JPWO2007058251A1 - Method for producing cycloalkyl alkyl ether - Google Patents

Abstract

The present invention relates to a cycloalkyl alkyl ether having a step of reacting a raw material alicyclic olefin having a chain conjugated diene compound content and a cyclic conjugated diene compound content of 10 ppm or less with an alcohol in the presence of a solid acid catalyst. It is a manufacturing method. According to the present invention, there is provided a method for producing a cycloalkyl alkyl ether capable of producing a cycloalkyl alkyl ether in a high yield by sufficiently suppressing a decrease in catalytic activity even after continuous operation for a long time. The

Description

  The present invention relates to a cycloalkylalkyl useful as a cleaning solvent for electronic parts and precision machine parts, a solvent for chemical reaction, a solvent for extraction, a solvent for crystallization, a chromatographic eluent, a solvent for electronic and electrical materials, and a release agent. The present invention relates to a method for producing ether.

  Conventionally, a method for producing ethers by addition reaction of an olefin and an alcohol in the presence of a solid acid catalyst is known. For example, (a) a method using a crystalline aluminosilicate as a catalyst (Patent Document 1), (b) a method using a special aluminosilicate having many external surface acid sites as a catalyst (Patent Document 2), and (c) a heteropolysiloxane as a catalyst. A method of using an oxide of tungsten in which crystal water having an acid is adjusted to an average of 3.0 molecules or less per molecule of the heteropolyacid (Patent Document 3), and (d) a water content of 5% by weight or less as a catalyst A method using an acidic ion exchange resin (Patent Document 4) is known.

  However, when these solid acid catalysts are used and cycloalkyl alkyl ethers are produced on an industrial scale using alicyclic olefins as starting materials, the catalyst activity decreases with time during long-term continuous operation. For this reason, there has been a problem that it is necessary to regenerate, replenish, or replace a catalyst whose activity has frequently decreased.

As a method for solving this problem, Patent Document 5 discloses a method for producing a cycloalkyl alkyl ether by reacting an alicyclic olefin and an alcohol in the presence of a solid acid catalyst, wherein the content of the chain conjugated diene compound is as follows. It has been proposed to suppress a decrease in catalyst activity over time by using an alicyclic olefin of 10 ppm or less. In the examples of this document, it is described that the catalytic activity was not substantially reduced in continuous operation up to 150 hours.
JP 59-25345 A Japanese Patent Laid-Open No. 61-249945 JP-A-5-163188 US2005065060 JP 2004-292358 A

In the production of cycloalkyl alkyl ethers on an industrial scale using alicyclic olefins as starting materials using a solid acid catalyst, 200 hours (about 8 days) or more are continuously produced from the viewpoint of achieving sufficient cost reduction. It is desirable to operate.
However, even the method described in Patent Document 5 cannot sufficiently suppress the decrease in catalyst activity, and it has been difficult to perform continuous operation for 200 hours (about 8 days) or longer.

  The present invention has been made in view of such a state of the art, and even when continuous operation for 200 hours (about 8 days) or more is carried out, the decrease in the catalytic activity is sufficiently suppressed. It is an object of the present invention to provide a method for producing a cycloalkyl alkyl ether that can be continuously produced with high yield.

Commercially available alicyclic olefins usually contain about 3000 ppm and about 300 ppm of a chain conjugated diene compound and a cyclic conjugated diene compound derived from the raw material of the olefin, respectively.
As a result of intensive studies to achieve the above object, the present inventors have identified not only the content of the chain conjugated diene compound but also the content of the cyclic conjugated diene compound in the alicyclic olefin used as a raw material. Surprisingly, when the cycloalkyl alkyl ether was produced by continuous operation for 200 hours or more, it was found that the catalytic activity was not substantially lowered and the present invention was completed. It was.

Thus, according to the present invention, the following methods for producing cycloalkyl alkyl ethers (1) to (4) are provided.
(1) A cycloalkyl alkyl ether having a step of reacting a raw material alicyclic olefin having a chain conjugated diene compound content and a cyclic conjugated diene compound content of 10 ppm or less with an alcohol in the presence of a solid acid catalyst. Production method.
(2) The production method according to (1), wherein the solid acid catalyst is an acidic ion exchange resin.
(3) The production method according to (1) or (2), wherein the chain conjugated diene compound is 1,3-pentadiene and the cyclic conjugated diene compound is cyclopentadiene.
(4) The production method according to any one of (1) to (3), wherein cyclopentylmethyl ether is produced.

  According to the production method of the present invention, even if continuous operation is performed for 200 hours (about 8 days) or more, the decrease in the catalyst activity is sufficiently suppressed, and the cycloalkyl alkyl ether can be produced continuously in a high yield. .

It is a schematic diagram which shows an example of the reaction apparatus for enforcing the manufacturing method of this invention. It is a schematic diagram which shows an example of the reaction apparatus for enforcing the manufacturing method of this invention. It is a schematic diagram which shows an example of the apparatus which combined the reaction apparatus and the distillation apparatus for implementing the manufacturing method of this invention.

