JP2017160378A - Method for reducing amount of solid phase consisting of crystalline cyclic olefin polymer hydride and method for cleaning reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for reducing the amount of a solid phase in a solid liquid 2 phase system consisting of a liquid phase containing a solvent and the solid phase containing a crystalline cyclic olefin polymer hydride which is hardly soluble in the solvent and a method for cleaning a reactor using the method for reducing the amount of the solid phase.SOLUTION: There are provided a method for reducing the amount of a solid phase in a solid liquid 2 phase system of a liquid phase containing a solvent and the solid phase consisting of a crystalline cyclic olefin polymer hydride which is hardly soluble in the solvent, by contacting the crystalline cyclic olefin polymer hydride constituting the solid phase with hydrogen in presence of a metal or a metal compound and a method for cleaning a reactor using the method.SELECTED DRAWING: None

Description

  The present invention relates to a method for reducing the amount of the solid phase in a solid-liquid two-phase system comprising a liquid phase containing a solvent and a solid phase composed of a hydride of a crystalline cyclic olefin polymer that is hardly soluble in the solvent, and this The present invention relates to a method for washing a reactor using a method for reducing the amount of solid phase.

The crystalline cyclic olefin polymer hydride can be produced by hydrogenating the cyclic olefin polymer.
For example, Patent Document 1 describes a step of obtaining a ring-opened polymer by solution polymerization of a norbornene monomer using a specific polymerization catalyst, and a main chain double bond of the obtained ring-opened polymer. A method for producing a cyclic olefin polymer hydride comprising a hydrogenation step is described. Patent Document 1 also describes that a crystalline cyclic olefin polymer hydride having a syndiotactic structure can be obtained by using the production method.

JP 2006-052333 A

Crystalline cyclic olefin polymer hydrides tend to have poor solubility in common solvents. For this reason, in the manufacturing method described in Patent Document 1, a crystalline cyclic olefin polymer hydride is usually deposited as the hydrogenation reaction proceeds. And the target object is isolated by taking out the crystallized cyclic olefin polymer hydride from the reactor.
A portion of the precipitated crystalline cyclic olefin polymer hydride may adhere to the reactor as a scale, and may remain in the reactor even after the crystalline cyclic olefin polymer hydride is taken out. .
Therefore, in order to remove the crystalline cyclic olefin polymer hydride adhering as a scale in the reactor, the scale remaining in the reactor is removed by using a method such as a high pressure washing method or an ultrasonic washing method. There was a need.
However, when the reactor is washed by these methods, it is necessary to open the reactor to perform the work, which causes a problem in terms of efficiency. Furthermore, in the high-pressure cleaning method, if the reactor is equipped with an apparatus having a complicated shape such as an internal coil, the number of dead spots increases, and the reactor may not be sufficiently cleaned. Further, in the ultrasonic cleaning method, erosion occurs due to cavitation, which may damage the reactor.
For this reason, there has been a demand for a method that can easily remove the scale adhering to the reactor and efficiently wash the reactor.

  The present invention has been made in view of the above situation, and in a solid-liquid two-phase system comprising a liquid phase containing a solvent and a solid phase comprising a crystalline cyclic olefin polymer hydride that is hardly soluble in the solvent, It is an object of the present invention to provide a method for reducing the amount of the solid phase and a method for washing a reactor using the method for reducing the amount of the solid phase.

  In order to solve the above-mentioned problems, the present inventor, in a solid-liquid two-phase system comprising a liquid phase containing a solvent and a solid phase comprising a crystalline cyclic olefin polymer hydride hardly soluble in the solvent, the amount of the solid phase The method to reduce the amount of intensively studied. As a result, it was found that the amount of the solid phase can be reduced by bringing a crystalline cyclic olefin polymer hydride that is hardly soluble in the solvent into contact with hydrogen in the presence of a metal or a metal compound. The present invention has been completed.

