JP2002069009A - Method for continuously producing ethylidenetetracyclododecene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing high-purity ethylidenetetracyclododecene(EdTCD) in high yield through mixing under heating 5-ethylidene-2-norbornene (EBH) and cyclopentadiene and/or dicyclopentadiene, wherein unreacted EBH is recovered and circulated in high purity and reused. SOLUTION: The objective method for producing EdTCD comprises the following practice: at least part of 5-ethylidene-2-methyl-2-norbornene (E2MBH) or 5-ethylidene-3-methyl-2-norbornene (E3MBH) contained in EBH as one of the raw materials is separated and eliminated from EBH to be recovered, circulated and reused to specify the amount of E2MBH or E3MBH based on the total amount of EBH to be reused and newly fed EBH so as to prevent E2MBH or E3MBH from accumulation in the reaction system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to ethylidenetetracyclododecene (hereinafter sometimes referred to as EdTCD).
Related to the manufacturing process. Specifically, 5-ethylidene-
2-norbornene (hereinafter sometimes referred to as EBH)
The present invention relates to a method for producing EdTCD, in which a Diels-Alder reaction is carried out between EBH and cyclopentadiene, and unreacted EBH is recovered, circulated and reused with high purity.

[0002]

2. Description of the Related Art In recent years, attention has been paid to cycloolefin (co) polymers having excellent optical properties, high transparency, heat resistance and oil absorption properties, and they are produced by polymerization of cyclic olefins with an organometallic complex catalyst. . Therefore, a cyclic olefin represented by tetracyclododecene is extremely useful as a raw material for a cycloolefin (co) polymer. EdTCD is one of cyclic olefins, and various production methods have been disclosed. JP-A-47-3197
No. 0, EBH and cyclopentadiene (hereinafter referred to as C
A method for producing EdTCD by heating and mixing of PDC (hereinafter sometimes referred to as PD) and / or dicyclopentadiene (hereinafter sometimes referred to as DCPD) is disclosed. JP-A-63-203635 discloses 5-vinyl-2-
Norbornene (hereinafter sometimes referred to as VBH) and C
A method for producing EdTCD, in which PD and / or DCPD is heated and mixed at 120 ° C. or higher, and an addition reaction and an olefin isomerization reaction are simultaneously performed,
There is a description that it is preferable to remove vinylcyclohexene and tetrahydroindene (hereinafter, sometimes referred to as THI) contained as impurities in VBH because the product is easily purified.

[0003] In the production of EdTCD, a method of circulating and recycling the raw material components present in the reaction mixture is effective from the viewpoint of high yield, low cost, waste disposal, and the like.
When EBH is used as a raw material and is recycled and reused, 5-ethylidene-
3-methyl-2-norbornene and 5-ethylidene-2-
Methyl-2-norbornene may have an adverse effect. That is, since these impurities are tri-substituted olefins in the norbornene moiety, these impurities are the
Since the Alder reactivity is low and the boiling point is close to that of EBH, separation is difficult, and there is a possibility that it is mixed in EBH to be recycled and accumulated in the system. Furthermore, it is inevitable that the amount of these impurities accumulated in the reaction system increases due to the new supply of EBH.

Until now, EdTCD using EBH as a raw material
In the production method of the above, when recycling unreacted EBH, there is no risk of accumulating impurities such as 5-ethylidene-3-methyl-2-norbornene and 5-ethylidene-2-methyl-2-norbornene. The method was not shown.

[0005]

SUMMARY OF THE INVENTION The present invention relates to EBH and C
EdTC by heat mixing of PD and / or DCPD
An object of the present invention is to provide a process in which unreacted EBH is recovered and circulated in high purity in the production of D, reused as a raw material again, and high-purity EdTCD can be obtained in high yield.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems, and comprises the following steps (1) to (4): ethylidenetetracyclo represented by the following formula [4]: It is a continuous production method of dodecene. (1) As impurities, 5-ethylidene-2-methyl-2-norbornene represented by the following formula [1] and / or 5-ethylidene-3-methyl-2 represented by the following formula [2]
5-ethylidene-2-norbornene represented by the following formula [3] containing -norbornene and cyclopentadiene and / or dicyclopentadiene are supplied to a reactor to be reacted, and at least ethylidene represented by the following formula [4] Producing a reaction mixture containing tetracyclododecene,

