JP4129830B2 - Method for producing cyclic saturated alcohols - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing cyclic saturated alcohols. More specifically, the present invention relates to a method for producing a cyclic saturated alcohol by simultaneously hydrogenating and oxidizing an aromatic compound or a cyclic unsaturated hydrocarbon.
[0002]
[Prior art]
Cyclic saturated alcohols and ketones are important as basic chemicals in the organic chemical industry, and their main use is the main raw material for the production of ε-caprolactam. Ε-caprolactam is used for fibers, paints, lacquers, It is important as a raw material for polyamide resins used as compression molding materials and foamed resin materials.
[0003]
Regarding conventional methods for producing cyclic saturated alcohols and ketones, cyclohexanone, which is a highly demanded polyamide resin raw material, will be described. The technology for converting cyclohexanol to cyclohexanone reacts almost quantitatively when a zinc-based catalyst is used. Is known to progress.
[0004]
Also, in the method of hydrogenating benzene to cyclohexane and auto-oxidizing it with air to convert it to a mixture of cyclohexanone and cyclohexanol, using a cobalt catalyst, the reaction is carried out under the conditions of a reaction temperature of 160 ° C and an air pressure of 0.98 MPa. The selectivity with cyclohexane conversion of 6% and cyclohexanone and cyclohexanol is about 77%. When metaboric acid is used as a catalyst under the above reaction conditions, the conversion rate is 5% and the selectivity is improved to 87%.
[0005]
However, in these methods, the reaction products cyclohexanone and cyclohexanol are more reactive than cyclohexane, which is the reaction raw material, and therefore, in order to prevent sequential oxidation and maintain good selectivity, the conversion rate is 6%. It is difficult to raise it above. Therefore, the current cyclohexanone production process is forced to operate at a very low efficiency with a single flow yield of 5% or less. Furthermore, this process requires recovery and purification of unreacted cyclohexane, which is problematic in terms of energy efficiency.
[0006]
In addition, a method of directly synthesizing the polyamide intermediate cyclohexanone oxime by reacting cyclohexane and nitrosyl chloride using light energy was proposed and temporarily operated. Its production has been discontinued.
[0007]
Furthermore, a method for producing cyclohexanone using toluene as a starting material via cyclohexylcarboxylic acid has also been proposed, but this method has a high production price due to the complicated production process, and has not been replaced by the current method. .
[0008]
A method of producing cyclohexanone in a single stage while avoiding complicated reaction systems such as these methods has also been proposed. A method of producing cyclohexanone by directly oxidizing cyclohexane using an electrolyte membrane (Nature Vol. 21, June 1990), a method of directly oxidizing hydrocarbons by biological means using a metal complex catalyst (J. Am. Chem. Soc. 114, 7913-4, 1992) However, each method uses a large amount of expensive additives, and the production amount of the target cyclohexanone is very small.
[0009]
Also, a method for producing cyclohexanol via phenol obtained from benzene has been studied. A common method for producing phenol is the cumene method, which is used by over 90% in Europe and the United States. In this method, benzene and propylene are reacted to form cumene, and then oxidized with air using a cobalt salt catalyst to form cumene hand peroxide, and then decomposed into phenol and acetone using an acid catalyst. This method has a high selectivity and is a very good method, but since phenol and acetone are co-produced at a ratio of 1: 1, the price of phenol depends on the demand for acetone. Currently, acetone is in excess of demand, which has forced production to shrink.
[0010]
Recently, an attempt to produce only phenol directly from benzene has been proposed. A method using nitrous oxide as an oxidizing agent (Appl. Catal. A. Vol. 98, p. 33, 1993) ), Methods using hydrogen peroxide as an oxygen source (JP-A-6-1738, JP-A-7-69950), methods using supported iron catalysts, noble metal catalysts, zeolite catalysts, heteropolyacid catalysts, etc. are actually proposed. Has been. Among these methods, synthesis of nitrous oxide is not easy, and the use of heteropolyacid has the advantage that 30 %% of phenol is produced per hydrogen peroxide and the only by-product is water, but it is peroxidation. The price of hydrogen is a bottleneck.
[0011]
The above-described method for producing cyclohexanol via phenol requires further hydrogenation after phenol production, and there are many unnecessary co-products, so it lacks practicality, not only from an economic standpoint, but also from an environmental standpoint. Also have many problems.
