JPH0380779B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a novel method for producing alcohol by a hydration reaction of olefin.
More specifically, at least one kind of organic compound selected from lower alkyl urea and lower alkyl thiourea is coexisted with hydrothermal synthesis, and the organic compound is further removed in the liquid phase using an oxidizing agent, and zeolite is used as a catalyst. The present invention relates to a method for producing alcohol by a hydration reaction of olefin, characterized by: (Prior Art) Conventionally, indirect or direct hydration reactions using mineral acids, particularly sulfuric acid, have been known as methods for producing alcohols by hydration reactions of olefins. Also,
Another method using aromatic sulfonic acid as a homogeneous catalyst (Japanese Patent Publication No. 8104/1986,
16123) and a method using heteropolyacids such as phosphotungstic acid and phosphomolybdic acid (Japanese Patent Application Laid-open No. 1987-9746). However, these homogeneous catalysts have the disadvantage that separation and recovery from the reactants, especially the aqueous layer, is complicated and consumes a large amount of energy. As a method for improving these drawbacks, a method using a solid catalyst, for example a method using an ion exchange resin, has been proposed (Japanese Patent Publication No. 38-15619, Japanese Patent Publication No. 44-26656). However, these ion exchange resins have problems such as pulverization of the resin due to mechanical collapse and a decrease in catalytic activity due to insufficient heat resistance, etc., and the drawback is that stable activity cannot be maintained for a long time. There is. Furthermore, as a method using a solid catalyst, there is a method using crystalline aluminosilicate. Crystalline aluminosilicate is insoluble in water, has excellent mechanical strength and heat resistance, and is expected to be used as an industrial catalyst, and the following method has been proposed. In other words, a method for hydrating olefins using dealkalized mordenite, clinobutyrolite, or fauziasite zeolite as a catalyst (Japanese Patent Publication No. 45323/1983), a method for hydration of olefins using dealkalized mordenite, clinobutyrolite, or fauziasite zeolite (Japanese Patent Publication No. 47-45323), a method for hydrating calcium cations, chromium cations, and rare earth element cations. Hydration method of olefins using Y-type zeolite containing one or more of ions and chromium oxide as a catalyst (Japanese Patent Publication No. 1983-
15485 Publication), ZSM-5, etc., all or part of the ion-exchangeable cations of certain crystalline aluminosilicate published by Mobil Corporation are replaced by hydrogen, groups of the periodic table, group or earth, diluent element ions. A method for hydrating olefins using a catalyst substituted with A method for hydrating olefins using a catalyst in which the moieties are exchanged with hydrogen, groups of groups of the periodic law, earth, or rare earth element ions (Japanese Patent Application Laid-open No. 124723/1983), in which the silica/alumina ratio is 20 or more. There is a method for hydrating cyclic olefins using crystalline aluminosilicate as a catalyst (Japanese Patent Application Laid-open No. 194828/1983). Furthermore, a method for hydrating a cyclic olefin using as a catalyst a crystalline aluminosilicate in which the ratio of outer surface acid sites to total acid sites is 0.07 or more (Japanese Patent Application Laid-open No. 104028/1983), a silica source, an alumina source,
A method for hydrating a cyclic olefin using as a catalyst a crystalline aluminosilicate synthesized by heating an aqueous mixture containing an alkali metal source in the presence of at least one compound selected from lower alkyl ureas and lower alkyl thioureas. Tokukai Akira
61-180735), etc. (Problems to be Solved by the Invention) However, with these methods, industrially sufficient activity cannot be obtained, and in order to obtain an industrially satisfactory reaction rate, it is necessary to increase the reaction temperature. However, the hydration reaction of olefin is an exothermic reaction, and the ratio of alcohol to olefin at equilibrium composition decreases as the temperature increases. Therefore, an increase in the reaction temperature brings about a decrease in the concentration of the product alcohol, and as a result, a large amount of cost is required to separate and recover the raw material olefin or water and the product alcohol. On the other hand, an increase in reaction temperature increases not only the hydration reaction rate of olefin but also the conversion rate to by-products through reactions such as isomerization, and as a result, the selectivity of the intended reaction decreases. While conventional zeolites exhibit only low activity, zeolites synthesized in the coexistence of lower alkyl ureas can have higher activity, as reported in JP-A-Sho.
