WO2012132031A1 - Control method for safe continuous manufacturing of polycarbonate oligomer - Google Patents

Control method for safe continuous manufacturing of polycarbonate oligomer Download PDF

Info

Publication number
WO2012132031A1
WO2012132031A1 PCT/JP2011/064829 JP2011064829W WO2012132031A1 WO 2012132031 A1 WO2012132031 A1 WO 2012132031A1 JP 2011064829 W JP2011064829 W JP 2011064829W WO 2012132031 A1 WO2012132031 A1 WO 2012132031A1
Authority
WO
WIPO (PCT)
Prior art keywords
phosgene
reactor
oligomer
gas
polycarbonate
Prior art date
Application number
PCT/JP2011/064829
Other languages
French (fr)
Japanese (ja)
Inventor
和宏 関口
広明 茂木
俊之 安田
Original Assignee
出光興産株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 出光興産株式会社 filed Critical 出光興産株式会社
Priority to KR1020137025131A priority Critical patent/KR101823724B1/en
Publication of WO2012132031A1 publication Critical patent/WO2012132031A1/en

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G64/00Macromolecular compounds obtained by reactions forming a carbonic ester link in the main chain of the macromolecule
    • C08G64/20General preparatory processes
    • C08G64/22General preparatory processes using carbonyl halides
    • C08G64/24General preparatory processes using carbonyl halides and phenols
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G64/00Macromolecular compounds obtained by reactions forming a carbonic ester link in the main chain of the macromolecule
    • C08G64/20General preparatory processes
    • C08G64/36General preparatory processes using carbon monoxide
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L69/00Compositions of polycarbonates; Compositions of derivatives of polycarbonates

