JP5278865B2 - Methyl iodide production apparatus, methyl iodide production method, and methyl triflate production apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for producing methyl iodide, effective for stabilizing the synthetic reaction and reducing the maintenance work, sufficiently improving the reliability and enabling the continuous synthesis of<SP>11</SP>CH<SB>3</SB>I, a method for producing methyl iodide and an apparatus for producing methyl triflate. <P>SOLUTION: The formation of impurities caused by the reaction of hydrogen gas with iodine gas is suppressed to reduce the clogging of a<SP>11</SP>CH<SB>3</SB>I synthesis column 11 by making<SP>11</SP>CH<SB>4</SB>temporarily adsorbed with a<SP>11</SP>CH<SB>4</SB>adsorption column at the former stage of a<SP>11</SP>CH<SB>3</SB>I synthesis system 4 and removing the unreacted hydrogen gas accompanying to<SP>11</SP>CH<SB>4</SB>. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  The present invention relates to a methyl iodide production apparatus, a methyl iodide production method, and a methyl triflate production apparatus.

Conventionally, ¹¹ CO ₂ and HI were introduced into LiAlH ₄ accommodated in a reactor together with an organic solvent tetrahydrofuran (THF) as a production apparatus for methyl iodide ( ¹¹ CH ₃ I), which is a radiopharmaceutical labeling precursor. Then, a reaction in a liquid phase to synthesize ¹¹ CH ₃ I is known (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 4-200552

In such a methyl iodide production apparatus that performs a synthesis reaction in the liquid phase, the liquid remains in the reactor, and it is necessary to wash or replace the reactor for each synthesis reaction. There is a risk that workers will be exposed during the process. Furthermore, since the reactor is small and complicated, handling is inconvenient, and LiAlH ₄ and HI are dangerous because they are powerful drugs. In order to prevent such a problem, as shown in FIG. ^4, to generate a to ¹¹ CH ₄ introduced a 11 CO ₂ and hydrogen gas _{H 2} to ¹¹ CH ₄ conversion column 6, this ¹¹ CH ₄ It is known that iodine gas is introduced into the reactor 11 and reacted to synthesize ¹¹ CH ₃ I in the gas phase.

However, in such a methyl iodide production apparatus that performs a synthesis reaction in the gas phase, impurities in the apparatus may be clogged in the reactor, and the synthesis reaction of ¹¹ CH ₃ I may become unstable. There is a problem that a continuous synthesis of ¹¹ CH ₃ I cannot be performed due to maintenance work such as washing and replacement of the reactor.

The present invention has been made to solve such problems. The present invention aims to stabilize the synthesis reaction and reduce maintenance work, to sufficiently improve the reliability and to continuously synthesize ¹¹ CH ₃ I. An object is to provide a methyl iodide production apparatus, a methyl iodide production method, and a methyl triflate production apparatus.

As a result of intensive studies to achieve the above object, the present inventors have introduced unreacted hydrogen gas accompanying ¹¹ CH ₄ into the reactor, and the hydrogen gas reacts with iodine gas. It has been found that the generation of impurities due to the above causes clogging in the reactor.

Therefore, methyl iodide manufacturing apparatus according to the present invention ^{generates 11} CH ₄ by using a raw material gas and hydrogen gas containing 11 CO ^_2, to synthesize a ¹¹ CH ₃ I by using the 11 CH ₄ and iodine gas a methyl iodide manufacturing apparatus, and ¹¹ CO ₂ adsorption column in which the first adsorbent is filled to the ¹¹ CO ₂ contained in the raw material gas is temporarily adsorbed to separate the ¹¹ CO ₂ from the raw material ^{gas, 11} and ¹¹ CH ₄ conversion columns reduction catalyst is filled to convert the ¹¹ CO ₂ with provided downstream of the CO ₂ adsorption column by the hydrogen gas to ¹¹ CH ^{_4, 11} together is provided after the 11 CH ₄ conversion column CH ₄ ¹¹ CH ₄ purification column a second adsorbent to separate the ¹¹ CO ₂ unreacted ¹¹ CO ₂ unreacted from ¹¹ CH ₄ is adsorbed filled entrained into the And ¹¹ CH ₄ production system ^with, 11 CH ₄ provided after the generating system ^has a ¹¹ CH ₄ adsorption columns third adsorbent is filled to temporarily adsorb 11 CH _^4, 11 CH ₄ ¹¹ CH ₄ adsorption system that removes unreacted hydrogen gas accompanying the gas, and ¹¹ CH ₄ adsorption system that is provided in the subsequent stage, and synthesizes ¹¹ CH ₄ and iodine gas to synthesize ¹¹ CH ₃ I ¹¹ CH _And an ¹¹ CH ₃ I synthesis system having a ₃ I synthesis column .

