KR20230011728A - System and method for solvent recovery in the diborane manufacturing process - Google Patents

Abstract

One embodiment of the present invention may provide a solvent recovery system for producing diborane, comprising: a first chamber which heats a liquid mixture to evaporate a solvent and discharges the mixture at a preset first concentration; a first gas outlet formed in an upper area of the first chamber and discharging gas evaporated in the first chamber; a first liquid outlet formed in a lower area of the first chamber and discharging a mixture of the first concentration; a stirring device for stirring the mixture in the first chamber; a second chamber for reheating the mixture of the first concentration discharged from the first chamber to evaporate the solvent; a second gas outlet formed in an upper area of the second chamber and discharging gas evaporated in the second chamber; and a recovery solvent chamber for storing the solvent evaporated in the first chamber and the second chamber in a liquid state. The recovery efficiency of organic solvents can be enhanced.

Description

Solvent recovery system and method in diborane production {SYSTEM AND METHOD FOR SOLVENT RECOVERY IN THE DIBORANE MANUFACTURING PROCESS}

The present invention relates to a solvent recovery system and method for producing diborane, and more particularly, to a solvent capable of distilling waste solvent to a predetermined concentration through a primary distillation process and maximizing solvent recovery through a secondary distillation process. It relates to a recovery system and method.

Diborane (diborane or diborane) is a compound of boron and hydrogen with the chemical formula B ₂ H ₆ . At room temperature, it is a colorless gas with a sweet odor. Since diborane mixes well with air, it is easy to make an explosive mixture, and it is widely used as a rocket propellant because it has the property of spontaneously igniting when it comes into contact with moist air. In addition, diborane gas is used as a P-type dopant in semiconductor equipment and is widely used in the electronic industry and its applications.

Conventional techniques for producing diborane include a synthesis method by reacting BF ₃ and LiH, a method using BCl ₃ and LiAlH ₄ , and a method using NaBH ₄ and three raw materials (BF ₃ , sulfuric acid, and I). are being introduced

NaBH ₄ (sodium borohydride) and BF ₃ (Boron trifluoride) are reacted to produce diborane (B ₂ H ₆ : diborane) containing impurities, and purified through adsorption and distillation to obtain high-purity diborane (B ₂ H ₆ : diborane). diborane) can be produced. To prepare diborane (B2H6:diborane) in the reaction unit, an ether-based solvent (for example, triglyme; triethylene glycol dimethyl ether; C ₈ H ₁₈ O ₄ or tetraglyme; tetraethylene glycol dimethyl ether;

C ₁₀ H ₂₂ O ₅ , Diglyme; Diethylene glycol dimethyl ether; C ₆ H ₁₄ O ₃ etc.) can be used.

Prior literature: Korean Patent Publication 10-2021-0016075

The prior literature discloses a diborane manufacturing process, and a process of recovering an ether-based solvent used in the diborane manufacturing process by a distillation process in an evaporator.

The organic solvent used in the diborane synthesis process can be recovered and reused by a distillation process after diborane gas is produced. At this time, methods for increasing the recovery efficiency of organic solvents are being studied.

In one embodiment of the present invention, in order to solve the above problems, an object of the present invention is to provide a solvent recovery system and method during diborane production that can increase the recovery efficiency of the organic solvent.

One embodiment of the present invention, a first chamber for heating the liquid mixture to evaporate the solvent and discharging the mixture to a predetermined first concentration, formed in the upper region of the first chamber, in the first chamber A first gas outlet for discharging evaporated gas, a first liquid outlet formed in a lower region of the first chamber and discharging the mixture having the first concentration, and an agitator for stirring the mixture in the first chamber. And, a second chamber for reheating the mixture of the first concentration discharged from the first chamber to evaporate the solvent, and a second chamber formed in an upper region of the second chamber and discharging the gas evaporated in the second chamber. It is possible to provide a solvent recovery system when preparing diborane, including a gas outlet and a recovery solvent chamber for storing the solvent evaporated in the first chamber and the second chamber in a liquid state.

The second chamber further includes a plurality of open containers containing the mixture of the first concentration discharged from the first chamber, a conveying unit for moving the plurality of open containers, and an extraction port for extracting the open container where the distillation process is completed. can include

At least one of the first gas outlet and the second gas outlet may be connected to the recovery solvent chamber.

The solvent recovery system may further include a controller that controls opening and closing of the first liquid outlet, and a controller that controls operation of the controller according to the concentration of the mixture inside the first chamber.