Although it is described in Japanese Patent No. 61-180735, a catalyst having even higher activity is desired. (Means for Solving the Problems) As a result of extensive research in order to solve the above problems, the present inventors have found that coexistence of at least one organic compound selected from lower alkyl ureas and lower alkyl thioureas. By using zeolite as a catalyst, which has been synthesized sewage thermally and further removed the organic compound with an oxidizing agent in the liquid phase, it exhibits significantly higher activity in the olefin hydration reaction than conventional methods, and It was discovered that the reactivity lasts for a long time, and the present invention was completed. That is, the present invention involves hydrothermal synthesis in the coexistence of at least one organic compound selected from lower alkyl urea and lower alkyl thiourea when producing alcohol by hydration reaction of olefin,
Furthermore, the present invention relates to a method for producing alcohol by a hydration reaction of olefin, characterized in that a zeolite from which the organic compound has been removed in a liquid phase with an oxidizing agent is used as a catalyst. The zeolite treated as shown in the present invention is
It shows significantly improved activity for the hydration reaction of olefins and gives alcohols in high yields. That is, the activity is significantly improved compared to the example described in JP-A-64-180735, which uses a zeolite synthesized in the coexistence of a lower alkyl urea. The reason for this improvement in activity is that in the present invention, the organic compounds in the zeolite are removed using an oxidizing agent in the liquid phase, and the zeolite thus obtained is subjected to a hydration reaction. It depends. According to JP-A-61-180735, the organic compounds in the zeolite are removed by, for example, calcination at 550° C. for 5 hours as shown in the examples. It is unclear why the activity in the hydration reaction of olefin is improved by this method of removing the organic substances in the zeolite, but the organic compounds in the zeolite synthesized in the coexistence of lower alkyl ureas, etc. It is oxidized by an oxidizing agent and easily elutes into the liquid phase. In fact, as shown in the examples, analysis of zeolite that has undergone such treatment reveals that organic compounds are almost completely removed. In addition, in this removal operation using an oxidizing agent in the liquid phase, phenomena such as the collapse of acid sites in zeolite, which would be expected when calcined at high temperatures, were not observed at all, which is the cause of high activity. I think so. In addition, new active sites may be formed by such treatment, that is, contact between the oxidizing agent and the zeolite. Furthermore, according to the study results of the present inventors, it was found that such an effect was first seen when using the zeolite synthesized hydrothermally in the coexistence of the lower alkyl urea of the present invention. As a method for synthesizing zeolite in the coexistence of an organic compound, zeolite synthesized using a quaternary ammonium salt such as tetrapropylammonium salt, which is the most typical organic compound, as an organic compound is synthesized using an oxidizing agent as described in the present invention. When treated with zeolite, the resulting zeolite shows no improvement in activity in the olefin hydration reaction. That is, compared to the zeolite containing the above-mentioned organic substances treated by calcination, the hydration activity is not improved, and in some cases, the hydration activity is only significantly decreased. There are various possible reasons for this, but for example, it is thought that quaternary ammonium salts such as tetrapropylammonium salts are difficult to remove from the zeolite by the treatment of the present invention. In fact, analysis of the zeolite treated in this manner revealed that a large amount of carbon or nitrogen components remained. That is, the method of the present invention has become possible for the first time for zeolites synthesized using lower alkyl ureas. The method for synthesizing the zeolite used in the present invention is described in Japanese Patent Application No. 59-188165, and in order to explain the substance and its preparation method, the main points thereof are shown below. The zeolite used in the present invention has a silica source,