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Embedded image (2) From the reaction mixture obtained in the step (1), 5-
5-ethylidene-2 in which at least a part of ethylidene-2-methyl-2-norbornene and / or 5-ethylidene-3-methyl-2-norbornene is separated and removed
-A step of separating and recovering norbornene, (3) a step of circulating at least a part of the 5-ethylidene-2-norbornene separated and recovered in the step (2) to the reactor, (4) the step (3). Separating and recovering ethylidenetetracyclododecene from the reaction mixture.

According to the method of the present invention, at least a part of 5-ethylidene-2-methyl-2-norbornene and / or 5-ethylidene-3-methyl-2-norbornene contained in the raw material EBH is recovered. Separation and removal from the EBH to be recycled and reused, these impurities are prevented from accumulating in the reaction system, and as a result, EdT
CD can be obtained with high purity, and continuous stable operation can be performed. is there.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The EBH used as a raw material in the present invention is industrially produced by isomerizing VBH, a Diels-Alder reaction adduct of butadiene and CPD, from a terminal olefin to an internal olefin with a strong base. In this case, industrial DCPD is used as the raw material of CPD, and DCPD contains an adduct of methylcyclopentadiene and CPD. Therefore, VBH
It contains a Diels-Alder reaction adduct of methylcyclopentadiene and butadiene (hereinafter sometimes referred to as MeEBH), and is also contained in EBH.
Note that EBH has two types of isomers, and any of them can be used.

MeEBH includes 5-ethylidene-2-methyl-2-norbornene represented by the formula [1] and 5-ethylidene-3-methyl-2-norbornene represented by the formula [2]. There are 6-ethylidene-1-methyl-2-norbornene represented by the formula [5] and 5-ethylidene-1-methyl-2-norbornene represented by the following formula [6].

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Embedded image MeEBH represented by the formulas [5] and [6] has a disubstituted olefin at the norbornene moiety,
Since the alder reactivity is equivalent to EBH, it is not consumed in the reaction and remains in the reaction system. However, MeEBH represented by the formulas [1] and [2] has trisubstitution of the olefin at the norbornene moiety, has lower Diels-Alder reactivity than EBH, and remains in the reaction system without being consumed in the reaction.

In the present invention, EBH as a raw material is supplied to a reactor, and EBH remaining in the reaction solution is separated, recovered, circulated and reused. MeEBH represented by the formula [2]
EBH recovered, circulated, and reused because H and boiling point are close
Easy to mix into If the EBH is mixed with the EBH to be recovered and circulated, the EBH accumulates in the reaction system.

In order to completely separate MeEBH and EBH, it is necessary to increase the reflux ratio or use a high-column column, but these methods are not industrially advantageous.
In the present invention, utilizing the fact that MeEBH has a higher boiling point than EBH, it is represented by the formulas [1] and [2] from EBH that is collected and recycled for use by leaving it in the distillation bottom together with a part of EBH. Most of the MeEBH can be separated. At this time, the EBH circulating more than the amount of MeEBH newly generated from the EBH supplied to the reaction system
It is important to separate them from the system and discharge them out of the system. Also M
eEBH is discharged out of the system together with at least one component selected from EBH, DCPD, methyl tetrahydroindene described below (hereinafter sometimes referred to as MeTHI), and EdTCD.

Further, MeEBH may generate by-products due to an addition reaction with CPD or the like. As described above, MeEBH represented by the formulas [1] and [2] has a Diels-Alder reactivity. Since it is low, if the amount present in the system is small, the proportion of by-products formed is small, and this does not pose a major problem. Of course, the production ratio of by-products varies depending on the reaction temperature and the residence time.
As long as the purity of D is not affected, there is no problem even if MeEBH represented by Formula [1] and Formula [2] is present in EBH. As such a concentration of MeEBH,
It is at most 10%, preferably at most 5%, more preferably at most 3%, based on the total of EBH supplied to the reaction system and EBH recovered, circulated and reused.