Thus, according to the present invention, there are provided the following methods [1] to [6] for reducing the amount of solid phase and [7] and [8] for washing the reactor.
[1] A method for reducing the amount of solid phase in a solid-liquid two-phase system of a liquid phase containing a solvent and a solid phase comprising a crystalline cyclic olefin polymer hydride that is hardly soluble in the solvent,
A method for reducing the amount of solid phase in a solid-liquid two-phase system, characterized in that the crystalline cyclic olefin polymer hydride constituting the solid phase is brought into contact with hydrogen in the presence of a metal or a metal compound.
[2] The method for reducing the solid phase amount according to [1], wherein the solvent is a cycloalkane solvent.
[3] The method for reducing the solid phase amount according to [1] or [2], wherein the solubility of the crystalline cyclic olefin polymer hydride in the solvent at 40 ° C. is 1 g / 100 g (solvent) or less.
[4] The method for reducing the solid phase amount according to any one of [1] to [3], wherein the metal or metal compound catalyzes an isomerization reaction of a crystalline cyclic olefin polymer hydride.
[5] The method for reducing the solid phase amount according to any one of [1] to [4], wherein the metal or metal compound is metal nickel or a nickel compound.
[6] The hydrogen pressure when the crystalline cyclic olefin polymer hydride is brought into contact with hydrogen is 3.0 to 7.0 MPa, and the reaction temperature is 200 to 250 ° C. [1] to [5] The method for reducing the amount of solid phase according to any one of the above.
[7] A method for washing a reactor in which a crystalline cyclic olefin polymer hydride is adhered as a scale, and a solvent is put into the reactor, and a liquid phase containing the solvent and a poorly soluble in the solvent A solid-liquid two-phase system with a solid phase made of a crystalline olefin polymer hydride of the above, and the amount of the solid phase constituting the solid-liquid two-phase system is any one of [1] to [6] A method for cleaning a reactor, characterized in that it is reduced by using the method.
[8] The scale attached to the reactor is produced by a hydrogenation reaction of a cyclic olefin polymer, and the same solvent as the solvent used in the hydrogenation reaction of the cyclic olefin polymer is used as the solvent. The method for cleaning a reactor according to [7], which is used.

  According to the present invention, in a solid-liquid two-phase system of a liquid phase containing a solvent and a solid phase made of a hydrated crystalline cyclic olefin polymer that is hardly soluble in the solvent, the amount of the solid phase is efficiently reduced. A method for reducing the amount of solid phase and a method for washing a reactor using the method for reducing the amount of solid phase are provided.

  Hereinafter, the present invention will be described in detail by dividing it into 1) a method for reducing the amount of solid phase and 2) a method for washing the reactor.

1) Method for reducing the amount of solid phase The method for reducing the amount of solid phase according to the present invention comprises a solid-liquid 2 comprising a liquid phase containing a solvent and a solid phase comprising a hydride of a crystalline cyclic olefin polymer that is hardly soluble in the solvent. A method for reducing the amount of the solid phase in a phase system, wherein the crystalline cyclic olefin polymer hydride constituting the solid phase is brought into contact with hydrogen in the presence of a metal or a metal compound. And

[Liquid phase]
The liquid phase constituting the solid-liquid two-phase system contains a solvent.
The solvent contained in the liquid phase is not particularly limited as long as it is difficult to dissolve the crystalline cyclic olefin polymer hydride. In general, a crystalline cyclic olefin polymer hydride tends to be inferior in solubility in a general solvent. Therefore, in the present invention, a general-purpose solvent used for chemical synthesis, washing, or the like can be used without particular limitation. it can.

Examples of such solvents include alkane solvents such as pentane, hexane, heptane, octane, nonane, decane; cyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane, dimethylcyclohexane, diethylcyclohexane, trimethylcyclohexane, cycloheptane, cyclooctane, decalin, Cycloalkane solvents such as norbornane, methylnorbornane, ethylnorbornane; aromatic hydrocarbon compounds such as benzene, toluene, xylene, ethylbenzene, cumene; chlorobutane, bromohexane, methylene chloride, dichloroethane, hexamethylene dibromide, chlorobenzene, Halogenated hydrocarbon compound solvents such as chloroform and tetrachloroethylene; and the like.
Among these, when the method of the present invention is used for a washing method such as a reactor, a cycloalkane solvent is preferable because the washing operation can be performed more efficiently and the used washing solvent can be efficiently removed. Cyclohexane or decalin is more preferable, and cyclohexane is particularly preferable.
These solvents can be used alone or in combination of two or more.

Although the quantity of a solvent is not specifically limited, It is 1000-10000 weight part normally with respect to 100 weight part of crystalline cyclic olefin polymer hydrides, Preferably it is 3000-5000 weight part.
When there is too little solvent, the fluidity | liquidity of the solution or suspension obtained after a process becomes low, and there exists a possibility that it may take time for these transfer operations. On the other hand, if there are too many solvents, it may be unpreferable from an efficiency viewpoint.

[Solid phase]
The solid phase constituting the solid-liquid two-phase system is composed of a crystalline cyclic olefin polymer hydride (hereinafter sometimes referred to as “polymer (α)”) that is hardly soluble in the solvent.
In the present invention, “slightly soluble” means that the solubility of the crystalline cyclic olefin polymer hydride in the solvent is small enough to form a solid-liquid two-phase system.
The solubility of the polymer (α) in the solvent at 40 ° C. is preferably 1 g / 100 g (solvent) or less, more preferably 0.2 g / 100 g (solvent) or less.