In addition, in the method for producing methyl iodide according to the present invention, ¹¹ CO ₂ is temporarily adsorbed on an ¹¹ CO ₂ adsorption column packed with a _first adsorbent that temporarily adsorbs ¹¹ CO ₂ , and the raw material gas is used. ¹¹ CO ₂ adsorption step for separating ¹¹ CO ₂ and ¹¹ CO ₂ adsorption step, ¹¹ CO ₂ is converted into ¹¹ CH ₄ with hydrogen gas , and then a _second adsorbent that adsorbs ¹¹ CO ₂ is filled. and ¹¹ CH ₄ and ¹¹ CH ₄ production step of separating the ¹¹ CO ₂ unreacted purification column ¹¹ CO ₂ accompanying the ¹¹ CH ₄ from ¹¹ CH ₄ ^adsorbed, after 11 CH ₄ production ^step, 11 CH the third adsorbent for ₄ temporarily adsorbs to remove the unreacted hydrogen gas accompanying the ¹¹ CH ₄ temporarily adsorbing the ¹¹ CH ₄ to ¹¹ CH ₄ adsorption column filled ¹ And CH ₄ adsorption ^step, after 11 CH ₄ adsorption ^step, is characterized in that it comprises a a ¹¹ CH ₃ I synthesis process of synthesizing the ¹¹ CH ₃ I by combining reaction of the iodine gas 11 CH ₄ .

Further, methyl triflate manufacturing apparatus according to the present ^invention, the ¹¹ CH ₄ produced using a raw material gas and hydrogen gas containing 11 CO ^_2, to synthesize a ¹¹ CH ₃ I by using the 11 CH ₄ and iodine gas , A methyl triflate production apparatus for synthesizing ¹¹ CH ₃ OTf using ¹¹ CH ₃ I, wherein the ¹¹ CO ₂ contained in the source gas is temporarily adsorbed to separate ¹¹ CO ₂ from the source gas . and ¹¹ CO ₂ adsorption column adsorbent is filled ^in, and ¹¹ CH ₄ conversion columns reduction catalyst is filled to convert the ¹¹ CO ₂ with is provided after the 11 CO ₂ adsorption column by the hydrogen gas to ¹¹ CH ₄ , ¹¹ CH ₄ and ¹¹ CO ₂ unreacted accompanying the ¹¹ CH ₄ with are provided after the conversion columns from ¹¹ CH ₄ is adsorbed unreacted ¹¹ CO ¹¹ and CH ₄ purification column the second adsorbent is filled to separate, and ¹¹ CH ₄ production system with ^a 11 CH ₄ provided after the generation ^system, the third to temporarily adsorb 11 CH ₄ has a ¹¹ CH ₄ adsorption column adsorbent is filled ^in, 11 and ¹¹ CH ₄ adsorption system to remove unreacted hydrogen gas accompanying the CH _^4, provided after the 11 CH ₄ adsorption ^system, 11 CH ₄ and the ¹¹ CH ₃ I synthesis system with ¹¹ CH ₃ I synthesis column for synthesizing ¹¹ CH ₃ I by the iodine gas is synthesis ^reaction, provided after the 11 CH ₃ I synthesis ^system, the 11 CH ₃ I used are the ¹¹ CH ₃ OTf synthesis system with ¹¹ CH ₃ OTf synthesis column for synthesizing ¹¹ CH ₃ OTf, characterized in that it comprises.

According to the methyl iodide manufacturing apparatus, methyl iodide manufacturing method, and methyl triflate manufacturing apparatus configured as described above, ¹¹ CH ₄ is temporarily adsorbed to ¹¹ CH ₄ before the synthesis of ¹¹ CH ₃ I. Since the accompanying unreacted hydrogen gas is removed, the generation of impurities due to the reaction between the hydrogen gas and iodine gas is suppressed, and clogging in the reactor is reduced.

Here, if the ¹¹ CH ₄ adsorption system has a purge path for supplying a purge fluid, the inside of the ¹¹ CH ₄ adsorption system is purged, and unreacted hydrogen gas is suitably discharged out of the system.

^Further, 11 CH ₄ when generating system is a configuration with ¹¹ CO ₂ adsorption chamber for concentrating ¹¹ CO ₂ temporarily adsorbing the ¹¹ CO ₂ contained in the raw material gas, the amount of gas flowing in the device is reduced As a result, the reaction efficiency is increased and the power for gas transfer is reduced.

^Further, a path 11 CH ₃ comprises a ¹¹ CH ₃ OTf ¹¹ CH ₃ OTf synthesis system for synthesizing a (methyl triflate) using subsequent to ¹¹ CH ₃ I of I synthesis ^system, to recover the 11 CH ₃ ^{I, 11} It may be configured to have a switching means for selectively switching the route for collecting ¹¹ CH ₃ OTf by supplying CH ₃ I to the ¹¹ CH ₃ OTf synthesis system.

As described above, according to the methyl iodide production apparatus and the methyl iodide production method according to the present invention, since the generation of impurities due to the reaction between hydrogen gas and iodine gas is suppressed and clogging in the reactor is reduced, Methyl iodide production apparatus and iodide capable of stabilizing the synthesis reaction and greatly reducing maintenance work such as washing and replacement of the reactor, sufficiently improving the reliability and enabling continuous synthesis of ¹¹ CH ₃ I It is possible to provide a method for producing methyl.