In the present invention, cyclopentadiene and / or dicyclopentadiene are used as raw materials in addition to EBH. As CPD, DCPD obtained by subjecting DCPD to pyrolysis distillation in advance is preferable. Further, under normal reaction conditions in the present invention, CPD is generated by thermal decomposition of DCPD, so that DCPD can be used as it is. DCPD is preferably recovered from pyrolysis oil such as naphtha because it is industrially produced in large quantities, easily available, and inexpensive. However, commercial products often contain impurities such as MeTHI, so be careful. Is essential.

When DCPD containing MeTHI or (iso) propylidene norbornene is used, (iso) propylidene norbornene isomerized to MeTHI by heat. Since MeTHI has low Diels-Alder reactivity, it tends to remain and accumulate in the reaction solution. Therefore, the reaction solution and the recovery, M
It is preferable to separate and remove eTHI, and it is very preferable to separate eTHI simultaneously with MeEBH represented by the above formulas [1] and [2].

In the present invention, a reaction mixture of EBH and CPD and / or DCPD is produced (step (1)). At this time, the molar ratio of EBH / DCPD (converted to DCPD when CPD is partially or entirely used) is 0.1 to 20, preferably 0.5 to 17, and more preferably 1 to 15. If the value is smaller than the lower limit, a large amount of by-products such as heavy components are generated.
The dTCD generation efficiency is reduced.

[0016] The reaction temperature is 100 to 300 ° C, preferably 120 to 280 ° C, more preferably 140 to 270 ° C. When the temperature is lower than the lower limit, the dissociation into CPD is reduced when DCPD is used, so that the production efficiency of EdTCD decreases. At a temperature higher than the upper limit, an increase in the amount of heavy components and the like and decomposition of EdTCD occur. The reaction pressure is normal pressure to 10 MPa, preferably normal pressure to 8 MPa, more preferably normal pressure to 5 MPa.

[0017] The residence time is 1 minute to 24 hours, preferably 10 minutes to 12 hours, more preferably 15 minutes to 2 hours in both the batch type and the continuous type. If the time is shorter than the lower limit, the production efficiency of EdTCD becomes low, and if the time is longer than the upper limit, an increase in heavy components and decomposition of EdTCD occur, which is not preferable.

As the reactor, either a complete mixing type or a piston flow type can be used. As the piston flow type reactor, commercially available "Static Mixer" manufactured by Noritake Company, Ltd., "Sluzer Mixer" manufactured by Sumitomo Heavy Industries, Ltd., "Skeya Mixer" manufactured by Sakura Seisakusho Co., Ltd.
And the like. The reactor may have a single-stage structure or a multi-stage structure of two or more stages. When the reactor is operated in multiple stages, a completely mixed type or a piston flow type reactor may be used in combination in series or in parallel.

The reaction mixture is continuously withdrawn from the reactor and then led to a distillation step. First, isoprene, piperylene, and the like derived from impurities of CPD and / or DCPD generated in the reaction are extracted from the top of the distillation column and separated. This step is an optional step, and the following EBH separation and recovery steps are performed. At the same time. The separation here is performed at a pressure of about 10 to 500 kPa, and a distillation column may be used or only flashing may be performed.
The CPD separated here can be reused as a raw material. The liquid obtained from the bottom of this column is sent to the next distillation column.

Next, the process proceeds to the step (2) of separating and collecting EBH. Here, EBH separated from at least a part of MeEBH represented by the formulas [1] and [2] present in the reaction solution is extracted from the tower top and collected. The separation here is performed at a pressure of about 1 kPa to normal pressure, and the collected EB
H is circulated and reused (step (3)). As described above, when there is no step of extracting isoprene or the like, CPD, isoprene, piperylene and the like are extracted together with EBH from the top of the column. Alternatively, CPD, isoprene, and piperylene are extracted from the top of the column, and EBH is more concentrated in the middle of the distillation column.
May be extracted. In any case, the MeEBH content represented by the formulas [1] and [2] in the EBH separated and recovered here is the sum of the EBH recycled and reused and the EBH newly supplied. On the other hand, it is important that the content be 10% or less, preferably 5% or less, more preferably 3% or less. The liquid obtained from the bottom of this column is sent to the next distillation column.