It is obtained by heating an aqueous mixture containing an alumina source and an alkali metal source in the coexistence of at least one compound selected from lower alkyl ureas and lower alkyl thioureas. As the silica source, alumina source, and alkali metal source used in the synthesis of the zeolite used in the present invention, those normally used in the synthesis of zeolite can be used. As the silica source, sodium silicate, water glass, silica gel, silicic anhydride, etc. can be used. As the alumina source, sodium aluminate, aluminum sulfate, aluminum nitrate, aluminum hydroxide, alumina, etc. can be used. As the alkali metal source, sodium hydroxide, sodium silicate, water glass, sodium aluminate, potassium hydroxide, etc. are used, and sodium compounds are preferred. In the present invention, the lower alkyl urea used in the synthesis of crystalline aluminosilicate is

It is represented by [Formula], and 1 or 2 of R ₁ , R ₂ , and R ₃ are an alkyl group having 4 or less carbon atoms,
It is a compound in which the remainder consists of hydrogen atoms. Examples of preferred lower alkyl ureas include methyl urea,
1,3-dimethylurea, 1,1-dimethylurea,
Ethyl urea, 1,1-diethyl urea, 1,3-diethyl urea, n-propylurea, i-propylurea, 1-methyl・1-ethyl urea, 1-methyl・
Examples include 3-ethyl urea. In the present invention, the lower alkylthiourea used in the synthesis of zeolite is

It is represented by [Formula], and 1 or 2 of R ₁ , R ₂ , and R ₃ are an alkyl group having 4 or less carbon atoms,
It is a compound in which the remainder consists of hydrogen. Examples of preferred lower alkylthioureas include methylthiourea, 1,3-dimethylthiourea, 1,1-dimethylthiourea, ethylthiourea, 1,1-diethylthiourea, 1,3-diethylthiourea, n-propiothiourea, i-propylthio Urea, 1-methyl. Examples include 1-ethylthiourea, 1-methyl/3-ethylthiourea, and the like. In the present invention, the composition of the silica source, alumina source, alkali metal source, water, and at least one compound selected from lower alkyl urea and lower alkyl thiourea in the aqueous mixture used for zeolite synthesis is expressed in molar ratio. The following range is appropriate. [However, the silica source is expressed in terms of silica (SiO ₂ ) gram moles, the alumina source is expressed in terms of alumina (AlO ₃ ) gram moles, and the alkali metal source is expressed in terms of alkali metal gram atoms. ] Silica source/Alumina source = 10-1000 Water/Silica source = 10-100 Alkali metal source/Silica source = 0.001-10 A/Silica source = 0.01-10 (A is selected from lower alkyl urea and lower alkyl thiourea) (Represents the sum of gram moles of at least one compound.) A more preferable composition range is the following range. Silica source/Alumina source = 15-200 Water/Silica source = 15-50 Alkali metal source/Silica source = 0.05-1 A/Silica source = 0.1-5 Lower alkyl urea and lower alkyl thio in the synthesis of zeolite used in the present invention An aqueous mixture (hereinafter referred to as aqueous mixture) containing a silica source, an alumina source, and an alkali metal source in which at least one compound selected from urea (hereinafter referred to as lower alkyl urea) coexists is prepared as follows. For example: Water containing an alumina source and a lower alkyl urea are mixed with water containing a silica source while stirring. If necessary, adjust the hydrogen ion concentration by adding acid or alkali. Hydrogen ion concentration PH
The preferred range of is 10 to 13. The alkali metal source is added together with the silica source and/or the alumina source, or when adjusting the hydrogen ion concentration. The aqueous mixture is heated at 90 to 250℃ in a pressure-resistant container.
Preferably heated to 100 to 180 degrees. Heating is preferably carried out while stirring. The heating time depends on the heating temperature; the higher the heating temperature, the shorter the heating time, and the lower the heating temperature, the longer the heating time.