[0012]
Furthermore, a method of partially hydrogenating benzene to produce cyclohexene and hydrating it to produce cyclohexanol has also been studied, but in the first step of this method, benzene is partially hydrogenated to obtain cyclohexene. In the second step, ZSM-5, which is a fixed acid hydration catalyst, is expensive. In addition, there are problems in the life, recovery, regeneration, etc., which are not only factors that increase the product price, but also the problem that the hydration reaction rate does not exceed 10% or more. Therefore, there is a disadvantage that a lot of energy is used for recovery of cyclohexene.
[0013]
For this reason, the current situation is that the advent of a cyclohexanol synthesis method in a simpler process is expected.
[0014]
[Problems to be solved by the invention]
An object of the present invention is to provide a method for producing a cyclic saturated alcohol in a simple process with a high yield by simultaneously hydrogenating and oxidizing an aromatic compound or a cyclic unsaturated hydrocarbon.
[0015]
[Means for Solving the Problems]
The object of the present invention is to coat the surface of a hydrogen selective permeable metal membrane formed on a porous membrane support with a hydrogen selective permeable polymer material, and to treat the surface coated with the polymer material as a hydrogen permeable upstream side. The reaction vessel is divided into a plurality of parts by the diaphragm , and hydrogen permeated through the diaphragm from one section and oxygen in the other section adjacent thereto are brought into contact with the aromatic compound or the cyclic unsaturated hydrocarbon, This is achieved by a method of producing a cyclic saturated alcohol by simultaneously performing a hydrogenation reaction and an oxidation reaction. By adjusting the reaction conditions of this hydrogenation reaction and oxidation reaction, cyclic saturated ketones can be produced together with cyclic saturated alcohols.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
A diaphragm in which a hydrogen selective permeable metal membrane is formed on a porous membrane support is installed at a position where the reaction vessel is divided into a plurality of parts, and has an action of activating hydrogen that permeates the membrane. .
[0017]
Here, as the porous membrane support, a porous hollow fiber membrane made of at least one of alumina, silica, zirconia and the like is generally used. A hydrogen selective permeable metal membrane is formed on these porous hollow fiber membranes. As the metal film, a metal film of palladium, niobium, tantalum, vanadium or the like, or a metal film coated with palladium on the film surface of niobium, tantalum, vanadium or the like, and further, a first transition metal, a second transition metal, or a third transition metal Examples thereof include alloy films of lanthanide elements, actinide elements or elements such as yttrium, cerium, silver, nickel and titanium and palladium, niobium, tantalum and palladium.
[0018]
For example, in the case of a Pd alloy film, the alloy film is formed by repeating each supporting step of Pd and a metal that can be alloyed therewith in an arbitrary order as needed several times, and then at about 600 to 900 ° C. for about 1 It is performed by heat-treating for ~ 12 hours and alloying. At this time, the metal is supported by attaching a metal salt solution by an impregnation method, a dip coating method, or the like, and then performing a heat treatment at a temperature corresponding to the type of the metal salt.
[0019]
Formation of these metal films on the film support is performed using a low temperature metal organic chemical vapor deposition method according to a conventional method. The method shown in FIG. 2 is a method described in Japanese Patent Application Laid-Open No. 11-300182, which is suitable for forming a porous ceramic hollow fiber (membrane support) from the Pd source material installed inside the reaction tube. By supplying the sublimated Pd source material to the film forming range by the flowing carrier gas, a Pd film is formed in a certain film forming range of the porous ceramic hollow fiber.
[0020]
Inside the reaction tube 11 as a reactor, a porous ceramic hollow fiber 12 is hermetically fixed by an O-ring or the like, and the inside of the hollow fiber 12 is continuously exhausted by a vacuum pump 13. Here, the part other than the film forming range 14 of the porous ceramic hollow fiber 12 is hermetically sealed with glass such as Na ₂ OB ₂ O ₃ —SiO ₂ glass. The inside of the reaction tube 11 is also evacuated by a vacuum pump 13 ', the internal pressure of the hollow fiber 12 is measured by a vacuum gauge 15, and the internal pressure of the reactor 11 is measured by a vacuum gauge 15'. Controlled by pressure regulating valves 16, 16 '.