Explanation of symbols

1a, 1b, 1c, 1d ... storage tanks 2a, 2b, 2c, 2d ... heating / vaporizers 3a, 3b, 3c, 3d, 3e, 3f, 3h, 3h ... reaction column 4 ... distillation apparatus 5 ... piping

  The process for producing a cycloalkyl alkyl ether according to the present invention comprises reacting a raw material alicyclic olefin having a chain conjugated diene compound content and a cyclic conjugated diene compound content of 10 ppm or less with an alcohol in the presence of a solid acid catalyst. It has the process to make it feature.

  In the present specification, the “raw alicyclic olefin” refers to a crude alicyclic olefin containing impurities such as a chain conjugated diene compound and a cyclic conjugated diene compound as a raw material. The “alicyclic olefin” refers to the alicyclic olefin itself as a compound.

  The alicyclic olefin used in the present invention has an aliphatic monocyclic or polycyclic skeleton (hereinafter, these skeletons may be collectively referred to as “ring skeleton”), and these rings. A compound having at least one carbon-carbon double bond in the skeleton.

The number of carbon atoms constituting the ring skeleton of the alicyclic olefin to be used is not particularly limited, but is preferably 3 to 20.
Moreover, the alicyclic olefin used is a carbon such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and an isobutyl group in the ring skeleton within a range that does not inhibit the expression of the effect of the present invention An alkyl group having 1 to 4 carbon atoms; an aryl group having 6 to 12 carbon atoms such as a phenyl group, a xylyl group, a tolyl group and a naphthyl group; a halogen atom such as a fluorine atom and a chlorine atom; a nitro group; an amino group; a methoxy group and an ethoxy group An alkoxy group having 1 to 4 carbon atoms such as a group, n-propoxy group, isopropoxy group, n-butoxy group and isobutoxy group; a sulfonic acid group (—SO ₃ H); and a substituent such as a cyano group Also good. The aryl group includes a heteroaromatic hydrocarbon group containing an atom other than a carbon atom such as an oxygen atom or a nitrogen atom. The number and position of substituents in the alicyclic olefin are not particularly limited.

  In the present invention, it is preferable to use an alicyclic olefin having a monocyclic ring having 5 to 8 ring carbon atoms from the viewpoint of availability and the ability to obtain the target product more efficiently, and it has a substituent. Cyclopentene which may be substituted or cyclohexene which may have a substituent is more preferable.

  Specific examples of the cyclopentene which may have a substituent include cyclopentene, 1-methylcyclopentene, 3-methylcyclopentene, 1,3-dimethylcyclopentene, 1-fluorocyclopentene, 1-phenylcyclopentene and the like.

Specific examples of cyclohexene which may have a substituent include cyclohexene, 1-methylcyclohexene, 4-methylcyclohexene, 1,3-dimethylcyclohexene, 1-fluorocyclohexene, 4-chlorocyclohexene and 1-phenyl. Examples include cyclohexene and 4-phenylcyclohexene.
Among these, cyclopentene or cyclohexene is preferable, and cyclopentene is particularly preferable.

  In the raw material alicyclic olefin used in the present invention, it is essential that both the content of the chain conjugated diene compound and the cyclic conjugated diene compound contained therein are 10 ppm or less. The content of the chain conjugated diene compound and the cyclic conjugated diene compound is preferably 5 ppm or less, respectively.

  By using a raw material alicyclic olefin having a chain conjugated diene compound and a cyclic conjugated diene compound contained as impurities of 10 ppm or less, continuous operation for 200 hours (about 8 days) or more is performed. However, the decrease in the catalytic activity is sufficiently suppressed, and the cycloalkyl alkyl ether can be continuously produced with good yield.

  The chain conjugated diene compound is usually a compound having 4 to 10 carbon atoms, and examples thereof include butadiene, 2-methylbutadiene, 1,3-pentadiene, 1,3-hexadiene, 2,4-hexadiene, All of the isomers are also included. When cyclopentene is used as the starting alicyclic olefin, the chain conjugated diene compound contained is substantially 1,3-pentadiene, and the content of 1,3-pentadiene is 10 ppm or less, preferably 5 ppm or less. .

  The cyclic conjugated diene compound is usually a compound having 4 to 10 carbon atoms, for example, cyclobutadiene, methylcyclobutadiene, cyclopentadiene, 1-methylcyclopentadiene, 1,3-cyclohexadiene, 1-methyl-1,3. -Cyclohexadiene etc. are mentioned, and those having isomers are all included. When cyclopentene is used as the raw material alicyclic olefin, the cyclic conjugated diene compound contained is substantially cyclopentadiene, and the content of cyclopentadiene is 10 ppm or less, preferably 5 ppm or less.

