reaction temperature of the ammoximation reaction is usually 50 to 120 ° C, preferably 70 to 100 ° C. The reaction pressure may be normal pressure, but in order to easily dissolve ammonia in the liquid phase of the reaction mixture, the absolute pressure is usually 0.2 to 1 MPa, preferably 0.2 to 0.5 MPa. It is preferable to carry out the reaction. When performed under pressure, the pressure may be adjusted using an inert gas such as nitrogen or helium.

  The post-treatment operation for recovering the oxime from the reaction mixture obtained by the ammoximation reaction is not particularly limited and may be appropriately performed according to a normal method. For example, after separating the catalyst from the reaction mixture by filtration or decantation, the oxime can be separated and recovered by subjecting the liquid phase to distillation.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited by this Example.
Here, the Ti content (content ratio of the total amount of titanium in Ti-MWW) of the titanosilicate (Ti-MWW) obtained in each Example and Comparative Example was measured by ICP analysis. In addition, analysis of the liquid phase in the production of oxime was performed by gas chromatography.

  The catalyst life of Ti-MWW in oxime production was judged based on the oxygen concentration in the autoclave. In other words, when hydrogen peroxide is used as a peroxide, if the catalytic activity decreases, the amount of oxygen generated due to thermal decomposition of hydrogen peroxide increases, and the oxygen concentration in the system increases rapidly. It can be said that the longer the reaction time until the oxygen concentration rapidly increases, the longer the catalyst life.

<ICP analysis>
Weigh the sample in a platinum dish, add hydrofluoric acid and nitric acid, heat and evaporate to dryness, add sodium carbonate and boric acid, melt with a burner, and add diluted hydrochloric acid to the resulting melt. In addition, the mixture was heated to obtain a test solution as a constant volume. The Ti in this test solution was subjected to ICP analysis with an ICP emission analyzer (“SPS4000” manufactured by Seiko Denshi Kogyo Co., Ltd.), and the Ti content in the sample was determined.

(Reference Example-Preparation of seed crystal)
In a beaker, 445.87 g of pure water, 77.53 g of piperidine, and 11.07 g of tetra-n-butyl orthotitanate were added and stirred in an air atmosphere until it was uniform at room temperature, and then 53.93 g of boric acid was added to be uniform. Stir until. After adding 39.20 g of fumed silica (“CAB-O-SIL M-7D” manufactured by CABOT) to the obtained aqueous solution and stirring at room temperature for 1 hour, the mixture was transferred to an autoclave and the autoclave was sealed. While heating the autoclave with a heater while stirring this mixed liquid, the temperature was raised from room temperature to 170 ° C. over 5 hours, and then heated at the same temperature for 7.5 days for hydrothermal synthesis. The obtained suspension was filtered, and the residue was washed until the pH of the washing solution became 10 or less, and then dried at 110 ° C. for 16 hours to obtain 44.40 g of a white powder. 30 g of this white powder was heated to reflux in 900 g of 2M nitric acid for 16 hours and then filtered, and the residue was washed until the pH of the washing solution reached 4 or higher. The obtained white powder was dried and then calcined at 530 ° C. for 10 hours to obtain Ti-MWW having a Ti content of 2.1%.

Example 1
[Manufacture of titanosilicate]
A beaker was charged with 343 g of pure water, 78 g of piperidine, and 54 g of boric acid, and the mixture was stirred in an air atmosphere at room temperature until uniform. After adding 39 g of fumed silica (“CAB-O-SIL M-7D” manufactured by CABOT) to the obtained aqueous solution and stirring for 1 hour, 0.4 g of Ti-MWW obtained in the reference example was added as a seed crystal. It was. The obtained mixed liquid was transferred to an autoclave, the autoclave was sealed, and this mixed liquid was heated to 170 ° C. with stirring, and then heated at the same temperature for 5 days to carry out a first-stage hydrothermal synthesis reaction.

  Next, after heating is temporarily interrupted and the autoclave is cooled to room temperature, 9 g of tetra-n-butyl orthotitanate, 19 g of piperidine and 114 g of pure water are mixed in advance with the reaction solution in the autoclave at room temperature until uniform. The solution stirred for 1 hour was added. Next, the autoclave was sealed again, and the temperature was raised to 170 ° C. as in the first stage hydrothermal synthesis reaction, followed by heating at the same temperature for 2 days to perform the second stage hydrothermal synthesis reaction.

  The obtained suspension was filtered, and the residue was washed until the pH of the wash became 10 or less, and then dried at 110 ° C. for 16 hours to obtain 46 g of a white powder. 30 g of this white powder was heated and refluxed in 900 g of 2M nitric acid for 8 hours and then filtered, and the residue was washed until the pH of the washing solution became 4 or higher. The obtained white powder was dried at 110 ° C. and then calcined at 530 ° C. for 10 hours to obtain Ti-MWW (1) having a Ti content of 1.2%.