As described above, according to the apparatus for producing methyl triflate according to the present invention, since the generation of impurities due to the reaction between hydrogen gas and iodine gas is suppressed and clogging in the reactor is reduced, the synthesis reaction is stabilized. At the same time, maintenance work such as cleaning and replacement of the reactor is greatly reduced, and it is possible to provide a methyl triflate production apparatus capable of improving the reliability sufficiently and continuously synthesizing ¹¹ CH ₃ OTf.

  Hereinafter, a preferred embodiment of a methyl iodide production apparatus according to the present invention will be described with reference to FIGS. FIG. 1 is a schematic configuration diagram showing a methyl iodide manufacturing apparatus according to an embodiment of the present invention, and FIG. 2 is a schematic configuration diagram showing a methyl iodide manufacturing apparatus when the six-way valve in FIG. 1 is in a first state. FIG. 3 is a schematic configuration diagram showing an apparatus for producing methyl iodide when the six-way valve in FIG. 1 is in the second state. In the description of the drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted.

As shown in FIG. 1, the methyl iodide production apparatus 1 of the present embodiment includes ¹¹ CH ₃ I, which is a radiopharmaceutical label precursor used in, for example, a PET examination (positron emission tomography examination) in a hospital or the like. This is an apparatus for producing methyl iodide.

The methyl iodide manufacturing apparatus 1 is a schematic, the ¹¹ CH ₄ generation system 2 for converting to the ¹¹ CH ₄ reduced by the outside of the system of the cyclotron hydrogen gas ¹¹ CO ₂ which is supplied from a (not shown), the ¹¹ CH ₄ ¹¹ CH ₄ adsorption system 3 for temporarily adsorbing and ¹¹ CH ₃ I synthesis system 4 for synthesizing ¹¹ CH ₃ I by reacting ¹¹ CH ₄ with iodine gas.

^{The 11} CH ₄ generation system 2 includes a source gas supply pipe L1 for supplying a source gas containing ¹¹ CO ₂ in the system, a hydrogen gas supply pipe L2 for supplying a carrier gas containing hydrogen gas in the system, and these pipes L1, Three-way valve V1 that collects L2 and selects and switches one pipe, ¹¹ CO ₂ adsorption column (adsorption chamber) 5 that temporarily adsorbs ¹¹ CO ₂ in the raw material gas, and is temporarily adsorbed by this ¹¹ CO ₂ adsorption column 5 and ¹¹ CO ₂ and ¹¹ CH ₄ ¹¹ is converted to CH ₄ conversion column 6, the ¹¹ CH ₄ conversion column ¹¹ is converted by the 6 CH ₄ purifying ¹¹ CH ₄ purification column 7, these three-way valves ^V1, 11 CO are provided with ₂ adsorption column ^5, 11 CH ₄ conversion columns 6 and ¹¹ CH ₄ ¹¹ in the subsequent stage by connecting the purification column 7 in this order CH ₄ pipe L3 connected to the suction system 3

^{The 11} CO ₂ adsorption column 5 is filled with an adsorbent such as Cabosphere (registered trademark) that temporarily adsorbs ¹¹ CO ₂ inside, and is heated and cooled to heat and cool the ¹¹ CO ₂ adsorption column 5 outside. The apparatus and an RI monitor 16 for measuring the radioactivity of the ¹¹ CO ₂ adsorption column 5 are provided. Adsorbent for temporarily adsorbing ¹¹ CO ₂ adsorbs ambient temperature with ¹¹ CO _2, in which desorbs ¹¹ CO ₂ is heated.

^{The 11} CH ₄ conversion column 6 is filled inside with a reduction catalyst such as Shimalite Ni (registered trademark) that converts ¹¹ CO ₂ into ¹¹ CH ₄ with hydrogen gas, and the ¹¹ CH ₄ conversion column 6 is provided outside. A heating device for heating is provided.

^{The 11} CH ₄ purification column 7 is filled with an adsorbent such as Ascarite II (registered trademark), soda lime (Soda Lime) or the like that adsorbs unconverted ¹¹ CO ₂ or the like.

¹¹ CH ₄ adsorption system in the subsequent stage of the ¹¹ CH ₄ generation system 2 3, a plurality of connection ports a~f can be selected two types of connection status has a ¹¹ CH ₄ connected to the purification column 7 is hexagonal valve V2, the hexagonal valve is connected to V2 ¹¹ CH ₄ ¹¹ to temporarily adsorb the CH ₄ adsorption column 8, edge cutting valves He supply pipe for supplying He gas into the system with a V6 (purge path) L6, provided with edge cutting valve V7 An exhaust pipe L10 for discharging exhaust gas in the system to the outside of the system, and a three-way valve V3 connected to the exhaust pipe L10 via a pipe L9, and ¹¹ CH ₄ in the system is connected to the subsequent ¹¹ CH ₃ I synthesis system 4 is provided.