  As a method for reducing the content of a conjugated diene compound from a raw material alicyclic olefin containing a chain conjugated diene compound and a cyclic conjugated diene compound (hereinafter, collectively referred to as “conjugated diene compound”) as impurities. Includes a method of adsorbing and removing a conjugated diene compound, a method of converting and removing a conjugated diene compound, and a method of separating and removing a conjugated diene compound. Examples of such methods include (1) a method in which a raw material alicyclic olefin containing a conjugated diene compound is contacted with an adsorbent such as activated clay, and (2) a raw material alicyclic olefin containing a conjugated diene compound is hydrogenated. And (3) a method of purifying a raw material alicyclic olefin containing a conjugated diene compound after bringing it into contact with a solid acid catalyst such as an acidic ion exchange resin.

  The method using the adsorbent of (1) has a short life of the adsorbent, and the method of (2) is difficult to selectively reduce the conjugated diene compound. In particular, the content of the cyclic conjugated diene compound is 10 ppm or less. If you try to reduce it, the original alicyclic olefin itself may be reduced to a cyclic alkane, so the content of both the chain conjugated diene compound and the cyclic conjugated diene compound can be easily reduced to 10 ppm or less. The method (3) that can be performed is preferred.

  Examples of the solid acid catalyst used in the method (3) include those similar to the solid acid catalyst used in the method for producing the cycloalkyl alkyl ether of the present invention described later.

When an acidic ion exchange resin is used as a solid acid catalyst for the reduction of the conjugated diene compound, the water content of the resin is not particularly limited.
The contact between the raw material alicyclic olefin and the acidic ion exchange resin may be performed, for example, by circulating the raw material alicyclic olefin in a column that is appropriately heated and packed with the acidic ion exchange resin. The circulation speed is usually ¹ to 10 hr ⁻¹ as the space velocity in the device (column packed with acidic ion exchange resin) in terms of liquid volume. The space velocity has the same meaning as the liquid space velocity described later. The raw material cycloaliphatic olefin coming out of the column is recovered and further subjected to separation and purification by a known method such as distillation.

  The content of the conjugated diene compound contained in the raw material alicyclic olefin can be quantified by gas chromatography according to a known method.

The alcohol used in the present invention is not particularly limited as long as it can undergo an addition reaction with an alicyclic olefin in the presence of a solid acid catalyst. For reasons such as obtaining a cycloalkyl alkyl ether efficiently, a linear or branched saturated alcohol having 1 to 10 carbon atoms or a cycloalkyl alcohol having 3 to 8 carbon atoms is preferable, and a linear chain having 1 to 6 carbon atoms. A branched saturated alcohol is more preferable, and a linear or branched saturated alcohol having 1 to 3 carbon atoms is more preferable.
The purity of the alcohol used in the present invention is not particularly limited as long as both the chain conjugated diene compound and the cyclic conjugated diene compound have a content of 10 ppm or less. As the alcohols, commercially available alcohols may be used as they are.

Examples of the linear or branched saturated alcohol having 1 to 10 carbon atoms include methyl alcohol (carbon number 1), ethyl alcohol (carbon number 2), n-propyl alcohol (carbon number 3), isopropyl alcohol (carbon number 3). N-butyl alcohol (carbon number 4), isobutyl alcohol (carbon number 4), n-pentyl alcohol (carbon number 5), n-hexyl alcohol (carbon number 6), and the like.
Examples of the cycloalkyl alcohol having 3 to 8 carbon atoms include cyclopropyl alcohol (carbon number 3), cyclopentyl alcohol (carbon number 5), cyclohexyl alcohol (carbon number 6), and the like.
Among the above alcohols, methyl alcohol is particularly preferable.

  The solid acid catalyst used in the present invention is a solid acid catalyst at room temperature (20 to 30 ° C.), which is insoluble or hardly soluble in water.

  Examples of the solid acid catalyst to be used include acidic ion exchange resins, metal oxides, zirconium compounds and the like. Among these, acidic ion exchange resins are used from the viewpoint of yield and ease of application to a fixed bed reactor. Is preferred. As the solid acid catalyst, one or more of the same or different catalysts may be used in appropriate combination.

  The acidic ion exchange resin is composed of an insoluble and porous synthetic resin having an acidic ion exchange group on a fine three-dimensional network polymer base, and is generally called a cation exchange resin.

  Acidic ion exchange resins can be broadly classified into gel type and porous type as classified from the geometric structure of acidic ion exchange resin. In the present invention, both gel type resin and porous type resin are used. Can be used. Acid ion exchange resin types include a proton type in which the proton part of the ion exchange group is a proton as it is, and an alkali metal salt type in which the proton of the ion exchange resin is exchanged for an alkali metal ion. Exchange resins are preferred.

  As the proton type acidic ion exchange resin, a commercially available one may be used as it is, or one pretreated with an acid may be used. As an acid treatment method, for example, an acidic ion exchange resin is added to dilute acid such as dilute hydrochloric acid or dilute sulfuric acid, and the mixture is allowed to stand or stir at 20 ° C. to 100 ° C. for several minutes to several tens of hours. A method in which a dilute acid is allowed to flow through the ion exchange resin until the liquid eluted from one side of the column becomes acidic is mentioned. It is preferable to use the pretreated ion exchange resin after thoroughly washing with distilled water or deionized water to remove excess acid. Moreover, acidic ion exchange resin can be repeatedly used by performing normal reproduction | regeneration processing.