[Oxime production]
A 1 liter autoclave was used as a reactor, in which cyclohexanone was 19.63 g / hour, hydrous t-butyl alcohol (water 12 wt%) was 34 g / hour, and 50 wt% hydrogen peroxide was 15.64 g. By pulling out the liquid phase of the reaction mixture from the reactor through a filter while feeding at a rate of / hour and supplying ammonia to be present at a concentration of 2% by weight in the liquid phase of the reaction mixture, The continuous reaction was performed under the conditions of a temperature of 95 ° C., a pressure of 0.35 MPa (absolute pressure), and a residence time of 6 hours. During this period, the Ti-MWW (1) was present in the reaction mixture in the reactor at a ratio of 0.2 wt% with respect to the liquid phase.

  As a result of analyzing the liquid phase extracted 5.5 hours after the start of the reaction, the conversion of cyclohexanone was 99.3%, the selectivity of cyclohexanone oxime was 99.5%, and the yield of cyclohexanone oxime was 98.9%. Met. As a result of analyzing the liquid phase extracted after 129 hours from the start of the reaction, the conversion of cyclohexanone was 99.9%, the selectivity of cyclohexanone oxime was 99.5%, and the yield of cyclohexanone oxime was 99.4%. Met. Further, when the reaction was continued, the oxygen concentration in the autoclave increased rapidly after 148 hours from the start of the reaction, so the reaction was terminated at this point.

(Example 2)
[Manufacture of titanosilicate]
Ti-MWW (2) having a Ti content of 1.8% was obtained in the same manner as in Example 1 except that the amount of tetra-n-butyl orthotitanate was changed to 11 g.

[Oxime production]
A continuous reaction was carried out under the same conditions as in Example 1 except that the above Ti-MWW (2) was used instead of Ti-MWW (1).
As a result of analyzing the liquid phase extracted 5.5 hours after the start of the reaction, the conversion of cyclohexanone was 99.6%, the selectivity of cyclohexanone oxime was 99.7%, and the yield of cyclohexanone oxime was 99.3%. Met. As a result of analyzing the liquid phase extracted 68 hours after the start of the reaction, the conversion of cyclohexanone was 99.9%, the selectivity of cyclohexanone oxime was 99.7%, and the yield of cyclohexanone oxime was 99.6%. Met. Furthermore, when the reaction was continued, the reaction was terminated because the oxygen concentration in the autoclave rapidly increased 136 hours after the start of the reaction.

(Example 3)
[Manufacture of titanosilicate]
Ti-MWW (3) having a Ti content of 2.6% was obtained in the same manner as in Example 1 except that the amount of tetra-n-butyl orthotitanate was changed to 13 g.

[Oxime production]
A continuous reaction was carried out under the same conditions as in Example 1 except that the above Ti-MWW (3) was used instead of Ti-MWW (1).
As a result of analyzing the liquid phase extracted 5.5 hours after the start of the reaction, the conversion of cyclohexanone was 99.5%, the selectivity of cyclohexanone oxime was 99.7%, and the yield of cyclohexanone oxime was 99.2%. Met. As a result of analyzing the liquid phase extracted after 142 hours from the start of the reaction, the conversion of cyclohexanone was 99.9%, the selectivity of cyclohexanone oxime was 99.6%, and the yield of cyclohexanone oxime was 99.5%. Met. Further, when the reaction was continued, the reaction was terminated because the oxygen concentration in the autoclave rapidly increased 154 hours after the start of the reaction.

(Comparative Example 1)
[Manufacture of titanosilicate]
In a beaker, 446 g of pure water, 77 g of piperidine, and 9 g of tetra-n-butyl orthotitanate were added and stirred in an air atmosphere until uniform at room temperature, and then 54 g of boric acid was added and stirred until uniform at room temperature. . After adding 40 g of fumed silica (“CAB-O-SIL M-7D” manufactured by CABOT) to the obtained aqueous solution and stirring for 1 hour, 0.5 g of Ti-MWW obtained in the reference example was added as a seed crystal. It was. The obtained mixed solution was transferred to an autoclave and the autoclave was sealed. Then, the mixed solution was heated to 170 ° C. with stirring and then heated at the same temperature for 7 days to perform a hydrothermal synthesis reaction.