The six-way valve V2 is provided with six connection ports a to f, the connection port a is an outlet of the ¹¹ CH ₄ purification column 7 via the pipe L3, and the connection port b is an ¹¹ CH ₄ adsorption column via the pipe L4. 8, the inlet c is a He supply pipe L6, the connection d is an exhaust pipe L10 through a pipe L7, and the connection e is an outlet of the ¹¹ CH ₄ adsorption column 8 through a pipe L5. The connection port f is connected to the three-way valve V3 via a pipe L8.

  In addition, the six-way valve V2 can be selected in either the first state or the second state. In the first state, as shown in FIG. 2, the connection port a and the connection port f are connected to each other. The port e and the connection port d communicate with each other, and the connection port c and the connection port b communicate with each other. In the second state, as shown in FIG. 3, the connection port a and the connection port b are connected to each other. d is connected to the connection port e and the connection port f.

^{The 11} CH ₄ adsorption column 8 is filled with an adsorbent such as Cabosphere (registered trademark) that temporarily adsorbs ¹¹ CH ₄ inside, and the outside is heated / cooled by heating / cooling the ¹¹ CH ₄ adsorption column 8. An RI monitor 17 for measuring radioactivity of the cooling device and the ¹¹ CH ₄ adsorption column 8 is provided.

Subsequent ¹¹ CH ₃ I synthesis system 4 of the ¹¹ CH ₄ adsorption system 3, a three-way valve connected to the pipe L11 ^V4, 11 CH ₄ to iodine column 10 for mixing iodine gas was mixed with the iodine column 10 ¹¹ CH ₄ and ¹¹ CH ₃ I synthesis column ^(reactor) for synthesis reaction of iodine gas ^{11, 11} CH ₃ I to purify the ¹¹ CH ₃ I purification column ^{12, 11} CH ₃ 11 to temporarily adsorb I CH ₃ I Adsorption column 13, these three-way valve V4, iodine column 10, ¹¹ CH ₃ I synthesis column 11, pipe ¹¹ connecting ¹¹ CH ₃ I purification column 12 in this order, three-way valve V5 connected to this pipe L12, three-way valve V5, V4 circulation pipe L13 connecting the circulation pump 19 installed in the circulation pipe L13, was synthesized and is connected to the three-way valve V5 And comprising a product pipe L14 for transferring ¹ CH ₃ I.

  The iodine column 10 is filled with solid iodine inside, and includes a heating device that heats the iodine column 10 outside.

^{The 11} CH ₃ I synthesis column 11 is made of, for example, a glass material, and includes a heating device that heats the ¹¹ CH ₃ I synthesis column.

^{The 11} CH ₃ I purification column 12 is filled with an adsorbent such as Ascarite II (registered trademark) that adsorbs unreacted ¹¹ CO ₂ and impurities.

¹¹ CH ₃ I adsorption column 13, the ^inner, 11 CH ₃ adsorbent such Porapak N to temporarily adsorb I is filled, the outside, the ¹¹ CH ₃ I heating and cooling device for heating and cooling the adsorption column 13 ¹¹ equipped with an RI monitor 18 for measuring the radioactivity from the CH ₃ I adsorption column 13. Adsorbent for temporarily adsorbing the ¹¹ CH ₃ I adsorbs ambient temperature at ¹¹ CH ₃ I, in which desorbs heated to ¹¹ CH ₃ I.

Further, methyl iodide manufacturing apparatus ^1, 11 downstream of the CH ₃ I synthesis system, the synthesized ¹¹ CH ₃ with I ¹¹ CH ₃ OTf synthesizing (labeled precursors) ¹¹ CH ₃ OTf synthesis column 15 ¹¹ CH ₃ OTf synthesis system 14 provided.

^{The 11} CH ₃ OTf synthesis column 15 is filled with AgOTf inside, and has an external heating device for heating the ¹¹ CH ₃ OTf synthesis column 15, and its inlet is installed in the product pipe L 14 via the pipe L 17. Connected to the three-way valve V10, and the outlet thereof is connected to the three-way valve V11 installed in the product pipe L14 via the pipe L18. These three-way valve V10, V11 ^is a product pipe L14 to recover 11 CH ₃ ^I, and a 11 CH ₃ I to ¹¹ CH ₃ OTf synthesis system 14 pipe that recovers the supplied with ¹¹ CH ₃ OTf to L17, L18 Switching means for selectively switching.

Next, a methyl iodide manufacturing method for synthesizing ¹¹ CH ₃ I using the thus configured methyl iodide manufacturing apparatus 1 will be described with reference to the drawings. The methyl iodide manufacturing method is a schematic, a ¹¹ CO ₂ adsorption step of concentrating the ¹¹ CO ₂ in the raw material gas, and ¹¹ CH ₄ generation step of generating a ¹¹ CH ₄ by using the ¹¹ CO ^_2, the 11 CH ₄ and ¹¹ CH ₄ adsorption step of separating and removing hydrogen gas and the like of unreacted by temporarily adsorbed, and ¹¹ CH ₃ I synthesis process of synthesizing the ¹¹ CH ₄ and iodine by synthesis ¹¹ CH ₃ I, the In order.