It is preferable to heat for 10 to 200 hours, but heating for more than 200 hours is also acceptable. By the above method, fine and highly crystalline zeolite can be easily synthesized. When observed using a scanning electron microscope, fine zeolite is mainly columnar or hexagonal plate-shaped crystals, and in the case of columnar crystals, the average maximum diameter of the cross section, and in the case of hexagonal plate-shaped crystals, the short axis It is a zeolite with an average size of less than 1 micron. However, depending on the zeolite adjustment conditions,
Its shape may change. To synthesize fine zeolite, heating with strong stirring is desirable. To synthesize fine zeolite, the first step is 100 to 140℃, the second step is 155 to 180℃.
More preferred is two-step heating. In the case of two-stage heating, the first stage heating time is preferably 30 to 140 hours. Table 1 shows the X-ray diffraction pattern of the zeolite synthesized by the method of the present invention.

[Table] In the synthesis of the crystalline aluminosilicate used in the present invention, if desired, titanium, vanadium,
Oxide sources such as chromium, manganese, iron, zinc, potassium, boron, etc. can be added to the aqueous mixture with or in place of the alumina source to synthesize these foreign element-containing zeolites. Zeolite synthesized by the method shown in the example above is
The present invention is characterized in that it is treated with an oxidizing agent in a liquid phase without firing at a high temperature. Examples of the oxidizing agent used in the oxidizing treatment of zeolite in the present invention include compounds having an oxygen-oxygen-heavy bond in the molecule, specifically hydrogen peroxide, ozone, persulfuric acid, and tertiary butyl hydroperoxide. Hydroperoxides such as, organic peracids such as peracetic acid and perpropionic acid, and salts such as chlorates, hypochlorites, permanganates, and dichromates can be used. However, hydrogen peroxide and ozone are particularly preferred. Even if hydrogen peroxide or ozone is added in excess, it has the advantage that it will decompose by itself and will not remain in the liquid if left for a while after addition. The method of removing the organic compound from the zeolite synthesized using a lower alkyl urea or the like in the method of the present invention using the above-mentioned oxidizing agent is not particularly limited, but is exemplified below. Zeolite synthesized using organic compounds is obtained in a slurry state after hydrothermal synthesis. In addition to the crystallized zeolite, this slurry usually contains uncrystallized excess gel-like substances such as silica or alumina, and excess organic compounds. Therefore, when these substances are contained, if the oxidizing agent and mineral acid are directly brought into contact using the method of the present invention, for example, if there is an excess of organic compounds, a larger amount is added to decompose them. This would consume oxidizing agent and be too expensive. In addition, when a gel-like substance is contained, when the zeolite solid is separated from the slurry, the gel-like substance is obtained in the form of being included in the zeolite as it is. Therefore, it is desirable to wash the material with water before contacting it with the oxidizing agent. Although the washed zeolite is slurried in water and oxidized, there is no particular restriction on the concentration of the oxidizing agent. When the concentration of oxidizing agent is high,
Since the oxidation rate of organic matter becomes faster, the contact time with zeolite can be relatively shortened, but if it is too concentrated, heat will be generated during the oxidation reaction of organic matter, causing the system temperature to rise too much. If you pull it out, it may cause bumping, so you need to be careful.
Furthermore, the amount of self-decomposition increases, the effective utilization rate of the oxidizing agent decreases, and the amount of oxidizing agent used increases. on the other hand,
If the concentration of oxidizing agent is extremely dilute, longer contact times are required. Generally speaking, the concentration of the oxidizing agent is 0.01 to 50% by weight, preferably 0.1 to 20% by weight.