[0021]
The carrier gas from the gas supply unit 17 is supplied into the reactor 11 through the flow rate controller 18. The internal pressures of the reactor 11 and the porous ceramic hollow fiber 12 vary depending on the carrier gas flow rate and the displacement of the vacuum pumps 13 and 13 ', and therefore cannot be specified. The internal pressure of the tube 11 is maintained at about 20 to 2000 Pa, and the internal pressure of the porous ceramic hollow fiber 12 is maintained at about 1 to 500 Pa. In FIG. 2, the carrier gas forms a flow from the Pd source material 19 toward the film forming region 14 of the porous ceramic hollow fiber 12.
[0022]
The reaction tube 11 is heated by a heater divided into at least two parts consisting of a heater 20 in the Pd source material installation part and a heater 21 in the support film forming part, and the temperature is controlled by temperature controllers 22 and 22 '. Be controlled.
[0023]
The film formation range 14 of the porous ceramic hollow fiber 12 is arranged in the support film-forming part 21 of the heater, and the Pd source material placed in the reaction tube 11 kept below the thermal decomposition temperature of the Pd source material 19 19 is heated to the sublimation temperature by the Pd source material installation unit 20 of the heater. When the pressure in the reaction tube 11 increases with the sublimation of the Pd source material 19, the temperature of the support film forming portion 21 of the heater is rapidly raised to a film forming temperature of about 200 to 500 ° C. The inside of 11 is defined as the film forming temperature.
[0024]
The sublimated Pd source material 19 is forcibly supplied to the film forming range 14 by the flow of the carrier gas, and if this film forming temperature is maintained for about 1 to 3 hours, the Pd produced by the thermal decomposition is hollowed out from the porous ceramics. The Pd thin film is formed on the outer surface of the yarn 12 and in the pores in the vicinity thereof. Here, palladium acetate, palladium acetylacetonate, or the like is used as the Pd source material.
[0025]
As a method for forming a metal film, in addition to such a vapor deposition method, a metal plating method such as a conventional metal thin film formation method or an electroless plating method as described above can be used, and a metal plating method is used. In this case, it is preferable that the surface of the membrane support on which the metal film is formed is activated in advance.
[0026]
Using a membrane with the hydrogen-permeable polymer material coated on the surface of these hydrogen-permeable metal membranes and the surface coated with the polymer material on the upstream side of hydrogen permeation reduces the effects of hydrogen embrittlement and coexisting gases. In addition, the surface of the metal film is coated with a polymer material, particularly an elastic rubber-like polymer material having a glass transition temperature of room temperature or lower, so that the metal thin film can be protected against contact and sliding with other members. And effectively preventing defects in the metal thin film.
[0027]
When polysulfone, polyimide, polyamide, polycarbonate, cellulose acetate or the like is used as the hydrogen selective permeable polymer material, these are all glassy polymers having a high glass transition temperature, and these are represented by Pd-based materials. When used for coating a metal film, there is a concern about peeling due to the difference in the coefficient of thermal expansion between the two during heating and cooling. Therefore, for this type of application, a hydrogen selective permeable polymer material having a glass transition temperature lower than room temperature and having elasticity at room temperature or higher is preferable, and the heat resistance of the polymer material is a hydrogenation reaction and an oxidation reaction. It is selected according to the reaction temperature.
[0028]
From this point of view, polymer materials such as polysiloxane, polybutadiene, butyl rubber, polychloroprene, polyvinylidene fluoride, polyamide, polyester, polyethylene, and polypropylene can be used for coating the metal film. From the viewpoint of properties, polysiloxane polymers are preferred. There are no particular limitations on the method for coating the metal film with these polymer substances as long as the metal film can be coated with an arbitrary film thickness, such as dip coating, spray coating, and spin coating. In general, in order to control the film thickness set to about 1 to 50 μm, a method of diluting with a solvent and using it as a solution is preferable.