  As the acidic ion exchange resin, as a polymer substrate having a sulfonic acid group or a carboxylic acid group as an ion exchange group and bonded with the ion exchange group, a polymer substrate obtained by condensation polymerization of phenol and formaldehyde, styrene or Examples thereof include those having a copolymer substrate of halogenated styrene and divinylbenzene. Examples of the alkali metal include sodium and potassium.

  Among these, from the viewpoint of easy availability and handling, it is preferable to use a sulfonic acid type strongly acidic ion exchange resin having a sulfonic acid group as an ion exchange group, and a copolymer of styrene or halogenated styrene and divinylbenzene. It is more preferable to use a sulfonic acid type styrene strongly acidic ion exchange resin having a polymer substrate and having a sulfonic acid group as an ion exchange group.

  Preferable specific examples of the sulfonic acid type styrenic strongly acidic ion exchange resin include SK1B, PK208, PK216, PK228, HPK25, RCP145, RCP-160M, RCP-160H, RCP-170H manufactured by Mitsubishi Chemical Corporation; K1221, K1431, K1481, K1491, K2431, K2621, K2641; Amberlist 15 and Amberlist CSP-2 manufactured by Rohm and Haas.

  The apparent density (g / LR) of these acidic ion exchange resins is usually 500 to 1000, preferably 600 to 900. The water content before dehydration (including the concept of drying) is usually 30 to 70% by weight. Although the average particle diameter of acidic ion exchange resin is not specifically limited, Usually, 0.02 mm-10 mm, Preferably it is the range of 0.5 mm-2 mm. Here, the apparent density can be obtained by dividing the weight of the acidic ion exchange resin by the apparent volume of the resin measured using a graduated cylinder. The average particle diameter can be measured with a Coulter counter.

  The water content of the acidic ion exchange resin used in the present invention is preferably 5% by weight or less, more preferably 3% by weight or less, and still more preferably 2% by weight or less. When such an acidic ion exchange resin is used, the desired cycloalkyl alkyl ether can be obtained with high selectivity and conversion, which is preferable.

  In order to obtain an acidic ion exchange resin having a water content of 5% by weight or less, it may be dehydrated to remove water before use. The method for dehydrating the acidic ion exchange resin is not particularly limited as long as it is a method that can be dehydrated to obtain an acidic ion exchange resin having a water content of 5% by weight or less.

  As a method for dehydrating the acidic ion exchange resin, for example, (v) the acidic ion exchange resin is accommodated in a normal dryer, and the pressure is 50 to 120 ° C., preferably 80 to 110 ° C. for several minutes under normal pressure or reduced pressure. (W) Acid ion exchange resin is heated and dried at a predetermined temperature (room temperature to about 100 ° C.) for several minutes to several hours under inert gas flow conditions; (x) acidic ions And a method in which a solvent having a low water content (usually 0.1% by weight or less) is passed through the exchange resin for washing; (y) a combination of the above methods (v) to (x); and the like.

Examples of the solvent used in the methods (x) and (y) include methyl alcohol, ethyl alcohol, n-propyl alcohol, and isopropyl alcohol. Moreover, although the distribution | circulation speed | rate of a solvent is not specifically limited, It is 1-10 hr < ^-1 > normally as a space velocity in an apparatus (column filled with acidic ion exchange resin) in conversion of the liquid volume.

  The water content of the acidic ion exchange resin before and after dehydration can be measured by the Karl Fischer coulometric titration method.

  Examples of the metal oxide used as the solid acid catalyst include Ge, Sn, Pb, B, Al, Ga, Zn, Cd, Cu, Fe, Mn, Ni, Cr, Mo, W, Ti, and Zr. One or more of metal oxides selected from the group consisting of Hf, Y, La, Ce, Yb, and Si; mordenite, erionite, ferrierite, zeolite A, zeolite Y, zeolite X, ZSM- Crystalline aluminosilicates such as type 5 zeolite, zeolites such as metalloaluminosilicates and metallosilicate zeolites containing foreign elements such as boron, iron, gallium, titanium, copper and silver; water-insoluble water composed of tungsten compounds and zirconium compounds And double oxides such as binary catalysts.

Examples of the tungsten compound include orthotungstate, paratungstate, and metatungstate represented by M _a WO ₄ (wherein M represents a metal ion or an ammonium ion, and a represents 1 or 2). Etc.
Examples of the zirconium compound include zirconia sulfate, which is a reaction product of zirconium hydroxide and sulfuric acid or a water-soluble sulfate.

  A cycloalkyl alkyl ether is prepared by mixing a raw material alicyclic olefin having a chain conjugated diene compound content and a cyclic conjugated diene compound content of 10 ppm or less and an alcohol, and reacting them in the presence of a solid acid catalyst. Can be obtained.