Next, a step of separating and removing MeEBH represented by the formulas [1] and [2] and DCPD and / or MeTHI present in the reaction solution is started. This step is also an optional step. They are withdrawn from the top at a pressure of 0.1-100 kPa. Alternatively, MeEBH represented by the formulas [1] and [2] may be extracted from the top of the tower, and DCPD and / or MeTHI may be extracted from the tower. The liquid obtained from the bottom of this column is sent to the next distillation column.

In the case where the above-mentioned step is present, 0.01 to 10
At 0 kPa, the target EdTCD is extracted from the top of the tower (step (4)). In the absence of the above step, MeEBH and DC represented by the formulas [1] and [2] are added from the top of the column.
PD and / or MeTHI are extracted, and EdTCD is extracted and recovered from the middle of the distillation column (step (4)).

In each distillation column, various packings can be packed or refluxed in order to increase the separation efficiency.
The number of theoretical plates is 1 to 100, preferably 2 to 50, and more preferably 3 to 30. The reflux ratio is determined depending on the separation state of each distillation column, but is suitably 1 to 50.

In the present invention, a hydrocarbon compound can be used as a reaction solvent. Although aromatic hydrocarbons such as benzene, toluene and xylene can be used,
An alicyclic hydrocarbon or a branched aliphatic hydrocarbon is preferably used because of its high safety to the environment and the human body and high solubility. Specifically, cyclopentane, cyclohexane, ethylcyclopentane, dimethylcyclopentane, methylcyclohexane, normal hexane, normal heptane, 2-methylhexane, 3-methylhexane, 3-ethylpentane, 2,3-dimethylpentane,
Examples include 3,3-dimethylpentane, normal octane, methylheptane, dimethylhexane, 2,2,3-trimethylpentane, 2,2,4-trimethylpentane, normal decane, alkylate gasoline and the like. Alkylated gasoline is a product obtained by alkylating isobutane with butene using a (super) strong acid such as zirconia sulfate, sulfuric acid, and hydrogen fluoride as a catalyst. It is. By using these solvents, it is possible to achieve a condition in which substantially no gas phase exists at a low pressure.
It is also possible to improve the yield of D. The amount of the hydrocarbon solvent used is arbitrary, but is preferably in a range where the molar ratio of (total of EBH to be recycled and reused and EBH to be newly supplied) / (hydrocarbon solvent) is from 0.1 to 10.

In the present invention, an antioxidant and a polymerization inhibitor can be appropriately added to the raw materials. For example, phenolic compounds such as hydroquinone, 2,6-di-t-butylphenol, 2,6-di-t-butyl-p-cresol, 4-methoxyphenol, N, N-dimethylhydroxylamine, N, N- A hydroxylamine compound such as diethylhydroxylamine is preferably used. The addition amount is usually 10 to 10,000 ppm, preferably 50 to 5,000 ppm, based on the total amount of the raw materials supplied into the reactor. Of course, they can also be added to EdTCD as a product.

[0026]