The polymer (α) is a cyclic olefin polymer hydride having crystallinity.
In the present invention, the “polymer having crystallinity” means a polymer whose melting point is observed by a differential scanning calorimeter (DSC).
The melting point of the polymer (α) is preferably 200 ° C. or higher, more preferably 230 to 290 ° C.

Cyclic olefin polymer hydride is a hydride of a polymer having an alicyclic structure in the molecule (hereinafter sometimes referred to as “cyclic olefin polymer”) obtained by polymerizing a cyclic olefin monomer. It is.
Examples of the alicyclic structure that the cyclic olefin polymer has include a cycloalkane structure and a cycloalkene structure. Among these, a cycloalkane structure is preferable because it easily becomes a cyclic olefin polymer having excellent transparency, light resistance, durability, and the like. The number of carbon atoms constituting the alicyclic structure is not particularly limited, but is usually 4 to 30, preferably 5 to 20, and more preferably 5 to 15.

Although the weight average molecular weight (Mw) of a cyclic olefin polymer is not specifically limited, Usually, 10,000-1,000,000, Preferably, it is 10,000-500,000. Such a polymer having a weight average molecular weight is preferably used as a molding material for various resin moldings.
The molecular weight distribution (Mw / Mn) of the cyclic olefin polymer is not particularly limited, but is usually 4.0 or less, preferably 3.5 or less. A polymer having such a molecular weight distribution is more excellent in moldability.
The weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn) of the cyclic olefin polymer are standard polystyrene conversion values measured by gel permeation chromatography (GPC) using tetrahydrofuran as a developing solvent.

  Examples of the cyclic olefin polymer include a ring-opening polymer of a cyclic olefin monomer (hereinafter sometimes referred to as “polymer (β)”).

  The cyclic olefin monomer used for production of the polymer (β) is a compound having a ring structure formed of carbon atoms and having a carbon-carbon double bond in the ring. Specific examples include norbornene monomers. When the polymer (β) is a copolymer, a monocyclic olefin monomer can be used as the cyclic olefin monomer.

The norbornene monomer is a monomer containing a norbornene ring.
The norbornene-based monomer includes bicyclo [2.2.1] hept-2-ene (common name: norbornene), 5-ethylidene-bicyclo [2.2.1] hept-2-ene (common name: ethylidene). Norbornene) and derivatives thereof (those having a substituent in the ring);
Tricyclic monomers such as tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene (common name: dicyclopentadiene) and derivatives thereof;
7,8-tricyclo [4.3.0.1 ^{2, 5]} dec-3-ene (common name: methanolate tetrahydrofluorene, tetracyclo ^[7.4.0.0 2,7 ^{.1 10,13]} Trideca-2,4,6,11-tetraene) and its derivatives, tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene (common name: tetracyclododecene), 8-ethylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene and tetracyclic monomers such as derivatives thereof; and the like.

  These monomers may have a substituent at an arbitrary position. Examples of the substituent include alkyl groups such as methyl group and ethyl group; alkenyl groups such as vinyl group; alkylidene groups such as ethylidene group and propane-2-ylidene group; aryl groups such as phenyl group; hydroxy group; Group; carboxyl group; alkoxycarbonyl group such as methoxycarbonyl group; and the like.

  Monocyclic olefin monomers include cyclobutene, cyclopentene, methylcyclopentene, cyclohexene, methylcyclohexene, cycloheptene, cyclooctene, and other cyclic monoolefins; cyclohexadiene, methylcyclohexadiene, cyclooctadiene, methylcyclooctadiene, phenyl Cyclic diolefins such as cyclooctadiene; and the like.

  Among these, it is preferable to use dicyclopentadiene as at least one cyclic olefin monomer when producing the polymer (β) because a polymer (α) having better crystallinity is easily obtained. The content of the repeating unit derived from dicyclopentadiene is preferably 50% by weight or more, more preferably 70% by weight or more, still more preferably 90% by weight or more, further preferably 100%, in all repeating units of the polymer (β). % By weight.

  Some cyclic olefin monomers include stereoisomers of endo and exo, both of which can be used as monomers when producing the polymer (β). Moreover, only one isomer may be used alone, or an isomer mixture in which an endo isomer and an exo isomer are present in an arbitrary ratio may be used. Since the polymer (α) having better crystallinity is easily obtained, it is preferable to increase the ratio of one stereoisomer. For example, the ratio of endo-form or exo-form is preferably 80% or more, more preferably 90% or more, and still more preferably 95% or more. In addition, since the synthesis | combination is easy, it is preferable that the ratio of an end body is high.

The said cyclic olefin monomer can be used individually by 1 type or in combination of 2 or more types.
When two or more cyclic olefin monomers are used, the polymer (β) may be a block copolymer or a random copolymer.