  The water content of the mixture of the raw material alicyclic olefin and alcohol (hereinafter referred to as the raw material mixture) is not particularly limited, but it is desirable that the water content be smaller in order to obtain the target cycloalkyl alkyl ether more efficiently. Preferably it is 1 weight% or less, More preferably, it is 500 ppm or less. Here, the water content of the raw material mixture can be measured by the Karl Fischer coulometric titration method.

  In the present invention, the reaction between the alicyclic olefin and the alcohol can be carried out in a solvent or diluent that is inert to all of the solid acid catalyst, the alicyclic olefin, and the alcohol.

  The solvent or diluent may be used alone or in the form of a mixture of two or more, or a mixture thereof. However, it is not preferable that a compound that forms a cyclic conjugated diene compound is present during the reaction.

Solvents and diluents used include aliphatic saturated hydrocarbons such as n-butane, n-pentane, n-hexane, n-heptane, n-octane, n-nonane and n-decane; benzene, toluene, ethylbenzene, Aromatic hydrocarbons such as xylene, anisole, cumene, nitrobenzene; cyclopentane, alkyl-substituted cyclopentanes, alkoxy-substituted cyclopentanes, nitro-substituted cyclopentanes, cyclohexane, alkyl-substituted cyclohexanes, alkoxy-substituted cyclohexanes, nitro-substituted Cyclohexanes, cycloheptane, alkyl-substituted cycloheptanes, alkoxy-substituted cycloheptanes, nitro-substituted cycloheptanes, cyclooctane, alkyl-substituted cyclooctanes, alkoxy-substituted cyclooctanes, nitro-substituted cyclo Alicyclic saturated hydrocarbons such as octane compounds; nitrogen, argon, air, such as helium and the like.
The amount of the solvent and diluent used is not particularly limited, and any amount can be selected as long as the reaction is not inhibited.

  Although the reaction temperature of an alicyclic olefin and alcohol is not specifically limited, Usually, 20-200 degreeC, Preferably it is 40-180 degreeC, More preferably, it is 50-160 degreeC. If the reaction temperature is within this range, the reaction rate does not decrease, and there is no possibility that the solid acid catalyst is inactivated by heat.

  According to the present invention, a single or a mixture of desired cycloalkyl alkyl ethers can be produced by appropriately selecting and using one or more alicyclic olefins and alcohols.

  The method for reacting the raw material alicyclic olefin and alcohol in the presence of the solid acid catalyst is not particularly limited. For example, a solid acid catalyst is added to the raw material mixture and stirred (batch type), or the solid acid catalyst is packed in the column (hereinafter, the column packed with the solid acid catalyst is referred to as “reaction column”). A method of circulating the raw material mixture (circulation type) or the like can be used. In the present invention, it is more preferable to adopt a flow type from the viewpoint of working efficiency and continuous purification of the reaction product.

  When the batch system is adopted, a predetermined amount of solid acid catalyst, raw material alicyclic olefin and alcohol are added to the reactor, and the mixture subjected to the reaction at a predetermined temperature and a predetermined pressure is stirred. The amount of the solid acid catalyst used in this case is usually 0.01 to 200 parts by weight, preferably 0.1 to 150 parts by weight, more preferably 1 to 100 parts by weight with respect to 100 parts by weight of the raw material alicyclic olefin. Range.

  In the case of a batch type, the usage ratio of the raw material alicyclic olefin and alcohol is not particularly limited, but it is preferable to set the ratio so that the alcohol is excessive as compared with the alicyclic olefin. This is because, in the case of the batch type, the heating time of the raw material mixture becomes long, and if the reaction is carried out in an excess state of the alicyclic olefin, a polymer of the alicyclic olefin may be generated. The use ratio of the raw material alicyclic olefin and alcohol is a molar ratio (alicyclic olefin / alcohol), usually 1/1 to 1/50, preferably 1/1 to 1/30, more preferably 1. / 1-1 / 20.

  When adopting a flow type, the raw material mixture is circulated in the reaction column. In this case, a column having a heating device is used, and the mixture is circulated through the reaction column heated to a predetermined temperature (reaction temperature). Moreover, although this mixture can be distribute | circulated in a liquid state and can also be distribute | circulated in a gaseous state, in order to obtain a target object with higher selectivity, it is preferable to distribute | circulate in a gaseous state.

  When flowing through the reaction column in a gaseous state, a gas phase-solid phase reaction proceeds. As a method for carrying out this reaction, for example, as shown in FIG. 1 (a), the mixed liquid is fed from a storage tank 1a of a mixed liquid of raw material alicyclic olefin and alcohols, and then heated and vaporized apparatus 2a. The method of making this into a gaseous state and sending it into the reaction column 3a in a gaseous state is mentioned. When using a plurality of reaction columns, it is preferable to keep not only the reaction columns but also the connecting tubes connecting the reaction columns at a predetermined temperature.