[0029]
An embodiment of a reaction vessel divided into a plurality of parts by a diaphragm using such a porous ceramic hollow fiber membrane support is shown in FIG. The reaction vessel 31 is a double tube reactor comprising an inner tube (inner vent tube) 32 and an outer tube (outer vent tube) 33. As the inner pipe 32, a porous ceramic hollow fiber membrane 12 in which a hydrogen selective permeable polymer material-covered hydrogen selective permeable metal membrane is formed on a surface thereof is hermetically connected via a connector 34. Is used. Further, as the porous ceramic hollow fiber membrane 12, a portion of the hydrogen selective permeable metal membrane other than the film production range 14 is hermetically sealed with glass or the like. The inner pipe 32 is coaxially supported by an outer pipe 33 made of SUS, etc., and the film forming range 14 of the inner pipe is used as a diaphragm, and a double pipe reactor is connected to the inner pipe portion 32 and the outer pipe portion 33. It is divided into two parts . The inner pipe 32 is provided with a reactant inlet 35 and a reaction product outlet 36, while the outer pipe 33 is provided with a hydrogen inlet 37 and a outlet 38, and a metal film forming portion of the inner pipe 32. A heater 39 that sufficiently covers 14 is provided on the outer peripheral surface of the outer tube, and the temperature is controlled by a temperature controller (not shown) to which the thermocouple 40 and the heater 39 are connected. Oxygen is introduced into the inner tube along with the reactants.
[0030]
The hydrogenation reaction and the oxidation reaction using such a reaction vessel are performed as a simultaneous reaction by activating oxygen by contacting hydrogen activated through the partition wall 14. The reaction temperature at that time is about −200 to 900 ° C., preferably about −10 to 600 ° C., and the reaction pressure is 0.098 to 147 MPa, preferably 0.49 to 49 MPa.
[0031]
Examples of aromatic compounds or cyclic unsaturated hydrocarbons that are reactants that undergo hydrogenation and oxidation reactions include benzene, toluene, xylene, naphthalene, tetralin, biphenyl, cyclohexylbenzene, cyclooctadiene, cyclooctatriene, cyclododecatriene And cyclododecatetraene. These hydrocarbons may have a substituent such as an amino group, a hydroxyl group, a carboxyl group, an ester group, a cyano group, a nitro group, a hageron, and oxygen. Aromatic heterocyclic compounds containing oxygen, nitrogen and sulfur atoms such as pyridine, furan, pyrrole and thiophene are also used.
[0032]
Pure hydrogen or a gas or solution containing hydrogen can be used as hydrogen, and pure oxygen, ozone, or a gas or solution containing these can be used as oxygen. The use ratio of hydrogen and oxygen to the aromatic compound or cyclic unsaturated hydrocarbon can be controlled by adjusting the feed flow rate, respectively.
[0033]
In general, the conversion of aromatics or cyclic unsaturated hydrocarbons is limited to about 0.01 to 50%, preferably about 1 to 25%. When the conversion rate is higher than this, the selectivity of the product is lowered. The ratio of hydrogen and oxygen to be used with respect to the hydrocarbon is used at such a ratio as to achieve the above conversion rate.
[0034]
The hydrogen used for the hydrogenation reaction and the oxygen used for the oxidation reaction are, for example , benzene as an aromatic compound and the supply flow rate is 0.14 ml / min as shown in the respective reference examples described later. When the oxygen gas flow rate is increased to 11.4 ml / min, 15.2 ml / min, 19.0 ml / min, and 25.5 ml / min at a gas flow rate of 3 ml / min, the reaction product is converted from cyclohexanol alone to phenol and further cyclohexanone. It will come together. On the contrary, when the hydrogen gas flow rate is increased from 3 ml / min to 10.0 ml / min at an oxygen gas flow rate of 2.2 ml / min, cyclohexanone and phenol are co-produced from cyclohexanol alone. Therefore, the relative supply amount of hydrogen and oxygen is adjusted in accordance with the case where cyclohexanol alone is required as a reaction product or when cyclohexanone is produced together with the reaction product.
[0035]
【The invention's effect】
In the method of the present invention, the surface of the hydrogen selective permeable metal membrane formed on the porous membrane support is coated with a hydrogen selective permeable polymer material, and the surface coated with the polymer material is the upstream side of hydrogen permeation. Using a diaphragm catalyst, hydrogenation and oxidation of aromatic compounds or cyclic unsaturated hydrocarbons with activated hydrogen and oxygen can be carried out simultaneously, and cyclic saturated alcohols are produced in a simple process and with good yield. By selecting reaction conditions, cyclic saturated ketones can be produced together. When a hydrogen selective permeable metal membrane is coated with a hydrogen selective permeable polymer material, particularly an elastic rubbery polymer material having a glass transition temperature of room temperature or lower, preferably a polysiloxane polymer, hydrogen embrittlement or The influence of the coexisting gas is reduced , the metal thin film is protected against contact and sliding with other members, and defects in the metal thin film are effectively prevented.