The polymer (β) can be produced according to a known method using a metathesis polymerization catalyst.
The metathesis polymerization catalyst is not particularly limited and known ones are used. As a metathesis polymerization catalyst, a catalyst system comprising a metal halide, nitrate or acetylacetone compound selected from ruthenium, rhodium, palladium, osmium, iridium and platinum and a reducing agent; from titanium, vanadium, zirconium, tungsten and molybdenum A catalyst system comprising a selected metal halide or acetylacetone compound and a co-catalyst organoaluminum compound; a Schrock-type or Grubbs-type living ring-opening metathesis polymerization catalyst (JP-A-7-179575, J. Am. Chem. Soc., 1986, 108, p.733, J. Am.Chem.Soc., 1993, 115, p.9858, and J.Am.Chem.Soc., 1996, 118, p.100); Etc.
These metathesis polymerization catalysts can be used alone or in combination of two or more.

  The amount of the metathesis polymerization catalyst used may be appropriately selected depending on the polymerization conditions and the like, but is usually 0.000001 to 0.1 mol, preferably 0.00001 to 0.01 with respect to 1 mol of the cyclic olefin monomer. Is a mole.

When performing ring-opening polymerization of a cyclic olefin monomer, a linear α-olefin having 4 to 40 carbon atoms such as 1-butene, 1-hexene, 1-decene and the like can be used as a molecular weight regulator.
The addition amount of the linear α-olefin is usually 0.01 to 0.50 mol, preferably 0.03 to 0.30 mol, more preferably 0.05 to 0, relative to 1 mol of the cyclic olefin monomer. .15 moles.

  The ring-opening polymerization of the cyclic olefin monomer can be performed in an organic solvent. The organic solvent is not particularly limited as long as it is inert to the polymerization reaction. Specific examples thereof include the same solvents as those described above as the solvent contained in the liquid phase.

  Although superposition | polymerization temperature is not specifically limited, Usually, -50-250 degreeC, Preferably it is -30-200 degreeC, More preferably, it is -20-150 degreeC. The polymerization time is appropriately selected depending on the polymerization conditions, but is usually 30 minutes to 20 hours, preferably 1 to 10 hours.

The polymer (α) can be obtained by subjecting the polymer (β) obtained by the above method to a hydrogenation reaction.
The hydrogenation reaction of the polymer (β) can be carried out by bringing the polymer (β) into contact with hydrogen in the presence of a hydrogenation catalyst according to a conventional method.

The hydrogenation catalyst may be a homogeneous catalyst or a heterogeneous catalyst.
The homogeneous catalyst can be easily dispersed in the hydrogenation reaction solution, so that the amount of catalyst added can be suppressed. In addition, the polymer (α) and the polymer (β) are not easily decomposed or gelled because they have sufficient activity even without high temperature and pressure. For this reason, it is preferable to use a homogeneous catalyst from the viewpoint of cost and product quality.
On the other hand, since the heterogeneous catalyst exhibits particularly excellent activity under high temperature and high pressure, the polymer (β) can be hydrogenated in a short time.

  As homogeneous catalysts, Wilkinson complex [chlorotris (triphenylphosphine) rhodium (I)], dichlorobis (triphenylphosphine) palladium, chlorohydridocarbonyltris (triphenylphosphine) ruthenium, bis (tricyclohexylphosphine) benzilidineruthenium ( IV) Dichloride; transition metal compounds such as combinations of cobalt acetate / triethylaluminum, nickel acetylacetonate / triisobutylaluminum, titanocene dichloride / n-butyllithium, zirconocene dichloride / sec-butyllithium, tetrabutoxytitanate / dimethylmagnesium, etc. And a catalyst comprising a combination of an alkyl metal compound and the like.

  Examples of the heterogeneous catalyst include those in which a metal such as Ni, Pd, Pt, Ru, and Rh is supported on a carrier. In particular, when reducing the amount of impurities in the hydride obtained, it is preferable to use an adsorbent such as alumina or diatomaceous earth as the carrier.

  The hydrogenation reaction is usually performed in an organic solvent. The organic solvent is not particularly limited as long as it is inert to the hydrogenation reaction. Specific examples thereof include the same solvents as those described above as the solvent contained in the liquid phase. In general, the solvent used in the ring-opening polymerization reaction is also suitable as a solvent for the hydrogenation reaction. Therefore, after adding a hydrogenation catalyst to the ring-opening polymerization reaction solution, it can be used for the hydrogenation reaction.

  The hydrogenation rate varies depending on the type of hydrogenation catalyst and the reaction temperature. Therefore, when the polymer (β) has an aromatic ring, the residual ratio of the aromatic ring can be controlled by selecting a hydrogenation catalyst or adjusting the reaction temperature. For example, in order to leave an unsaturated bond in the aromatic ring more than a certain amount, control such as lowering the reaction temperature, lowering the hydrogen pressure, or shortening the reaction time may be performed.