Definitions

  • the present invention relates to a control method for safe continuous production of polycarbonate oligomer.
  • an interfacial method in which dihydric phenols (bisphenols) and phosgene are directly reacted and a transesterification method in which bisphenols and diphenyl carbonate are reacted under a solvent-free condition are known.
  • the interface method has become the mainstream from the viewpoint of obtaining a polycarbonate with good quality (see, for example, Patent Document 1).
  • bisphenols, alkali compounds such as sodium hydroxide and phosgene are used as raw materials for polycarbonate, and a terminal terminator (molecular weight regulator) or the like is added as necessary.
  • phosgene is generally blown into an alkaline aqueous solution of bisphenols to produce a polycarbonate oligomer having a reactive chloroformate group.
  • Polycarbonate is produced by reacting with an alkaline aqueous solution of bisphenols.
  • Patent Document 2 discloses a method of storing liquefied phosgene obtained by distillation purification of phosgene and producing a polycarbonate using the liquefied phosgene.
  • phosgene is highly toxic, it is not desirable to store it from the viewpoint of safety.
  • phosgene storage tank is damaged due to corrosion or the like, there is a risk that phosgene leaks.
  • Such risks can be reduced by installing phosgene abatement equipment, but it takes time to remove phosgene due to the large amount of phosgene held, but to eliminate it in a short time. Requires large-scale equipment and is costly.
  • Patent Document 3 discloses a continuous production method of a polycarbonate oligomer that is directly used for producing a polycarbonate oligomer without liquefying phosgene gas obtained by reacting chlorine and carbon monoxide. According to this method, the amount of phosgene retained in the system can be reduced as compared with the method using liquefied phosgene.
  • the problem to be solved by the present invention is that in the method of continuously producing a polycarbonate oligomer during the production of polycarbonate, even when an abnormality occurs, the apparatus is automatically stopped and harmful phosgene is leaked out of the system. It is to provide a method for abatement without doing.
  • Step (1) for continuously producing phosgene gas containing unreacted carbon monoxide by supplying chlorine and carbon monoxide to the phosgene reactor, and phosgene gas continuously produced in step (1), divalent A method for controlling polycarbonate oligomer continuous production comprising the step (2) of continuously producing a reaction mixture containing a polycarbonate oligomer by continuously supplying an alkaline aqueous solution of phenol and an organic solvent to an oligomer reactor, When the following conditions (i) and / or (ii) are satisfied, the supply of chlorine and carbon monoxide in the step (1) is stopped, the supply of phosgene gas to the oligomer reactor is stopped, and the phosgene gas A control method for continuous production of polycarbonate oligomers, wherein a toxic gas containing is transferred to a detoxifying means and rendered harmless.
  • the method of the present invention in the continuous production of polycarbonate oligomer by the interfacial method, even if an abnormal reaction in the phosgene reactor occurs due to a cooling problem of the phosgene reactor, the phosgene reactor is damaged, etc. Without causing an accident, the supply of chlorine and carbon monoxide as phosgene raw materials and the supply of phosgene to the oligomer reactor are automatically stopped, and the phosgene in the system is automatically controlled to be transferred to the abatement means, A polycarbonate oligomer can be produced safely without phosgene leaking out of the system.
  • the method for controlling the continuous production of polycarbonate oligomer of the present invention is as follows.
  • the cooling water flow rate (F1) of the phosgene reactor and the outlet temperature (T1) of the phosgene reactor cooling water are constantly monitored.
  • the conditions (i) and / or (ii) are satisfied, the supply of chlorine and carbon monoxide as phosgene raw materials and the supply of phosgene to the oligomer reactor are automatically stopped, and the phosgene in the system is used as a detoxifying means. It is a method of automatically controlling to transfer.
  • thermometers In the viewpoint of monitoring for local temperature rise in the phosgene reactor, it is ideal to install multiple thermometers in the phosgene reactor and directly measure the temperature inside, especially the catalyst layer. It is. However, when multiple thermometers are installed in the phosgene reactor, especially in the catalyst layer, not only problems such as increased costs and increased maintenance load occur, but phosgene gas leaks from the location where the thermometer is installed. Because it is dangerous, it is not realistic. Therefore, in the present invention, the cooling water flow rate (F1) and the phosgene reactor cooling water outlet temperature (T1) of the phosgene reactor are constantly monitored, and it is confirmed whether there is any deviation from the steady-state conditions. Monitor for abnormal temperature rise.
  • the method for controlling the continuous production of polycarbonate oligomer of the present invention is applied to an interfacial method in which a dihydric phenol and phosgene are directly reacted, and is applied in a continuous reaction system.
  • the method for continuously producing a polycarbonate oligomer in the present invention includes a step (1) of continuously supplying phosgene gas containing unreacted carbon monoxide by supplying chlorine and carbon monoxide to a phosgene reactor, and the above-described step.
  • Step (2) for continuously producing a reaction mixture containing a polycarbonate oligomer by continuously supplying the phosgene gas continuously produced in (1), an alkaline aqueous solution of dihydric phenol and an organic solvent to an oligomer reactor. It is a method including.
  • Step (1) is a step of continuously producing phosgene gas containing unreacted carbon monoxide by supplying chlorine and carbon monoxide to the phosgene reactor.
  • carbon monoxide is preferably produced by reacting coke, petroleum, natural gas, alcohol or the like with oxygen and purified to a purity of 95% by volume or more.
  • the sulfur component content is preferably 50 ppm or less.
  • the chlorine (carbon monoxide) ratio (molar ratio) is preferably 1: 1.01 to 1: 1.3, more preferably 1: 1.02 to 1: 1.2.
  • the reaction can be carried out by a known method described in, for example, Japanese Patent Publication No. 55-14044.
  • a catalyst mainly composed of activated carbon can be used. Since the phosgene production reaction is an exothermic reaction, it is necessary to cool the phosgene reactor. It is preferable to keep the reactor internal temperature at 350 ° C. or lower.
  • the phosgene production conditions in the step (1) are appropriately determined depending on the scale of the apparatus and the production amount. As an example, preferable conditions for producing about 4 kg of phosgene per hour are described below, but the present invention is not limited thereto.
  • a preferable flow rate of carbon monoxide is 1.1 to 1.3 kg / h, and a preferable flow rate of chlorine is 2.7 to 2.9 kg / h.
  • a preferable flow rate of the cooling water is 78 to 82 kg / h, a preferable temperature is 89 to 91 ° C., and a preferable pressure is 0.18 to 0.22 MPaG.
  • the cooling water outlet temperature is preferably 92 to 94 ° C. Here, it is assumed that the cooling water is fed under conditions that do not boil due to the heat of the phosgenation reaction.
  • the phosgene gas obtained in step (1) usually contains unreacted carbon monoxide.
  • the content of carbon monoxide in the phosgene gas is preferably 1 to 30% by volume, more preferably 2 to 20% by volume, from the viewpoint of cost and the quality of the polycarbonate oligomer. That is, phosgene gas having a purity of 99 to 70% by volume is preferable.
  • Step (2) the phosgene gas continuously produced in the step (1), the alkaline aqueous solution of dihydric phenol and the organic solvent are continuously supplied to the oligomer reactor, and the reaction mixture containing the polycarbonate oligomer is continuously added. Manufacturing process.
  • Examples of raw materials in the production of polycarbonate include phosgene gas, dihydric phenols (bisphenols), alkali compounds used to dissolve dihydric phenols, and organic solvents. Polyhydric phenols and other additives may be used.
  • the phosgene gas the phosgene gas continuously produced in the step (1) is used.
  • dihydric phenols 2,2-bis (4-hydroxyphenyl) propane (common name, bisphenol A; BPA) is preferable from the viewpoint of the physical properties of the polycarbonate.
  • dihydric phenols other than bisphenol A include bis (4-hydroxyphenyl) methane; 1,1-bis (4-hydroxyphenyl) ethane; bis (1,2-bis (4-hydroxyphenyl) ethane, etc.
  • dihydric phenols may be used individually by 1 type, and may mix and use 2 or more types.
  • Sodium hydroxide is preferred as the alkaline compound used to dissolve the dihydric phenols.
  • the organic solvent only needs to dissolve the polycarbonate oligomer, and examples thereof include chlorinated solvents such as methylene chloride, dichloroethane, chloroform, chlorobenzene, and carbon tetrachloride, and cyclic oxy compounds such as dioxane.
  • chlorinated solvents such as methylene chloride, dichloroethane, chloroform, chlorobenzene, and carbon tetrachloride, and cyclic oxy compounds such as dioxane.
  • a chlorinated solvent is preferable, and methylene chloride is particularly preferably used from the viewpoint of the solubility of the polycarbonate oligomer.
  • solvents such as alkanes called poor solvents may be used as long as the solubility of the polycarbonate oligomer is not lowered.
  • An organic solvent may be used individually by 1 type, and may mix and use 2 or more types.
  • Examples of the monohydric phenol used as the molecular weight regulator include phenol, p-cresol, p-tert-butylphenol, p-tert-octylphenol, p-cumylphenol, nonylphenol and the like. Of these, p-tert-butylphenol and phenol are preferable from the viewpoints of cost and availability.
  • a polymerization catalyst such as a tertiary amine or a quaternary amine can be used as necessary.
  • TEA triethylamine
  • the oligomer reactor a continuous reaction type reactor is used, and a reactor having a tubular structure having a mixing section for mixing reaction raw materials is preferably used.
  • the oligomer reactor is installed in the building and isolated from the outside. The inside of the building is constantly changing air, and the ventilation air inside is sent to the abatement means by a blower or the like.
  • the amount of raw material supplied to the oligomer reactor and the reaction conditions in the step (2) are appropriately determined depending on the scale of the apparatus and the production amount. As an example, preferable conditions for producing about 200 kg of polycarbonate oligomer per hour will be described below, but the present invention is not limited thereto.
  • a preferable flow rate of the phosgene gas obtained by the step (1) is 3.7 to 4.1 kg / h.
  • the temperature of the phosgene gas is preferably in the range of the boiling point of phosgene (7.8 ° C.) to 90 ° C.
  • a sodium hydroxide aqueous solution of bisphenol A is preferable, and is adjusted and supplied in advance to have a predetermined concentration.
  • the preferred bisphenol A concentration is 12.5 to 14.0% by mass, and the preferred sodium hydroxide concentration is 5.1 to 6.1% by mass.
  • a preferred flow rate of the aqueous sodium hydroxide solution of bisphenol A is 42 to 46 kg / h.
  • the flow rate of the organic solvent such as methylene chloride is preferably 20 to 24 kg / h.
  • step (2) a reaction mixture containing a polycarbonate oligomer having a chloroformate group is obtained.
  • the properties of the polycarbonate oligomer are not particularly limited, and the reaction conditions may be set as appropriate so that the properties are appropriate, but the molecular weight measured by a VPO (vapor pressure osmometer) is about 600 to 5000. Those are preferred.
  • the reaction mixture containing the polycarbonate oligomer is a mixture of an organic phase in which the polycarbonate oligomer is dissolved in the organic solvent and an aqueous phase containing an alkaline aqueous solution.
  • a polycarbonate can be produced by introducing this reaction mixture into a condensation reactor and subjecting it to a condensation reaction.
  • the reaction solution is washed by a known method, concentrated, and pulverized to obtain a powdery polycarbonate, which is further pelletized by processing with an extruder or the like. can do.
  • a predetermined amount of phosgene gas, an aqueous alkali solution of dihydric phenol, and an organic solvent are continuously supplied to the oligomer reactor.
  • the supply pressure (P1) of the phosgene gas and the inlet pressure (P2) in the oligomer reactor are appropriately set depending on the size, shape, etc. of the phosgene reactor and the oligomer reactor.
  • the supply pressure (P1) of the phosgene gas is 0.4 to 0.5 MPaG
  • the inlet pressure (P2) in the oligomer reactor is 0.15 to 0.35 MPaG
  • the pressure difference between the two (P1 ⁇ P2) is 0.105 MPa to 0.35 MPa.
  • Condition (i) is a case where the cooling water flow rate (F1) of the phosgene reactor is reduced by 25% or more from the steady state. A predetermined amount of carbon monoxide and chlorine are continuously supplied to the phosgene reactor. However, since the phosgene production reaction is an exothermic reaction, it is necessary to cool the phosgene reactor. Even if the production volume, reaction conditions, cooling water temperature, etc. have not changed from the steady state, if the cooling water flow rate is insufficient due to problems with the cooling water supply pump, etc., the heat removal will decrease and the temperature inside the phosgene reactor will rise.
  • the automatic system is started when the cooling water flow rate (F1) of the phosgene reactor is reduced by 25% or more from the steady state.
  • F1 cooling water flow rate
  • the automatic system May be set when the cooling water flow rate (F1) of the phosgene reactor is reduced by 49% or more from the steady state, and may be set when the flow rate is further lowered by 54% or more from the steady state. .
  • Condition (ii) is a case where the phosgene reactor cooling water outlet temperature (T1) is increased by 5 ° C. or more from the steady state. A predetermined amount of carbon monoxide and chlorine are continuously supplied to the phosgene reactor. However, since the phosgene production reaction is an exothermic reaction, it is necessary to cool the phosgene reactor. If the cooling water outlet temperature rises due to abnormal phosgenation reaction even though the production volume, reaction conditions, cooling water temperature, etc.
  • the temperature inside the phosgene reactor rises, and as a result, A certain amount of carbon tetrachloride is formed and is undesirable because the carbon tetrachloride is mixed into the polycarbonate product.
  • the reaction temperature becomes uncontrollable in the phosgene reactor, the phosgene reactor becomes locally hot, the phosgene reactor is damaged, and there is a risk that phosgene leaks out of the system. Therefore, in the present invention, from the viewpoint of safety, the automatic system is started when the phosgene reactor cooling water outlet temperature (T1) rises by 5 ° C. or more from the steady state.
  • the automatic system May be set when the phosgene reactor cooling water outlet temperature (T1) rises by 10 ° C. or more from the steady state, and may further be set when the temperature rises by 25 ° C. or more from the steady state. .
  • Toxic gas containing phosgene gas in the system is transferred to an abatement means and rendered harmless.
  • This is an operation of detoxifying the phosgene gas in the system from the viewpoint of higher safety, in addition to preventing the increase and leakage of phosgene by the above operations (a) and (b) and confining it in the system. .
  • the detoxifying means is equipment for detoxifying toxic gas containing phosgene gas with a detoxifying agent, and a known one can be used. Specific examples include a spraying device for a pesticide, an absorption tower for bringing a toxic gas into contact with the pesticide, and the like. In addition, tower-type detoxification equipment described in JP-A-6-319946, JP-A-2005-305414 and the like can also be used.
  • alkaline substances are used as a detoxifying agent.
  • the alkaline substance used as the detoxifying agent is not particularly limited, but sodium hydroxide and potassium hydroxide are generally used. These are usually used as an aqueous solution.
  • the structure of the detoxification tower is not particularly limited, but as a typical example, the detoxifying agent is sprayed from the top of the tower in the form of a shower, etc. There are those that are removed by contact with gas.
  • a filler such as Raschig ring may be filled between the detoxifying agent injection port and the gas inflow port.
  • the number of detoxification towers is not particularly limited, and the toxic gas concentration in the detoxification treatment gas is preferably reduced to a level that is not detected so that the concentration is less than or equal to a predetermined concentration defined by environmental standards. Designed to.
  • Detoxification means always operate in case of unforeseen circumstances even if no toxic gas leaks.
  • the ventilation air in the building where the oligomer reactor is installed is sent to an abatement means by a blower or the like to be rendered harmless and then released to the outside.
  • FIG. 1 is a process diagram showing an outline of a preferred embodiment of the method for controlling the continuous production of polycarbonate oligomer of the present invention.
  • phosgene production raw material chlorine and carbon monoxide are supplied to the phosgene reactor through a control valve, and phosgene gas is produced in the phosgene reactor. Since the reaction is exothermic, the phosgene reactor is cooled by cooling water. Phosgene gas (reaction product) containing unreacted carbon monoxide is introduced into the oligomer reactor through a control valve.
  • an alkaline aqueous solution of dihydric phenol specifically, for example, a sodium hydroxide aqueous solution of bisphenol A
  • an organic solvent specifically, for example, methylene chloride
  • the control valve provided in the supply path of chlorine and carbon monoxide automatically controls these flow rates, and the control valve provided in the supply path to the oligomer reactor of phosgene gas supplies to the oligomer reactor. The supply pressure of phosgene gas is controlled.
  • the cooling water flow rate (F1) of the phosgene reactor is constantly monitored using a flow meter, and the phosgene reactor cooling water outlet temperature (T1) is constantly monitored using a thermometer, and the value is an automatic control device. (Dotted arrow in the figure).
  • a control valve provided in the supply path of chlorine and carbon monoxide from the automatic control device, a control valve provided in the supply path to the oligomer reactor of phosgene gas, and a control valve provided in the flow path to the detoxification device Signals are sent all at once (thick solid arrows in the figure).
  • the control valve provided in the supply path for chlorine and carbon monoxide is closed by a signal from the automatic control device, and the supply of chlorine and carbon monoxide is stopped.
  • control valve provided in the supply path to the oligomer reactor of phosgene gas is closed, and the supply of phosgene gas to the oligomer reactor is stopped.
  • the control valve provided in the flow path to the abatement device is closed during normal operation, but is opened by a signal from the automatic control device, and toxic gas including phosgene gas in the system is transferred to the abatement device. . In the abatement apparatus, toxic gas including phosgene gas is rendered harmless.
  • shutoff valve for stopping fluid supply may be provided in addition to the control valve.
  • Example 1-1 (Automatic control device) As shown in FIG. 1, when the cooling water flow rate (F1) of the phosgene reactor is reduced by 25% or more from the steady state (condition (i)), or the phosgene reactor cooling water outlet temperature (T1) is 5 ° C. from the steady state. In the case of the above increase (condition (ii)), the control valve provided in the supply path for chlorine and carbon monoxide and the control valve provided in the supply path to the oligomer reactor for phosgene gas are closed and detoxified.
  • An automatic control device was designed to perform control so as to open a control valve provided in the flow path to the device.
  • abatement apparatus As the abatement apparatus, an abatement tower having a tower diameter of 600 mm and a packed bed height of 10 m packed with Cascade Mini Ring (CMR) (trade name, manufactured by Matsui Machine Co., Ltd.) was used. A sodium hydroxide aqueous solution having a concentration of 10% by mass was circulated at 2 m 3 / h as a detoxifying agent in the detoxifying tower. Sodium hydroxide aqueous solution was supplied from the top of the tower, and toxic gas was supplied from the bottom.
  • CMR Cascade Mini Ring
  • phosgene reactor a shell and tube reactor in which a commercially available granular activated carbon (coconut shell activated carbon pulverized to a diameter of 1.2 to 1.4 mm) was filled in a tube was used. Carbon monoxide 1.2 kg / h and chlorine 2.8 kg / h were supplied to the phosgene reactor to produce phosgene gas 3.9 kg / h. 90 ° C. water was passed through the shell portion of the phosgene reactor at 80 kg / h to remove reaction heat. At this time, the reactor outlet temperature of water was 93 ° C., and the pressure was 0.2 MPaG.
  • oligomer reactor a tubular reactor having an inner diameter of 6 mm and a length of 30 m was used.
  • the oligomer reactor was immersed in a cooling bath at 20 ° C.
  • the phosgene gas was continuously supplied from the upstream phosgene production process to the oligomer reactor, and the supply pressure of the phosgene gas supplied to the oligomer reactor was set to 0.45 MPaG.
  • phosgene gas 3.9 kg / h
  • bisphenol A (BPA) dissolved in 6% strength by weight sodium hydroxide aqueous solution, obtained by dissolving 13.5% by weight BPA aqueous sodium hydroxide 44 kg / h
  • chloride A methylene chloride solution (0.46 kg / h) of p-tert-butylphenol having a concentration of 25% by mass for adjusting the molecular weight was supplied at a rate of 22 kg / h to prepare a polycarbonate oligomer solution.
  • the inlet pressure in the oligomer reactor was 0.20 MPaG.
  • the cooling water flow rate (F1) of the phosgene reactor was intentionally reduced by 25% to 60 kg / h.
  • the automatic control device stops the supply of chlorine and carbon monoxide to the phosgene reactor and the supply of phosgene gas to the oligomer reactor, and the phosgene gas generated in the phosgene reactor is removed from the abatement device. It was transferred to.
  • phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
  • Example 1-2 A polycarbonate oligomer was produced in the same manner as in Example 1-1 except that the cooling water flow rate (F1) of the phosgene reactor was intentionally reduced by 50% to 40 kg / h.
  • the cooling water flow rate (F1) of the phosgene reactor was intentionally reduced by 50% to 40 kg / h.
  • the supply of chlorine and carbon monoxide to the phosgene reactor was stopped and the supply of phosgene gas to the oligomer reactor was stopped by the automatic controller, and the phosgene reaction
  • the phosgene gas generated in the vessel was transferred to the abatement device.
  • phosgene When components were measured for the gas discharged from the exit of the detoxification tower, phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
  • Example 1-3 A polycarbonate oligomer was produced in the same manner as in Example 1-1 except that the cooling water flow rate (F1) of the phosgene reactor was intentionally reduced by 55% to 36 kg / h.
  • the supply of chlorine and carbon monoxide to the phosgene reactor was stopped and the supply of phosgene gas to the oligomer reactor was stopped by the automatic controller, and the phosgene reaction
  • the phosgene gas generated in the vessel was transferred to the abatement device.
  • phosgene When components were measured for the gas discharged from the exit of the detoxification tower, phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
  • Comparative Example 1-1 A polycarbonate oligomer was produced in the same manner as in Example 1-1 except that the automatic controller was not used. However, if automatic control is not performed, a local temperature rise is expected in the phosgene reactor, and if the operation is continued, the temperature inside the phosgene reactor locally exceeds the design temperature, and the phosgene reactor is damaged and the phosgene reactor is damaged. This operation was stopped because it was assumed that would leak out of the system.
  • Example 2-1 A polycarbonate oligomer was produced in the same manner as in Example 1-1 except that the phosgene reactor cooling water outlet temperature (T1) was intentionally increased by 5 ° C. As a result, as in Example 1-1, the supply of chlorine and carbon monoxide to the phosgene reactor was stopped and the supply of phosgene gas to the oligomer reactor was stopped by the automatic controller, and the phosgene reaction The phosgene gas generated in the vessel was transferred to the abatement device. When components were measured for the gas discharged from the exit of the detoxification tower, phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
  • T1 phosgene reactor cooling water outlet temperature
  • Example 2-2 A polycarbonate oligomer was produced in the same manner as in Example 2-1, except that the phosgene reactor cooling water outlet temperature (T1) was intentionally increased by 10 ° C.
  • T1 phosgene reactor cooling water outlet temperature
  • the automatic control device stopped the supply of chlorine and carbon monoxide to the phosgene reactor and the supply of phosgene gas to the oligomer reactor, and the phosgene reaction
  • the phosgene gas generated in the vessel was transferred to the abatement device.
  • phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
  • Example 2-3 A polycarbonate oligomer was produced in the same manner as in Example 2-1, except that the phosgene reactor cooling water outlet temperature (T1) was intentionally increased by 25 ° C.
  • the automatic control device stopped the supply of chlorine and carbon monoxide to the phosgene reactor and the supply of phosgene gas to the oligomer reactor, and the phosgene reaction
  • the phosgene gas generated in the vessel was transferred to the abatement device.
  • phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
  • Comparative Example 2-1 A polycarbonate oligomer was produced in the same manner as in Example 2-1, except that the automatic controller was not used. However, if automatic control is not performed, a local temperature rise is expected in the phosgene reactor, and if the operation is continued, the temperature inside the phosgene reactor locally exceeds the design temperature, and the phosgene reactor is damaged and the phosgene reactor is damaged. This operation was stopped because it was assumed that would leak out of the system.
  • a polycarbonate oligomer can be continuously produced safely.
  • the automatic control automatically stops the production and supply of phosgene and renders toxic gases including phosgene gas harmless. No poison gas leaks out of the system.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Polyesters Or Polycarbonates (AREA)