^{In the 11} CO ₂ adsorption step, the raw material gas supplied from a cyclotron (not shown) outside the system passes through the raw material gas supply pipe L1 and the three-way valve V1, and enters the room temperature ¹¹ CO ₂ adsorption column 5 as shown in FIG. introduced, ¹¹ CO ₂ in the raw material gas is temporarily adsorbed on the ¹¹ CO ₂ adsorption column 5. The raw material gas from which ¹¹ CO ₂ has been separated by this adsorption treatment passes through the pipe L3, the first state six-way valve V2, the pipe L8, the three-way valve V3, the pipe L9, the exhaust pipe L10, and the edge cut-off valve V7, and is discharged out of the system. Is done.

After confirming that the ¹¹ CO ₂ adsorption amount in the ¹¹ CO ₂ adsorption column 5 has reached a predetermined value by the RI monitor 16, the supply of the source gas is stopped.

Next, the three-way valve V1 is switched to communicate with the hydrogen gas supply pipe L2 and the pipe L3, and as shown in FIG. 3, the six-way valve V2 is switched to set the second state to the pipe L3, the six-way valve V2, the pipes L4, ¹¹ CH _4. The adsorption column 8, the pipe L5, the six-way valve V2, the pipe L8, the three-way valve V3, and the pipes L9 and L10 are connected.

^{In the 11} CH ₄ generation step, a carrier gas containing nitrogen gas as a main component and containing about 10% of hydrogen gas is introduced into the ¹¹ CO ₂ adsorption column 5 through the hydrogen gas supply pipe L2, the three-way valve V1, and the pipe L3, The ¹¹ CO ₂ adsorption column 5 is heated by a heating device. By this heat treatment, ¹¹ CO ₂ is desorbed from the ¹¹ CO ₂ adsorption column 5.

The desorbed ¹¹ CO ₂ is introduced into the ¹¹ CH ₄ conversion column 6 heated by the heating device together with the carrier gas, contacts the reduction catalyst, and is converted to ¹¹ CH ₄ by the hydrogen gas in the carrier gas.

¹¹ CH ₄ produced in this ^manner, 11 are introduced into CH ₄ purification column ^7, adsorbed to the ^{adsorbent 11} CO ₂ or the like of unreacted filled in ¹¹ CH ₄ purification column 7 accompanying the 11 CH ₄ Is done. By this adsorption treatment, unreacted ¹¹ CO _{2 and the} like are separated from ¹¹ CH ₄ .

^{In the 11} CH ₄ adsorption step, ¹¹ CH ₄ is introduced into the ¹¹ CH ₄ adsorption column 8 at room temperature through the pipe L3, the six-way valve V2, and the pipe L4, and is temporarily adsorbed on the ¹¹ CH ₄ adsorption column 8. ¹¹ CH ₄ unreacted hydrogen gas introduced into to ¹¹ CH ₄ adsorption column 8 entrained like is to pass intact, pipe L5, hexagonal valve V2, the pipe L8, three-way valve V3, the pipe L9, exhaust pipe L10 , It passes through the edge cut valve V7 and is discharged out of the system.

The radioactivity measured in the RI monitor 16 and 17 at this ^{time, 11} CO ₂ 11 CO ₂ adsorption amount of the adsorption column 5 ^decreases, 11 CH ₄ reach the ¹¹ CH ₄ adsorption amount predetermined value in the adsorption column 8 After confirming that the carrier gas has been supplied, stop supplying the carrier gas.

The ¹¹ CH ₄ adsorption step includes a purge step for purging the inside of the ¹¹ CH ₄ adsorption system 3. First, the three-way valve V3 is closed and the edge cut valve V6 is opened, and the six-way valve V2 is switched to the first state as shown in FIG.

The He gas supplied from the He supply pipe L6 in this state is the edge cut valve V6, the six-way valve V2, the pipe L4, the ¹¹ CH ₄ adsorption column 8, the pipe L5, the six-way valve V2, the pipe L7, the exhaust pipe L10, and the edge cut valve V7. Then, these pipes, valves, and hydrogen gas remaining in the ¹¹ CH ₄ adsorption column 8 are discharged out of the system. After supplying a predetermined amount of He gas, the three-way valve V3 is switched to connect the pipe L9 and the pipe L11, and the edge cut-off valve V7 is closed. In this way, the pipes L7, L9, L11 are communicated.

Next, the ¹¹ CH ₄ adsorption column 8 is heated by a heating device. By this heat treatment, ¹¹ CH ₄ is desorbed from the ¹¹ CH ₄ adsorption column 8.