  As a more specific method for carrying out the present invention by a flow equation, for example, (i) a method in which a reaction column 3a packed with a solid acid catalyst is used alone, as shown in FIG. 1 (a), (ii) FIG. 1 (b), a method in which a plurality of reaction columns 3b and 3c packed with a plurality of solid acid catalysts are connected in series to perform the reaction, (iii) as shown in FIG. Examples include a method in which the reaction columns 3d, 3e, and 3f are connected in series and in parallel to perform the reaction. When combining a plurality of reaction columns, the conversion rate of the alicyclic olefin (or alcohol) can be further improved.

  In FIG. 1B, 1b represents a storage tank that may be the same as or different from the storage tank 1a, and 2b represents a heating / vaporization device that may be the same as or different from the heating / vaporization device 2a. In FIG. 1C, 1c denotes a storage tank that may be the same as or different from the storage tank 1a, and 2c denotes a heating / vaporization device that may be the same as or different from the heating / vaporization device 2a.

  The size of the column used is not particularly limited, and various sizes can be selected and used depending on the reaction scale. When a plurality of reaction columns are used in combination, the solid acid catalyst packed in each column may be the same or different.

  Further, as a method of circulating the raw material mixture in the reaction column filled with the solid acid catalyst, for example, as shown in FIG. 1 (b), a down flow type in which the mixture is circulated from the upper part of the reaction columns 3b and 3c. Alternatively, as shown in FIG. 2, it may be an upflow type in which the mixture is circulated from the lower side of the reaction columns 3b and 3c. From the viewpoint of obtaining the desired product with a higher conversion and selectivity, the downflow method is preferred.

In the case of adopting the flow type, the pressure when the raw material mixture is passed through the reaction column is usually in the range of normal pressure (0.1 MPa) to 30 MPa, preferably normal pressure to 10 MPa, more preferably normal pressure to 5 MPa. It is. The flow rate of the raw material mixture is a liquid space velocity based on an empty column (hereinafter abbreviated as “LHSV”) if the raw material mixture is liquid, and is usually 0.01 to 100 hr ⁻¹ , preferably 0.1. in the range of ～20Hr ^1, if the raw material mixture is gaseous, the gas space velocity superficial reference (hereinafter, abbreviated as "GHSV".), the normal 0.01～40,000H ^-1, preferably 0 The range is from ¹ to 8,000 h ⁻¹ . Moreover, when using a some reaction column, reaction temperature, a distribution rate, etc. can be changed for every reaction column.

  In order to prepare the raw material mixture, the raw material alicyclic olefin and alcohols may be mixed at a predetermined ratio. In this case, a mixed liquid of raw material alicyclic olefin and alcohol can be prepared in advance, stored in a tank, and sent from the tank to the reaction column in a gaseous state or a liquid state. It is also possible to store the formula olefin and alcohol in separate tanks, feed the raw material alicyclic olefin and alcohol separately, and mix them immediately before feeding them into the reaction column.

  In the case of the flow type, the use ratio of the raw material alicyclic olefin and the alcohol is not particularly limited, but it is preferable to set the ratio so that the alicyclic olefin becomes excessive as compared with the alcohol. In the case of the flow type, the heating time of the raw material mixture is short, so that the alicyclic olefin does not polymerize. On the other hand, when alcohol is used in excess, the amount of by-produced dialkyl ether increases. The use ratio of the raw material alicyclic olefin and alcohol is usually 1 / 3-20 / 1, preferably 1 / 3-10 / 1, more preferably 1 in terms of molar ratio (alicyclic olefin / alcohol). / 3 to 5/1, more preferably 1/3 to 3/1.

  After completion of the reaction, the reaction solution can be subjected to separation and purification by known methods such as solvent extraction and distillation to isolate the target cycloalkyl alkyl ether. Distillation may be performed multiple times.

  As the distillation apparatus, for example, a known distillation apparatus such as a continuous rectification apparatus having a rectification column can be used. Also, for example, as shown in FIG. 3, after the raw material mixture was circulated through the reaction column 3g filled with the solid acid catalyst, the obtained reaction solution was passed through the reaction column 3h, for example, filled with Raschig rings. Distillation can be carried out continuously by the distillation device 4. According to this method, the unreacted alicyclic olefin and alcohol can be returned to the reaction column 3g by the pipe 5 and used again for the reaction, and the target product can be obtained at a higher conversion rate.

  In FIG. 3, 1d denotes a storage tank that may be the same as or different from the storage tank 1a, and 2d denotes a heating / vaporization device that may be the same as or different from the heating / vaporization device 2a.

The cycloalkyl alkyl ether obtained by the production method of the present invention is represented by the formula (1): R ¹ —O—R ² (wherein R ¹ has an optionally substituted cyclopentyl group or substituent. And a cycloalkyl group represented by R ² represents an alkyl group having 1 to 10 carbon atoms or a cycloalkyl group having 3 to 8 carbon atoms).

