TW201643151A - Manufacturing apparatus and manufacturing method of cyclic carbonate - Google Patents

Abstract

The present invention provides a continuous manufacturing apparatus and manufacturing method of cyclic carbonate. Even when a fixed catalyst is used as a catalyst and its manufacture is done on an industrial scale, a large-scale reactor or excessively large auxiliary equipment is not required, which allows the scale to be easily expanded without destroying the expected catalyst efficiency and life so as to produce cyclic carbonate with excellent economical and industrial productivity. The cyclic carbonate manufacturing apparatus of the present invention is characterized by comprising a thermal insulation type reactor for filling heterogeneous catalyst for the reaction of epoxide and carbon dioxide; a circulation path for returning at least a portion of the liquiform mixed fluid discharged from the outlet of the reactor; a carbon dioxide supply mechanism for continuously supplying carbon dioxide in a liquid state or supercritical state to the circulation path; and an epoxide supply mechanism for continuously supplying liquiform or liquid-like epoxide to the circulation path. The said circulation path includes a heat exchange mechanism for removing heat from the circulating fluid by indirect heat exchange; a mixing mechanism for mixing the carbon dioxide supplied by the carbon dioxide supply mechanism with the circulating fluid in the path; a gas-liquid separation mechanism for gas-liquid separation treatment by decompressing carbon dioxide-containing circulating fluid obtained by the mixing mechanism; a boosting mechanism to boost the pressure of the gas-liquid treated circulating fluid to a specific pressure; and a mixing mechanism for mixing the epoxide supplied from the epoxide supply mechanism with the circulating fluid in the path.

Description

Cyclic carbonate manufacturing device and manufacturing method

The present invention relates to a device and a method for producing a cyclic carbonate. More specifically, it relates to a device and a method for producing a cyclic carbonate which reacts an epoxide with carbon dioxide in the presence of a heterogeneous catalyst.

The cyclic carbonate is used as an organic solvent, a synthetic fiber processing agent, a pharmaceutical raw material, a cosmetic additive, and more recently, it is used as an electrolyte solvent for a lithium battery, and is also used as an alkyl diol or a dialkyl carbonate. The synthesis of esters and the like is one of important compounds which are used in a wide range of applications.

Previously, the cyclic carbonate was synthesized by reacting an epoxide with carbon dioxide under appropriate pressurization conditions in the presence of a homogeneous catalyst. As such a homogeneous catalyst, a phosphonium salt such as an alkali metal or a phosphonium salt such as a quaternary ammonium salt (Patent Document 1) has been known for industrial use.

However, in the case of using a homogeneous catalyst, in general, separation of the reaction mixture from the catalyst by distillation or the like is required, and not only the manufacturing steps are complicated, but also the decomposition of the catalyst in the separation step or Problems such as the formation of by-products.

Therefore, in order to simplify the catalyst separation process, a heterogeneous catalyst obtained by fixing a quaternary sulfhydryl group having a halide ion as a counter ion to a carrier such as silicone rubber has been proposed as a propyl carbonate carbonate using the fixed catalyst. In the production method, a method in which mixed propylene oxide and supercritical carbon dioxide are supplied to a reaction tube filled with the above fixed catalyst to continuously produce propylene carbonate is disclosed (Patent Document 2).

However, since the fixed catalyst is less active than the homogeneous catalyst, a large amount of catalyst is required, and in particular, when the cyclic carbonate is to be produced on an industrial scale, there is a problem that the reactor is enlarged.

Further, since the amount of the liquid passing through the reaction liquid is smaller than the amount of the catalyst, there are problems in that (1) a bias flow of the reaction liquid occurs in the reactor, and (2) contact between the catalyst and the reaction liquid, that is, a catalyst. The wetting is insufficient and the function of the catalyst cannot be fully utilized. Further, the bias current in the system becomes a cause of hot spots (local overheating of the catalyst), and the catalyst deterioration is remarkably accelerated.

On the other hand, the case where the carbon dioxide in the reactor is vaporized is also the same as described above, and the bias flow occurs in the system, or the wetting of the catalyst is insufficient, which is a factor for reducing the catalyst efficiency and the catalyst life.

Further, even in the case where carbon dioxide is not vaporized, if the mixing of carbon dioxide is insufficient, the reaction liquid is not necessarily a uniform phase. For example, in Patent Document 2, propylene oxide and supercritical carbon dioxide are mixed, but as described in Non-Patent Document 1, the propylene carbonate as a product is phase-separated from supercritical carbon dioxide. Therefore, in order to sufficiently dissolve carbon dioxide in the reaction liquid and to suppress phase separation in the reactor, it is necessary to completely mix, and a large-scale attached equipment such as a stirring tank is required.

Further, if the temperature of the fixed catalyst is increased, the catalyst component is desorbed and the activity is remarkably lowered. On the other hand, the reaction of the epoxide with carbon dioxide is accompanied by an exothermic reaction of a large reaction heat (for example, ethylene oxide and The reaction heat of the reaction of carbon dioxide is about 100 kJ/mol), so there is a problem of removing the heat of reaction in the synthesis of the cyclic carbonate when a fixed catalyst is used.

As the method for removing the heat of reaction described above, a method of using a heat exchange type reactor such as a jacketed reactor or a multitubular reactor is generally used.

However, the heat removal by the jacketed reactor that circulates the heat medium in the jacket exists. If the reactor is increased, the heat removal area is reduced compared with the amount of the catalyst, and only the heat removal surface can be used. The basic problem of removing heat from the nearby fixed catalyst.

On the other hand, in a multi-tubular reactor in which a plurality of reaction tubes are incorporated in a reactor casing, a reaction is carried out by filling a catalyst into a reaction tube, and on the other hand, a heat medium is circulated and removed in a reaction tube casing to be removed. The reaction heat is increased, so that the heat removal area can be increased. However, when a catalyst immobilized on a carrier such as silicone is used, since the flow rate is extremely small compared to the amount of the catalyst, it is necessary to make the reaction tube extremely thin and extremely long in order to obtain sufficient heat removal efficiency, and the device is complicated and large. Chemical. Also, maintenance has become complicated. Further, there is also a problem that it is difficult to uniformly fill the catalyst in a plurality of reaction tubes.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Publication No. 63-17072

[Patent Document 2] International Publication No. 2005/084801

[Non-patent literature]

[Non-Patent Document 1] Report on Research and Development Results of Environmental Load Reduction Technology Using Supercritical Fluids, March 2002, Industrial Technology Research Institute

Thus, if a cyclic carbonate is to be produced on an industrial scale using a fixed catalyst, a large-scale apparatus such as a large reactor, a cooling device, a mixing device, and the like is required. Moreover, in the case of a process requiring such a large reactor or an attached device, there is also a problem that it is difficult to scale up.

Accordingly, an object of the present invention is to provide a continuous production apparatus and a production method of a cyclic carbonate which do not require a large reactor or an excessively large equipment even when a fixed catalyst is used as a catalyst and is manufactured on an industrial scale. It is easy to expand the scale, and it is possible to produce a cyclic carbonate without impairing the expected catalyst efficiency and catalyst life, and it is economical and industrially excellent.

In order to solve the above problems, the present invention provides [1] a device for producing a cyclic carbonate, comprising: an adiabatic reactor for supplying a heterogeneous catalyst for reacting an epoxide with carbon dioxide; a circulation path; And returning at least a portion of the liquid mixed fluid flowing out from the outlet of the reactor to the reactor; a carbon dioxide supply mechanism continuously supplying carbon dioxide in a liquid or supercritical state to the circulation path; and an epoxide supply mechanism And continuously supplying a liquid or solution epoxide to the circulation path; and the circulation path includes: a heat exchange mechanism that circulates the fluid (liquid mixed fluid flowing into the circulation path) by indirect heat exchange a heat removal mechanism that mixes carbon dioxide supplied by the carbon dioxide supply mechanism with the circulating fluid in a path; and a gas-liquid separation mechanism that decompresses a circulating fluid containing carbon dioxide obtained by the mixing mechanism, Performing a gas-liquid separation process; a pressure increasing mechanism that boosts the circulating fluid after the gas-liquid separation process to Prescribed pressure; and a mixing mechanism that is supplied by the above-described epoxide epoxide is mixed with the feed means in the circulating fluid path.

The present invention provides the apparatus for producing a cyclic carbonate according to the above [1], wherein the reactor is configured as a fixed bed multistage reaction in which two or more adiabatic reactors are connected in series. The circulation path is provided such that at least a portion of the liquid mixed fluid flowing out from the outlet of the last stage reactor is returned to the first stage reactor.