In the polymer (α), usually, the degree of syndiotactic stereoregularity (racemo dyad ratio) tends to be higher in crystallinity.
The degree of stereoregularity of the polymer (α) is not particularly limited, but the ratio of the racemo dyad with respect to the repeating unit is preferably 60% or more, more preferably 70% or more, and 88% The above is particularly preferable.

The ratio of the racemo dyad can be determined by measuring with ¹³ C-NMR spectrum analysis. Specifically, an inverse-gated decoupling method is applied at 200 ° C. using a mixed solvent (volume ratio 2: 1) of 1,3,5-trichlorobenzene-d3 / 1,2-dichlorobenzene-d4 as a solvent. ¹³ C-NMR measurement was performed, and a peak of 127.5 ppm of 1,2-dichlorobenzene-d4 was used as a reference shift, and a signal of 43.35 ppm derived from meso dyad and a signal of 43.43 ppm derived from racemo dyad The ratio of racemo dyad can be determined from the intensity ratio.

In general, the stereoregularity of the polymer does not change before and after the hydrogenation reaction. Therefore, the polymer (α) having a high syndiotactic stereoregularity is obtained by, for example, subjecting a cyclic olefin monomer to ring-opening polymerization to obtain a polymer (β) having a high syndiotactic stereoregularity. It can be obtained by subjecting it to a hydrogenation reaction.
For example, the polymer (α) having high syndiotactic stereoregularity can be synthesized according to the methods described in WO2012 / 033076, JP2014-118475A, and the like.

[Method for reducing the amount of solid phase in a solid-liquid two-phase system]
The method for reducing the amount of solid phase of the present invention is a method for reducing the amount of solid phase in a solid-liquid two-phase system of the liquid phase and the solid phase, wherein the polymer (α) constituting the solid phase is reduced. In contact with hydrogen in the presence of a metal or metal compound.

  The solid-liquid two-phase system is not particularly limited as long as the solid phase and the liquid phase coexist. For example, the polymer (α) is placed on the system in a state where the particles of the polymer (α) are dispersed or deposited in the liquid phase to form a solid phase, or on the wall surface of the container in which the liquid phase exists. Examples include a system in a state of being adhered to form a solid phase.

  “Reducing the amount of solid phase in a solid-liquid two-phase system” means reducing the total volume of the solid phase or the total weight of the solid phase. The change can be visually confirmed when the suspension changes into a solution. If the solid phase remains in the system even after reducing the amount of solid phase, perform solid-liquid separation on the suspension before and after the treatment and measure the weight of each solid. Thus, the reduction amount can be obtained.

The reason why the amount of solid phase is reduced in the reduction method of the present invention is considered as follows. That is, the hardly-soluble crystalline cyclic olefin polymer hydride is converted into a substance having higher solubility in the solvent than the polymer (α) by contacting with hydrogen in the presence of a metal or a metal compound, It is considered that the amount of the solid phase can be reduced as a result by completely or partially dissolving in the solvent.
Here, the “substance having higher solubility in the solvent than the polymer (α)” has a solubility in the solvent at 40 ° C. of preferably 5 g / 100 g (solvent) or more, more preferably 10 g / 100 g (solvent). That's it.

  The reason why the polymer (α) is inferior in solubility in a general solvent is that, when the stereoregularity of the polymer chain is high, the polymer chains interact with each other rather than the polymer chains interact with the solvent molecules. It is considered that the effect of the present invention can be obtained by reducing the molecular weight or isomerization of the polymer (α) and weakening the interaction between the polymer chains because it is considered that the thermodynamic stability is higher. Conceivable.

  Examples of the material having a high solubility in the solvent in which the hardly soluble crystalline cyclic olefin polymer hydride has been converted include those in which the crystallinity of the crystalline cyclic olefin polymer hydride has decreased due to contact with hydrogen, Isomerization reaction products, decomposition products of crystalline cyclic olefin polymer hydrides (molecular chains are cut and the molecular weight is reduced), and the like.

  The metal or metal compound is not particularly limited as long as the polymer (α) can be converted into a substance having higher solubility in the solvent by contacting with hydrogen in the presence of this substance. Among them, those capable of catalyzing a low molecular weight reaction of the polymer (α) and those capable of catalyzing an isomerization reaction of the polymer (α) are preferable, and can catalyze an isomerization reaction of the polymer (α). Those are more preferred.

Examples of the metal include Co, Ni, Mo, Pd, W, and Pt.
Examples of the metal compound include oxides of the metal.
Among these, the metal or metal compound is preferably metal nickel or a nickel compound because the polymer (α) can be more efficiently converted to a substance having higher solubility in the solvent.
In the method of the present invention, the metal or metal compound can be used alone or in combination of two or more.