  The obtained suspension was filtered, and the residue was washed until the pH of the washing solution became 10 or less, and then dried at 110 ° C. for 16 hours to obtain 77 g of a white powder. 30 g of this white powder was heated to reflux in 900 g of 2M nitric acid for 16 hours and then filtered, and the residue was washed until the pH of the washing solution reached 4 or higher. The obtained white powder was dried at 110 ° C. and then calcined at 530 ° C. for 10 hours to obtain Ti-MWW (C1) having a Ti content of 1.1%.

[Oxime production]
A continuous reaction was performed under the same conditions as in Example 1 except that the above Ti-MWW (C1) was used instead of Ti-MWW (1).
As a result of analyzing the liquid phase extracted 5.5 hours after the start of the reaction, the conversion of cyclohexanone was 99.2%, the selectivity of cyclohexanone oxime was 99.5%, and the yield of cyclohexanone oxime was 98.7%. Met. As a result of analyzing the liquid phase extracted 127 hours after the start of the reaction, the conversion of cyclohexanone was 95.9%, the selectivity of cyclohexanone oxime was 98.1%, and the yield of cyclohexanone oxime was 94.1%. Met. Furthermore, when the reaction was continued, 131 hours after the start of the reaction, the oxygen concentration in the autoclave rapidly increased, so the reaction was terminated.

(Comparative Example 2)
[Manufacture of titanosilicate]
Ti-MWW (C2) having a Ti content of 2.1% was obtained in the same manner as in Comparative Example 1 except that the amount of tetra-n-butyl orthotitanate was changed to 11 g.

[Oxime production]
A continuous reaction was performed under the same conditions as in Example 1 except that the above Ti-MWW (C2) was used instead of Ti-MWW (1).
As a result of analyzing the liquid phase extracted 5.5 hours after the start of the reaction, the conversion of cyclohexanone was 99.3%, the selectivity of cyclohexanone oxime was 99.5%, and the yield of cyclohexanone oxime was 98.7%. Met. As a result of analyzing the liquid phase extracted after 117 hours from the start of the reaction, the conversion of cyclohexanone was 99.1%, the selectivity of cyclohexanone oxime was 99.3%, and the yield of cyclohexanone oxime was 98.3%. Met. Furthermore, when the reaction was continued, 126 hours after the start of the reaction, the oxygen concentration in the autoclave rapidly increased, so the reaction was terminated.

(Comparative Example 3)
[Manufacture of titanosilicate]
Ti-MWW (C3) having a Ti content of 2.4% was obtained in the same manner as in Comparative Example 1 except that the amount of tetra-n-butyl orthotitanate was changed to 13 g.

[Oxime production]
A continuous reaction was performed under the same conditions as in Example 1 except that the above Ti-MWW (C3) was used instead of Ti-MWW (1).
As a result of analyzing the liquid phase extracted 5.5 hours after the start of the reaction, the conversion of cyclohexanone was 99.4%, the selectivity of cyclohexanone oxime was 99.6%, and the yield of cyclohexanone oxime was 99.0%. Met. As a result of analyzing the liquid phase extracted 106 hours after the start of the reaction, the conversion of cyclohexanone was 99.3%, the selectivity of cyclohexanone oxime was 99.4%, and the yield of cyclohexanone oxime was 98.7%. Met. Furthermore, when the reaction was continued, the reaction was terminated because the oxygen concentration in the autoclave rapidly increased 116 hours after the start of the reaction.

Claims (7)

The manufacturing method of the titanosilicate which has the MWW structure characterized by including the following processes (1) -process (5).
Step (1): Step of mixing silicon compound, boron compound, water and structure directing agent Step (2): Step of heat-treating the mixture obtained in Step (1) to obtain a suspension Step (3): Step Step (4) for mixing the suspension obtained in (2) and the titanium compound: Step (5): Step for separating the crystals formed after heat-treating the mixture obtained in Step (3) The step of firing the crystal obtained in (4)   The manufacturing method of the titanosilicate of Claim 1 whose usage-amount of the said titanium compound is 0.05-0.10 mol with respect to 1 mol of silicon in the said silicon compound on the basis of titanium in this titanium compound. .   The manufacturing method of the titanosilicate of Claim 1 or 2 which mixes in a process (3) at 50 degrees C or less.   A method for producing an oxime, wherein a ketone is subjected to an ammoximation reaction with a peroxide and ammonia in the presence of a titanosilicate having an MWW structure obtained by the method for producing a titanosilicate according to any one of claims 1 to 3. .   The method for producing an oxime according to claim 4, wherein the ammoximation reaction is carried out in a mixed solvent of alcohol and water.   The method for producing an oxime according to claim 4 or 5, wherein the peroxide is hydrogen peroxide.   The method for producing an oxime according to any one of claims 4 to 6, wherein the ketone is a cycloalkanone.