Abstract

A control method for safely manufacturing a polycarbonate oligomer, wherein the control method automatically detoxifies toxic phosgene without leakage to outside the system in the event of an abnormality

Description

ポリカーボネートオリゴマーの安全な連続製造のための制御方法Control method for safe continuous production of polycarbonate oligomers
 本発明は、ポリカーボネートオリゴマーの安全な連続製造のための制御方法に関する。 The present invention relates to a control method for safe continuous production of polycarbonate oligomer.
 一般に、ポリカーボネートの製造方法としては、二価フェノール類(ビスフェノール類)とホスゲンとを直接反応させる界面法、ビスフェノール類とジフェニルカーボネートとを無溶媒条件下で反応させるエステル交換法が知られているが、品質が良好なポリカーボネートが得られる点から、界面法が主流となっている(例えば特許文献1を参照)。
 界面法では、ポリカーボネートの原料としては、ビスフェノール類、水酸化ナトリウム等のアルカリ化合物及びホスゲンが用いられ、必要に応じて末端停止剤(分子量調節剤)等が添加される。また、ポリカーボネートの工業的製造プラントでは、一般に、ビスフェノール類のアルカリ水溶液にホスゲンを吹き込んで反応性のクロロフォーメート基を有するポリカーボネートオリゴマーを生成させ、この生成と同時にあるいは逐次的に、さらにポリカーボネートオリゴマーとビスフェノール類のアルカリ水溶液とを反応させることにより、ポリカーボネートが製造されている。
In general, as a method for producing polycarbonate, an interfacial method in which dihydric phenols (bisphenols) and phosgene are directly reacted and a transesterification method in which bisphenols and diphenyl carbonate are reacted under a solvent-free condition are known. The interface method has become the mainstream from the viewpoint of obtaining a polycarbonate with good quality (see, for example, Patent Document 1).
In the interfacial method, bisphenols, alkali compounds such as sodium hydroxide and phosgene are used as raw materials for polycarbonate, and a terminal terminator (molecular weight regulator) or the like is added as necessary. Further, in an industrial production plant for polycarbonate, phosgene is generally blown into an alkaline aqueous solution of bisphenols to produce a polycarbonate oligomer having a reactive chloroformate group. Polycarbonate is produced by reacting with an alkaline aqueous solution of bisphenols.
 特許文献2には、ホスゲンを蒸留精製して得られる液化ホスゲンを貯蔵し、該液化ホスゲンを用いてポリカーボネートを製造する方法が開示されている。
 しかしながら、ホスゲンは毒性が高いため、貯蔵しておくことは安全性の観点から望ましくなく、例えば液化ホスゲン貯槽が腐食等により破損した場合にはホスゲンが漏洩するというリスクが存在する。そのようなリスクは、ホスゲン除害設備を設置することで低減することができるが、ホスゲンの保有量が多いためにホスゲンを除害するのに時間がかかる一方、短時間で除害するためには大規模の設備が必要となりコストがかかる。
Patent Document 2 discloses a method of storing liquefied phosgene obtained by distillation purification of phosgene and producing a polycarbonate using the liquefied phosgene.
However, since phosgene is highly toxic, it is not desirable to store it from the viewpoint of safety. For example, when a liquefied phosgene storage tank is damaged due to corrosion or the like, there is a risk that phosgene leaks. Such risks can be reduced by installing phosgene abatement equipment, but it takes time to remove phosgene due to the large amount of phosgene held, but to eliminate it in a short time. Requires large-scale equipment and is costly.
 特許文献3には、塩素及び一酸化炭素を反応させて得られるホスゲンガスを液化することなく、そのままポリカーボネートオリゴマーの製造に用いるポリカーボネートオリゴマーの連続製造方法が開示されている。この方法によれば、液化ホスゲンを用いる方法に比べて、系内のホスゲンの保有量が少なく済む。 Patent Document 3 discloses a continuous production method of a polycarbonate oligomer that is directly used for producing a polycarbonate oligomer without liquefying phosgene gas obtained by reacting chlorine and carbon monoxide. According to this method, the amount of phosgene retained in the system can be reduced as compared with the method using liquefied phosgene.
特開2004-331916号公報JP 2004-331916 A 特開2001-261321号公報JP 2001-261321 A 国際公開第2007/083721号International Publication No. 2007/083721
 塩素及び一酸化炭素をホスゲン反応器内で反応させてホスゲンガスを生成させる際、反応器内部は発熱反応を起こすため、外部からの冷却によりホスゲン反応器内を一定の温度に保っておく必要がある。何らかのトラブルにより冷却が十分でなくなると、ホスゲン反応器内の反応温度が制御不能の状態となり、局所的にホスゲン反応器が高温となって、破損し、系外に漏洩する可能性もある。また、さらに反応器内の温度が高くなりすぎると、その結果として副生成物である四塩化炭素が多量に生成し、該四塩化炭素がポリカーボネート製品中に混入してくる。このことは、例えば光ディスク等の基板として使用する場合、記録膜に悪影響を及ぼすため望ましくない。
 しかしながら、上記特許文献のいずれにも、これらの問題が生じた場合については想定されておらず、有害なホスゲンを系外に漏洩することなく除害しつつポリカーボネートを製造する方法については開示されていない。
When chlorine and carbon monoxide are reacted in a phosgene reactor to generate phosgene gas, the reactor interior generates an exothermic reaction, so it is necessary to keep the phosgene reactor at a constant temperature by external cooling. . If the cooling becomes insufficient due to some trouble, the reaction temperature in the phosgene reactor becomes uncontrollable, and the phosgene reactor becomes locally hot and may be damaged and leak out of the system. Further, when the temperature in the reactor becomes too high, a large amount of carbon tetrachloride as a by-product is produced as a result, and the carbon tetrachloride is mixed into the polycarbonate product. This is not desirable when used as a substrate such as an optical disk because it adversely affects the recording film.
However, none of the above-mentioned patent documents is supposed about the case where these problems occur, and a method for producing polycarbonate while removing harmful phosgene without leaking out of the system is disclosed. Absent.
 本発明が解決しようとする課題は、ポリカーボネートを製造する際のポリカーボネートオリゴマーを連続的に製造する方法において、異常時においても、自動的に装置を停止し、かつ、有害なホスゲンを系外に漏洩することなく除害する方法を提供することにある。 The problem to be solved by the present invention is that in the method of continuously producing a polycarbonate oligomer during the production of polycarbonate, even when an abnormality occurs, the apparatus is automatically stopped and harmful phosgene is leaked out of the system. It is to provide a method for abatement without doing.
 前記課題は、下記のポリカーボネートオリゴマー連続製造の制御方法によって解決される。
 塩素及び一酸化炭素をホスゲン反応器に供給し未反応の一酸化炭素を含有するホスゲンガスを連続的に製造する工程(1)、並びに前記工程(1)で連続的に製造されたホスゲンガス、二価フェノールのアルカリ水溶液及び有機溶媒をオリゴマー反応器に連続的に供給して、ポリカーボネートオリゴマーを含有する反応混合物を連続的に製造する工程(2)を含むポリカーボネートオリゴマー連続製造の制御方法であって、
 下記の条件(i)及び/又は(ii)を満たす場合に、前記工程(1)における塩素及び一酸化炭素の供給を停止すると共に、オリゴマー反応器へのホスゲンガスの供給を停止させ、かつ、ホスゲンガスを含む有毒ガスを除害手段に移送して無害化する、ポリカーボネートオリゴマー連続製造の制御方法。
 条件(i):ホスゲン反応器の冷却水流量(F1)が定常時から25%以上低下した場合。
 条件(ii):ホスゲン反応器冷却水出口温度(T1)が定常時から5℃以上上昇した場合。
The said subject is solved by the control method of the following polycarbonate oligomer continuous manufacture.
Step (1) for continuously producing phosgene gas containing unreacted carbon monoxide by supplying chlorine and carbon monoxide to the phosgene reactor, and phosgene gas continuously produced in step (1), divalent A method for controlling polycarbonate oligomer continuous production comprising the step (2) of continuously producing a reaction mixture containing a polycarbonate oligomer by continuously supplying an alkaline aqueous solution of phenol and an organic solvent to an oligomer reactor,
When the following conditions (i) and / or (ii) are satisfied, the supply of chlorine and carbon monoxide in the step (1) is stopped, the supply of phosgene gas to the oligomer reactor is stopped, and the phosgene gas A control method for continuous production of polycarbonate oligomers, wherein a toxic gas containing is transferred to a detoxifying means and rendered harmless.
Condition (i): The cooling water flow rate (F1) of the phosgene reactor is reduced by 25% or more from the steady state.
Condition (ii): The phosgene reactor cooling water outlet temperature (T1) rises by 5 ° C. or more from the steady state.
 本発明の方法によれば、界面法によるポリカーボネートオリゴマーの連続製造において、ホスゲン反応器の冷却トラブルにより、ホスゲン反応器内の異常反応が起きた場合であっても、ホスゲン反応器が破損する等の事故を起こすことなく、ホスゲン原料である塩素及び一酸化炭素の供給並びにオリゴマー反応器へのホスゲンの供給を自動停止すると共に、系内のホスゲンを除害手段に移送するように自動制御して、ホスゲンを系外に漏洩することなく安全にポリカーボネートオリゴマーを製造することができる。 According to the method of the present invention, in the continuous production of polycarbonate oligomer by the interfacial method, even if an abnormal reaction in the phosgene reactor occurs due to a cooling problem of the phosgene reactor, the phosgene reactor is damaged, etc. Without causing an accident, the supply of chlorine and carbon monoxide as phosgene raw materials and the supply of phosgene to the oligomer reactor are automatically stopped, and the phosgene in the system is automatically controlled to be transferred to the abatement means, A polycarbonate oligomer can be produced safely without phosgene leaking out of the system.
本発明のポリカーボネートオリゴマー連続製造の制御方法の好ましい一実施態様の概略を示す工程図である。It is process drawing which shows the outline of one preferable embodiment of the control method of the polycarbonate oligomer continuous manufacture of this invention.
 本発明のポリカーボネートオリゴマー連続製造の制御方法は、界面法によるポリカーボネートオリゴマーの連続製造において、ホスゲン反応器の冷却水流量(F1)及びホスゲン反応器冷却水出口温度(T1)を常時監視し、後述する条件(i)及び/又は(ii)を満たす場合に、ホスゲン原料である塩素及び一酸化炭素の供給並びにオリゴマー反応器へのホスゲンの供給を自動停止すると共に、系内のホスゲンを除害手段に移送するように自動制御する方法である。
 なお、ホスゲン反応器内において局所的な温度上昇がないか監視するという観点からは、ホスゲン反応器内に複数の温度計を設置して内部、特に触媒層の温度を直接測定することが理想的である。しかし、ホスゲン反応器内、特に触媒層に複数の温度計を設置する場合、コストアップやメンテナンスの負荷が増大する等の問題が生じるだけでなく、温度計が設置された箇所からホスゲンガスが漏洩する危険があるため、現実的ではない。そのため、本発明では、ホスゲン反応器の冷却水流量(F1)及びホスゲン反応器冷却水出口温度(T1)を常時監視し、定常時の条件から逸脱がないか確認することでホスゲン反応器内の異常な温度上昇がないか監視する。
The method for controlling the continuous production of polycarbonate oligomer of the present invention is as follows. In the continuous production of polycarbonate oligomer by the interface method, the cooling water flow rate (F1) of the phosgene reactor and the outlet temperature (T1) of the phosgene reactor cooling water are constantly monitored. When the conditions (i) and / or (ii) are satisfied, the supply of chlorine and carbon monoxide as phosgene raw materials and the supply of phosgene to the oligomer reactor are automatically stopped, and the phosgene in the system is used as a detoxifying means. It is a method of automatically controlling to transfer.
From the viewpoint of monitoring for local temperature rise in the phosgene reactor, it is ideal to install multiple thermometers in the phosgene reactor and directly measure the temperature inside, especially the catalyst layer. It is. However, when multiple thermometers are installed in the phosgene reactor, especially in the catalyst layer, not only problems such as increased costs and increased maintenance load occur, but phosgene gas leaks from the location where the thermometer is installed. Because it is dangerous, it is not realistic. Therefore, in the present invention, the cooling water flow rate (F1) and the phosgene reactor cooling water outlet temperature (T1) of the phosgene reactor are constantly monitored, and it is confirmed whether there is any deviation from the steady-state conditions. Monitor for abnormal temperature rise.
[ポリカーボネートの製造]
 本発明のポリカーボネートオリゴマー連続製造の制御方法は、二価フェノール類とホスゲンとを直接反応させる界面法に適用され、連続反応方式において適用される。
 本発明におけるポリカーボネートオリゴマーを連続的に製造する方法は、塩素及び一酸化炭素をホスゲン反応器に供給し未反応の一酸化炭素を含有するホスゲンガスを連続的に製造する工程(1)、並びに前記工程(1)で連続的に製造されたホスゲンガス、二価フェノールのアルカリ水溶液及び有機溶媒をオリゴマー反応器に連続的に供給して、ポリカーボネートオリゴマーを含有する反応混合物を連続的に製造する工程(2)を含む方法である。
[Manufacture of polycarbonate]
The method for controlling the continuous production of polycarbonate oligomer of the present invention is applied to an interfacial method in which a dihydric phenol and phosgene are directly reacted, and is applied in a continuous reaction system.
The method for continuously producing a polycarbonate oligomer in the present invention includes a step (1) of continuously supplying phosgene gas containing unreacted carbon monoxide by supplying chlorine and carbon monoxide to a phosgene reactor, and the above-described step. Step (2) for continuously producing a reaction mixture containing a polycarbonate oligomer by continuously supplying the phosgene gas continuously produced in (1), an alkaline aqueous solution of dihydric phenol and an organic solvent to an oligomer reactor. It is a method including.
<工程(1)>
 工程(1)は、塩素及び一酸化炭素をホスゲン反応器に供給し未反応の一酸化炭素を含有するホスゲンガスを連続的に製造する工程である。
 ポリカーボネートオリゴマーの品質の観点から、一酸化炭素は、コークス、石油、天然ガス、アルコール等と酸素とを反応させて製造し、純度95容量%以上に精製したものが好ましい。特に、硫黄成分の含有量が50ppm以下のものが好ましい。また、塩素:一酸化炭素の比率(モル比)は、好ましくは1:1.01~1:1.3、より好ましくは1:1.02~1:1.2である。
 なお、反応は、例えば特公昭55-14044号公報等に記載の公知の方法によって行うことができる。触媒として、活性炭を主成分とする触媒を用いることができる。
 ホスゲン製造反応は発熱反応であるため、ホスゲン反応器を冷却する必要がある。反応器内部温度を350℃以下に保つことが好ましい。
<Step (1)>
Step (1) is a step of continuously producing phosgene gas containing unreacted carbon monoxide by supplying chlorine and carbon monoxide to the phosgene reactor.