[0036]
【Example】
Next, the main part of the present invention will be described for a reference example .
[0037]
Reference example 1
According to the method described in JP-A-11-300182, a hydrogen selective permeable membrane made of Pd membrane-forming porous ceramic hollow fibers was produced using the apparatus shown in FIG.
[0038]
As the membrane support, a porous alumina hollow fiber having an outer diameter of 2.0 mm, an inner diameter of 1.7 mm, a length of 350 mm, an average pore diameter of 150 nm, a specific surface area of 6 m ² / g, and a porosity of 43% by volume is used. The center part was 100 mm, and the other part was hermetically sealed with glass (Na ₂ OB ₂ O ₃ —SiO ₂ glass), and one was installed in the center of the reactor. Further, about 0.75 g of palladium acetate was used as the Pd source material. The reactor uses a SUS pipe with an inner diameter of 85 mm and a length of 400 mm, and the heater uses a resistance heating electric furnace with a length of 350 mm, and is divided into two parts: a Pd source material installation part and a support film-forming part. The temperature was controlled independently.
[0039]
When forming a film, first, argon gas as a carrier gas is flowed at a flow rate of 100 cm ³ / min while exhausting the reactor, and the support body is also exhausted at the same time, so that the pressure in the reactor is about 300 to 500 Pa. The pressure in the support was controlled to about 10 to 200 Pa, respectively. Slowly raise the temperature of the Pd source material installation part to 200 ° C. and the temperature of the support film forming part to 205 ° C. and keep it at that temperature, and when an increase in pressure in the reactor begins to be observed, The film forming temperature of the support film forming part was rapidly raised to 300 ° C. at a rate of temperature increase of 10 ° C./min or more and held at that temperature for 2 hours. The Pd-supported porous alumina hollow fiber thus obtained had a Pd-supported film thickness of 1 μm on the support porous portion, and the supported amount was about 8.0 mg.
[0040]
The Pd membrane-supported α-alumina porous hollow fiber also used as the inner vent pipe, thus prepared, was used as a diaphragm-type catalyst and was attached to the reactor shown in FIG. It was. That is, hydrogen gas permeates from the outer vent pipe of this flow type reactor into the inner vent pipe at a flow rate of 3 ml / min, and the inner vent pipe has oxygen gas flow rate of 2.2 ml / min and flow rate of 0.2 ml / min. When gaseous benzene was introduced and reacted at a reaction temperature of 200 ° C., a reaction product having a benzene conversion of 5.8% and a cyclohexanol concentration of 91% in the product was obtained.
[0041]
Reference example 2
In the reaction of Reference Example 1 , when the flow rate of gaseous benzene was changed to 0.3 ml / min, a reaction product having a benzene conversion of 3.3% and a cyclohexanol concentration of 88% in the product was obtained.
[0042]
Reference example 3
In the reaction of Reference Example 1 , when the flow rate of gaseous benzene was changed to 0.55 ml / min, a reaction product having a benzene conversion of 1.2% and a cyclohexanol concentration of 80% in the product was obtained.
[0043]
Reference example 4
In the reaction of Reference Example 1 , when the flow rate of the supplied hydrogen gas is changed to 10.0 ml / min, a reaction product with a benzene conversion of 1.5%, a cyclohexanol concentration of 18%, a cyclohexanone concentration of 11%, and a phenol concentration of 63% Things were obtained.
[0044]
Reference Example 5
In the reaction of Reference Example 1 , when the supply oxygen gas flow rate is changed to 11.4 ml / min and the gaseous benzene flow rate is changed to 0.14 ml / min, a reaction product with a benzene conversion of 1.2% and a cyclohexanol concentration of 72% in the product is produced. Things were obtained.
[0045]
Reference Example 6
In the reaction of Reference Example 1 , when the supplied oxygen gas flow rate was changed to 15.2 ml / min and the gaseous benzene flow rate was changed to 0.14 ml / min, the benzene conversion was 2.8%, the cyclohexanol concentration in the product was 43%, and the phenol concentration. 48% of the reaction product was obtained.