The solvent recovery system may further include a torque sensing unit for sensing a torque of the stirring device, and the control unit may calculate the waste solvent concentration according to the value detected by the torque sensing unit.

The solvent recovery system further includes a first level sensor disposed in the first chamber to measure the volume of the mixture inside the first chamber, and a second level sensor disposed in the recovery solvent chamber to measure the volume of the recovered solvent. The control unit may calculate the concentration of the waste solvent by calculating a solvent recovery rate from the measured amounts of the first level sensor and the second level sensor.

Another embodiment of the present invention, a first evaporation step of evaporating the solvent by distilling the liquid waste solvent generated after the diborane synthesis process introduced into the container unit through the liquid inlet at a first temperature, and the waste solvent present in the container unit detecting the concentration of the solvent; discharging the waste solvent in the container to the outside when the concentration of the waste solvent in the container is equal to or greater than a predetermined concentration; and discharging the discharged waste solvent to a second temperature higher than the first temperature. It is possible to provide a solvent recovery method during diborane production comprising a second evaporation step of evaporating the solvent by distillation at a temperature.

In the first evaporation step of evaporating the solvent, the inside of the container part may be maintained in a vacuum, and the temperature inside the container part may be maintained at 90° C. or less.

According to one embodiment of the present invention, it is possible to obtain a solvent recovery system and method capable of increasing the recovery efficiency of the organic solvent in the diborane production process.

1 is a block diagram of a solvent recovery system when producing diborane according to an embodiment of the present invention.
2 is a block diagram of a solvent recovery system when producing diborane according to another embodiment of the present invention.
3 is a block diagram of a solvent recovery system when producing diborane according to another embodiment of the present invention.
4 is a block diagram of a solvent recovery system when producing diborane according to another embodiment of the present invention.
5 is a process flow chart of a solvent recovery method in producing diborane according to another embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a solvent recovery system in producing diborane according to an embodiment of the present invention.

The solvent recovery system 100 according to the present embodiment may constitute a part of a diborane synthesis system. 1 shows an example of the entire diborane synthesis system.

Referring to FIG. 1 , in the mixing chamber 101, an ether-based solvent (eg, diglyme) and NaBH ₄ powder may be respectively introduced and mixed to form a mixed solution. A powder transfer pump, a liquid pump, etc. may be further provided to stably supply the NaBH ₄ powder and the diglyme solvent to the mixing chamber 101 . To prepare diborane (B ₂ H ₆ ), NaBH ₄ powder may be dissolved in diglyme in a mixing chamber at room temperature (25° C.) to form a mixed solution. In the mixing chamber 101, NaBH ₄ may be dissolved in the diglyme solvent through a built-in stirrer. At this time, the upper part of the raw material in the first chamber may be maintained at a pressure lower than atmospheric pressure by removing impurities with an inert gas such as nitrogen and using a vacuum pump.

The mixed solution thus mixed may be injected into the synthesis chamber 102 . Before the mixed solution is injected into the synthesis chamber 102, it may be purged with an inert gas to maintain a pressure lower than that of the mixing chamber 101 after removing impurities. In addition, the mixing chamber 102 may be positioned at a lower position than the mixing chamber 101 so that the mixed solution is injected using gravity. The mixed solution may be transferred from the mixing chamber 101 to the synthesis chamber 102 through a pipe connected between the mixing chamber 101 and the synthesis chamber 102 and valve control. In the synthesis chamber 102, a reaction gas in which impurities and diborane gas are mixed may be formed by injecting BF ₃ gas at a constant rate and reacting the mixed solution with the BF ₃ gas. In the synthesis chamber 102, BF ₃ gas is directly injected into the mixed solution to react. The injection rate of the BF ₃ gas may be adjusted to induce the synthesis of the solvent and the intermediate.

In this embodiment, the mixing chamber 101 and the synthesis chamber 102 are separately illustrated and described, but the solvent diglyme, NaBH ₄ powder, and BF ₃ gas may be simultaneously injected into one chamber. As shown in the present embodiment, when the mixing chamber and the synthesis chamber are installed separately, mixing and reaction in the synthesis chamber are continuously performed by adjusting the amount of NaBH ₄ and BF ₃ gases introduced into the synthesis chamber 102 can make it In addition, while the diborane gas is synthesized in the synthesis chamber, a process of generating a mixed solution in the mixing chamber and supplying the mixed solution to the synthesis chamber may be continuously performed. On the other hand, in the case of simultaneously injecting diglyme, NaBH ₄ powder, and BF ₃ gas into one chamber, there is a disadvantage that additional work cannot be performed until the diborane gas process using the injected materials is finished. The concentration of synthesized diborane gas can be kept constant by accurately adding the ratio.