^{In the 11} CH ₃ I synthesis step, the desorbed ¹¹ CH ₄ is transferred by He gas, and passes through the pipe L5, the six-way valve V2, the pipes L7, L9, the three-way valve V3, the pipe L11, and the three-way valve V4, and the ¹¹ CH ₃ I synthesis. Introduced into system 4. The introduced ¹¹ CH ₄ includes a pipe L 12, an iodine column 10, an ¹¹ CH ₃ I synthesis column 11, an ¹¹ CH ₃ I purification column 12, an ¹¹ CH ₃ I adsorption column 13, a three-way valve V 5, a circulation pipe L 13, and a circulation pump 19. And return to the three-way valve V4 to circulate through these pipes, valves and columns.

Thus, the iodine column 10 is heated by the heating device in a state where ¹¹ CH ₄ is circulating in the ¹¹ CH ₃ I synthesis system 4. By this heat treatment, iodine is vaporized, and this iodine gas and ¹¹ CH ₄ are mixed.

The mixed ¹¹ CH ₄ and iodine gas are introduced into the ¹¹ CH ₃ I synthesis column 11 and heated by a heating device. By this heat treatment, ¹¹ CH ₄ and iodine gas undergo a synthesis reaction to synthesize ¹¹ CH ₃ I.

Thus synthesized ¹¹ CH ₃ I ^is 11 introduced into the CH ₃ I purification column ^12, 11 CH ₃ ^{adsorption 11} CO ₂ or the like of unreacted entrained in I is filled to ¹¹ CH ₃ I purification column 12 Adsorbed to the agent. The adsorption ^{treatment, 11} CO ₂ or the like from 11 CH ₃ I is separated.

¹¹ CO ₂ is ¹¹ CH ₃ I separated is introduced into the room of ¹¹ CH ₃ I adsorption column 13, the ¹¹ CH ₃ I adsorption column 13 to ¹¹ CH ₃ I is temporarily adsorbed. ¹¹ CH ₃ entrained in I with ¹¹ CH ₃ unreacted introduced into I purification column 12 ¹¹ CH ₄ is directly passed through, to continue the circulation, are introduced into iodine column 10 again, as described above, Mixing with iodine gas, synthesis reaction, etc. are repeated.

Then, after confirming that the ¹¹ CH ₃ I adsorption amount in the ¹¹ CH ₃ I adsorption column 13 has reached a predetermined value by the RI monitor 18, the circulation pump 19 is stopped to stop the circulation, and the three-way valves V 4 and V 5 are turned on. The pipes L11, L12, L14 are communicated by switching.

Next, the ¹¹ CH ₃ I adsorption column 13 is heated by a heating device. By this heat treatment, ¹¹ CH ₃ I is desorbed from the ¹¹ CH ₃ I adsorption column 13. The detached ¹¹ CH ₃ I is transferred by He gas introduced from the He supply pipe L6, and is recovered as a product through the pipes L12 and L14 and the three-way valves V10 and V11. Thereby, ¹¹ CH ₃ I is obtained.

Further, when ¹¹ CH ₃ OTf is synthesized using ¹¹ CH ₃ I obtained in this way, the three-way valve V10 is switched to select the pipe L17, and ¹¹ CH ₃ I is replaced with ¹¹ CH ₃ OTf synthesis column. 15 is introduced. ¹¹ CH ₃ I comes into contact with AgOTf heated by the heating device and becomes ¹¹ CH ₃ OTf. The ¹¹ CH ₃ OTf is recovered as a product through the pipe L18, the three-way valve V11, and the pipe L14. Thereby, ¹¹ CH ₃ OTf is obtained.

As described above, in the present embodiment, ¹¹ CH ₄ is temporarily adsorbed by the ¹¹ CH ₄ adsorption column 8 to remove unreacted hydrogen gas accompanying ¹¹ CH _4. The generation of impurities due to the reaction is suppressed, and clogging in the ¹¹ CH ₃ I synthesis column 11 is reduced. As a result, the synthesis reaction is stabilized and maintenance work such as washing and replacement of the ¹¹ CH ₃ I synthesis column 11 is reduced, so that the reliability is sufficiently improved and the continuous synthesis of ¹¹ CH ₃ I is possible. A methyl production apparatus and a methyl iodide production method can be provided.

Further, in the present embodiment, the ¹¹ CH ₄ adsorption system 3 includes a He supply pipe L6 for supplying He gas. Therefore, the inside of the ¹¹ CH ₄ adsorption system 3 is purged, and unreacted hydrogen gas is preferably used. It is discharged out of the system.

In the present ^embodiment, 11 CH ₄ generation system 2 is provided with the ¹¹ CO ₂ adsorption column 5 for concentrating ¹¹ CO ₂ temporarily adsorbing the ¹¹ CO ₂ contained in the raw material, iodide The amount of gas flowing in the methyl production apparatus 1 is reduced, gas circulation in the ¹¹ CH ₃ I synthesis system 4 is suitably performed, the reaction efficiency is increased, and the power of the circulation pump 19 is reduced. As a result, the synthesis reaction is stabilized and the operating cost is reduced.