In the present invention, the amount of the catalyst relative to the amount of the cyclic carbonate produced is not substantially affected by the number of reactors, and is substantially fixed. Therefore, the production apparatus of the above [2] is easy to add a reactor to enhance the productivity.

Further, in order to solve the above problems, the present invention provides a method for producing a cyclic carbonate, characterized in that a mixed fluid containing a raw material of an epoxide and carbon dioxide is continuously supplied to an adiabatic reactor filled with a heterogeneous catalyst. And introducing at least a portion of the liquid mixed fluid flowing out from the outlet of the reactor to a circulation path to return to the reactor; and comprising: a heat exchange step of inverting the circulating fluid by indirect heat exchange a liquid mixed fluid of a circulation path), a carbon dioxide supply step of continuously supplying carbon dioxide in a liquid or supercritical state to the circulation path, and a mixing step of carbon dioxide supplied by the carbon dioxide supply step and the cycle The fluid is mixed in the path; a gas-liquid separation step, which decompresses the circulating fluid containing carbon dioxide obtained by the mixing step, and performs gas-liquid separation treatment on the remaining carbon dioxide of the gasification; and a pressure increasing step, which separates the gas and liquid The subsequent circulating fluid is boosted to a specific pressure; an epoxide supply step, which is to the above cycle Continuously feeding a liquid or solution form inner diameter of the epoxide; and a mixing step of epoxide epoxide by the above-described supplying step of mixing with the supplied fluid in the circulation path.

Furthermore, the present invention provides the method for producing a cyclic carbonate according to the above [3], wherein the reactor is configured as a fixed bed multistage reaction in which two or more adiabatic reactors are connected in series. The circulation path is such that at least a portion of the liquid mixed fluid flowing out of the outlet of the last stage reactor is returned to the first stage reactor.

Since the amount of the catalyst relative to the amount of the cyclic carbonate produced in the present invention is substantially constant irrespective of the number of reactors, the production method of the above [4] can easily enhance the productivity by adding a reactor.

According to the present invention, it is possible to provide a cyclic carbonate producing apparatus and a manufacturing method which can be easily scaled up by adding a reactor without requiring a large reactor or an excessively attached equipment, and can suppress the drift or phase separation of the reaction liquid. The reaction heat is efficiently removed, and the cyclic carbonate is produced without impairing the expected catalyst efficiency and catalyst life, and is economical and industrially excellent.

1‧‧‧reactor

1a‧‧‧reactor outlet

1b‧‧‧reactor inlet

2‧‧‧Circular path

3‧‧‧Drainage path

4‧‧‧Hot Exchange Agency

5‧‧‧Hot Exchange Agency

6‧‧‧CO2 supply agency

7‧‧‧Additive supply mechanism

8‧‧‧epoxide supply mechanism

9‧‧‧Mixed institutions

10‧‧‧Mixed institutions

11‧‧‧ gas-liquid separation mechanism

12‧‧‧Booster

13‧‧‧Pressure control agency

14‧‧‧ Pressure Control Agency

15‧‧‧Control valve

16‧‧‧Control valve

20‧‧‧Mixed institutions

21‧‧‧Reactor

21a‧‧‧reactor outlet

21b‧‧‧reactor inlet

22‧‧‧Flow between reactors

24‧‧‧Hot Exchange Agency

26‧‧‧Control valve

30‧‧‧Mixed institutions

31‧‧‧Reactor

31a‧‧‧Reactor outlet

31b‧‧‧reactor inlet

32‧‧‧Flow between reactors

34‧‧‧Hot Exchange Agency

36‧‧‧Control valve

Fig. 1 is a view schematically showing an example of the first embodiment of the apparatus for producing a cyclic carbonate of the present invention.

Fig. 2 is a view schematically showing an example of a second embodiment of the apparatus for producing a cyclic carbonate of the present invention.

Fig. 3 is a graph showing the results of thermogravimetric measurement of a catalyst.

Figure 4 is a graph showing the effect of reaction pressure on the yield of ethyl carbonate.

Hereinafter, the invention will be described with reference to the accompanying drawings, as needed. In the description of the drawings, the same components are denoted by the same reference numerals, and the repeated description is omitted.

First, the raw material epoxide, the heterogeneous catalyst used in the present invention, and the cyclic carbonate obtained in the present invention will be described.

(epoxide)

The epoxide used in the present invention is not particularly limited as long as it is a compound having at least one epoxy ring (a three-membered ring containing two carbon atoms and one oxygen atom) in the structural formula, and for example, Ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, vinyl oxirane, trifluoromethyl oxirane, cyclohexene oxide, styrene oxide, monooxygen Ding Diene, butadiene oxide, 2-methyl-3-phenylcyclobutene, decene oxide, tetracyanoethylene oxide, and the like.

Among such epoxides, those represented by the following formula (1) are preferred, and ethylene oxide and propylene oxide are more preferred.

[In the formula (1), R ¹ and R ² each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a haloalkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, and a carbon number of 2 to 2; 6 haloalkenyl group, aryl group having 6 to 12 carbon atoms or cyano group, and R ³ and R ⁴ each independently represent a hydrogen atom, a cyano group or an aryl group having 6 to 12 carbon atoms; wherein R ³ and R ⁴ are Either of these may form a cycloalkyl group together with any of R ¹ and R ² ]

The alkyl group or haloalkyl group represented by the above R ¹ and R ² preferably has 1 to 4 carbon atoms. The alkyl group may, for example, be a methyl group, an ethyl group, a propyl group or a butyl group, preferably a methyl group or an ethyl group, more preferably a methyl group.

In addition, the number of carbon atoms of the alkenyl group or the haloalkenyl group represented by R ¹ and R ² is preferably 2 to 4, and specific examples thereof include a vinyl group and the like.

Further, examples of the halogen atom in the haloalkyl group and the haloalkenyl group include chlorine, bromine, and iodine.

Further, the aryl group represented by the above R ¹ , R ² , R ³ and R ⁴ is preferably a phenyl group.

Further, in the above R ¹ and R ² , a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a haloalkyl group having 1 to 6 carbon atoms is preferable.

Further, R ³ and R ^{4 are} preferably a hydrogen atom.

(heterogeneous catalyst)

The heterogeneous catalyst used in the present invention is preferably a fixed catalyst which is active when a cyclic carbonate is synthesized from an epoxide and carbon dioxide, and more preferably a solid catalyst in which an ionic organic compound is immobilized on a carrier.

Examples of such an ionic organic compound include a quaternary organic phosphonium salt selected from the group consisting of a quaternary organic ammonium salt having a halide anion as a counter ion and a quaternary organic phosphonium salt having a halide anion as a counter ion. Examples of the halide anion include a fluoride anion, a chloride anion, a bromine anion, and an iodine anion.

Specific preferred examples of the quaternary organic phosphonium salt include tetraalkylammonium salts such as tetraalkylammonium chloride and tetraalkylammonium bromide, and tetraalkylammonium chloride and tetraalkylphosphonium bromide. The base salt is preferably a tetraalkyl phosphonium salt.

Further, the carbon number of the alkyl group in the tetraalkylammonium salt or the tetraalkylphosphonium salt is preferably from 1 to 8, more preferably from 1 to 6, still more preferably from 2 to 4. For example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a cyclohexyl group, etc. are mentioned.

Further, examples of the carrier include an inorganic oxide carrier and an organic polymer carrier. Further, the shape thereof is preferably a particle shape, and it is preferably a porous one. Preferred examples of the inorganic oxide carrier include silicone (gelled cerium oxide), mesoporous cerium oxide, ceramics, zeolite, and porous glass. Among them, silicone or mesoporous cerium oxide is preferred. Further, examples of the organic polymer carrier include polystyrene, polystyrene copolymer, poly(meth)acrylate, poly(meth)acrylamide, polyamidimide, polybenzimidazole, and polyphenylene. and An azole, a polybenzothiazole, a polyethylene glycol, a polypropylene glycol, or a copolymer, a polymer blend or the like containing the polymer as a main component.

(cyclic carbonate)

Further, the cyclic carbonate obtained by the present invention has a structure in which an epoxy ring of the above epoxide is converted into a carbonate ring (a 5-membered ring having an O-CO-O bond), and for example, a carbonic acid Ester, propyl carbonate, butyl carbonate, isobutyl carbonate, trifluoromethyl carbonate Ethyl ethyl ester, ethyl vinyl carbonate, ethyl hexyl carbonate, styrene carbonate, butadiene carbonate, butadiene carbonate, chloromethyl carbonate, decyl carbonate, tetracyanocarbonate Ethyl ester and so on. A preferred cyclic carbonate is represented by the following formula (2).