There is a method in which an oxidizing agent is gradually added to a zeolite slurry to gradually and continuously oxidize organic compounds. After removing organic compounds such as lower alkyl ureas by the method described above, it is desirable to perform ion exchange directly with or without washing with water. The zeolite is treated with protons, alkaline earth elements such as Mg, Ca, and Sr, rare earth elements such as Ca and Ce, Fe, Co, Ni,
Group elements such as Ru, Pd, Pt, or Ti, Zr,
Ion exchange can be performed with elements such as Hf, Cr, Mo, W, and Th. Particularly preferred is exchange with protons. The exchange into protons can be carried out by contacting with a mineral acid such as sulfuric acid, nitric acid, hydrochloric acid, or phosphoric acid, or by the conventional method of contacting with an ammonia compound such as ammonia chloride or ammonium nitrate, followed by firing at a relatively low temperature. can also be used. Desirably, it is a method of contacting with a mineral acid such as nitric acid. When mineral acids are used, there is no need for special calcination after contact with the mineral acids; all that is required is washing with water to remove excess mineral acids, and everything from zeolite synthesis to ion exchange can be handled in slurry form. There are merits. This effect is particularly great when subjected to a hydration reaction as in the present invention. In addition, when removing organic compounds with an oxidizing agent,
It is also possible to carry out oxidation and ion exchange simultaneously in a mineral acid aqueous solution, which can be said to be a more preferable form of use. That is, treatment with an oxidizing agent in the presence of a mineral acid greatly improves the oxidizing ability of the oxidizing agent, and suppresses self-decomposition of the oxidizing agent.
As a result, the oxidation of organic compounds is promoted, and the removal efficiency of organic compounds is greatly increased. In general, the concentration of mineral acid should be sufficient for ion exchange, but usually 0.1 to 10N,
Preferably it is 0.5 to 3 normal. If the concentration is too high, it may destroy the crystallinity of the zeolite, so care must be taken. There is no particular restriction on the temperature at which the zeolite is brought into contact with the oxidizing agent and/or the ion exchanger, but it is preferably between room temperature and about 100°C. Also, there is no particular limit to the contact time, but from 0.1 to
100 hours, preferably 1 to 10 hours. Excess oxidizing agents and/or mineral acids can be easily removed after contact by settling the zeolite and removing the supernatant, or by concentrating it by normal centrifugal dehydration or filtration, and then by adding water. It is possible to exclude The zeolite thus produced may be used in the reaction system as it is, or it can be used after drying or the like. In particular, in the case of a reaction system in which the hydration reaction is carried out in a slurry state in which zeolite is suspended in water, removal using an oxidizing agent such as lower alkyl urea is carried out in the slurry state in water as in the present invention, and further, Since ion exchange is also handled as a slurry, the entire process from the crystallization stage is handled as a slurry, eliminating the need for equipment for calcination as in conventional technology, making the equipment simpler. The industrial effects are significant. It is also effective to remove some alumina from the zeolite used in the present invention before use. However, it is not preferable that the crystal structure of the zeolite itself changes due to this operation, and it is preferable that the strength can be stably maintained. The zeolite used in the present invention does not particularly specify the molar ratio of silica and alumina, but
The molar ratio of silica and alumina is 10 or more, and even 20
The above is preferable. When the molar ratio of silica to alumina is high, the acid strength of the acid sites that are active sites for hydration reactions increases, but on the other hand, the amount of acid sites decreases significantly. Therefore, a material with a molar ratio of silica to alumina of 300 or less, and even 100 or less is usually used. The zeolite used in the present invention is not particularly limited in the ratio of the outer surface acid sites to the total acid sites. However, the ratio of the outer surface acid sites to the total acid sites is also an indicator of the particle size of the zeolite. In order to effectively utilize internal acid sites, it is necessary to facilitate diffusion, and for this purpose it is desirable to make the particles fine. Therefore, the zeolite used in the present invention is one in which the ratio of the outer surface acid sites to the total acid sites is relatively large, preferably one in which the ratio of the outer surface acid sites to the total acid sites is 0.01 or more. More preferably it is 0.05 or more, particularly preferably 0.1 or more. In this reaction, the catalyst may be used in any form, including powder, granules, and molded bodies having a specific shape. Furthermore, when a molded body is used, alumina, silica, titania, etc. can also be used as a carrier or binder. The olefin used in the present invention is preferably an olefin having a linear or branched structure having 2 to 12 carbon atoms and a cyclic olefin. Examples of olefins include ethylene, propylene, 1-
Butene, 2-butene, isobutene, pentenes,
Hexenes, heptenes, octenes, cyclobutenes, cyclopentene, methylcyclopentenes, cyclohexene, methylcyclohexenes,
These include cyclooctene and cyclododecene. In particular, it is effective for hydrating cyclic olefins, which generally have a slow hydration reaction rate and a low equilibrium alcohol concentration. As for the reaction mode, commonly used methods such as a fluidized bed method, a stirring batch method, or a continuous method are used. Regarding the reaction temperature, a low temperature is advantageous from the viewpoint of the equilibrium of the olefin hydration reaction and from the viewpoint of increasing side reactions, etc., but a high temperature is advantageous from the viewpoint of the reaction rate. , the reaction temperature varies depending on the olefin used, but is usually 30
A range of ~300°C is used, preferably 50-250°C.