From the viewpoint of the quality of the polycarbonate oligomer, carbon monoxide is preferably produced by reacting coke, petroleum, natural gas, alcohol or the like with oxygen and purified to a purity of 95% by volume or more. In particular, the sulfur component content is preferably 50 ppm or less. The chlorine (carbon monoxide) ratio (molar ratio) is preferably 1: 1.01 to 1: 1.3, more preferably 1: 1.02 to 1: 1.2.
The reaction can be carried out by a known method described in, for example, Japanese Patent Publication No. 55-14044. As the catalyst, a catalyst mainly composed of activated carbon can be used.
Since the phosgene production reaction is an exothermic reaction, it is necessary to cool the phosgene reactor. It is preferable to keep the reactor internal temperature at 350 ° C. or lower.
 工程(1)におけるホスゲン製造条件は、装置の規模や生産量等によって適宜決定される。
 例として、1時間当たり約4kgのホスゲンを製造する場合における好ましい条件を以下に記載するが、これに限定されるものではない。一酸化炭素の好ましい流量は1.1~1.3kg/hであり、塩素の好ましい流量は2.7~2.9kg/hである。冷却水の好ましい流量は78~82kg/h、好ましい温度は89~91℃、好ましい圧力は0.18~0.22MPaGである。冷却水出口温度は、好ましくは92~94℃である。ここで、冷却水は、ホスゲン化反応熱によって沸騰しないような条件で送液することを前提としている。
The phosgene production conditions in the step (1) are appropriately determined depending on the scale of the apparatus and the production amount.
As an example, preferable conditions for producing about 4 kg of phosgene per hour are described below, but the present invention is not limited thereto. A preferable flow rate of carbon monoxide is 1.1 to 1.3 kg / h, and a preferable flow rate of chlorine is 2.7 to 2.9 kg / h. A preferable flow rate of the cooling water is 78 to 82 kg / h, a preferable temperature is 89 to 91 ° C., and a preferable pressure is 0.18 to 0.22 MPaG. The cooling water outlet temperature is preferably 92 to 94 ° C. Here, it is assumed that the cooling water is fed under conditions that do not boil due to the heat of the phosgenation reaction.
 工程(1)で得られるホスゲンガスは、通常、未反応の一酸化炭素を含有する。ホスゲンガス中の一酸化炭素の含有量は、コスト及びポリカーボネートオリゴマーの品質の観点から、好ましくは1~30容量%、より好ましくは2~20容量%である。すなわち、純度99~70容量%のホスゲンガスが好ましい。 The phosgene gas obtained in step (1) usually contains unreacted carbon monoxide. The content of carbon monoxide in the phosgene gas is preferably 1 to 30% by volume, more preferably 2 to 20% by volume, from the viewpoint of cost and the quality of the polycarbonate oligomer. That is, phosgene gas having a purity of 99 to 70% by volume is preferable.
<工程(2)>
 工程(2)は、前記工程(1)で連続的に製造されたホスゲンガス、二価フェノールのアルカリ水溶液及び有機溶媒をオリゴマー反応器に連続的に供給して、ポリカーボネートオリゴマーを含有する反応混合物を連続的に製造する工程である。
<Step (2)>
In the step (2), the phosgene gas continuously produced in the step (1), the alkaline aqueous solution of dihydric phenol and the organic solvent are continuously supplied to the oligomer reactor, and the reaction mixture containing the polycarbonate oligomer is continuously added. Manufacturing process.
 ポリカーボネートの製造における原料としては、ホスゲンガス、二価フェノール類(ビスフェノール類)、二価フェノール類を溶解するために使用するアルカリ化合物、有機溶媒が挙げられ、必要に応じて、分子量調節剤としての一価フェノールや、その他の添加剤を使用してもよい。
 ホスゲンガスとしては、前記工程(1)で連続的に製造されたホスゲンガスが用いられる。
Examples of raw materials in the production of polycarbonate include phosgene gas, dihydric phenols (bisphenols), alkali compounds used to dissolve dihydric phenols, and organic solvents. Polyhydric phenols and other additives may be used.
As the phosgene gas, the phosgene gas continuously produced in the step (1) is used.
 二価フェノール類としては、ポリカーボネートの物性の点から、2,2-ビス(4-ヒドロキシフェニル)プロパン(通称、ビスフェノールA;BPA)が好ましい。ビスフェノールA以外の二価フェノール類としては、例えばビス(4-ヒドロキシフェニル)メタン;1,1-ビス(4-ヒドロキシフェニル)エタン;1,2-ビス(4-ヒドロキシフェニル)エタン等のビス(4-ヒドロキシフェニル)アルカン、1,1-ビス(4-ヒドロキシフェニル)シクロヘキサン;1,1-ビス(4-ヒドロキシフェニル)シクロデカン等のビス(4-ヒドロキシフェニル)シクロアルカン、4,4’-ジヒドロキシジフェニル、ビス(4-ヒドロキシフェニル)オキシド、ビス(4-ヒドロキシフェニル)スルフィド、ビス(4-ヒドロキシフェニル)スルホン、ビス(4-ヒドロキシフェニル)スルホキシド、ビス(4-ヒドロキシフェニル)エーテル、ビス(4-ヒドロキシフェニル)ケトン、ハイドロキノン等が挙げられる。これらの二価フェノール類は、一種を単独で用いてもよく、二種以上を混合して用いてもよい。
 二価フェノール類を溶解するために使用するアルカリ化合物としては、水酸化ナトリウムが好適である。
As the dihydric phenols, 2,2-bis (4-hydroxyphenyl) propane (common name, bisphenol A; BPA) is preferable from the viewpoint of the physical properties of the polycarbonate. Examples of dihydric phenols other than bisphenol A include bis (4-hydroxyphenyl) methane; 1,1-bis (4-hydroxyphenyl) ethane; bis (1,2-bis (4-hydroxyphenyl) ethane, etc. 4-hydroxyphenyl) alkane, 1,1-bis (4-hydroxyphenyl) cyclohexane; bis (4-hydroxyphenyl) cycloalkane such as 1,1-bis (4-hydroxyphenyl) cyclodecane, 4,4′-dihydroxy Diphenyl, bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, bis (4 -Hydroxyphenyl) ketone, hydroxy Non etc. are mentioned. These dihydric phenols may be used individually by 1 type, and may mix and use 2 or more types.
Sodium hydroxide is preferred as the alkaline compound used to dissolve the dihydric phenols.
 有機溶媒としては、ポリカーボネートオリゴマーが溶解するものであればよく、例えば、塩化メチレン,ジクロロエタン,クロロホルム,クロロベンゼン,四塩化炭素等の塩素系溶媒、ジオキサン等の環状オキシ化合物等が挙げられる。本発明においては、塩素系溶媒が好ましく、ポリカーボネートオリゴマーの溶解性等の点から塩化メチレンが特に好ましく使用される。上記で挙げた有機溶媒以外にも、ポリカーボネートオリゴマーの溶解性を低下させない範囲であれば、貧溶媒と呼ばれるアルカン類等の溶媒を使用してもよい。
 有機溶媒は、一種を単独で用いてもよく、二種以上を混合して用いてもよい。
The organic solvent only needs to dissolve the polycarbonate oligomer, and examples thereof include chlorinated solvents such as methylene chloride, dichloroethane, chloroform, chlorobenzene, and carbon tetrachloride, and cyclic oxy compounds such as dioxane. In the present invention, a chlorinated solvent is preferable, and methylene chloride is particularly preferably used from the viewpoint of the solubility of the polycarbonate oligomer. In addition to the organic solvents mentioned above, solvents such as alkanes called poor solvents may be used as long as the solubility of the polycarbonate oligomer is not lowered.
An organic solvent may be used individually by 1 type, and may mix and use 2 or more types.
 分子量調節剤として用いる一価フェノールとしては、例えばフェノール、p-クレゾール、p-tert-ブチルフェノール、p-tert-オクチルフェノール、p-クミルフェノール、ノニルフェノール等が挙げられる。中でも、コストや入手の容易性等の観点から、p-tert-ブチルフェノール及びフェノールが好ましい。 Examples of the monohydric phenol used as the molecular weight regulator include phenol, p-cresol, p-tert-butylphenol, p-tert-octylphenol, p-cumylphenol, nonylphenol and the like. Of these, p-tert-butylphenol and phenol are preferable from the viewpoints of cost and availability.
 ポリカーボネートオリゴマーの製造には、必要に応じて、三級アミン、四級アミンなどの重合触媒を使用することもできる。重合触媒としては、TEA(トリエチルアミン)が好ましい。
 オリゴマー反応器としては、連続反応方式の反応器が用いられ、反応原料を混合する混合部を有する管型構造をした反応器が好ましく用いられる。
 なお、オリゴマー反応器は建物内に設置されており、外部と隔離されている。建物内は常時空気の入れ替えを行っており、内部の換気空気はブロア等で除害手段へ送られる。
For the production of the polycarbonate oligomer, a polymerization catalyst such as a tertiary amine or a quaternary amine can be used as necessary. As the polymerization catalyst, TEA (triethylamine) is preferable.
As the oligomer reactor, a continuous reaction type reactor is used, and a reactor having a tubular structure having a mixing section for mixing reaction raw materials is preferably used.
The oligomer reactor is installed in the building and isolated from the outside. The inside of the building is constantly changing air, and the ventilation air inside is sent to the abatement means by a blower or the like.
 工程(2)におけるオリゴマー反応器への原料の供給量や反応条件は、装置の規模や生産量等によって適宜決定される。
 例として、1時間当たり約200kgのポリカーボネートオリゴマーを製造する場合における好ましい条件を以下に記載するが、これに限定されるものではない。工程(1)により得られるホスゲンガスの好ましい流量は3.7~4.1kg/hである。ホスゲンガスの温度は、ホスゲンの沸点(7.8℃)~90℃の範囲が好ましい。二価フェノールのアルカリ水溶液としては、ビスフェノールAの水酸化ナトリウム水溶液が好ましく、予め所定濃度になるように調整され供給される。ビスフェノールAの水酸化ナトリウム水溶液において、好ましいビスフェノールA濃度は12.5~14.0質量%であり、好ましい水酸化ナトリウム濃度は5.1~6.1質量%である。ビスフェノールAの水酸化ナトリウム水溶液の好ましい流量は42~46kg/hである。塩化メチレン等の有機溶媒の流量は、好ましくは20~24kg/hである。
The amount of raw material supplied to the oligomer reactor and the reaction conditions in the step (2) are appropriately determined depending on the scale of the apparatus and the production amount.
As an example, preferable conditions for producing about 200 kg of polycarbonate oligomer per hour will be described below, but the present invention is not limited thereto. A preferable flow rate of the phosgene gas obtained by the step (1) is 3.7 to 4.1 kg / h. The temperature of the phosgene gas is preferably in the range of the boiling point of phosgene (7.8 ° C.) to 90 ° C. As the alkaline aqueous solution of dihydric phenol, a sodium hydroxide aqueous solution of bisphenol A is preferable, and is adjusted and supplied in advance to have a predetermined concentration. In the aqueous sodium hydroxide solution of bisphenol A, the preferred bisphenol A concentration is 12.5 to 14.0% by mass, and the preferred sodium hydroxide concentration is 5.1 to 6.1% by mass. A preferred flow rate of the aqueous sodium hydroxide solution of bisphenol A is 42 to 46 kg / h. The flow rate of the organic solvent such as methylene chloride is preferably 20 to 24 kg / h.
 工程(2)では、クロロフォーメート基を有するポリカーボネートオリゴマーを含有する反応混合物が得られる。上記ポリカーボネートオリゴマーの性状は特に制限されるものではなく、適宜最適な性状となるように反応条件を設定すればよいが、VPO(蒸気圧浸透圧計)で測定した分子量が約600~5000程度であるものが好ましい。 In step (2), a reaction mixture containing a polycarbonate oligomer having a chloroformate group is obtained. The properties of the polycarbonate oligomer are not particularly limited, and the reaction conditions may be set as appropriate so that the properties are appropriate, but the molecular weight measured by a VPO (vapor pressure osmometer) is about 600 to 5000. Those are preferred.
 なお、ポリカーボネートオリゴマーを含有する反応混合物は、ポリカーボネートオリゴマーが前記有機溶媒に溶解した有機相と、アルカリ水溶液を含有する水相の混合物である。この反応混合物を縮合反応器に導入し、縮合反応させることでポリカーボネートを製造することができる。
 また、縮合反応が終了した後、反応溶液を公知の方法で洗浄し、濃縮し、粉末化等を行うことにより粉末状のポリカーボネートを得ることができ、さらに押出機等で処理することによりペレット化することができる。
The reaction mixture containing the polycarbonate oligomer is a mixture of an organic phase in which the polycarbonate oligomer is dissolved in the organic solvent and an aqueous phase containing an alkaline aqueous solution. A polycarbonate can be produced by introducing this reaction mixture into a condensation reactor and subjecting it to a condensation reaction.
In addition, after the condensation reaction is completed, the reaction solution is washed by a known method, concentrated, and pulverized to obtain a powdery polycarbonate, which is further pelletized by processing with an extruder or the like. can do.
[ポリカーボネートオリゴマー連続製造の制御方法]
 オリゴマー反応器には所定量のホスゲンガス、二価フェノールのアルカリ水溶液及び有機溶媒が連続的に供給される。ホスゲンガスの供給圧力(P1)及びオリゴマー反応器内の入口圧力(P2)は、ホスゲン反応器やオリゴマー反応器の大きさ、形状等によって適宜設定されるが、通常、ホスゲンガスの供給圧力(P1)が0.4~0.5MPaG、オリゴマー反応器内の入口圧力(P2)が0.15~0.35MPaG、両者の圧力差(P1-P2)の値が0.105MPa~0.35MPaの差圧となるように連続運転される。
 本発明のポリカーボネートオリゴマー連続製造の制御方法では、ホスゲン反応器の冷却水流量(F1)及びホスゲン反応器冷却水出口温度(T1)について、下記の条件(i)及び/又は(ii)を満たしているかどうか常時監視し、該条件を満たした場合に、自動システムにより、ホスゲンの製造及び供給を停止すると共に、系内のホスゲンガスを含む有毒ガスを除害手段に移送して無害化する。
 条件(i):ホスゲン反応器の冷却水流量(F1)が定常時から25%以上低下した場合。
 条件(ii):ホスゲン反応器冷却水出口温度(T1)が定常時から5℃以上上昇した場合。
[Control method for continuous production of polycarbonate oligomer]
A predetermined amount of phosgene gas, an aqueous alkali solution of dihydric phenol, and an organic solvent are continuously supplied to the oligomer reactor. The supply pressure (P1) of the phosgene gas and the inlet pressure (P2) in the oligomer reactor are appropriately set depending on the size, shape, etc. of the phosgene reactor and the oligomer reactor. Usually, the supply pressure (P1) of the phosgene gas is 0.4 to 0.5 MPaG, the inlet pressure (P2) in the oligomer reactor is 0.15 to 0.35 MPaG, and the pressure difference between the two (P1−P2) is 0.105 MPa to 0.35 MPa. It is continuously operated to become.
In the control method for continuous production of polycarbonate oligomer of the present invention, the following conditions (i) and / or (ii) are satisfied for the cooling water flow rate (F1) and the phosgene reactor cooling water outlet temperature (T1) of the phosgene reactor. Whether or not phosgene is produced and supplied is stopped by an automatic system and a toxic gas containing phosgene gas in the system is transferred to an abatement means to make it harmless.
Condition (i): The cooling water flow rate (F1) of the phosgene reactor is reduced by 25% or more from the steady state.
Condition (ii): The phosgene reactor cooling water outlet temperature (T1) rises by 5 ° C. or more from the steady state.
<条件(i)>
 条件(i)は、ホスゲン反応器の冷却水流量(F1)が定常時から25%以上低下した場合である。
 ホスゲン反応器には所定量の一酸化炭素及び塩素が連続的に供給されるが、ホスゲン生成反応は発熱反応であるため、ホスゲン反応器を冷却する必要がある。生産量、反応条件、冷却水温度等が定常時から変わってないにもかかわらず冷却水供給ポンプ等のトラブルにより冷却水流量が不足すると、除熱量が低下してホスゲン反応器内温度が上昇し、それにより副生成物である四塩化炭素が多量に生成し、該四塩化炭素がポリカーボネート製品中に混入するため望ましくない。また、ホスゲン反応器内で反応温度が制御不能の状態となると、局所的にホスゲン反応器が高温となり、ホスゲン反応器が破損して、系外にホスゲンが漏洩する危険がある。