The present invention will be described below with reference to examples. Example 1 Continuous production of ethylidenetetracyclododecene was carried out using the apparatus shown in FIG. EBH and DCPD are supplied from a EBH tank 1 and a DCPD tank 2 to a reactor 4 by a transfer pump 3. At this time, the reaction was carried out by continuously charging the reactor 4 while mixing 1 mol of DCPD with respect to a total of 10 mol of the circulating EBH and the newly supplied EBH. The newly supplied EBH had a purity of 99.3% and contained 1,000 ppm of 5-ethylidene-2-methyl-2-norbornene and 5-ethylidene-3-methyl-2-norbornene. Also, D
CPD was 95.5% pure and contained 0.2% (iso) propenylnorbornene and MeTHI. Space velocity is 2 h ⁻¹ , reaction temperature is 230 ° C., reaction pressure is 5 M
It was operated continuously as Pa. The first distillation column 5 has a theoretical plate number of 20 and has a pressure of 100 kPa from the top of the column.
The component mainly composed of D was continuously extracted and separated. First
The mixed liquid extracted from the bottom of the distillation column 5 was treated with 30 theoretical plates.
Sent to the second distillation column 6 at the stage, and EB
H was recovered. The purity of this EBH is 99.5%,
5-ethylidene-2-methyl-2-norbornene and 5-ethylidene-3-methyl-2-norbornene are 10
0 ppm was contained. The EBH collected here is mixed with EBH and DCPD newly supplied from the EBH tank 1 and the DCPD tank 2 through the circulation line 9 and supplied to the reactor 4 by the transfer pump 3. The mixed liquid extracted from the bottom of the second distillation column 6 is sent to a third distillation column 7 having 30 theoretical plates, and continuously operated at a pressure of 3 kPa, and 5-ethylidene-2-methyl-2 is supplied from the top of the column. A fraction mainly composed of -norbornene, 5-ethylidene-3-methyl-2-norbornene and MeTHI was continuously extracted and removed. The obtained 5-ethylidene-2-methyl-2-norbornene and 5-ethylidene-3-methyl-2-norbornene were in amounts corresponding to VBH contained in newly supplied EBH. The mixed liquid extracted from the bottom of the third distillation column 7 is sent to a fourth distillation column 8 having 30 theoretical plates, and is continuously operated at a pressure of 2 kPa, and ethylidenetetracyclo having a purity of 99.3% is obtained from the top of the column. Dodecene was continuously withdrawn and collected. The conversion of DCPD was 99%, and the selectivity of ethylidenetetracyclododecene was 97%.

(Comparative Example 1) In Example 1, 5-ethylidene-2-methyl-2-norbornene and 5-ethylidene-2-methyl-2-norbornene were used in the EBH for circulation separated in the second distillation column without using the third distillation column. Example 1 was repeated except that ethylidene-3-methyl-2-norbornene was included.
In the reactor, 5-ethylidene-3-methyl-2-norbornene and 5-ethylidene-3-methyl-2-norbornene accumulated, and their concentrations increased with the elapse of the operation time. At the same time, a decrease in the purity of ethylidenetetracyclododecene was observed.

[0028]

According to the method for producing ethylidenetetracyclododecene of the present invention, EB to be recovered, circulated and reused is used.
By defining the amounts of 5-ethylidene-2-methyl-2-norbornene and 5-ethylidene-3-methyl-2-norbornene with respect to the sum of H and newly supplied EBH, highly pure ethylidenetetracyclo Dodecene can be obtained.

[Brief description of the drawings]

FIG. 1 is a process chart showing an example of the method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 EBH tank 2 DCPD tank 3 Transfer pump 4 Reactor 5 1st distillation column 6 2nd distillation column 7 3rd distillation column 8 4th distillation column 9 Collection and circulation line

Claims (1)

[Claims] 1. A method for continuously producing ethylidenetetracyclododecene represented by the following formula [4], comprising the following steps (1) to (4). (1) As impurities, 5-ethylidene-2-methyl-2-norbornene represented by the following formula [1] and / or 5-ethylidene-3-methyl-2 represented by the following formula [2]
5-ethylidene-2-norbornene represented by the following formula [3] containing -norbornene and cyclopentadiene and / or dicyclopentadiene are supplied to a reactor to be reacted, and at least ethylidene tetra represented by the following formula [4] is obtained. Producing a reaction mixture containing cyclododecene, Embedded image Embedded image Embedded image (2) From the reaction mixture obtained in the step (1), 5-
5-ethylidene-2 in which at least a part of ethylidene-2-methyl-2-norbornene and / or 5-ethylidene-3-methyl-2-norbornene is separated and removed
-A step of separating and recovering norbornene, (3) a step of circulating at least a part of the 5-ethylidene-2-norbornene separated and recovered in the step (2) to the reactor, (4) the step (3). Separating and recovering ethylidenetetracyclododecene from the reaction mixture.