℃, particularly preferably in the range of 60 to 200℃. Further, the reaction pressure is not particularly limited, and the olefin and water may exist in a gas phase or a liquid phase. In particular, when water becomes a liquid phase, as mentioned above, the vicinity of the active site of the catalyst is generally covered with water, reducing the rate of the desired reaction, so this reaction is particularly effective in that case. show. The molar ratio of the raw materials olefin to water can be varied over a wide range, and also varies depending on whether the reaction is carried out continuously or batchwise. However, when olefin or water is in large excess compared to other raw materials, the reaction rate decreases and is not practical. Therefore, in the present invention, the molar ratio of olefin to water is 0.01 when the process is carried out batchwise, for example.
-100 is preferable, and 0.03-10 is especially preferable. When this reaction is carried out batchwise, the weight ratio of olefin to catalyst is preferably 0.005 to 100, particularly 0.05 to 100.
10 is preferred. Further, the reaction time is preferably 3 to 300 minutes, particularly preferably 10 to 180 minutes. In addition to olefin and water, which are reaction raw materials,
Inert gas such as nitrogen, hydrogen, helium, argon, carbon dioxide, etc., or aliphatic saturated hydrocarbons, aromatic hydrocarbons, oxygen-containing organic compounds, sulfur-containing organic compounds, halogen-containing organic compounds, etc. are present in the reaction system. Good too. (Effects of the Invention) The present invention achieves a hydration reaction of olefin by performing hydrothermal synthesis in the coexistence of at least one organic compound selected from lower alkyl urea and lower alkyl thiourea, and removing the organic compound with an oxidizing agent. This made it possible to provide an extremely highly active catalyst. (Example) Hereinafter, the present invention will be specifically described by showing Examples and Comparative Examples. Example 1 Catalyst preparation method 290g of sodium silicate (water glass No. 3) and 140g of water
(Liquid A). 20.8 g of aluminum sulfate and 7.0 g of sulfuric acid were dissolved in 80 g of water (solution B). 1,3-
34 g of dimethylurea was dissolved in 160 g of water (liquid C).
While stirring liquid A using a homogenizer,
Mixed with liquids B and C. The resulting gel-like aqueous mixture was placed in an autoclave 1 and heated at 160℃ for 24 hours.
Heat with stirring for an hour. The produced zeolite was separated using a centrifuge, washed with water, and slurried in 550 g of water. This slurry has 1 stipulation.
HNO ₃ was added and the temperature was raised to 80°C while stirring.