The gas synthesized in the synthesis chamber 102 is a mixture of diborane gas and gaseous impurities. Therefore, diborane gas from which impurities are removed may be obtained through a purification process of removing impurities from the mixed gas synthesized in the synthesis chamber 102 . The purification process may use an adsorption method using an adsorbent and a method using a difference in boiling point of gas.

The solvent recovery system 100 according to the present embodiment receives the waste solvent remaining after the reaction in the synthesis chamber 102, recovers the diglyme solvent through a predetermined purification process, and transfers the recovered diglyme solvent to the mixing chamber ( 101) can be passed back.

The solvent recovery system 100 according to the present embodiment includes a first chamber 110, a first gas outlet 120, a first liquid outlet 130, an agitator 140, and a second chamber 150. , a second gas outlet 160, and a recovery solvent chamber 170.

The first chamber 110 is connected to the rear end of the reaction chamber 102 and can receive waste solvent remaining after reaction in the reaction chamber 102 . In the waste solvent flowing into the first chamber 110, impurities remaining after NaBH ₄ and BF ₃ react are dissolved in the diglyme solvent. The first chamber 110 may be equipped with means for heating the waste solvent in order to recover pure diglyme solvent from the waste solvent containing impurities. The waste solvent may be heated in the first chamber 110 to evaporate the pure diglyme solvent into a gaseous state by a distillation process. In order to increase the evaporation efficiency of the diglyme solvent in the container part, a certain level of vacuum may be maintained inside the container part. In order to maintain the degree of vacuum, a constant flow rate of nitrogen may be supplied to the container part. As such, if the pressure inside the container is lowered than the atmospheric pressure, the effect of lowering the boiling temperature of diglyme can be obtained. For example, by configuring the container unit as a double container, supplying hot oil between the inner container and the outer container, and maintaining the pressure inside the inner container at 50 to 100 torr, the boiling point at atmospheric pressure The effect of lowering the boiling temperature of diglyme, which is about 162 ° C, to about 87 ° C can be obtained. Therefore, the distillation process may be performed while maintaining the temperature inside the container unit at 90° C. or less.

The distillation process in the first chamber 110 may proceed only to the extent that the waste solvent has considerable fluidity. When the distillation process in the first chamber is excessively performed, the powder concentration of the waste solvent increases, which may cause problems such as clogging of the inner tube by the slurry or remaining of the slurry in a solid state in the first chamber. Therefore, in the present embodiment, the distillation process may be performed and the waste solvent may be discharged only until the waste solvent in the first chamber 110 reaches a predetermined first concentration.

The first gas outlet 120 is a passage through which the diglyme solvent evaporated in the first chamber 110 is extracted into the recovery solvent chamber 170 . A valve may be additionally formed at the first gas outlet 120 to adjust the extraction amount of the diglyme solvent of the gas component extracted from the first chamber 110 .

The first liquid outlet 130 is a passage for evaporating the solvent through the distillation process in the first chamber 110 and discharging the remaining slurry state waste solvent. The first liquid outlet 130 is disposed at the lower end of the first chamber 110 to discharge the waste solvent to the outside by gravity. In addition, a separate pump may be connected to the liquid outlet to facilitate discharge of the waste solvent in the slurry state.

The stirring device 140 may increase evaporation efficiency during the distillation process by stirring the waste solvent in the first chamber 110 . The stirring device 140 may be implemented in the form of a rotary blade, and a motor for rotating the stirring device may be mounted.

The second chamber 150 may evaporate the solvent by reheating the mixture having the first concentration discharged from the first chamber. A means for increasing the temperature inside the second chamber 150 may be installed in order to recover pure solvent from the waste solvent containing impurities. The distillation process in the second chamber 150 may be performed at a higher temperature than the distillation process in the first chamber. Since the distillation process in the first chamber 110 progresses the concentration of the waste solvent only to the first concentration that is somewhat fluid due to the problem of solidification of the slurry, the mixture discharged from the first chamber still contains a considerable amount of solvent there is. In the second chamber 150, a distillation process may be additionally performed on the mixture discharged from the first chamber to distill the remaining organic solvent. In this case, in order to reduce the clogging of pipes caused by the solidification of the waste solvent or the problem remaining on the wall of the chamber, a separate waste solvent storage container is used, and the solidified waste solvent is discarded together with the storage container after the distillation process is performed in the storage container. It can be.