[In the formula (2), R ¹ to R ^{4 are} synonymous with the above]

[(1) Manufacturing device of cyclic carbonate]

<First embodiment>

A manufacturing apparatus (first manufacturing apparatus) for a cyclic carbonate according to the first embodiment of the present invention will be described.

Fig. 1 is a view schematically showing an example of a manufacturing apparatus of a cyclic carbonate according to a first embodiment of the present invention.

As shown in Fig. 1, the manufacturing apparatus of the present embodiment includes an adiabatic reactor 1 for charging a heterogeneous catalyst for reacting epoxide with carbon dioxide, and a circulation path 2 for discharging from the reactor outlet 1a. One portion of the liquid mixed fluid is returned to the reactor 1; a discharge path 3 for discharging the remainder of the liquid mixed fluid is sent to the next step as needed. The liquid mixed fluid from the reactor outlet 1a mainly contains the cyclic carbonate formed in the reactor 1 and the unreacted carbon dioxide, and also contains unreacted epoxide depending on the reaction conditions.

The reactor 1 may be an adiabatic reactor configured to be filled with a heterogeneous catalyst for reacting an epoxide with carbon dioxide, and is preferably a tubular reactor. Structure The material of the reactor 1 is not particularly limited, and is preferably SUS (Steel Use Stainless) in terms of excellent corrosion resistance. Further, by using an inexpensive adiabatic reactor as the reactor 1, the equipment cost can be greatly reduced.

Further, when the reactor 1 is filled with a heterogeneous catalyst, glass beads or the like may be filled before and after the catalyst.

Further, a reactor inlet 1b is provided in the reactor 1. The reactor inlet 1b is configured such that the circulating fluid flows into the reactor 1 from the circulation path 2, and the circulating fluid obtained by supplying carbon dioxide and epoxide in the circulation path 2 is mixed as a raw material mixing fluid from the reactor inlet 1b. It is supplied to the reactor 1.

Further, the manufacturing apparatus of the present embodiment includes a carbon dioxide supply mechanism 6 that continuously supplies the liquid or supercritical carbon dioxide into the circulation path 2, and the epoxide supply mechanism 8 that continuously supplies the liquid to the circulation path 2 or Solution-like epoxide.

The carbon dioxide supply means 6 continuously supplies the carbon dioxide as a reaction raw material to the circulating fluid in a liquid or supercritical state, and continuously supplies the circulating fluid as a reaction material in a liquid or solution state by the epoxide supply mechanism 8. Epoxide. Further, with such a configuration, the supply amount of carbon dioxide and epoxide is controlled.

Examples of the carbon dioxide supply mechanism 6 and the epoxide supply mechanism 8 include a pump. By using a pump as such a mechanism, the supply amount of carbon dioxide or epoxide can be easily controlled. Moreover, the equipment cost can be greatly reduced.

Further, in the case where the epoxide is dissolved in a solvent and supplied as a solution in the epoxide supply mechanism 8, it is preferred to use a cyclic carbonate synthesized from the epoxide as a solvent. Specifically, in the case where ethylene oxide is dissolved in a solvent and supplied as a solution, the solvent is preferably ethyl carbonate.

Further, the manufacturing apparatus of the present embodiment may further include an additive supply mechanism 7 that supplies an additive or the like other than the reaction raw material into the circulation path 2. The additive supply means 7 supplies the additive to the circulation path 2 while controlling the supply amount.

The additive may be supplied continuously or discontinuously. Further, the additive may be supplied as a pure substance or may be dissolved in a solvent to be supplied as a solution. When it is dissolved in a solvent, the solvent is preferably a cyclic carbonate.

As the additive supply mechanism 7, a pump is mentioned.

Further, examples of the additive include halogenated alcohols such as bromoethanol and bromopropanol. The halogenated alcohol suppresses the desorption of the catalyst component and functions as a catalyst deterioration inhibitor.

Moreover, the manufacturing apparatus of this embodiment is equipped with the circulation path 2. In the circulation path 2, the heat exchange mechanism 4, the first mixing mechanism 9, the gas-liquid separation mechanism 11, the pressure increasing mechanism 12, and the second mixing mechanism 10 follow the heat exchange mechanism 4 from the reactor outlet 1a to the reactor inlet 1b. The first mixing mechanism 9, the gas-liquid separating mechanism 11, the pressure increasing mechanism 12, and the second mixing mechanism 10 are provided in this order.

By the circulation path 2, one of the liquid mixed fluids flowing out from the reactor outlet 1a is partially circulated to the reactor 1, and as a result, the amount of liquid passing through the reactor 1 becomes large, and it is easy to suppress the temperature rise in the reactor 1 at an appropriate level. Also in the range, the biasing of the reaction liquid or the insufficient wetting of the catalyst in the reactor 1 can be eliminated, so that the catalyst efficiency or the decrease in the catalyst life can be suppressed. Further, since the residence time can be prolonged, the amount of the catalyst can be reduced, and the size of the reactor 1 can be reduced.

The circulation path 2 is configured as any suitable piping. The material constituting the pipe is not particularly limited, but is preferably SUS in terms of excellent corrosion resistance.

Further, the circulation path 2 is provided with a heat exchange mechanism 4 that removes heat from the circulating fluid by indirect heat exchange.

Since the heat exchange mechanism 4 is provided by the circulation path 2, the heat of reaction can be easily removed, so that the temperature in the reactor 1 can be easily controlled to a desired range (substantially the reaction temperature). Since the heat of reaction is not sufficiently removed when the heat exchange mechanism 4 is not provided, the temperature in the reactor 1 rises and the life of the catalyst extremely shortens.

As the heat exchange mechanism 4, any heat exchanger can be used as long as the temperature of the circulating fluid passing through the mechanism can be lowered and the heat of reaction can be removed. Specific examples thereof include a multi-tube cylindrical heat exchanger, a double-tube heat exchanger, a plate heat exchanger, an air cooler, a rinse cooler, a coil heat exchanger, a spiral heat exchanger, and the like, and a double pipe. Heat exchangers, air coolers, and rinsing coolers are particularly suitable and preferred because of the relatively small flow of circulating fluid and high pressure operation. Further, the total heat transfer coefficient of the heat exchangers is preferably about 200 kcal/(m ² hrK) or more.

Further, it is preferable that the reactor outlet 1a and the heat exchange mechanism 4 are constituted only by the circulation path 2. With this configuration, the circulating fluid flowing out of the reactor outlet 1a can be quickly removed.

Further, in the circulation path 2, the carbon dioxide inflow portion into which the carbon dioxide supplied from the carbon dioxide supply mechanism 6 flows can be located in any one of the circulation paths, and is not particularly limited. However, since the thermal conductivity of carbon dioxide is low, the temperature is higher. Since the solubility of the latter is increased, it is preferable to supply and rapidly mix the circulating fluid after the heat removal. Therefore, it is preferably provided between the heat exchange mechanism 4 and the mixing mechanism 9.

Further, the circulation path 2 includes a mixing mechanism 9 (first mixing mechanism) that supplies the carbon dioxide supplied by the carbon dioxide supply mechanism 6 and the circulating fluid that has flowed into the circulation path 2 and is removed by the heat exchange mechanism 4 in the path. mixing.

The supplied carbon dioxide is uniformly mixed with other components by the mixing mechanism 9.

As the mixing mechanism 9, it is preferable to use an in-line mixer such as a static mixer because the apparatus is simple. By providing the in-line mixer by the circulation path 2, carbon dioxide can be efficiently mixed with other components in the flow path to obtain a uniform circulating fluid.

Further, as the circulation path 2, it is preferable that a pressure control mechanism 13 that controls the opening degree of the circulation path 2 is provided between the mixing mechanism 9 and the gas-liquid separation mechanism 11.

As the pressure control mechanism 13, a back pressure valve can be cited.

Further, the circulation path 2 includes a gas-liquid separation mechanism 11 that decompresses the circulating fluid containing carbon dioxide obtained by the mixing mechanism 9 to perform a gas-liquid separation process.

The remaining carbon dioxide gasified by the gas-liquid separation mechanism 11 is separated, and as a result, By suppressing the bias flow caused by the vaporization of the circulating fluid, the wetting of the heterogeneous catalyst in the reactor 1 can be eliminated, so that the catalyst can be efficiently utilized.

The gas-liquid separation mechanism 11 includes a gas-liquid separation tank that separates the supplied gas-liquid two-phase flow into a gas and a liquid, and can store the liquid. By using the gas-liquid separation tank, when the apparatus starts operating, the circulating fluid can be introduced into the gas-liquid separation tank and circulated to establish a circulation between the reactor 1 and the circulation path 2. Moreover, the circulating fluid can also be stored after the end of the operation.