 そのため、本発明では、安全上の観点から、ホスゲン反応器の冷却水流量(F1)が定常時から25%以上低下した場合に自動システムを起動させる。ただし、一過性のトラブル等により頻繁に自動システムが起動してしまうと、効率よく操業することが難しくなってしまうため、安全性を確保した上で効率よく操業するという観点からは、自動システムが起動する条件は、ホスゲン反応器の冷却水流量(F1)が、定常時から49%以上低下した場合に設定してもよく、更に定常時から54%以上低下した場合に設定してもよい。
<Condition (i)>
Condition (i) is a case where the cooling water flow rate (F1) of the phosgene reactor is reduced by 25% or more from the steady state.
A predetermined amount of carbon monoxide and chlorine are continuously supplied to the phosgene reactor. However, since the phosgene production reaction is an exothermic reaction, it is necessary to cool the phosgene reactor. Even if the production volume, reaction conditions, cooling water temperature, etc. have not changed from the steady state, if the cooling water flow rate is insufficient due to problems with the cooling water supply pump, etc., the heat removal will decrease and the temperature inside the phosgene reactor will rise. , Thereby producing a large amount of carbon tetrachloride as a by-product, which is undesirable because the carbon tetrachloride is mixed in the polycarbonate product. Further, when the reaction temperature becomes uncontrollable in the phosgene reactor, the phosgene reactor becomes locally hot, the phosgene reactor is damaged, and there is a risk that phosgene leaks out of the system.
Therefore, in the present invention, from the viewpoint of safety, the automatic system is started when the cooling water flow rate (F1) of the phosgene reactor is reduced by 25% or more from the steady state. However, if the automatic system is frequently started due to temporary troubles, etc., it will be difficult to operate efficiently. From the viewpoint of operating efficiently while ensuring safety, the automatic system May be set when the cooling water flow rate (F1) of the phosgene reactor is reduced by 49% or more from the steady state, and may be set when the flow rate is further lowered by 54% or more from the steady state. .
<条件(ii)>
 条件(ii)は、ホスゲン反応器冷却水出口温度(T1)が定常時から5℃以上上昇した場合である。
 ホスゲン反応器には所定量の一酸化炭素及び塩素が連続的に供給されるが、ホスゲン生成反応は発熱反応であるため、ホスゲン反応器を冷却する必要がある。生産量、反応条件、冷却水温度等が定常時から変わってないにもかかわらずホスゲン化反応の異常により冷却水出口温度が上昇すると、ホスゲン反応器内温度が上昇し、それにより副生成物である四塩化炭素が多量に生成し、該四塩化炭素がポリカーボネート製品中に混入するため望ましくない。また、ホスゲン反応器内で反応温度が制御不能の状態となると、局所的にホスゲン反応器が高温となり、ホスゲン反応器が破損して、系外にホスゲンが漏洩する危険がある。
 そのため、本発明では、安全上の観点から、ホスゲン反応器冷却水出口温度(T1)が定常時から5℃以上上昇した場合に自動システムを起動させる。ただし、一過性のトラブル等により頻繁に自動システムが起動してしまうと、効率よく操業することが難しくなってしまうため、安全性を確保した上で効率よく操業するという観点からは、自動システムが起動する条件は、ホスゲン反応器冷却水出口温度(T1)が、定常時から10℃以上上昇した場合に設定してもよく、更に定常時から25℃以上上昇した場合に設定してもよい。
<Condition (ii)>
Condition (ii) is a case where the phosgene reactor cooling water outlet temperature (T1) is increased by 5 ° C. or more from the steady state.
A predetermined amount of carbon monoxide and chlorine are continuously supplied to the phosgene reactor. However, since the phosgene production reaction is an exothermic reaction, it is necessary to cool the phosgene reactor. If the cooling water outlet temperature rises due to abnormal phosgenation reaction even though the production volume, reaction conditions, cooling water temperature, etc. have not changed from the steady state, the temperature inside the phosgene reactor rises, and as a result, A certain amount of carbon tetrachloride is formed and is undesirable because the carbon tetrachloride is mixed into the polycarbonate product. Further, when the reaction temperature becomes uncontrollable in the phosgene reactor, the phosgene reactor becomes locally hot, the phosgene reactor is damaged, and there is a risk that phosgene leaks out of the system.
Therefore, in the present invention, from the viewpoint of safety, the automatic system is started when the phosgene reactor cooling water outlet temperature (T1) rises by 5 ° C. or more from the steady state. However, if the automatic system is frequently started due to temporary troubles, etc., it will be difficult to operate efficiently. From the viewpoint of operating efficiently while ensuring safety, the automatic system May be set when the phosgene reactor cooling water outlet temperature (T1) rises by 10 ° C. or more from the steady state, and may further be set when the temperature rises by 25 ° C. or more from the steady state. .
 本発明のポリカーボネートオリゴマー連続製造の制御方法では、上記の条件(i)及び/又は(ii)を満たす場合に、下記(a)、(b)及び(c)の操作が自動的に行われ、有毒なホスゲンの漏洩を防止すると共に無害化する。
 (a)ホスゲンガスを連続的に製造する工程(1)における塩素及び一酸化炭素の供給を停止する。これは、系内におけるホスゲンガスの量を増加させないことを目的として、ホスゲンガスの製造を中止する操作である。
 (b)オリゴマー反応器へのホスゲンガスの供給を停止する。これは、一部のホスゲンがオリゴマー反応器内で消費されずに未反応のまま下流の工程に流れるおそれがあるため、ホスゲンの漏洩を防止するための操作である。
 (c)系内のホスゲンガスを含む有毒ガスを除害手段に移送して無害化する。これは、上記(a)及び(b)の操作によりホスゲンの増加及び漏洩を防止して系内に封じ込めることに加えて、より高い安全性の観点から系内のホスゲンガスを無害化する操作である。
In the method for controlling the continuous production of polycarbonate oligomer of the present invention, when the above conditions (i) and / or (ii) are satisfied, the following operations (a), (b) and (c) are automatically performed: Prevents toxic phosgene leakage and renders it harmless.
(A) The supply of chlorine and carbon monoxide in the step (1) for continuously producing phosgene gas is stopped. This is an operation of stopping the production of phosgene gas for the purpose of not increasing the amount of phosgene gas in the system.
(B) The supply of phosgene gas to the oligomer reactor is stopped. This is an operation for preventing leakage of phosgene because a part of phosgene may flow into a downstream process without being consumed in the oligomer reactor without being consumed.
(C) Toxic gas containing phosgene gas in the system is transferred to an abatement means and rendered harmless. This is an operation of detoxifying the phosgene gas in the system from the viewpoint of higher safety, in addition to preventing the increase and leakage of phosgene by the above operations (a) and (b) and confining it in the system. .
<除害手段>
 除害手段は、ホスゲンガスを含む有毒ガスを除害剤により無害化するための設備であり、公知のものを用いることができる。具体例としては、除害剤の散布設備、有毒ガスと除害剤とを接触させる吸収塔等が挙げられる。また、特開平6-319946号公報や特開2005-305414号公報等に記載された塔型の除害設備を用いることもできる。
<Disinfection means>
The detoxifying means is equipment for detoxifying toxic gas containing phosgene gas with a detoxifying agent, and a known one can be used. Specific examples include a spraying device for a pesticide, an absorption tower for bringing a toxic gas into contact with the pesticide, and the like. In addition, tower-type detoxification equipment described in JP-A-6-319946, JP-A-2005-305414 and the like can also be used.
 ホスゲンや塩素等の酸性ガスに対しては、除害剤としてアルカリ性物質が用いられる。除害剤として用いられるアルカリ性物質は、特に限定されないが、水酸化ナトリウム、水酸化カリウムが一般的に用いられる。また、通常これらは水溶液として用いられる。 For acidic gases such as phosgene and chlorine, alkaline substances are used as a detoxifying agent. The alkaline substance used as the detoxifying agent is not particularly limited, but sodium hydroxide and potassium hydroxide are generally used. These are usually used as an aqueous solution.
 除害手段が除害塔の場合、除害塔の構造は特に限定されないが、代表的な例として、除害剤を塔の上部からスプレー等でシャワー状に噴射し、下部から供給された有害ガスと接触させて除害するものが挙げられる。除害剤とガスとの接触効率を高めるために、除害剤の噴射口とガスの流入口との間にラシヒリング等の充填剤を充填してもよい。また、除害塔の本数は特に限定されず、除害処理ガス中の有毒ガス濃度が、環境基準等で規定された所定濃度以下となるように、好ましくは検出されないレベルにまで低減されるように設計される。 When the detoxification means is a detoxification tower, the structure of the detoxification tower is not particularly limited, but as a typical example, the detoxifying agent is sprayed from the top of the tower in the form of a shower, etc. There are those that are removed by contact with gas. In order to improve the contact efficiency between the detoxifying agent and the gas, a filler such as Raschig ring may be filled between the detoxifying agent injection port and the gas inflow port. The number of detoxification towers is not particularly limited, and the toxic gas concentration in the detoxification treatment gas is preferably reduced to a level that is not detected so that the concentration is less than or equal to a predetermined concentration defined by environmental standards. Designed to.
 除害手段は、有毒ガスの漏洩がなくても不測の事態に備え常時運転する。なお、オリゴマー反応器が設置された建物内の換気空気は、ブロア等で除害手段に送られて無害化した上で外部に放出される。 Detoxification means always operate in case of unforeseen circumstances even if no toxic gas leaks. In addition, the ventilation air in the building where the oligomer reactor is installed is sent to an abatement means by a blower or the like to be rendered harmless and then released to the outside.
 本発明の好ましい一実施態様について、図面を参照しながら説明する。図1は、本発明のポリカーボネートオリゴマー連続製造の制御方法の好ましい一実施態様の概略を示す工程図である。
 通常運転時は、ホスゲン製造原料の塩素及び一酸化炭素は調節弁を通してホスゲン反応器に供給され、ホスゲン反応器においてホスゲンガスが製造される。反応は発熱反応であるため、ホスゲン反応器は冷却水によって冷却される。
 未反応の一酸化炭素を含有するホスゲンガス(反応生成物)は、調節弁を通してオリゴマー反応器に導入される。オリゴマー反応器には、ホスゲンガスに加えて、二価フェノールのアルカリ水溶液(具体的には、例えばビスフェノールAの水酸化ナトリウム水溶液)及び有機溶媒(具体的には、例えば塩化メチレン)も導入され、これらの反応により、ポリカーボネートオリゴマーを含有するエマルション溶液が製造される。
 なお、塩素及び一酸化炭素の供給路に設けられた調節弁は、これらの流量を自動制御しており、ホスゲンガスのオリゴマー反応器への供給路に設けられた調節弁は、オリゴマー反応器に供給するホスゲンガスの供給圧力を制御している。
A preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a process diagram showing an outline of a preferred embodiment of the method for controlling the continuous production of polycarbonate oligomer of the present invention.
During normal operation, phosgene production raw material chlorine and carbon monoxide are supplied to the phosgene reactor through a control valve, and phosgene gas is produced in the phosgene reactor. Since the reaction is exothermic, the phosgene reactor is cooled by cooling water.
Phosgene gas (reaction product) containing unreacted carbon monoxide is introduced into the oligomer reactor through a control valve. In addition to phosgene gas, an alkaline aqueous solution of dihydric phenol (specifically, for example, a sodium hydroxide aqueous solution of bisphenol A) and an organic solvent (specifically, for example, methylene chloride) are also introduced into the oligomer reactor. By this reaction, an emulsion solution containing a polycarbonate oligomer is produced.
In addition, the control valve provided in the supply path of chlorine and carbon monoxide automatically controls these flow rates, and the control valve provided in the supply path to the oligomer reactor of phosgene gas supplies to the oligomer reactor. The supply pressure of phosgene gas is controlled.
 ホスゲン反応器の冷却水流量(F1)は、流量計を用いて常時監視され、ホスゲン反応器冷却水出口温度(T1)は、温度計を用いて常時監視されており、その値は自動制御装置に送られている(図中の点線の矢印)。
 異常事態が発生した場合、すなわち、ホスゲン反応器の冷却水流量(F1)及びホスゲン反応器冷却水出口温度(T1)について、上記の条件(i)及び/又は(ii)を満たす場合には、自動制御装置から、塩素及び一酸化炭素の供給路に設けられた調節弁、ホスゲンガスのオリゴマー反応器への供給路に設けられた調節弁、並びに除害装置への流路に設けられた調節弁に一斉に信号が送られる(図中の太い実線の矢印)。
 自動制御装置からの信号により、塩素及び一酸化炭素の供給路に設けられた調節弁が閉じられ、塩素及び一酸化炭素の供給が停止される。また、ホスゲンガスのオリゴマー反応器への供給路に設けられた調節弁が閉じられ、オリゴマー反応器へのホスゲンガスの供給が停止される。
 除害装置への流路に設けられた調節弁は、通常運転時には閉じられているが、自動制御装置からの信号により開けられ、系内のホスゲンガスを含む有毒ガスは除害装置に移送される。除害装置において、ホスゲンガスを含む有毒ガスは無害化される。
The cooling water flow rate (F1) of the phosgene reactor is constantly monitored using a flow meter, and the phosgene reactor cooling water outlet temperature (T1) is constantly monitored using a thermometer, and the value is an automatic control device. (Dotted arrow in the figure).
When an abnormal situation occurs, that is, when the above conditions (i) and / or (ii) are satisfied for the cooling water flow rate (F1) and the phosgene reactor cooling water outlet temperature (T1) of the phosgene reactor, A control valve provided in the supply path of chlorine and carbon monoxide from the automatic control device, a control valve provided in the supply path to the oligomer reactor of phosgene gas, and a control valve provided in the flow path to the detoxification device Signals are sent all at once (thick solid arrows in the figure).
The control valve provided in the supply path for chlorine and carbon monoxide is closed by a signal from the automatic control device, and the supply of chlorine and carbon monoxide is stopped. Moreover, the control valve provided in the supply path to the oligomer reactor of phosgene gas is closed, and the supply of phosgene gas to the oligomer reactor is stopped.