[0046]
Reference Example 7
In the reaction of Reference Example 1 , when the supplied oxygen gas flow rate was changed to 19.0 ml / min and the gaseous benzene flow rate was changed to 0.14 ml / min, the benzene conversion was 2.8%, the cyclohexanol concentration in the product was 28%, and the phenol concentration 62% of the reaction product was obtained.
[0047]
Reference Example 8
In the reaction of Reference Example 1 , when the supply oxygen gas flow rate was changed to 25.2 ml / min and the gaseous benzene flow rate was changed to 0.14 ml / min, the benzene conversion rate was 1.3%, the cyclohexanol concentration in the product was 13%, and cyclohexanone 10 %, Phenol 68% reaction product was obtained.
[0048]
Reference Example 9
In the reaction of Reference Example 1 , when cyclooctadiene was used instead of gaseous benzene, the flow rate of 0.3 ml / min was changed to 15.2 ml / min, and the reaction temperature was changed to 250 ° C. A reaction product having a cyclooctanol concentration of 95% in the product at a rate of 6.8% was obtained.
[0049]
Reference Example 10
In the reaction of Reference Example 1 , using cyclooctatriene at a flow rate of 0.3 ml / min instead of gaseous benzene, changing the supply oxygen gas flow rate to 15.2 ml / min and the reaction temperature to 250 ° C., cyclooctatriene conversion A reaction product having a cyclooctanol concentration of 96% in the product at a rate of 8.3% was obtained.
[0050]
Reference Example 11
In the reaction of Reference Example 1 , if cyclododecatriene was used instead of gaseous benzene, the flow rate of 0.3 ml / min was changed to 15.2 ml / min, and the reaction temperature was changed to 250 ° C., cyclododecatriene conversion. A reaction product having a cyclododecanol concentration of 97% in the product at a rate of 9.6% was obtained.
[0051]
Reference Example 12
In the reaction of Reference Example 1 , when cyclododecatetraene was used instead of gaseous benzene, the flow rate of 0.3 ml / min was changed to 15.2 ml / min, and the reaction temperature was changed to 250 ° C., cyclododecatetra. A reaction product having an ene conversion of 11.2% and a cyclododecanol concentration of 98% in the product was obtained.
[Brief description of the drawings]
FIG. 1 is a schematic view of a reaction apparatus used in the method of the present invention.
FIG. 2 is a schematic view of a Pd supporting method by a low temperature metal organic chemical vapor deposition method for producing a Pd supported ceramic hollow fiber used in the reactor.
[Explanation of symbols]
11 reaction tubes
12 Porous ceramic hollow fiber
14 Film formation range
17 Carrier gas supply
19 Pd source material
20 Pd source material installation part of the heater
21 Heater support film forming section
31 reaction vessel
32 Inner pipe (inner vent pipe)
33 Outer pipe (outer vent pipe)
35 Reactant inlet
36 outlet
37 Hydrogen inlet
38 outlet
39 Heater
40 Thermocouple

Claims (5)

A plurality of reaction vessels are formed by a membrane in which the surface of the hydrogen selective permeable metal membrane formed on the porous membrane support is coated with a hydrogen selective permeable polymer material, and the surface coated with the polymer material is on the hydrogen permeable upstream side. The hydrogen permeated through the diaphragm from one section and the oxygen in the other section adjacent thereto are brought into contact with an aromatic compound or a cyclic unsaturated hydrocarbon, and a hydrogenation reaction and an oxidation reaction are performed. A process for producing cyclic saturated alcohols, characterized in that   The method for producing a cyclic saturated alcohol according to claim 1, wherein the cyclic saturated alcohol is produced together with the cyclic saturated alcohol. The method for producing cyclic saturated alcohols according to claim 1 or 2, wherein the diaphragm comprises a porous ceramic hollow fiber membrane as a support and a hydrogen-permeable metal material-coated hydrogen-permeable metal membrane formed on the support. . The method for producing a cyclic saturated alcohol according to claim 1, 2 or 3, wherein the hydrogen selective permeable high molecular weight material covering the surface of the hydrogen selective permeable metal membrane is an elastic rubbery high molecular weight material .   The process for producing cyclic saturated alcohols according to claim 1, 2, 3 or 4, wherein a double-pipe reactor having a porous ceramic hollow fiber membrane as an inner tube is used as a reaction vessel divided into a plurality of parts by a diaphragm. .

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