Further, in the gas-liquid separating means 11, a gas discharge path for discharging the separated gas is provided above the portion to which the circulation path 2 is connected. Further, a pressure control mechanism 14 that controls the internal pressure of the gas-liquid separation mechanism 11 is provided in the gas discharge path.

As the pressure control mechanism 14, a back pressure valve can be cited.

By adjusting the pressure control mechanisms 13 and 14, a specific pressure difference can be imparted between the gas-liquid separation mechanism 11 and the mixing mechanism 9, and the remaining carbon dioxide can be vaporized and separated.

Further, the circulation path 2 includes a pressure increasing mechanism 12 that boosts the circulating fluid that has undergone the gas-liquid separation process by the gas-liquid separation mechanism 11 to a specific pressure.

The pressure-regulating mechanism 12 can control the circulating flow rate to be appropriate to raise it to a specific pressure (substantially the reaction pressure). Thereby, the circulating fluid is substantially in a state of not containing a gas phase, and gasification of carbon dioxide in the reactor 1 can be suppressed.

Examples of the pressure increasing mechanism 12 include a circulation pump and the like.

Further, in the circulation path 2, the epoxide inflow portion into which the epoxide supplied from the epoxide supply mechanism 8 flows is preferably provided in order to prevent the epoxide from being contained in the carbon dioxide vaporized by the gas-liquid separation treatment. Downstream of the gas-liquid separation mechanism 11, in order to suppress the side reaction, it is more preferably provided at a position close to the reactor inlet. Therefore, it is particularly preferably provided between the pressure increasing mechanism 12 and the mixing mechanism 10.

Further, as the circulation path 2, it is preferable to provide the heat exchange mechanism 5.

The temperature at the reactor inlet 1b can be adjusted by the cyclic ratio of the cyclic carbonate/epoxide of the reactor inlet 1b, but the passage through the reactor inlet 1b by the heat exchange mechanism 5. The premixing of the mixed fluid allows for easier adjustment of the temperature of the reactor inlet 1b. Further, the heat exchange mechanism 5 can be used in the case of preheating the system before the start of the reaction (before the introduction of the epoxide).

The heat exchange mechanism 5 is only required to be temperature-adjustable by indirect heat exchange. However, since it is operated at a high pressure, it is preferably a double-tube heat exchanger having a simple structure and a corresponding heat exchange efficiency.

Further, the heat exchange mechanism 5 may be located at any one of the circulation paths, and is not particularly limited. However, in order to suppress vaporization of carbon dioxide caused by heating, it is preferably disposed downstream of the gas-liquid separation tank 11.

Further, in the circulation path 2, the additive inflow portion into which the additive or the like supplied by the additive supply mechanism 7 flows can be located in any one of the circulation paths, and is not particularly limited. Since the supply amount of the additive is usually small, it is supplied upstream from the mixing mechanism 10, and it is not necessary to separately prepare the mixing mechanism.

Further, the circulation path 2 includes a mixing mechanism 10 (second mixing mechanism) that circulates the epoxide supplied from the epoxide supply mechanism 8 and the pressure that flows into the circulation path 2 and is boosted by the pressure increasing mechanism 12. The fluid is mixed in the path.

The supplied epoxide is uniformly mixed with other components by the mixing mechanism 10.

As the mixing mechanism 10, it is preferable to use an in-line mixer such as a static mixer because the apparatus is simple. By providing the in-line mixer by the circulation path 2, the epoxide can be efficiently mixed with other components in the flow path, and a uniform circulating fluid can be obtained.

The circulating fluid uniformly mixed by the mixing mechanism 10 is supplied as a raw material mixed fluid from the reactor inlet 1b to the adiabatic reactor 1 filled with the catalyst, and as a result, carbon dioxide reacts with the epoxide in the reactor 1. A cyclic carbonate is formed.

The supply amount (circulation speed) of the epoxide introduced into the reactor 1 is preferably 0.001 to 10 kg/hr, more preferably 0.01 to 1.0 kg/hr, and still more preferably 0.05 to 1 kg of the catalyst. 0.5 kg / hr.

The carbon dioxide content of the raw material mixed fluid introduced into the reactor 1 is preferably from 1 to 20, more preferably from 1.1 to 10, particularly preferably from 1.2 to 5, based on the carbon dioxide/epoxide ratio (mole ratio).

Further, the amount of the catalyst charged in the reactor 1 may be any amount within the range satisfying the above-described flow rate, depending on the amount of the cyclic carbonate to be produced.

Further, the cyclic carbonate/epoxide ratio (mass ratio) to be circulated to the reactor 1 is preferably 1 or more, more preferably 10 or more, still more preferably 12.5 or more, particularly preferably 15 or more, and further preferably It is 100 or less, more preferably 80 or less, further preferably 60 or less, further preferably 50 or less, further preferably 40 or less, and particularly preferably 30 or less. By adjusting the ratio, the temperature of the reactor inlet 1b can be adjusted.

Further, since the raw material mixed fluid does not substantially contain the gas phase, it can flow from the upper portion of the reactor 1 to the lower portion (downflow mode), or from the lower portion of the reactor 1 to the upper portion (upward flow mode), but if it is an upward flow In other words, even in the case where bubbles are generated, the bubbles are likely to disappear, which is preferable.

The liquid mixed fluid from the reactor outlet 1a mainly contains a cyclic carbonate formed in the reactor 1 and unreacted carbon dioxide, and contains an unreacted epoxide depending on the reaction conditions. A part of the flow is introduced into the circulation path 2 as described above, and the remaining portion discharged from the discharge flow path 3 may be sent to, for example, a separation and purification mechanism (not shown).

The discharge path 3 is configured as any suitable pipe. The material constituting the pipe is not particularly limited, but is preferably SUS in terms of excellent corrosion resistance.

Further, a control valve 15 is provided in the discharge path 3. By the control valve 15, the amount of liquid introduced into the circulation path 2 and circulated in the system and the amount of liquid discharged from the discharge path 3 can be adjusted.

<Second embodiment>

Next, a manufacturing apparatus (second manufacturing apparatus) for a cyclic carbonate according to a second embodiment of the present invention will be described. Description of the same portions of the second manufacturing apparatus as those of the above-described first manufacturing apparatus will be omitted.

The production apparatus of the present embodiment includes a fixed-bed multi-stage reactor in which two or more adiabatic reactors similar to the reactor 1 are connected in series, and the circulation path is included in the multi-stage reactor of the self-fixed bed. At least a portion of the liquid mixed fluid exiting the outlet of the last stage reactor is returned to the first stage reactor included in the fixed bed multistage reactor.

In the present invention, as shown in the examples described later, the amount of the catalyst relative to the amount of cyclic carbonate produced is not substantially affected by the number of reactors, and is substantially constant. Therefore, the manufacturing apparatus of the present embodiment can easily enhance the productivity by adding a reactor.

The production apparatus of the present embodiment further preferably includes an epoxide supply mechanism that continuously supplies the liquid or the solution to at least one of the flow paths connecting the reactors included in the fixed bed multistage reactor. And an mixing mechanism for mixing the epoxide supplied by the epoxide supply mechanism and the liquid mixed fluid flowing into the flow path in the flow path.

According to this configuration, the epoxide can be supplied separately to the plurality of reactors, and the amount of the epoxide supplied to the first-stage reactor can be reduced, and the heat generation of the reactor can be lowered to suppress the deterioration of the catalyst. Further, by continuously supplying liquid or solution epoxide in all the flow paths connecting the reactors, it is equal to the reactor which is mixed in all the flow paths connecting the respective reactors and introduced into the next stage. The inlet allows the exothermic heat caused by the reaction to be dispersed to all the reactors, and it is more preferable to adopt such a constitution.

Further, as the manufacturing apparatus of the present embodiment, it is preferable that at least one of the flow paths connecting the reactors included in the fixed-bed multi-stage reactor has a liquid state which flows into the flow path by indirect heat exchange. A fluid exchange heat removal mechanism for heat removal.

By adopting such a configuration, the heat of reaction generated in the reactor of the preceding stage can be easily removed, and the temperature in the reactor of the next stage can be easily controlled to a desired range (substantially the reaction temperature). Moreover, since the heat of reaction is cooled and removed by indirect heat exchange in all the flow paths connecting the reactors, heat removal can be performed more efficiently, and thus, Jia uses this composition.

Fig. 2 is a view schematically showing an example of a manufacturing apparatus of a cyclic carbonate using a fixed-bed multi-stage reactor according to a second embodiment of the present invention.