A metal or metal compound supported on a carrier may be used.
Examples of the carrier include silica, alumina, silica-alumina, titania, zirconia, zeolite, diatomaceous earth, and the like.

The amount of the metal or metal compound to be used is not particularly limited, but is usually 5 to 40 parts by weight, preferably 10 to 20 parts by weight with respect to 100 parts by weight of the polymer (α).
When the amount of metal or metal compound is too small, it may be difficult to sufficiently reduce the solid phase amount. On the other hand, even if the amount of the metal or metal compound is too large, there is a possibility that the effect corresponding to the amount cannot be obtained.

The conditions for bringing the polymer (α) into contact with hydrogen are not particularly limited.
The hydrogen pressure is usually 3.0 to 7.0 MPa, preferably 3.5 to 4.5 MPa.
The contact temperature is usually 200 to 250 ° C, preferably 210 to 230 ° C.
The contact time is usually 60 to 720 minutes, preferably 120 to 360 minutes.

By using the method of the present invention, the amount of solid phase in the solid-liquid two-phase system can be efficiently reduced.
By using the method for reducing the amount of solid phase in the solid-liquid two-phase system of the present invention, the suspension can be transferred efficiently or the reactor can be cleaned efficiently.
In particular, the present invention is preferably used in the case of washing a reactor to which a refractory crystalline cyclic olefin polymer hydride adheres as a scale, as described later, for use in a hydrogenation reaction of a cyclic olefin polymer. .

2) Reactor cleaning method The reactor cleaning method of the present invention is a reactor cleaning method in which a crystalline cyclic olefin polymer hydride adheres as a scale, and a solvent is put into the reactor. A solid-liquid two-phase system composed of a liquid phase containing the solvent and a solid phase made of a crystalline cyclic olefin polymer hydride that is hardly soluble in the solvent, and the amount of solid phase constituting the solid-liquid two-phase system is It is characterized by using the method for reducing the amount of solid phase in a solid-liquid two-phase system according to the present invention.

  First, a solvent is put in a reactor in which a crystalline cyclic olefin polymer hydride is attached as a scale (a solid phase made of a crystalline cyclic olefin polymer hydride that is hardly soluble in a general solvent). A solid-liquid two-phase system of a liquid phase containing a solid phase composed of a hydride of a crystalline cyclic olefin polymer hardly soluble in the solvent is formed.

The solvent used here (hereinafter sometimes referred to as “washing solvent”) is the same as that shown above as the solvent contained in the liquid phase in the invention of the method for reducing the amount of solid phase in a solid-liquid two-phase system. The same thing is mentioned.
Of these, the same solvent (same type) as the solvent used in the hydrogenation reaction of the cyclic olefin polymer is preferable. When the reactor cleaning method of the present invention is performed using a solvent different from the solvent for the hydrogenation reaction of the cyclic olefin polymer and the cleaning solvent cannot be completely removed, the next hydrogen is left in a state where a trace amount of the cleaning solvent remains. When the hydrogenation reaction is performed, it may adversely affect the hydrogenation reaction. On the other hand, when the same solvent as that used in the hydrogenation reaction of the cyclic olefin polymer is used, such a problem is avoided.
The amount of the cleaning solvent to be used is not particularly limited, but the amount of the cleaning solvent is such that a solid-liquid two-phase system similar to the solid-liquid two-phase system in the invention of the method for reducing the amount of solid phase in the solid-liquid two-phase system is formed. It is preferable to use it.
Moreover, it is preferable to fill the reactor with the cleaning solvent so that the scale attached to the reactor is immersed in the cleaning solvent.

  Next, the amount of solid phase constituting the solid-liquid two-phase system is reduced using the method for reducing the amount of solid phase in the solid-liquid two-phase system of the present invention.

  After reducing the amount of the solid phase constituting the solid-liquid two-phase system, the obtained solution or suspension may be discharged from the reactor. For example, it can be carried out by providing a discharge line for discharge in the reactor and discharging the solution therefrom or pumping the solution from the reactor.

According to the reactor cleaning method of the present invention, the reactor in which the crystalline cyclic olefin polymer hydride adheres as a scale inside the container can be efficiently cleaned.
Therefore, when producing a crystalline cyclic olefin polymer hydride industrially, the target crystalline cyclic olefin polymer hydride can be produced more efficiently.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited to these examples. In the following, “part” and “%” are based on weight unless otherwise specified, and pressure is gauge pressure.

Various physical properties were measured according to the following methods.
(1) Weight average molecular weight (Mw) and number average molecular weight (Mn)
The molecular weight (weight average molecular weight and number average molecular weight) of the cyclic olefin polymer is gel permeation chromatography (GPC) at 40 ° C. using tetrahydrofuran as a solvent [System: HLC-8320 (manufactured by Tosoh Corporation); Column: H type Column (manufactured by Tosoh Corporation)] and determined as a standard polystyrene equivalent value.