While stirring, 80 g of 31% H ₂ O ₂ water was gradually added, and the mixture was kept at 80° C. for 4 hours. The slurry was separated using a centrifuge and washed with water. The amount of carbon on the catalyst was 0.02% by weight, and the amount of nitrogen was 0.05% by weight. Hydration reaction The catalyst obtained above in a hydrated state is 50 g on a dry weight basis, 135 g of water, and 30 g of cyclohexene.
were charged into an autoclave with an internal volume of 300 ml, and after replacing the air in the system with nitrogen, the reaction was carried out at 120°C for 10 minutes with stirring. After the reaction, the product was analyzed by gas chromatography. The concentration of cyclohexanol in the oil phase after reaction is 14.3% by weight
It was hot. Comparative Example 1 Catalyst Preparation Zeolite was synthesized under the same conditions as in Example 1 except as described below. The produced zeolite was separated using a centrifuge, washed with water, and then dried at 120°C for 4 hours.
Then, it was fired at 550° C. for 5 hours under a stream of air.
Furthermore, cation exchange was repeated three times with an aqueous solution of ammonium chloride at a 2 molar concentration. After washing with water, filtering, and drying, it was baked at 400°C for 2 hours. Hydration reaction The reaction was carried out under exactly the same conditions as in Example 1, except that the catalyst prepared above was used. The concentration of cyclohexanol was 8.4% by weight. Example 2 Hydration was carried out in the same manner as in Example 1, except that 50 g of isobutene was used as the olefin, 50 g of the catalyst prepared in Example 1 was used on a dry weight basis, the reaction temperature was 60°C, and the reaction time was 20 minutes. The reaction was carried out. As a result, 26.3% by weight of 2-methyl-2-propanol was present in the aqueous phase. Comparative Example 2 The reaction was carried out under the same conditions as in Example 2, except that the catalyst used in Comparative Example 1 was used. As a result, 20.5% by weight of 2-methyl-2-propanol was present in the aqueous phase. Example 3 Catalyst Preparation 40g of dimethylthiourea instead of 34g of dimethylurea
It was prepared under the same conditions as in Example 1 except that g was used. Hydration Reaction The reaction was carried out under the same conditions as in Example 1, except that the catalyst prepared above was used. As a result, the concentration of cyclohexanol was 14.0% by weight. Comparative example 3 Catalyst preparation 40 g of dimethyl urea instead of 34 g of dimethyl urea
It was prepared under the same conditions as Comparative Example 1 except that . Hydration Reaction The reaction was carried out under the same conditions as in Example 1, except that the catalyst prepared above was used. As a result, the concentration of cyclohexanol was 8.1% by weight. Comparative Example 4 Catalyst Preparation Q: To a mixture of 110 g of blunt sodium silicate and 138 g of water, 3.2 g of aluminum sulfate and 32 g of sodium chloride
g, 9.1 g of concentrated sulfuric acid, 13.7 g of tetrapropylammonium bromide and 190 g of water,
Mixed. The resulting gel-like aqueous mixture was charged into an autoclave and heated to 160° C. for 70 hours while stirring at a circumferential stirring speed of 1.4 m/sec. The produced zeolite was post-treated under the same conditions as in Example 1. Hydration Reaction The reaction was carried out under the same conditions as in Example 1, except that the catalyst prepared above was used. As a result, the concentration of cyclohexanol was 3.1% by weight. Comparative Example 5 Catalyst Preparation Zeolite obtained by hydrothermal synthesis under the same conditions as Comparative Example 4 was post-treated under the same conditions as Comparative Example 1. Hydration Reaction The reaction was carried out under the same conditions as in Example 1, except that the catalyst prepared above was used. As a result, the concentration of cyclohexanol was 5.0% by weight.

Claims (1)

[Claims] 1. When producing alcohol by the hydration reaction of olefin, hydrothermal synthesis is performed in the coexistence of at least one organic compound selected from lower alkyl ureas and lower alkyl thioureas, and the organic compound is further synthesized in the liquid phase with an oxidizing agent. A method for producing alcohol by a hydration reaction of olefin, characterized in that the removed zeolite is used as a catalyst.