The apparatus for producing a cyclic carbonate shown in Fig. 2 comprises a fixed-bed multi-stage reactor in which three adiabatic reactors (reactor 1, reactor 21, and reactor 31) are connected in series, and the fixed-bed multi-stage reactor A flow path 22 from the outlet 1a of the first stage reactor (reactor 1) toward the inlet 21b of the second stage reactor (reactor 21), and the second stage reactor outlet 21a toward the third stage reactor are provided. The flow path 32 of the inlet 31b of the (reactor 31). Similarly to the process shown in Fig. 1, a portion of the liquid mixed fluid flowing out of the third stage reactor outlet 31a is introduced into the first stage reactor inlet 1b via the circulation path 2.

Similarly to the circulation path 2, the flow path 22 and the flow path 32 are configured as any suitable piping. The material constituting the pipe is not particularly limited, and is preferably SUS in terms of excellent corrosion resistance.

Similarly to the reactor 1, the reactor 21 and the reactor 31 may be configured to be filled with a heterogeneous catalyst for reacting the epoxide with carbon dioxide, but a tubular reactor is preferred. Further, the material constituting the reactor 21 and the reactor 31 is not particularly limited, and is preferably SUS in terms of excellent corrosion resistance. Further, by using an inexpensive adiabatic reactor as the reactor 21 and the reactor 31, the equipment cost can be greatly reduced.

Further, when the reactor 21 and the reactor 31 are filled with a heterogeneous catalyst, glass beads or the like may be filled before and after the catalyst.

Further, similarly to the manufacturing apparatus of the first embodiment, the apparatus for producing a cyclic carbonate shown in Fig. 2 includes an epoxide supply mechanism 8 for continuously supplying a liquid or solution epoxide. Further, in the manufacturing apparatus, in addition to the circulation path 2, the control valves 16, 26, and 36 are disposed in each of the flow path 22 and the flow path 32 so that the epoxide is supplied into the flow path.

With this configuration, the epoxide as the reaction raw material is supplied to the liquid mixed fluid flowing through the circulation path 2, the flow path 22, and the flow path 32 in a liquid or solution state.

Further, the supply amounts of the epoxide supplied to the reactors 1, 21, and 31 can be controlled by the control valves 16, 26, 36, respectively.

Further, instead of arranging the control valves 16, 26, 36, an epoxide supply mechanism may be separately disposed in each flow path. In this case, the supply amount of the epoxide supplied to each reactor can be separately controlled by a separate epoxide supply mechanism.

Further, each of the flow paths 22 and 32 includes heat exchange mechanisms 24 and 34 that remove heat from the liquid mixed fluid flowing into the flow path by indirect heat exchange.

By providing the heat exchange mechanisms 24, 34 by the flow paths 22, 32, the heat of reaction generated in the reactor of the previous stage can be easily removed, and the temperature in the reactor of the next stage can be easily controlled to the desired range ( Substantially the reaction temperature).

As the heat exchange mechanisms 24 and 34, as in the heat exchange mechanism 4, any heat exchanger can be used as long as the reaction heat can be removed by lowering the temperature of the liquid mixed fluid passing through the mechanism. Specific examples thereof include a multi-tube cylindrical heat exchanger, a double-tube heat exchanger, a plate heat exchanger, an air cooler, a rinse cooler, a coil heat exchanger, a spiral heat exchanger, and the like, and a double pipe. Heat exchangers, air coolers, and rinsing coolers are particularly suitable and preferred because of the relatively small flow of circulating fluid and high pressure operation. Further, the total heat transfer coefficient of the heat exchangers is preferably about 200 kcal/(m ² hrK) or more.

Further, the flow paths 22 and 32 are provided with mixing mechanisms 20 and 30, respectively. The supplied epoxide and the liquid mixed fluid flowing into the flow path are mixed in the flow path by the mixing mechanisms 20 and 30.

As the mixing mechanisms 20 and 30, an in-line mixer such as a static mixer is preferred because the apparatus is simple.

Further, in the apparatus for producing a cyclic carbonate shown in Fig. 2, the heat exchange means 24, the epoxide inflow part, and the mixing means 20 in the flow path 22 are directed from the outlet 1a of the first stage reactor to the second stage reactor. The inlet 21b is provided in the order of the heat exchange mechanism 24, the epoxide inflow portion, and the mixing mechanism 20. Moreover, the heat exchange mechanism 34 and the epoxide inflow in the flow path 32 The portion and the mixing mechanism 30 are provided in the order of the heat exchange mechanism 34, the epoxide inflow portion, and the mixing mechanism 30 from the outlet 21a of the second stage reactor toward the inlet 31b of the third stage reactor.

By being arranged in this order, the liquid mixed fluid can be efficiently removed, uniformly mixed with the epoxide and efficiently, and supplied to the next reactor.

Moreover, with such a configuration, the temperature difference between the outlet temperature and the inlet temperature of each reactor can be widened without causing deterioration of the catalyst, and the reaction can be efficiently carried out at a high reaction rate in all the reactors. .

Moreover, the manufacturing apparatus of this embodiment is not limited to the manufacturing apparatus shown in FIG. In Fig. 2, a manufacturing apparatus of a fixed-bed multi-stage reactor in which three adiabatic reactors 1, 21, and 31 are connected in series is illustrated, but the number of the adiabatic reactors may be two or more. The number of the adiabatic reactors included in the fixed-bed multi-stage reactor is preferably from 2 to 10, more preferably from 2 to 6, more preferably from 2 to 4.

Further, in the multi-stage adiabatic reactor, a flow path bypassing each of the reactors can be provided, whereby the production amount can be appropriately adjusted, and the catalyst can be replaced while continuing production.

Further, the order of connection of the reactors can be changed by appropriately changing the flow path between the reactors, and the reaction can be performed in an optimized order in accordance with the deterioration state of the catalyst.

Further, the amount of the epoxide introduced into each adiabatic reactor, the carbon dioxide content of the raw material mixed fluid, the amount of the catalyst charged in each adiabatic reactor, and the cyclic carbonate which is circulated to each adiabatic reactor/ The ratio (mass ratio) of the epoxide is the same as that of the first embodiment.

[(2) Method for producing cyclic carbonate]

Next, a method for producing the cyclic carbonate of the present invention will be described.

The method for producing a cyclic carbonate of the present invention can be carried out by using the production apparatus of the present invention as described above in the first production apparatus or the second production apparatus. Further, a mixed fluid containing a raw material of an epoxide and carbon dioxide is continuously supplied to an adiabatic reactor filled with a heterogeneous catalyst to At least a portion of the liquid mixed fluid flowing out of the reactor outlet (in the case of a fixed bed multistage reactor, the final stage reactor outlet) is circulated to a recycle path back to the reactor, and the heat of reaction is removed in the circulation path to the circulating fluid The epoxide and carbon dioxide are continuously supplied while being mixed while being mixed in the flow path.

The adiabatic reactor (in the case of using a fixed-bed multi-stage reactor, refers to each adiabatic reactor included in the multi-stage reactor; the temperature is described below), the inlet temperature (reaction temperature) is the reaction rate, the reaction From the viewpoint of efficiency, it is preferably 60° C. or higher, more preferably 70° C. or higher, further preferably 80° C. or higher, further preferably 90° C. or higher, further preferably 100° C. or higher, and particularly preferably 110° C. or higher. Further, from the viewpoint of suppressing thermal decomposition and preventing deactivation of the catalyst life, it is preferably 160 ° C or lower, more preferably 150 ° C or lower, further preferably 140 ° C or lower, and further preferably 130 ° C or lower. Particularly preferred is below 120 °C.

Further, the temperature of the outlet of the adiabatic reactor is preferably 80 ° C or higher, more preferably 90 ° C or higher, further preferably 100 ° C or higher, further preferably 180 ° C or lower, more preferably 160 ° C or lower, and further Good is below 140 °C.

The temperature difference between the outlet temperature of the reactor and the inlet temperature is preferably 10 ° C or higher, more preferably 20 ° C or higher, further preferably 30 ° C or higher, and more preferably 80 ° C or lower, more preferably 70 ° C or lower. It is preferably 60 ° C or lower, and particularly preferably 50 ° C or lower. Further, it is preferable to set the outlet temperature to the inlet temperature.

Furthermore, since the exotherm per unit throughput is fixed (for example, in the case of synthesizing ethyl carbonate from ethylene oxide and carbon dioxide, the heat of reaction is about 100 kJ/mol), the inlet temperature of the adiabatic reactor is The above temperature difference can be adjusted by the flow ratio of the epoxide to the cyclic carbonate.