Further, in the present embodiment, since the ¹¹ CH ₃ OTf synthesis system 14 that synthesizes ¹¹ CH ₃ OTf using ¹¹ CH ₃ I is provided at the subsequent stage of the ¹¹ CH ₃ I synthesis system 4, the ¹¹ CH ₃ OTf can be obtained.

Further, in the present embodiment, since the three-way valve V10 is provided in the previous stage of the ¹¹ CH ₃ OTf synthesis system 14, switching between the final products ¹¹ CH ₃ I and ¹¹ CH ₃ OTf is facilitated.

As mentioned above, although this invention was concretely demonstrated based on the embodiment, this invention is not limited to the said embodiment. For example, in the above embodiment, as a configuration in which ¹¹ CH ₄ is temporarily adsorbed to an adsorbent such as Cabosphere packed in the ¹¹ CH ₄ adsorption column 8 and unreacted hydrogen gas accompanying ¹¹ CH ₄ is removed. However, ¹¹ CH ₄ may be temporarily adsorbed by another adsorbent or the like, and unreacted hydrogen gas accompanying ¹¹ CH ₄ may be removed. In short, ¹¹ CH ₄ is accompanied by ¹¹ CH ₃ I. It is only necessary that unreacted hydrogen gas introduced into the synthesis column 11 can be removed.

Further, in the above ^embodiment, although the methyl iodide manufacturing apparatus 1 having a ¹¹ CH ₃ OTf synthesis system 14 for synthesizing 11 _CH 3 ^OTf, be configured having no 11 _CH 3 OTf synthesis system 14 good.

^Further, comprises a 11 _CH 3 OTf synthesis system 14, the final product ¹¹ CH ₃ may be methyl triflate manufacturing apparatus as OTf.

In the above embodiment, the three-way valves V10 and V11 are provided as switching means. However, the three-way valve V11 may be eliminated and ¹¹ CH ₃ OTf may be recovered as it is.

In the above embodiment, piping is adopted as a transfer path for internal fluid such as ¹¹ CH ₄ , ¹¹ CH ₃ I, etc., and each column is communicated. For example, each column is blocked. It is good also as a structure which arrange | positions in this and uses the hole etc. which were formed in this block body as a transfer path, and communicates each column.

  In the above embodiment, the six-way valve V2 is switched to select each pipe, but another multi-way valve may be adopted to select each pipe.

Further, in the methyl iodide manufacturing apparatus 1 of the above embodiment, ¹¹ CH ₄ is configured to include an exhaust pipe L10 in the adsorption system 3, but the system with hydrogen gas with an exhaust pipe to the ^{11 CH} 3 _I synthesis system 4 It is good also as a structure discharged | emitted outside.

It is a schematic block diagram which shows the methyl iodide manufacturing apparatus which concerns on this embodiment. It is a schematic block diagram which shows the methyl iodide manufacturing apparatus at the time of setting the six-way valve in FIG. 1 to a 1st state. It is a schematic block diagram which shows the methyl iodide manufacturing apparatus at the time of setting the six-way valve in FIG. 1 to a 2nd state. It is a schematic block diagram which shows the methyl iodide manufacturing apparatus by the conventional vapor phase method.

Explanation of symbols

1 ... Methyl iodide manufacturing apparatus, ^{2 ...} 11 CH ₄ generation system, ^{3 ...} 11 CH ₄ adsorption system, ^{4 ...} 11 CH ₃ I synthesis system, ^{5 ...} 11 CO ₂ adsorption column ⁽¹¹ CO ₂ adsorption chamber), 11 ... ¹¹ CH ₃ I synthesis column (reactor), 14... ¹¹ CH ₃ OTf synthesis system, L 6... He supply pipe (purge path), L 14... Product pipe (path for collecting ¹¹ CH ₃ I), L 17, L 18. (A route for supplying ¹¹ CH ₃ I to the ¹¹ CH ₃ OTf synthesis system and recovering ¹¹ CH ₃ OTf), V10, V11... Three-way valve (switching means).

Claims (5)