In the above formula, the substituent of the cyclopentyl group or cyclohexyl group of R ¹ is, for example, an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, An isobutyl group etc. are mentioned. Other substituents include aryl groups having 6 to 12 carbon atoms such as phenyl, xylyl, tolyl and naphthyl groups; halogen atoms such as fluorine and chlorine atoms; nitro groups; amino groups; methoxy groups and ethoxy groups. , An n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group or the like, an alkoxy group having 1 to 4 carbon atoms; a sulfonic acid group; a cyano group, or the like. The aryl group includes a heteroaromatic hydrocarbon group containing an atom other than a carbon atom such as an oxygen atom or a nitrogen atom.

The alkyl group having 1 to 10 carbon atoms of R ² may be linear or branched. For example, a methyl group (carbon number 1), an ethyl group (carbon number 2), an n-propyl group (3 carbon atoms), isopropyl group (3 carbon atoms), n-butyl group (4 carbon atoms), isobutyl group (4 carbon atoms), n-pentyl group (5 carbon atoms), n-hexyl group (6 carbon atoms) ) And the like. Moreover, as a C3-C8 cycloalkyl group, a cyclopropyl group (carbon number 3), a cyclopentyl group (carbon number 5), a cyclohexyl group (carbon number 6) etc. are mentioned, for example. Among them, R ² is preferably a linear or branched alkyl group having 1 to 6 carbon atoms, more preferably a linear or branched alkyl group having 1 to 3 carbon atoms, and particularly preferably a methyl group.

  Preferable specific examples of the cycloalkyl alkyl ether represented by the formula (1) include cyclopentyl methyl ether, cyclopentyl ethyl ether, cyclopentyl n-propyl ether, cyclopentyl isopropyl ether, cyclopentyl n-butyl ether, cyclopentyl sec-butyl ether, cyclopentyl tert. Cyclopentyl alkyl ethers such as butyl ether, cyclopentyl n-pentyl ether, dicyclopentyl ether, cyclopentyl cyclohexyl ether; cyclohexyl methyl ether, cyclohexyl ethyl ether, cyclohexyl n-propyl ether, cyclohexyl isopropyl ether, cyclohexyl n-butyl ether, cyclohexyl sec-butyl ether , Rohekishiru tert- butyl ether, cyclohexyl, n- pentyl ether, cyclohexyl cyclopropyl ether, cyclohexyl alkyl ethers such as dicyclohexyl ether, and the like.

Among these, cyclopentyl alkyl ether in which R ¹ is a cyclopentyl group is more preferable, cyclopentyl methyl ether or cyclopentyl ethyl ether is more preferable, and cyclopentyl methyl ether is particularly preferable.

  The cycloalkyl alkyl ether obtained by the production method of the present invention is a solvent for washing electronic parts and precision machine parts, a reaction solvent for various chemical reactions, an extraction solvent, a crystallization solvent, a chromatography eluent, It is useful as a solvent for electrical materials and as a release agent.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the scope of the present invention is not limited by these examples.

(1) Analysis by gas chromatography (hereinafter referred to as “GC analysis”) was performed under the following conditions.
Analytical instrument: 6850GC (manufactured by Agilent)
Column: Capillary column HP-5 30 m × φ0.25 mm (manufactured by HP)
Column temperature: 40 ° C. (10 minutes), 40 ° C. → 250 ° C. (10 ° C./min)
Inlet temperature: 200 ° C
Detector temperature: 300 ° C
Carrier gas: He
Detector: FID

(2) Cyclopentene conversion rate (hereinafter abbreviated as “CPE conversion rate”) (%) is [(number of moles of cyclopentene in 1 g of raw material liquid−number of moles of cyclopentene in 1 g of reaction liquid) / (1 g of raw material liquid]. The number of moles of cyclopentene in the middle)] × 100.
(3) Cyclopentyl methyl ether selectivity (hereinafter abbreviated as “CPME selectivity”) (%) is [(number of moles of cyclopentyl methyl ether in 1 g of reaction liquid) / (number of moles of cyclopentene in 1 g of raw material liquid]. -Number of moles of cyclopentene in 1 g of the reaction solution)] x 100.

[Production Example 1] Preparation of raw material alicyclic olefin (1)
1 L of a commercially available sulfonic acid type styrenic strongly acidic ion exchange resin (Mitsubishi Chemical Co., Ltd., trade name: RCP-160M, water content 47 wt%) is packed in a SUS column, and the column is heated to 50 ° C. 20 L of crude cyclopentene was circulated at a flow rate of 2 L / hr (LHSV = 2 hr ⁻¹ ), and cyclopentene coming out from the column outlet was cooled and condensed to be recovered. After separating and removing a partially separated aqueous layer in the recovered liquid, the remaining oil layer was subjected to atmospheric distillation with a precision distillation apparatus from which oxygen was sufficiently removed to obtain 18 L of a fraction having a boiling point of 45 ° C. Commercially available crude cyclopentene and treated cyclopentene (fraction) were each quantified for the conjugated diene compound contained by GC analysis. As a result, the content of 1,3-pentadiene was about 3000 ppm in the crude cyclopentene and 4 ppm in the treated cyclopentene. On the other hand, the content of cyclopentadiene was about 300 ppm in the crude cyclopentene and 9 ppm in the treated cyclopentene.