Further, as the reaction pressure, it is preferable to prevent gasification of carbon dioxide and epoxide, and it is preferably 1 to 15 MPa in terms of economical efficiency of the apparatus. Further, in terms of the yield of the cyclic carbonate, it is preferred to react in the vicinity of the critical pressure of carbon dioxide (7.38 MPa) to suppress the bias in the reactor due to the gasification of carbon dioxide, and more preferably The reaction is carried out at a pressure exceeding the critical pressure. Specifically, it is preferably reacted at 7 to 10 MPa, more preferably at 7.4 to 9 MPa.

In the following, a case where the apparatus for producing a cyclic carbonate according to the first embodiment of the present invention is used will be described with reference to Fig. 1, and a method for producing the cyclic carbonate of the present invention will be specifically described.

The production method of the present invention is preferably a method of first circulating a cyclic carbonate in the above-described production apparatus of the present invention before the supply of carbon dioxide or an epoxide, and establishing the reactor 1 and the circulation path. The cycle between 2. As the cyclic carbonate, a circulating fluid of the previous batch (for example, a circulating fluid after gas-liquid separation) or a cyclic carbonate produced by the production method of the present invention may be used, and a commercially available cyclic carbonate may also be used.

Specific examples of the method for establishing the above-described cycle include introducing a preheated cyclic carbonate into the gas-liquid separation mechanism 11 and passing it to the heat exchange mechanism 5 and the reactor 1 by the pressure increasing mechanism 12. , circulation path 2, heat exchange mechanism 4 liquid supply cycle. Further, a circulating fluid previously stored in the batch before the gas-liquid separation mechanism 11 may be used. In either case, it is preferred to adjust the reactor inlet temperature by the heat exchange mechanism 5.

Then, the carbon dioxide supply mechanism 6 controls the supply amount while supplying carbon dioxide into the circulation path 2. The carbon dioxide is circulated in the process in a state of being completely mixed with the cyclic carbonate, that is, completely dissolved by the mixing mechanism 9.

The remaining carbon dioxide which is not dissolved in the cyclic carbonate is separated by the gas-liquid separation mechanism 11.

The remaining carbon dioxide is discharged from the upper portion of the gas-liquid separation mechanism 11, and by the residual gas and pressure control mechanism 14, the pressure of the gas-liquid separation mechanism 11 is controlled to be lower than the pressure of the reactor 1 (hence, the pressure of the mixing mechanism 9) ) The pressure. The differential pressure between the gas-liquid separation mechanism 11 and the reactor 1 is preferably 0.1 MPa or more, more preferably 0.3 MPa or more, still more preferably 0.5 MPa or more, and more preferably 1.0 MPa or less.

The reactor can be separated by separating the remaining gas at a pressure lower than the pressure of the reactor 1. (1) Supplying carbon dioxide dissolved in the cyclic carbonate which is less likely to cause vaporization, and preventing the bias flow in the reactor 1.

Then, the circulating liquid after the gas-liquid separation is pressurized to a desired pressure (substantially a reaction pressure), and an epoxide and an optional additive are supplied. The epoxide is supplied to the circulation path by controlling the supply amount by the epoxide supply mechanism 8, and is stirred by the mixing mechanism 10, whereby a uniform raw material mixed fluid is formed.

The additive is supplied to the circulation path by controlling the supply amount by the additive supply mechanism 7. The supply position of the additive is not particularly limited. However, since the supply amount of the additive is usually small, it may be supplied upstream of the above-described mixing mechanism 10, and it is not necessary to separately prepare a mixing mechanism.

Continuous production is started by supplying the raw material mixed fluid containing the epoxide to the reactor 1 and bringing it into contact with the catalyst filled in the reactor 1.

Further, as described in the second embodiment, a fixed bed multistage reactor in which a plurality of adiabatic reactors are connected in series may be used as the reactor. In the case where an adiabatic reactor is added, at least a part of the liquid mixed fluid flowing out from the outlet of the last stage reactor is introduced to the circulation path 2 which is returned to the inlet of the first stage reactor.

In this case, it is preferable to continuously supply the epoxide to the at least one of the flow paths connecting the reactors included in the fixed bed multistage reactor, and to supply the liquid or solution epoxide continuously. The epoxide supplied by the epoxide supply step and the liquid mixed fluid flowing into the flow path are mixed in the flow path. Further, it is more preferable to continuously supply a liquid or solution epoxide to all the flow paths connecting the reactors, and to mix them in all the connection channels connected between the respective reactors and introduce them into the next stage. Entrance.

Further, it is preferable to remove heat from the liquid mixed fluid flowing into at least one of the flow paths connecting the reactors included in the fixed-stage multi-stage reactor by indirect heat exchange, and more preferably to connect each The heat of reaction is removed by indirect heat exchange cooling in all the flow paths between the reactors.

The liquid mixed fluid from the reactor outlet 1a (in the case of a multi-stage reactor, the final stage reactor outlet) mainly comprises a cyclic carbonate formed in the reactor and unreacted carbon dioxide, depending on the reaction conditions, including Unreacted epoxide. As described above, a part thereof is introduced into the circulation path 2, and the heat of reaction is removed by cooling by the heat exchange mechanism 4.

The remaining portion is sent from the discharge path 3 to the next step as needed (separation and purification steps). The discharge amount from the discharge path 3 is adjusted by the control valve 15 in such a manner that the amount of oil in the system is fixed.

As a separation and purification step, a step of decomposing a liquid mixed fluid to separate carbon dioxide and an epoxide, compressing the discharged gas, and recycling the carbon dioxide may be applied; and carbon dioxide is removed by distillation, crystallization, adsorption, or the like. The step of refining the crude cyclic carbonate after the epoxide, and the like.

[Examples]

Hereinafter, the present invention will be described in detail by way of examples, but the invention is not limited to the examples. Further, the analysis method used in the examples is as follows.

(1) Fluorescence X-ray analysis

The amount of bromine and phosphorus modified by the catalyst was determined by fluorescent X-ray analysis. The analysis conditions are as follows.

Device: Product name "System3270" (manufactured by Rigaku Motor Co., Ltd.)

Measurement conditions: Rh bulb, tube voltage 50kV, tube current 50mV, vacuum environment, detector: SC (Scintillation Counter, scintillation counter), F-PC (Flow Proportional Counter)

(2) Thermogravimetric measurement

The measurement of the thermal weight of the catalyst is carried out using a differential thermogravimetric weight measuring device. The analysis conditions are as follows.

Device: Machine name "TG-DTA6200" (manufactured by SII NanoTechnology Co., Ltd.)

Sample amount: 14 mg (the amount of the sample ground by the mortar was placed in an aluminum pan)

Measurement range, temperature rise temperature: room temperature (25 ° C) → temperature rise at 5 ° C / min → hold at 50 ° C for 3 hours → increase temperature at 0.5 ° C / min → hold at 250 ° C for 3 hours

Environment: 50mL/min under nitrogen gas flow

(3) Gas chromatography

The composition analysis of the reaction liquid was carried out by gas chromatography. The analysis conditions are as follows.

Device: Product name "GC-2010Plus" (made by Shimadzu Corporation)

Detector: FID (Flame Ionization Detector)

INJ temperature: 150 ° C

DET temperature: 260 ° C

Sample size: 0.3μL

Split ratio: 5

Column: DB-624 (60m, 0.32mmID, 1.8μm, manufactured by Agilent)

Column temperature conditions: hold at 70 ° C for 3 minutes → increase at 5 ° C / min → 120 ° C → increase temperature at 10 ° C / min → hold at 250 ° C for 5 minutes (total 31 minutes)

Catalyst Synthesis Example 1: Synthesis of Silicone Catalyst Modified by Tributylphosphonium Bromide Surface

40 kg of beaded rubber (CARiACT Q-10 (average pore diameter 10 nm, particle diameter 1.2 to 2.4 mm, specific surface area 300 m ² /g) manufactured by FUJI SILYSIA CHEMICAL) and 100 L of xylene were added to a 200 L SUS reaction tank . The azeotropic dehydration of xylene-water was carried out for 2 hours under reflux at 140 ° C to remove the moisture in the silicone. Then, after replacing the inside of the reaction vessel with nitrogen, 4.4 kg of 3-bromopropyltrimethoxydecane was added dropwise. The decaneization reaction was carried out by heating and refluxing it at 135 ° C for 9 hours. The obtained reactant was extracted from the reaction tank, and the catalyst precursor (bromopropylated ruthenium) in the reaction mixture was separated by filtration, and then washed with 40 L of xylene. The amount of bromine modification in the catalyst precursor obtained herein was 0.39 mmol/g.