The second gas outlet 160 is a passage through which the solvent evaporated in the second chamber 150 is extracted to the recovery solvent chamber 170 . A valve may be additionally formed at the second gas outlet 160 to adjust the solvent extraction amount of the gas component extracted from the second chamber 150 .

The recovery solvent chamber 170 may cool and store the gaseous solvent evaporated in the first chamber 110 and the second chamber 150 as a solvent in a liquid state. The recovery solvent chamber 170 may include a cold trap for cooling the solvent injected in a gaseous state, a storage unit for storing the cooled solution, and a pump for transferring the stored solution to the mixing chamber 101 . In this embodiment, the first gas outlet 120 and the second gas outlet 160, from which the solvent of the gas component evaporated in the first chamber 110 and the second chamber 150 is extracted, are recovered through the pipe. Although shown as being connected to the solvent chamber 170, at least one of the first gas outlet 120 and the second gas outlet 160 may not be directly connected to the recovery solvent chamber 170. That is, when the first gas outlet 120 and the second gas outlet 160 are directly connected to the recovered solvent chamber 170 through a pipe, evaporation generated by the operation of the first chamber and the second chamber A continuous process is possible to store the recovered solvent directly in the recovery solvent chamber. However, the first gas outlet 120 and the second gas outlet 160 may be connected to separate solvent storage chambers.

In the solvent recovery system according to the present embodiment, the fluidity of the waste solvent and the concentration of the recovered solvent may be increased by distilling the waste solvent only up to a predetermined concentration in the first chamber, and the distillation process in the second chamber additionally proceeds. The solvent recovery rate can be maximized without the fluidity problem of the waste solvent.

2 is a configuration diagram of a second chamber in a solvent recovery system according to another embodiment of the present invention.

Referring to FIG. 2 , in the solvent recovery system 200 according to the present embodiment, the second chamber 250 may include a plurality of open containers 252, a transfer unit 253, and an extraction port 254.

The open container 252 is a container capable of containing a mixture of a first concentration discharged from the first chamber. The open container 252 may be a container with one side open so as to facilitate injection of the mixture from the first liquid outlet 251 through which the mixture having the first concentration is discharged from the first chamber. In addition, the open container may be formed of a material that can be disposed of together with the slurry present therein since the waste solvent is changed into a hard solid form when the distillation process inside the second chamber is completed.

The transfer unit 253 may be formed in a rail shape inside the second chamber and move the plurality of open containers inside the second chamber. While the open container is being moved along the transfer unit 253, a distillation process inside the second chamber may be performed, and the organic solvent may be evaporated from the waste solvent contained in the open container. The shape or length of the transfer unit 253 may be variously implemented according to the type or amount of the organic solvent to be evaporated.

The extraction hole 254 is formed on one side of the second chamber, and an open container containing the waste solvent in which the distillation process is completed can be extracted. A separate opening and closing door may be formed in the extraction port 254 so that the door is opened only when the open container is extracted. In this embodiment, the waste solvent contained in the open container extracted through the spout may be in a state in which components of the organic solvent are mostly evaporated and powder components are solidified.

In the solvent recovery system according to the present embodiment, a means for increasing the temperature inside the second chamber 250 may be installed in the second chamber 250 to distill and recover the pure solvent from the waste solvent containing impurities. In the distillation process in the first chamber, because of the problem of solidification of the slurry, the concentration of the waste solvent is only increased to the first concentration, which is fluid to some extent, so that the mixture discharged from the first chamber still contains a considerable amount of solvent. In the second chamber 250, a distillation process may be additionally performed on the mixture discharged from the first chamber to distill the remaining organic solvent. In this case, in order to reduce the clogging of the pipe caused by the solidification of the waste solvent or the problem of remaining on the wall of the chamber, an open container, which is a separate waste solvent storage container, is used, and the solidified waste solvent after the distillation process is performed in the storage container can be discarded with

3 is a configuration diagram of a solvent recovery system according to still another embodiment of the present invention.

Referring to FIG. 3 , the solvent recovery system 300 according to the present embodiment includes a first chamber 310, a first gas outlet 320, a first liquid outlet 330, a stirring device 340, It may include a second chamber 350, a second gas outlet 360, a recovery solvent chamber 370, a controller 380, and a controller 390.