The control valve provided in the flow path to the abatement device is closed during normal operation, but is opened by a signal from the automatic control device, and toxic gas including phosgene gas in the system is transferred to the abatement device. . In the abatement apparatus, toxic gas including phosgene gas is rendered harmless.
 以上、本発明の好ましい一実施態様について図面を参照しながら説明したが、本発明はこれに限定されない。例えば、図1には示されていないが、調節弁の他に各流体供給停止用の遮断弁を設けてもよい。 The preferred embodiment of the present invention has been described above with reference to the drawings, but the present invention is not limited to this. For example, although not shown in FIG. 1, a shutoff valve for stopping fluid supply may be provided in addition to the control valve.
 以下に、実施例に基づいて本発明を更に具体的に説明するが、本発明はこれらの実施例により何ら制限されるものではない。 Hereinafter, the present invention will be more specifically described based on examples, but the present invention is not limited to these examples.
実施例1-1
(自動制御装置)
 図1に示すように、ホスゲン反応器の冷却水流量(F1)が定常時から25%以上低下した場合(条件(i))又はホスゲン反応器冷却水出口温度(T1)が定常時から5℃以上上昇した場合(条件(ii))に、塩素及び一酸化炭素の供給路に設けられた調節弁並びにホスゲンガスのオリゴマー反応器への供給路に設けられた調節弁を閉止し、かつ、除害装置への流路に設けられた調節弁を開放するように制御を行う自動制御装置を設計した。
Example 1-1
(Automatic control device)
As shown in FIG. 1, when the cooling water flow rate (F1) of the phosgene reactor is reduced by 25% or more from the steady state (condition (i)), or the phosgene reactor cooling water outlet temperature (T1) is 5 ° C. from the steady state. In the case of the above increase (condition (ii)), the control valve provided in the supply path for chlorine and carbon monoxide and the control valve provided in the supply path to the oligomer reactor for phosgene gas are closed and detoxified. An automatic control device was designed to perform control so as to open a control valve provided in the flow path to the device.
(除害装置)
 除害装置として、カスケード・ミニ・リング(CMR)(商品名、マツイマシン(株)製)を充填した塔径600mm、充填層高さ10mの除害塔を使用した。除害塔には、除害剤として濃度10質量%の水酸化ナトリウム水溶液を2m3/hで循環させた。水酸化ナトリウム水溶液は塔の上部から、有毒なガスは下部から供給した。
(Abatement equipment)
As the abatement apparatus, an abatement tower having a tower diameter of 600 mm and a packed bed height of 10 m packed with Cascade Mini Ring (CMR) (trade name, manufactured by Matsui Machine Co., Ltd.) was used. A sodium hydroxide aqueous solution having a concentration of 10% by mass was circulated at 2 m 3 / h as a detoxifying agent in the detoxifying tower. Sodium hydroxide aqueous solution was supplied from the top of the tower, and toxic gas was supplied from the bottom.
(ホスゲンの製造)
 ホスゲン反応器として、チューブ内に市販の粒状活性炭(直径1.2~1.4mmに粉砕した椰子殻活性炭)を充填したシェルアンドチューブ型反応器を使用した。
 ホスゲン反応器に一酸化炭素1.2kg/h、塩素2.8kg/hを供給し、ホスゲンガス3.9kg/hを製造した。ホスゲン反応器のシェル部には、90℃の水を80kg/hで通水して反応熱を除去した。このときの水の反応器出口温度は93℃であり、圧力は0.2MPaGであった。
(Manufacture of phosgene)
As the phosgene reactor, a shell and tube reactor in which a commercially available granular activated carbon (coconut shell activated carbon pulverized to a diameter of 1.2 to 1.4 mm) was filled in a tube was used.
Carbon monoxide 1.2 kg / h and chlorine 2.8 kg / h were supplied to the phosgene reactor to produce phosgene gas 3.9 kg / h. 90 ° C. water was passed through the shell portion of the phosgene reactor at 80 kg / h to remove reaction heat. At this time, the reactor outlet temperature of water was 93 ° C., and the pressure was 0.2 MPaG.
(ポリカーボネートオリゴマーの製造)
 オリゴマー反応器として、内径6mm、長さ30mの管型反応器を使用した。オリゴマー反応器は20℃の冷却槽に浸した。ホスゲンガスは、上流のホスゲン製造工程から連続的にオリゴマー反応器に供給し、オリゴマー反応器に供給するホスゲンガスの供給圧力は0.45MPaGに設定した。
 オリゴマー反応器に、ホスゲンガス3.9kg/h、濃度6質量%水酸化ナトリウム水溶液にビスフェノールA(BPA)を溶解して得られた濃度13.5質量%のBPA水酸化ナトリウム水溶液44kg/h、塩化メチレン22kg/h、分子量調節用の濃度25質量%のp-tert-ブチルフェノールの塩化メチレン溶液0.46kg/hを供給し、ポリカーボネートオリゴマー溶液を製造した。このとき、オリゴマー反応器内の入口圧力は0.20MPaGであった。
(Production of polycarbonate oligomer)
As the oligomer reactor, a tubular reactor having an inner diameter of 6 mm and a length of 30 m was used. The oligomer reactor was immersed in a cooling bath at 20 ° C. The phosgene gas was continuously supplied from the upstream phosgene production process to the oligomer reactor, and the supply pressure of the phosgene gas supplied to the oligomer reactor was set to 0.45 MPaG.
In the oligomer reactor, phosgene gas 3.9 kg / h, bisphenol A (BPA) dissolved in 6% strength by weight sodium hydroxide aqueous solution, obtained by dissolving 13.5% by weight BPA aqueous sodium hydroxide 44 kg / h, chloride A methylene chloride solution (0.46 kg / h) of p-tert-butylphenol having a concentration of 25% by mass for adjusting the molecular weight was supplied at a rate of 22 kg / h to prepare a polycarbonate oligomer solution. At this time, the inlet pressure in the oligomer reactor was 0.20 MPaG.
 ここで、ホスゲン反応器の冷却水流量(F1)を意図的に25%低下させて60kg/hとした。
 その結果、自動制御装置により、ホスゲン反応器への塩素及び一酸化炭素の供給が停止されるとともにオリゴマー反応器へのホスゲンガスの供給が停止され、また、ホスゲン反応器で生成したホスゲンガスは除害装置へ移送された。除害塔の出口から排出されたガスについて成分測定を行ったところ、ホスゲンは検出されず無害化されていた。また、ホスゲン反応器の異常な温度上昇もなかった。
Here, the cooling water flow rate (F1) of the phosgene reactor was intentionally reduced by 25% to 60 kg / h.
As a result, the automatic control device stops the supply of chlorine and carbon monoxide to the phosgene reactor and the supply of phosgene gas to the oligomer reactor, and the phosgene gas generated in the phosgene reactor is removed from the abatement device. It was transferred to. When components were measured for the gas discharged from the exit of the detoxification tower, phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
実施例1-2
 ホスゲン反応器の冷却水流量(F1)を意図的に50%低下させて40kg/hとしたこと以外は、実施例1-1と同様にしてポリカーボネートオリゴマーの製造を行った。
 その結果、実施例1-1と同様に、自動制御装置により、ホスゲン反応器への塩素及び一酸化炭素の供給が停止されるとともにオリゴマー反応器へのホスゲンガスの供給が停止され、また、ホスゲン反応器で生成したホスゲンガスは除害装置へ移送された。除害塔の出口から排出されたガスについて成分測定を行ったところ、ホスゲンは検出されず無害化されていた。また、ホスゲン反応器の異常な温度上昇もなかった。
Example 1-2
A polycarbonate oligomer was produced in the same manner as in Example 1-1 except that the cooling water flow rate (F1) of the phosgene reactor was intentionally reduced by 50% to 40 kg / h.
As a result, as in Example 1-1, the supply of chlorine and carbon monoxide to the phosgene reactor was stopped and the supply of phosgene gas to the oligomer reactor was stopped by the automatic controller, and the phosgene reaction The phosgene gas generated in the vessel was transferred to the abatement device. When components were measured for the gas discharged from the exit of the detoxification tower, phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
実施例1-3
 ホスゲン反応器の冷却水流量(F1)を意図的に55%低下させて36kg/hとしたこと以外は、実施例1-1と同様にしてポリカーボネートオリゴマーの製造を行った。
 その結果、実施例1-1と同様に、自動制御装置により、ホスゲン反応器への塩素及び一酸化炭素の供給が停止されるとともにオリゴマー反応器へのホスゲンガスの供給が停止され、また、ホスゲン反応器で生成したホスゲンガスは除害装置へ移送された。除害塔の出口から排出されたガスについて成分測定を行ったところ、ホスゲンは検出されず無害化されていた。また、ホスゲン反応器の異常な温度上昇もなかった。
Example 1-3
A polycarbonate oligomer was produced in the same manner as in Example 1-1 except that the cooling water flow rate (F1) of the phosgene reactor was intentionally reduced by 55% to 36 kg / h.
As a result, as in Example 1-1, the supply of chlorine and carbon monoxide to the phosgene reactor was stopped and the supply of phosgene gas to the oligomer reactor was stopped by the automatic controller, and the phosgene reaction The phosgene gas generated in the vessel was transferred to the abatement device. When components were measured for the gas discharged from the exit of the detoxification tower, phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
比較例1-1
 自動制御装置を使用しなかったこと以外は、実施例1-1と同様にしてポリカーボネートオリゴマーの製造を行おうとした。
 しかし、自動制御しなかった場合、ホスゲン反応器内で局所的な温度上昇が予想され、操作を続けると、ホスゲン反応器内温度が局所的に設計温度以上となり、ホスゲン反応器が破損してホスゲンが系外に漏洩することが想定されたため、この操作を中止した。
Comparative Example 1-1
A polycarbonate oligomer was produced in the same manner as in Example 1-1 except that the automatic controller was not used.
However, if automatic control is not performed, a local temperature rise is expected in the phosgene reactor, and if the operation is continued, the temperature inside the phosgene reactor locally exceeds the design temperature, and the phosgene reactor is damaged and the phosgene reactor is damaged. This operation was stopped because it was assumed that would leak out of the system.
実施例2-1
 ホスゲン反応器冷却水出口温度(T1)を意図的に5℃上昇させたこと以外は、実施例1-1と同様にしてポリカーボネートオリゴマーの製造を行った。
 その結果、実施例1-1と同様に、自動制御装置により、ホスゲン反応器への塩素及び一酸化炭素の供給が停止されるとともにオリゴマー反応器へのホスゲンガスの供給が停止され、また、ホスゲン反応器で生成したホスゲンガスは除害装置へ移送された。除害塔の出口から排出されたガスについて成分測定を行ったところ、ホスゲンは検出されず無害化されていた。また、ホスゲン反応器の異常な温度上昇もなかった。
Example 2-1
A polycarbonate oligomer was produced in the same manner as in Example 1-1 except that the phosgene reactor cooling water outlet temperature (T1) was intentionally increased by 5 ° C.
As a result, as in Example 1-1, the supply of chlorine and carbon monoxide to the phosgene reactor was stopped and the supply of phosgene gas to the oligomer reactor was stopped by the automatic controller, and the phosgene reaction The phosgene gas generated in the vessel was transferred to the abatement device. When components were measured for the gas discharged from the exit of the detoxification tower, phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
実施例2-2
 ホスゲン反応器冷却水出口温度(T1)を意図的に10℃上昇させたこと以外は、実施例2-1と同様にしてポリカーボネートオリゴマーの製造を行った。
 その結果、実施例2-1と同様に、自動制御装置により、ホスゲン反応器への塩素及び一酸化炭素の供給が停止されるとともにオリゴマー反応器へのホスゲンガスの供給が停止され、また、ホスゲン反応器で生成したホスゲンガスは除害装置へ移送された。除害塔の出口から排出されたガスについて成分測定を行ったところ、ホスゲンは検出されず無害化されていた。また、ホスゲン反応器の異常な温度上昇もなかった。
Example 2-2
A polycarbonate oligomer was produced in the same manner as in Example 2-1, except that the phosgene reactor cooling water outlet temperature (T1) was intentionally increased by 10 ° C.
As a result, as in Example 2-1, the automatic control device stopped the supply of chlorine and carbon monoxide to the phosgene reactor and the supply of phosgene gas to the oligomer reactor, and the phosgene reaction The phosgene gas generated in the vessel was transferred to the abatement device. When components were measured for the gas discharged from the exit of the detoxification tower, phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
実施例2-3
 ホスゲン反応器冷却水出口温度(T1)を意図的に25℃上昇させたこと以外は、実施例2-1と同様にしてポリカーボネートオリゴマーの製造を行った。
 その結果、実施例2-1と同様に、自動制御装置により、ホスゲン反応器への塩素及び一酸化炭素の供給が停止されるとともにオリゴマー反応器へのホスゲンガスの供給が停止され、また、ホスゲン反応器で生成したホスゲンガスは除害装置へ移送された。除害塔の出口から排出されたガスについて成分測定を行ったところ、ホスゲンは検出されず無害化されていた。また、ホスゲン反応器の異常な温度上昇もなかった。
Example 2-3
A polycarbonate oligomer was produced in the same manner as in Example 2-1, except that the phosgene reactor cooling water outlet temperature (T1) was intentionally increased by 25 ° C.
As a result, as in Example 2-1, the automatic control device stopped the supply of chlorine and carbon monoxide to the phosgene reactor and the supply of phosgene gas to the oligomer reactor, and the phosgene reaction The phosgene gas generated in the vessel was transferred to the abatement device. When components were measured for the gas discharged from the exit of the detoxification tower, phosgene was not detected and was rendered harmless. There was also no abnormal temperature rise in the phosgene reactor.
比較例2-1
 自動制御装置を使用しなかったこと以外は、実施例2-1と同様にしてポリカーボネートオリゴマーの製造を行おうとした。
 しかし、自動制御しなかった場合、ホスゲン反応器内で局所的な温度上昇が予想され、操作を続けると、ホスゲン反応器内温度が局所的に設計温度以上となり、ホスゲン反応器が破損してホスゲンが系外に漏洩することが想定されたため、この操作を中止した。
Comparative Example 2-1
A polycarbonate oligomer was produced in the same manner as in Example 2-1, except that the automatic controller was not used.
However, if automatic control is not performed, a local temperature rise is expected in the phosgene reactor, and if the operation is continued, the temperature inside the phosgene reactor locally exceeds the design temperature, and the phosgene reactor is damaged and the phosgene reactor is damaged. This operation was stopped because it was assumed that would leak out of the system.
 本発明の方法によれば、安全にポリカーボネートオリゴマーを連続的に製造することができる。特に、ホスゲン反応器破損につながる反応器の冷却トラブル等の事故が起きた場合でも、自動制御により、ホスゲンの製造及び供給を緊急停止すると共に、系内のホスゲンガスを含む有毒ガスを無害化し、有毒ガスが系外に漏洩することがない。 According to the method of the present invention, a polycarbonate oligomer can be continuously produced safely. In particular, even if an accident such as a reactor cooling problem that leads to damage to the phosgene reactor occurs, the automatic control automatically stops the production and supply of phosgene and renders toxic gases including phosgene gas harmless. No poison gas leaks out of the system.