Then, the obtained catalyst precursor and 100 L of xylene are added to the reaction tank. After nitrogen substitution in the reaction vessel, 9.1 kg of tri-n-butylphosphine was added dropwise. A four-stage deuteration reaction was carried out by heating it directly under reflux for 24 hours.

After the reaction, the reactant was separated by filtration and washed with 40 L of acetone for 6 times. Thereafter, the reactant was dried under reduced pressure at 120 ° C for 1 night under a nitrogen stream to obtain 46 kg of a tributylphosphonium bromide surface-modified tannin. The amount of bromine modification in the catalyst was 0.32 mmol/g, and the amount of phosphorus modification was 0.33 mmol/g.

Reference Example 1: Thermogravimetric Determination of Catalyst

The thermogravimetric measurement of the catalyst obtained in Catalyst Synthesis Example 1 was carried out. The results are shown in Fig. 3.

As shown in Fig. 3, thermal decomposition of the catalyst was observed from a temperature of 146 ° C or higher, and 1-bromobutane was detected as a decomposition product. Based on the results, the reactor upper limit temperature of the following examples was set to 140 °C.

Reference Example 2: Study on the effect of reaction pressure on the yield of ethyl carbonate

400 mg of the catalyst obtained in Catalyst Synthesis Example 1 was added to a 50 mL autoclave containing a stir bar, and dried under reduced pressure at 120 ° C for 1 hour. After the inside of the autoclave was returned to atmospheric pressure and room temperature by nitrogen, 4 mL (60 mmol) of ethylene oxide was added. Then, the carbon dioxide was temporarily filled to 1.5 MPaG, and then the inside of the autoclave was heated to 100 ° C while stirring at 800 rpm, and the internal pressure was adjusted to a range of 3.0 to 18.3 MPa by further filling with carbon dioxide. Inside, the reaction was carried out for 1 hour. After cooling after completion of the reaction, the remaining carbon dioxide was released to release the pressure in the autoclave. The obtained reaction liquid was analyzed by a gas chromatograph to determine the yield of ethyl carbonate. The results are shown in Fig. 4.

As shown in Fig. 4, the relationship between the reaction pressure and the yield of the ethyl carbonate showed that the vicinity of the critical pressure of carbon dioxide was used as the upward convexity of the peak. From the viewpoint of the results and the viewpoint of suppressing gasification of carbon dioxide, the reaction pressure of the following examples was set to 8 MPa.

Example 1: Manufacture of carbonic acid ethyl ester using a continuous manufacturing apparatus

In the apparatus shown in FIG. 1, two tubes each having a heat exchange mechanism 4, 5 are used. The heat exchanger, the pump for the supply mechanisms 6, 7, and 8 and the pressure increasing mechanism 12, and the static mixer of the mixing mechanisms 9, 10, as the gas-liquid separation tank of the gas-liquid separation mechanism 11, as the pressure control mechanism The apparatus of the back pressure valve of 13, 14 is made of ethylene carbonate.

The reactor 1 obtained by the catalyst synthesis example 1 was filled with 530 g (1000 mL) of the catalyst 1 having an inner diameter of 50 mm, a length of 100 cm, and a volume of 2000 mL, and the particle diameter of the total of 1560 g (1000 mL) was 4mm glass beads.

Then, 5.0 kg of preheated and melted ethyl carbonate was initially introduced into the gas-liquid separation tank 11, and the pump 12 was used to transfer the heat exchanger 5, the static mixer 10, the reactor 1, the circulation path 2, and the heat exchange. The static mixer 9 and the static mixer 9 were fed at a flow rate of 2050 g/hr. At this time, the reactor inlet temperature was adjusted to 100 ° C by the heat exchanger 5.

Then, carbon dioxide was supplied by the pump 6 at a flow rate of 53 g/hr. At this time, carbon dioxide was stirred by the static mixer 9, and it was circulated in a state of being completely mixed with ethyl carbonate, that is, completely dissolved. Since the remaining carbon dioxide which is not dissolved in the ethyl carbonate is separated by the gas-liquid separation tank 11, the drift in the reactor 1 is prevented. The remaining carbon dioxide is discharged from the upper portion of the gas-liquid separation tank 11, and the pressure of the gas-liquid separation tank 11 is maintained at 7.5 MPaG by the residual gas and the back pressure valve 14.

Then, the pressure of the reactor 1 was adjusted to 8.0 MPaG by the back pressure valve 13. Thus, the pressure difference between the static mixer 9 and the reactor 1 and the gas-liquid separation tank 11 was adjusted to 0.5 MPa. Further, the liquid after the gas-liquid separation was pressurized by the pump 12 to 8.0 MPaG, and supplied to the reactor 1. By this operation, carbon dioxide which is completely dissolved in ethyl carbonate and which is less likely to be vaporized is supplied to the reactor 1.

Further, the saturated solubility of carbon dioxide to ethyl carbonate in the reactor inlet 1b condition (8 MPa, 100 ° C) was approximately 12% by mass, and the solubility of carbon dioxide to the circulating fluid after gas-liquid separation was approximately 11% by mass.

Then, after the pump 7 was supplied with 2-bromoethanol as an additive for maintaining the performance of the catalyst at a flow rate of 0.035 g/hr, the pump 8 was supplied with epoxy at a flow rate of 44 g/hr. Ethane, whereby continuous production (cyclic carbonate/epoxide ratio (mass ratio) = 40) circulating to the reactor 1 was started. Further, 2-bromoethanol and ethylene oxide were mixed with ethylene carbonate by a static mixer 10, and supplied to the reactor 1.

The opening degree of the control valve 15 is adjusted so that the liquid level of the gas-liquid separation tank 11 is the liquid level in the system, and the produced ethylene carbonate is extracted from the discharge path 3. The extracted ethyl carbonate flow rate was approximately 88 g/hr.

Further, since ethylene oxide was not detected in the gas discharged from the upper portion of the gas-liquid separation tank 11, the conversion ratio of ethylene oxide was calculated by the following formula.

Conversion rate X = {(feed ethylene oxide flow rate) - (extraction of ethylene oxide flow)} / (feed ethylene oxide flow) × 100

The concentration of ethylene oxide in the extracted ethyl carbonate was calculated to be 0.29%, and the conversion of ethylene oxide was 99.4%.

Further, the reaction was continued for 260 hours, but the outlet temperature of the reactor was maintained in the range of 115 to 118 ° C, and the conversion rate due to catalyst deactivation was not observed. That is, it was confirmed that the temperature of the reactor was controlled to be appropriate by indirect heat exchange, and the catalyst performance was maintained even in a long-term operation.

Example 2: One reactor simulation

In the embodiment shown in Fig. 1, the relationship between the reactor temperature, the amount of ethylene carbonate extended, and the amount of catalyst was simulated by the following conditions. The results are shown in Table 1.

Simulation software: PRO II (Invensys Process Systems) physical property estimation algorithm SRK-M

The apparatus shown in Fig. 1 includes a double-tube heat exchanger as the heat exchange mechanisms 4 and 5, and a pump for the supply mechanisms 6, 7, 8 and the pressure increasing mechanism 12 as raw materials, as the mixing mechanism 9, 10 static mixer, as a gas-liquid separation tank of the gas-liquid separation mechanism 11, as a device for the back pressure valve of the pressure control mechanisms 13, 14

Year of carbonic acid ethyl ester (8000 hours) Production capacity: 1000 tons

Ethylene oxide supply (pump 8): 63kg / hr

2-Bromoethanol supply (pump 7): 0.05kg/hr

Carbon dioxide supply (pump 6): 63kg / hr

Ethylene oxide conversion rate: 99%

Number of reactors: 1

Reactor pressure: 8MPa

Adiabatic reactor inlet temperature: 60 ° C, 70 ° C, 80 ° C, 90 ° C, 100 ° C, 110 ° C, 120 ° C, 130 ° C, and 135 ° C

Adiabatic reactor upper limit temperature (adiabatic reactor outlet temperature): 140 ° C

ΔT: temperature difference between reactor outlet 1a and reactor inlet 1b

EC/EO cycle dilution ratio: the ethylene carbonate flow rate at the reactor inlet 1b divided by the ethylene oxide supply (63 kg/hr)

Example 3: 3 reactor simulations

In the embodiment shown in Fig. 2, the relationship between the reactor temperature, the amount of ethylene carbonate extended, and the amount of catalyst was simulated by the following conditions. The results are shown in Table 1.