(2) Hydrogenation rate of crystalline cyclic olefin polymer hydride
¹ H-NMR was measured to determine the hydrogenation rate of the crystalline cyclic olefin polymer hydride.

(3) Melting point The melting point of the crystalline cyclic olefin polymer hydride was determined by using a differential scanning calorimeter (DSC) to heat the sample to 300 ° C. under a nitrogen atmosphere, and then rapidly quenching the sample with liquid nitrogen. The temperature was measured in minutes and measured.

(4) Solubility of crystalline olefin polymer hydride [g / 100 g (solvent)]
200 g of a solvent and 1 g of methylcyclohexane as an internal standard substance are added to and suspended in 10 g of a crystalline cyclic olefin polymer hydride which has been sufficiently washed and dried as a pretreatment, and heated and stirred at 40 ° C. Then, the soluble component in the solid content was extracted into the liquid phase. After allowing the suspension to stand, using the supernatant as a sample, gel permeation chromatography (GPC) at 40 ° C. [System: HLC-8320 (manufactured by Tosoh Corp.); column: H type column (manufactured by Tosoh Corp.) Solvent: cyclohexane].
In the chromatogram, the ratio of the peak area (A) of the crystalline cyclic olefin polymer hydride to the peak area (B) of the internal standard substance was calculated to determine the solubility.

[Production Example 1] (Production of dicyclopentadiene ring-opening polymer)
A catalyst solution was obtained by dissolving 0.3 part of n-hexane solution of 19% concentration of diethylaluminum ethoxide and 0.1 part of tetrachlorotungstenphenylimide (tetrahydrofuran) complex in 3 parts of toluene.
On the other hand, in a metal reactor (Sumitomo Heavy Industries, Ltd.) equipped with a stirrer and temperature control jacket, the inside of which was sufficiently dried and replaced with nitrogen, 350 parts of cyclohexane, 6.4 parts of 1-hexene, concentration 70% 145 parts of a cyclohexane solution of dicyclopentadiene (endo content rate of 99% or more) was added, and the whole volume was heated to 50 ° C. The catalyst solution was added thereto to initiate a ring-opening polymerization reaction.
After stirring for 270 minutes while maintaining the entire volume at 50 to 60 ° C., 1.5 parts of methanol was added to stop the ring-opening polymerization reaction. In addition, the effect which insolubilizes a catalyst part is also acquired by adding methanol to a polymerization reaction liquid.
The weight average molecular weight (Mw) of the dicyclopentadiene ring-opening polymer contained in the obtained polymerization reaction solution was 28,700, and the number average molecular weight (Mn) was 9570.

  To the obtained polymerization reaction liquid, 1 part of diatomaceous earth (manufactured by Showa Chemical Industry Co., Radiolite # 1500) was added as a filter aid. The suspension was subjected to filtration with a leaf filter (CFR2 manufactured by IHI), and the insolubilized catalyst was separated with diatomaceous earth to obtain a dicyclopentadiene ring-opened polymer solution.

[Production Example 2] (Production of hydride of dicyclopentadiene ring-opening polymer)
After the dicyclopentadiene ring-opened polymer solution obtained in Production Example 1 was transferred to a reactor equipped with a stirrer and a temperature control jacket (manufactured by Sumitomo Heavy Industries, Ltd.), the concentration of the dicyclopentadiene ring-opened polymer was 9 % Cyclohexane 600 parts and chlorohydridocarbonyltris (triphenylphosphine) ruthenium 0.1 part were added. Next, while stirring the whole volume at a rotational speed of 64 rpm, a hydrogenation reaction was performed at a hydrogen pressure of 4 MPa and a temperature of 180 ° C. for 6 hours to obtain a slurry containing dicyclopentadiene ring-opened polymer hydride particles.
A part of this slurry was collected and used as various analytical samples, and samples of Examples 2 to 5 and Comparative Examples 1 to 6.

When the obtained dicyclopentadiene ring-opening polymer hydride was analyzed, the hydrogenation rate was 99.5%.
The melting point of the dicyclopentadiene ring-opening polymer hydride was 266 ° C.
The solubility of the dicyclopentadiene ring-opened polymer hydride in cyclohexane was 0.1 g / 100 g or less of cyclohexane at 40 ° C. Further, the solubility of dicyclopentadiene ring-opened polymer hydride in decalin was 0.1 g / decalin 100 g or less, and the solubility in orthodichlorobenzene was 0.1 g / orthodichlorobenzene 100 g or less.