Claims (2)

  1.  塩素及び一酸化炭素をホスゲン反応器に供給し未反応の一酸化炭素を含有するホスゲンガスを連続的に製造する工程(1)、並びに前記工程(1)で連続的に製造されたホスゲンガス、二価フェノールのアルカリ水溶液及び有機溶媒をオリゴマー反応器に連続的に供給して、ポリカーボネートオリゴマーを含有する反応混合物を連続的に製造する工程(2)を含むポリカーボネートオリゴマー連続製造の制御方法であって、
     下記の条件(i)及び/又は(ii)を満たす場合に、前記工程(1)における塩素及び一酸化炭素の供給を停止すると共に、オリゴマー反応器へのホスゲンガスの供給を停止させ、かつ、ホスゲンガスを含む有毒ガスを除害手段に移送して無害化する、ポリカーボネートオリゴマー連続製造の制御方法。
     条件(i):ホスゲン反応器の冷却水流量(F1)が定常時から25%以上低下した場合。
     条件(ii):ホスゲン反応器冷却水出口温度(T1)が定常時から5℃以上上昇した場合。
    Step (1) for continuously producing phosgene gas containing unreacted carbon monoxide by supplying chlorine and carbon monoxide to the phosgene reactor, and phosgene gas continuously produced in step (1), divalent A method for controlling polycarbonate oligomer continuous production comprising the step (2) of continuously producing a reaction mixture containing a polycarbonate oligomer by continuously supplying an alkaline aqueous solution of phenol and an organic solvent to an oligomer reactor,
    When the following conditions (i) and / or (ii) are satisfied, the supply of chlorine and carbon monoxide in the step (1) is stopped, the supply of phosgene gas to the oligomer reactor is stopped, and the phosgene gas A control method for continuous production of polycarbonate oligomers, wherein a toxic gas containing is transferred to a detoxifying means and rendered harmless.
    Condition (i): The cooling water flow rate (F1) of the phosgene reactor is reduced by 25% or more from the steady state.
    Condition (ii): The phosgene reactor cooling water outlet temperature (T1) rises by 5 ° C. or more from the steady state.
  2.  前記除害手段が、ホスゲンガスを含む有毒ガスをアルカリ水溶液と接触させて無害化する手段である、請求項1に記載のポリカーボネートオリゴマー連続製造の制御方法。 The method for controlling the continuous production of polycarbonate oligomer according to claim 1, wherein the detoxifying means is a means for detoxifying the toxic gas containing phosgene gas by contacting with an alkaline aqueous solution.
PCT/JP2011/064829 2011-03-31 2011-06-28 Control method for safe continuous manufacturing of polycarbonate oligomer WO2012132031A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020137025131A KR101823724B1 (en) 2011-03-31 2011-06-28 Control method for safe continuous manufacturing of polycarbonate oligomer