Simulation software: PRO II (Invensys Process Systems) physical property estimation algorithm SRK-M

Device: The apparatus shown in Fig. 2 includes a double-tube heat exchanger as the heat exchange mechanisms 4, 5, 24, and 34, and a pump for the supply mechanisms 6, 7, and 8 and the pressure increasing mechanism 12 as raw materials. A static mixer of the mixing mechanism 9, 10, 20, 30, as a gas-liquid separation tank of the gas-liquid separation mechanism 11, as a device for the back pressure valve of the pressure control mechanisms 13, 14

Year of carbonic acid ethyl ester (8000 hours) Production capacity: 1000 tons

Ethylene oxide supply (control valve 16): 21kg / hr

(Control valve 26): 21kg/hr

(Control valve 36): 21kg/hr

2-Bromoethanol supply (pump 7): 0.05kg/hr

Carbon dioxide supply (pump 6): 64kg / hr

Ethylene oxide conversion rate: 99%

Number of reactors: 3

Reactor pressure: 8MPa

Adiabatic reactor inlet temperature: 110 ° C, 120 ° C, 130 ° C and 135 ° C

Adiabatic reactor upper limit temperature (adiabatic reactor outlet temperature): 140 ° C

ΔT: temperature difference between reactor outlet 1a and reactor inlet 1b

EC/EO cycle dilution ratio: the total ethylene carbonate flow rate at the inlet 1b of the reactor divided by the total ethylene oxide supply (63 kg/hr)

Example 4: Two reactor simulations

In the case where the number of reactors is two, that is, in the embodiment shown in Fig. 2, the embodiment in which the control valve 36, the flow path 32, the reactor 31, the heat exchange mechanism 34, and the mixing mechanism 30 are removed is carried out. The reactor was simulated.

Specifically, the relationship between the reactor temperature, the amount of ethylene carbonate extended, and the amount of catalyst was simulated by the following conditions. The results are shown in Table 1.

Simulation software: PRO II (Invensys Process Systems) physical property estimation algorithm SRK-M

Apparatus: In the apparatus of Embodiment 2, the apparatus for removing the control valve 36, the flow path 32, the reactor 31, the double tube heat exchanger 34, and the static mixer 30

Year of carbonic acid ethyl ester (8000 hours) Production capacity: 1000 tons

Ethylene oxide supply (control valve 16): 31.5kg/hr

(Control valve 26): 31.5kg/hr

2-Bromoethanol supply (pump 7): 0.05kg/hr

Carbon dioxide supply (pump 6): 64kg / hr

Ethylene oxide conversion rate: 99%

Number of reactors: 2

Reactor pressure: 8MPa

Adiabatic reactor inlet temperature: 90 ° C, 100 ° C, 110 ° C, 120 ° C, 130 ° C, and 135 ° C

Adiabatic reactor upper limit temperature (adiabatic reactor outlet temperature): 140 ° C

ΔT: temperature difference between reactor outlet 1a and reactor inlet 1b

EC/EO cycle dilution ratio: the total ethylene carbonate flow rate at the reactor inlet 1b divided by the total ethylene oxide supply (63 kg / hr)

As shown in Table 1, the inlet temperature can be controlled by the cycle ratio of ethyl carbonate/ethylene oxide at the inlet of the reactor, and by optimizing this, it can be compared with 1000 tons/year of ethyl carbonate. The production amount is about 400~500L, and a relatively small amount of catalyst is reacted. Therefore, the reaction can be carried out by a small reactor, which can reduce the equipment cost.

Further, in the present invention, since the amount of the catalyst relative to the amount of cyclic carbonate production is not affected by the number of reactors, it is substantially fixed, so that in the case of enhancing productivity, only the reactor, the heat exchanger, and the static are sequentially added. The mixer can be used, and the ability to achieve economical excellence can be enhanced. Therefore, there is no need to dispose of equipment and no need to double invest in equipment.

1‧‧‧reactor

1a‧‧‧reactor outlet

1b‧‧‧reactor inlet

2‧‧‧Circular path

3‧‧‧Drainage path

4‧‧‧Hot Exchange Agency

5‧‧‧Hot Exchange Agency

6‧‧‧CO2 supply agency

7‧‧‧Additive supply mechanism

8‧‧‧epoxide supply mechanism

9‧‧‧Mixed institutions

10‧‧‧Mixed institutions

11‧‧‧ gas-liquid separation mechanism

12‧‧‧Booster

13‧‧‧Pressure control agency

14‧‧‧ Pressure Control Agency

15‧‧‧Control valve

Claims (10)

A device for producing a cyclic carbonate, characterized by comprising: an adiabatic reactor for filling a heterogeneous catalyst for reacting an epoxide with carbon dioxide; and a circulation path for allowing a liquid to flow out from an outlet of the reactor At least a part of the mixed fluid is returned to the reactor; a carbon dioxide supply mechanism continuously supplies carbon dioxide in a liquid or supercritical state to the circulation path; and an epoxide supply mechanism continuously supplies the liquid to the circulation path Or a solution-like epoxide; and the circulation path includes: a heat exchange mechanism that removes heat from the circulating fluid by indirect heat exchange; a mixing mechanism that supplies carbon dioxide supplied by the carbon dioxide supply mechanism to the circulating fluid Mixing in the path; a gas-liquid separation mechanism for decompressing the circulating fluid containing carbon dioxide obtained by the mixing mechanism for gas-liquid separation treatment; and a pressure increasing mechanism for boosting the circulating fluid after the gas-liquid separation treatment To a specific pressure; and a mixing mechanism that is supplied by the above epoxide supply mechanism Epoxides with the circulating fluid in the mixing path. The apparatus for producing a cyclic carbonate according to claim 1, wherein the reactor is configured as a fixed bed multistage reactor in which two or more adiabatic reactors are connected in series; the circulation path is such that the reactor is from the last stage. At least a portion of the liquid mixed fluid exiting the outlet is returned to the first stage reactor. The apparatus for producing a cyclic carbonate of claim 2, which further comprises: An epoxide supply mechanism for continuously supplying a liquid or solution epoxide to at least one of the flow paths connecting the reactors included in the fixed bed multistage reactor; and a mixing mechanism for lending The epoxide supplied from the epoxide supply mechanism and the liquid mixed fluid flowing into the flow path are mixed in the flow path. The apparatus for producing a cyclic carbonate according to claim 2, wherein at least one of the flow paths connecting the reactors included in the fixed-bed multi-stage reactor includes inflow to the flow path by indirect heat exchange A heat exchange mechanism for removing heat from a liquid mixed fluid. The apparatus for producing a cyclic carbonate according to any one of claims 1 to 4, wherein each of the above mixing mechanisms is an in-line mixer. A method for producing a cyclic carbonate, characterized in that a mixed fluid containing a raw material of an epoxide and carbon dioxide is continuously supplied to an adiabatic reactor filled with a heterogeneous catalyst, and a liquid mixture which flows out from an outlet of the reactor is mixed. At least a portion of the fluid is introduced to the circulation path to return to the reactor; and includes a heat exchange step for removing heat from the circulating fluid by indirect heat exchange, and a carbon dioxide supply step of continuously supplying the liquid to the circulation path Or carbon dioxide in a supercritical state; a mixing step of mixing the carbon dioxide supplied by the carbon dioxide supply step with the circulating fluid in a path; a gas-liquid separation step of the carbon dioxide-containing cycle obtained by the mixing step The fluid is depressurized, and the remaining carbon dioxide of the gasification is subjected to gas-liquid separation treatment; the pressure increasing step is to pressurize the circulating fluid after the gas-liquid separation to a specific pressure; and the epoxide supply step is continuously supplied to the circulation path. Liquid or solution epoxide; and And a mixing step of mixing the epoxide supplied by the epoxide supply step with the circulating fluid in the path. The method for producing a cyclic carbonate according to claim 6, wherein the reactor is configured as a fixed-bed multi-stage reactor in which two or more adiabatic reactors are connected in series; the circulation path is an outlet from the last reactor At least a portion of the effluent liquid mixed fluid is returned to the first stage reactor. The method for producing a cyclic carbonate according to claim 7, further comprising: an epoxide supply step of continuously supplying at least one of the flow paths connecting the reactors included in the fixed bed multistage reactor a liquid or solution epoxide; and a mixing step of mixing the epoxide supplied by the epoxide supply step with the liquid mixed fluid flowing into the flow path in the flow path. The method for producing a cyclic carbonate according to claim 7, which comprises a heat exchange step of inflowing to a flow path between the reactors connected to the fixed bed multistage reactor by indirect heat exchange The liquid mixed fluid of at least one of the flow paths removes heat. The method for producing a cyclic carbonate according to any one of claims 6 to 9, wherein each of the above mixing steps is carried out using an in-line mixer.