¹¹ by using the raw material gas and hydrogen gas containing CO ₂ to generate the ¹¹ CH ^_4, a methyl iodide manufacturing apparatus for synthesizing ¹¹ CH ₃ I by using the 11 CH ₄ and iodine gas,
An ¹¹ CO ₂ adsorption column filled with a first adsorbent that temporarily adsorbs ¹¹ CO ₂ contained in the source gas and separates ¹¹ CO ₂ from the source gas, and a subsequent stage of the ¹¹ CO ₂ adsorption column And a ¹¹ CH ₄ conversion column filled with a reduction catalyst for converting ¹¹ CO ₂ into ¹¹ CH ₄ by hydrogen gas, and an unreacted that is provided in the subsequent stage of the ¹¹ CH ₄ conversion column and accompanied by ¹¹ CH ₄ ¹¹ and CH ₄ purification column the second adsorbent is filled to separate the ¹¹ CO ₂ unreacted from ¹¹ CO ₂ was allowed to adsorb ¹¹ CH ₄ of the ¹¹ CH ₄ generation system having,
The provided after the ¹¹ CH _4-generating system ^has a ¹¹ CH ₄ adsorption columns third adsorbent is filled to temporarily adsorb 11 CH ^_4, unreacted accompanying the 11 CH ₄ hydrogen gas and ¹¹ CH ₄ adsorption system for removing,
The ¹¹ CH ₄ provided after the adsorption ^system, equipped with a ¹¹ CH ₃ I synthesis system with ¹¹ CH ₃ I synthesis column for synthesizing ¹¹ CH ₃ I by combining reaction of the iodine gas 11 CH ₄ An apparatus for producing methyl iodide. The methyl iodide production apparatus according to claim 1, wherein the ¹¹ CH ₄ adsorption system includes a purge path for supplying a purge fluid. Downstream of the ¹¹ CH ₃ I synthesis system comprises a ¹¹ CH ₃ OTf synthesis system for synthesizing the ¹¹ CH ₃ OTf using the ¹¹ CH ₃ I,
And a switching means for selectively switching between a path for recovering the ¹¹ CH ₃ I and a path for supplying the ¹¹ CH ₃ I to the ¹¹ CH ₃ OTf synthesis system and recovering the ¹¹ CH ₃ OTf. The methyl iodide production apparatus according to claim 1 or 2, characterized in that Generates ¹¹ CH ₄ by using a raw material gas and hydrogen gas containing ¹¹ CO ^_2, a Ruyo c methyl manufacturing process to synthesize ¹¹ CH ₃ I by using the 11 CH ₄ and iodine gas,
¹¹ CO ₂ to temporarily temporarily adsorbing the ¹¹ CO ₂ to ¹¹ CO ₂ adsorption column in which the first adsorbent is filled to be adsorbed, ¹¹ CO ₂ adsorption step of separating the ¹¹ CO ₂ from the feed gas When,
After the ¹¹ CO ₂ adsorption step, ¹¹ CO ₂ is converted to ¹¹ CH ₄ by hydrogen gas , and then ¹¹ CO ₂ is adsorbed to an ¹¹ CH ₄ purification column packed with a _second adsorbent that adsorbs ¹¹ CO ₂ . and ¹¹ CH ₄ production step of separating the ¹¹ CO ₂ unreacted entrained from ¹¹ CH ₄ by the ¹¹ CH _4,
After the ¹¹ CH ₄ production ^step, non accompanying the 11 CH ₄ the third ¹¹ adsorbent filled in CH ₄ temporarily ¹¹ CH ₄ adsorption columns to adsorb ¹¹ CH ₄ to temporarily adsorb An ¹¹ CH ₄ adsorption step for removing hydrogen gas in the reaction ;
And ¹¹ CH ₃ I synthesis step of synthesizing ¹¹ CH ₃ and ¹¹ CH ₃ I by synthesizing ¹¹ CH ₄ and iodine gas after the ¹¹ CH ₄ adsorption step. . It generates ¹¹ CH ₄ by using a raw material gas and hydrogen gas containing ¹¹ CO ^_2, to synthesize a ¹¹ CH ₃ I by using the 11 CH ₄ and iodine ^{gas, 11} CH ₃ OTf with 11 CH ₃ I An apparatus for producing methyl triflate,
An ¹¹ CO ₂ adsorption column filled with a first adsorbent that temporarily adsorbs ¹¹ CO ₂ contained in the source gas and separates ¹¹ CO ₂ from the source gas, and a subsequent stage of the ¹¹ CO ₂ adsorption column And a ¹¹ CH ₄ conversion column filled with a reduction catalyst for converting ¹¹ CO ₂ into ¹¹ CH ₄ by hydrogen gas, and an unreacted that is provided in the subsequent stage of the ¹¹ CH ₄ conversion column and accompanied by ¹¹ CH ₄ ¹¹ and CH ₄ purification column the second adsorbent is filled to separate the ¹¹ CO ₂ unreacted from ¹¹ CO ₂ was allowed to adsorb ¹¹ CH ₄ of the ¹¹ CH ₄ generation system having,
The provided after the ¹¹ CH ₄ generation system has a third 3 ¹¹ CH ₄ adsorption column adsorbent filled in for temporarily adsorbing the ¹¹ CH ^_4, unreacted accompanying the 11 CH ₄ hydrogen An ¹¹ CH ₄ adsorption system to remove gas;
Provided after the ¹¹ CH ₄ adsorption ^system, a ¹¹ CH ₃ I synthesis system with ¹¹ CH ₃ I synthesis column for synthesizing ¹¹ CH ₃ I by combining reaction of the iodine gas 11 CH _4,
The ¹¹ CH ₃ provided after the I synthesis ^system, characterized in that it comprises a and a ¹¹ CH ₃ OTf synthesis system with ¹¹ CH ₃ OTf synthesis column for synthesizing ¹¹ CH ₃ OTf with 11 CH ₃ I Methyl triflate production equipment.

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