[Production Example 2] Preparation of raw material alicyclic olefin (2)
Commercially available crude cyclopentene 20 L, 20 g of 5% palladium carbon were charged into a reactor, and hydrogen was introduced at room temperature while stirring. After the reaction for 6 hours, the reaction solution was filtered and oxygen was sufficiently removed with a precision distillation apparatus, and atmospheric distillation was performed to obtain 16 L of a fraction having a boiling point of 47 ° C. Crude cyclopentene and treated cyclopentene (fraction) were each quantified for the conjugated diene compound contained by GC analysis. As a result, the content of 1,3-pentadiene was about 3000 ppm in the crude cyclopentene and 3 ppm in the treated cyclopentene. On the other hand, the content of cyclopentadiene was about 300 ppm in the crude cyclopentene and about 200 ppm in the treated cyclopentene.

[Production Example 3] Dehydration of acidic ion exchange resin 500 mL of a commercially available sulfonic acid type styrene strongly acidic ion exchange resin (manufactured by Mitsubishi Chemical Co., Ltd., trade name: RCP-160M, water content 47% by weight) was packed in a glass column, The ion exchange resin was washed by flowing 5 L of dehydrated methyl alcohol having a water content of 50 ppm through the glass column in a down flow at a flow rate of ¹ L / hr (LHSV = 2 hr ⁻¹ ). Furthermore, 1 L of pure nitrogen was circulated through the glass column in a down flow to remove methyl alcohol remaining between the resin particles. The water content of the dehydrated ion exchange resin was measured by Karl Fischer coulometric titration and found to be 1.8% by weight. The acidic ion exchange resin thus obtained (hereinafter referred to as “dehydrated acidic ion exchange resin”) was used in the reaction.

  The water content was measured by the Karl Fischer coulometric titration method using a Hiranuma moisture measuring device (product number: AQ-7, manufactured by Hiranuma Sangyo Co., Ltd.), and Hydranal (R) and Aqualite (RS- A) (the generated solution is manufactured by Sigma-Aldrich), and Aqualite (CN) (the counter electrode solution is manufactured by Kanto Chemical Co., Inc.) was used as the counter electrode solution.

[Example 1]
Example 1 was performed using the reaction apparatus shown in FIG. The reaction column 3a made of SUS was filled with the dehydrated acidic ion exchange resin obtained in Production Example 3, and the column 3a was kept at 90 ° C.

On the other hand, a mixture of the treated cyclopentene (1,3-pentadiene content 4 ppm, cyclopentadiene content 9 ppm) obtained in Production Example 1 and methanol (mixing molar ratio: cyclopentene / methanol = 1.6 / 1, below) The reaction column 3a is fed from the tank 1a, heated and vaporized to 80 ° C. by the heating / vaporization apparatus 2a, and kept at 90 ° C. at normal pressure and GHSV = 200 hr ^−1. I sent it continuously inside. The liquid flowing out from the outlet of the reaction tube (hereinafter referred to as “reaction liquid”) is cooled and condensed with dry ice-methanol, and the reaction liquid is passed after 20 hours, 200 hours, 400 hours and 600 hours from the start of the reaction. GC analysis was performed. The results are shown in Table 1.

[Comparative Example 1]
The reaction was carried out in the same manner as in Example 1 except that the treated cyclopentene obtained in Production Example 2 (1,3-pentadiene content 3 ppm, cyclopentadiene content about 200 ppm) was used as the treated cyclopentene. The results are shown in Table 1.

[Comparative Example 2]
Instead of the treated cyclopentene, commercially available crude cyclopentene (1,3-pentadiene content of about 3000 ppm, cyclopentadiene content of about 300 ppm) was used, and the reaction was stopped in 200 hours from the start of the reaction. The reaction was performed. The results are shown in Table 1.

  From the comparison between Example 1 and Comparative Examples 1 and 2 in Table 1, when the reaction was carried out using the treated cyclopentene in which the contents of 1,3-pentadiene and cyclopentadiene were both 10 ppm or less, the reaction time was 200 hours or more. It can be seen that the catalytic activity does not substantially decrease even when continuous operation is performed for a long time.

Claims (4)

  A method for producing a cycloalkyl alkyl ether comprising a step of reacting a raw material alicyclic olefin having a chain conjugated diene compound content and a cyclic conjugated diene compound content of 10 ppm or less with an alcohol in the presence of a solid acid catalyst.   The production method according to claim 1, wherein the solid acid catalyst is an acidic ion exchange resin.   The production method according to claim 1 or 2, wherein the chain conjugated diene compound is 1,3-pentadiene and the cyclic conjugated diene compound is cyclopentadiene.   The production method according to any one of claims 1 to 3, wherein cyclopentyl methyl ether is produced.

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