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2011-080976 2011-03-31
JP2011080976A JP5775347B2 (en) 2011-03-31 2011-03-31 Control method for continuous production of polycarbonate oligomer

Publications (1)

Publication Number Publication Date
WO2012132031A1 true WO2012132031A1 (en) 2012-10-04

Family

ID=45332914

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2011/064829 WO2012132031A1 (en) 2011-03-31 2011-06-28 Control method for safe continuous manufacturing of polycarbonate oligomer

Country Status (5)

Country Link
JP (1) JP5775347B2 (en)
KR (1) KR101823724B1 (en)
CN (1) CN102286144B (en)
TW (1) TWI501992B (en)
WO (1) WO2012132031A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022248501A1 (en) * 2021-05-27 2022-12-01 Basf Se Method for producing phosgene

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101842501B1 (en) * 2014-08-20 2018-03-27 바이엘 악티엔게젤샤프트 Method for phosgenation of compounds comprising hydroxyl, thiol, amino and/or formamide groups
JP6357408B2 (en) * 2014-11-07 2018-07-11 出光興産株式会社 Method for producing branched polycarbonate

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002528367A (en) * 1998-10-22 2002-09-03 バイエル アクチェンゲゼルシャフト Phosgene with low carbon tetrachloride content
WO2007083721A1 (en) * 2006-01-17 2007-07-26 Teijin Chemicals Ltd. Process for continuous production of polycarbonate oligomer

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06319946A (en) * 1993-05-18 1994-11-22 Mitsui Toatsu Chem Inc Method for removing toxic gas in toxicity-removing tower
JP2002080578A (en) * 2000-09-05 2002-03-19 Idemitsu Petrochem Co Ltd Method for manufacturing polycarbonate
CN1281655C (en) * 2001-09-27 2006-10-25 出光兴产株式会社 Polycarbonate resin and method for producing same
DE102004041777A1 (en) * 2004-08-28 2006-03-02 Bayer Materialscience Ag Process and apparatus for the production of phosgene
US7132498B2 (en) * 2004-09-27 2006-11-07 General Electric Company Process to make polycarbonate from bismethylsalicylcarbonate (BMSC)
JP2006137669A (en) * 2005-12-05 2006-06-01 Sumitomo Chemical Co Ltd Method for producing phosgene
JP5235082B2 (en) * 2008-02-25 2013-07-10 日本曹達株式会社 Chlorination method and detection method of reaction end point
JP2009280725A (en) * 2008-05-23 2009-12-03 Idemitsu Kosan Co Ltd Flame-retardant polycarbonate resin composition and light reflection member

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002528367A (en) * 1998-10-22 2002-09-03 バイエル アクチェンゲゼルシャフト Phosgene with low carbon tetrachloride content
WO2007083721A1 (en) * 2006-01-17 2007-07-26 Teijin Chemicals Ltd. Process for continuous production of polycarbonate oligomer

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022248501A1 (en) * 2021-05-27 2022-12-01 Basf Se Method for producing phosgene

Also Published As

Publication number Publication date
CN102286144B (en) 2013-04-10
KR20140009405A (en) 2014-01-22
TWI501992B (en) 2015-10-01
CN102286144A (en) 2011-12-21
KR101823724B1 (en) 2018-01-30
JP2012214633A (en) 2012-11-08
TW201239001A (en) 2012-10-01
JP5775347B2 (en) 2015-09-09

Similar Documents

Publication Publication Date Title
JP5775347B2 (en) Control method for continuous production of polycarbonate oligomer
JP2007533805A5 (en)
ZA200601416B (en) Method for producing polycarbonate
JP5795975B2 (en) Continuous production method of polycarbonate
JPWO2007083721A1 (en) Continuous production method of polycarbonate oligomer
JP5775346B2 (en) Control method for continuous production of polycarbonate oligomer
JP5775345B2 (en) Control method for continuous production of polycarbonate oligomer
JP4624055B2 (en) Method for producing alkylene carbonate
JP2020525515A (en) Manufacturing facility for reacting H-functional reactants with phosgene to produce chemical products and method of operating same
JP2009138102A (en) Method for producing polycarbonate resin
JP2005008688A (en) Method for producing polycarbonate
JP2002080577A (en) Method and apparatus for manufacturing polycarbonate
JP2007321160A (en) Process for producing aromatic polycarbonate

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11862150

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 20137025131

Country of ref document: KR

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11862150

Country of ref document: EP

Kind code of ref document: A1