[Example 1]
After the slurry containing the dicyclopentadiene ring-opened polymer hydride particles obtained in Production Example 2 was withdrawn from the drain line of the reactor, cyclohexane having the same weight as the withdrawn slurry was placed in the reactor.
When the slurry was extracted, it was visually confirmed that the scale was attached to the wall surface.
Next, 0.5% of a diatomaceous earth-supported nickel catalyst (Clariant Catalysts, T-8400RL) was added to cyclohexane, and the whole volume was stirred at a hydrogen pressure of 4 MPa and a temperature of 180 ° C. for 6 hours.
After the contents in the reactor were drained, the inside of the reactor was visually confirmed, and no polymer scale was attached to the wall surface.
Further, the concentration of the polymer contained in the drained solution was 2%.

[Example 2]
In order to examine the conditions for the above washing operation (Example 1), the following model experiment was conducted.
Part of the slurry of the dicyclopentadiene ring-opening polymer hydride obtained in Production Example 2 was subjected to solid-liquid separation to isolate the dicyclopentadiene ring-opening polymer hydride.
100 parts of this dicyclopentadiene ring-opened polymer hydride and 4000 parts of cyclohexane were put into a reactor to form a solid-liquid two-phase system.
Next, 20 parts of the diatomaceous earth-supported nickel catalyst was added to the solid-liquid two-phase system, and the reaction was performed at a hydrogen pressure of 4 MPa and a temperature of 220 ° C. for 240 minutes.

[Examples 3-5, Comparative Examples 1-6]
A reaction between a hydrogenated dicyclopentadiene ring-opening polymer and hydrogen was carried out in the same manner as in Example 2 except that the conditions were changed to those described in Table 1.

(Evaluation of fluidity of reaction liquid)
The fluidity of the reaction solutions obtained in Examples 2 to 5 or Comparative Examples 1 to 6 was evaluated according to the following criteria. The results are shown in Table 1.
○: It flows without problems.
Δ: Transfer is possible by stirring, but solid content is obstructive and difficult to flow.
X: It does not flow.

(Quantification of undissolved residue)
The solid contents of the reaction liquids obtained in Examples 2 to 5 or Comparative Examples 1 to 6 were collected by filtration and dried, and the amount of the polymer contained in the solid contents was determined. Based on the amount of dicyclopentadiene ring-opening polymer hydride used, the ratio (%) of the polymer that was a residue was calculated. 0% is a state in which the dicyclopentadiene ring-opening polymer hydride is completely dissolved, and 100% is a state in which the dicyclopentadiene ring-opening polymer hydride remains completely.
The results are shown in Table 1.

The following can be seen from Table 1.
In Examples 2-5, the obtained reaction liquid has sufficient fluidity | liquidity. Therefore, by using these conditions, the reactor can be cleaned efficiently.
On the other hand, in Comparative Examples 1 to 6, the dicyclopentadiene ring-opened polymer hydride is almost undissolved and the reaction solution is inferior in fluidity.

Claims (8)

A method for reducing the amount of solid phase in a solid-liquid two-phase system comprising a liquid phase containing a solvent and a solid phase comprising a crystalline cyclic olefin polymer hydride that is hardly soluble in the solvent,
A method for reducing the amount of solid phase in a solid-liquid two-phase system, wherein the hydride of a crystalline cyclic olefin polymer constituting the solid phase is brought into contact with hydrogen in the presence of a metal or a metal compound.   The method for reducing the amount of solid phase according to claim 1, wherein the solvent is a cycloalkane solvent.   The method for reducing the solid phase amount according to claim 1 or 2, wherein the solubility of the crystalline cyclic olefin polymer hydride in the solvent at 40 ° C is 1 g / 100 g (solvent) or less.   The method for reducing the solid phase amount according to any one of claims 1 to 3, wherein the metal or metal compound catalyzes an isomerization reaction of a crystalline cyclic olefin polymer hydride.   The method for reducing the solid phase amount according to any one of claims 1 to 4, wherein the metal or metal compound is nickel metal or a nickel compound.   The hydrogen pressure when the crystalline cyclic olefin polymer hydride is brought into contact with hydrogen is 3.0 to 7.0 MPa, and the reaction temperature is 200 to 250 ° C. Method for reducing the amount of solid phase. A cleaning method for a reactor in which a crystalline cyclic olefin polymer hydride is attached as a scale inside,
A solvent is put into the reactor, and a solid-liquid two-phase system comprising a liquid phase containing the solvent and a solid phase made of a crystalline cyclic olefin polymer hydride that is hardly soluble in the solvent is used. A method for washing a reactor, wherein the amount of the solid phase constituting the catalyst is reduced using the method according to claim 1. The scale attached to the reactor is generated by a hydrogenation reaction of a cyclic olefin polymer,
The method for washing a reactor according to claim 7, wherein the same solvent as that used in the hydrogenation reaction of the cyclic olefin polymer is used as the solvent.