The first chamber 310 is connected to the rear end of the reaction chamber (not shown) and can receive waste solvent remaining after reaction in the reaction chamber. In the waste solvent flowing into the first chamber 310, impurities remaining after NaBH ₄ and BF ₃ react are dissolved in the diglyme solvent. The first chamber 310 may be equipped with means for heating the waste solvent in order to recover pure diglyme solvent from the waste solvent containing impurities. The waste solvent may be heated in the first chamber 310 to evaporate the pure diglyme solvent into a gaseous state by a distillation process. In order to increase the evaporation efficiency of the diglyme solvent in the container part, a certain level of vacuum may be maintained inside the container part. In order to maintain the degree of vacuum, a constant flow rate of nitrogen may be supplied to the container part. As such, if the pressure inside the container is lowered than the atmospheric pressure, the effect of lowering the boiling temperature of diglyme can be obtained. For example, by configuring the container unit as a double container, supplying hot oil between the inner container and the outer container, and maintaining the pressure inside the inner container at 50 to 100 torr, the boiling point at atmospheric pressure The effect of lowering the boiling temperature of diglyme, which is about 162 ° C, to about 87 ° C can be obtained. Therefore, the distillation process may be performed while maintaining the temperature inside the container unit at 90° C. or less.

The distillation process in the first chamber 310 may proceed only to the extent that the waste solvent has considerable fluidity. When the distillation process in the first chamber is excessively performed, the powder concentration of the waste solvent increases, which may cause problems such as clogging of the inner tube by the slurry or remaining of the slurry in a solid state in the first chamber. Therefore, in the present embodiment, the distillation process may be performed and the waste solvent may be discharged only until the waste solvent in the first chamber 310 reaches a predetermined first concentration.

The first gas outlet 320 is a passage through which the diglyme solvent evaporated in the first chamber 310 is extracted into the recovery solvent chamber 370 . A valve may be additionally formed at the first gas outlet 320 to adjust the extraction amount of the diglyme solvent of the gas component extracted from the first chamber 310 .

The first liquid outlet 330 is a passage for evaporating the solvent through the distillation process in the first chamber 310 and discharging the remaining slurry state waste solvent. The first liquid outlet 330 is disposed at the lower end of the first chamber 310 to discharge the waste solvent to the outside by gravity. In addition, a separate pump may be connected to the liquid outlet to facilitate discharge of the waste solvent in the slurry state.

The stirring device 340 may increase evaporation efficiency during the distillation process by stirring the waste solvent in the first chamber 310 . The stirring device 340 may be implemented in the form of a rotating blade, and a motor for rotating the stirring device may be mounted.

The second chamber 350 may evaporate the solvent by reheating the mixture having the first concentration discharged from the first chamber. A means for increasing the temperature inside the second chamber 350 may be installed in order to recover pure solvent from the waste solvent containing impurities. The distillation process in the second chamber may be performed at a higher temperature than the distillation process in the first chamber. Since the distillation process in the first chamber 310 progresses the concentration of the waste solvent only to the first concentration that is somewhat fluid due to the problem of solidification of the slurry, the mixture discharged from the first chamber still contains a considerable amount of organic solvent has been In the second chamber 350, a distillation process may be additionally performed on the mixture discharged from the first chamber to distill the remaining organic solvent. In this case, in order to reduce the clogging of pipes caused by the solidification of the waste solvent or the problem remaining on the wall of the chamber, a separate waste solvent storage container is used, and the solidified waste solvent is discarded together with the storage container after the distillation process is performed in the storage container. It can be.

The second gas outlet 360 is a passage through which the solvent evaporated in the second chamber 350 is extracted to the recovery solvent chamber 370 . A valve may be additionally formed at the second gas outlet 360 to adjust the solvent extraction amount of the gas component extracted from the second chamber 350 .

The recovery solvent chamber 370 may cool the solvent of the gaseous component evaporated in the first chamber 310 and the second chamber 350 and store it as a liquid solvent. The recovery solvent chamber 370 may include a cold trap for cooling the solvent injected in a gaseous state, a storage unit for storing the cooled solution, and a pump for transferring the stored solution to the mixing chamber. In the present embodiment, the first gas outlet 320 and the second gas outlet 360 from which the solvent of the gas component evaporated in the first chamber 310 and the second chamber 350 are extracted are recovered through the pipe. Although shown as being connected to the solvent chamber 370, at least one of the first gas outlet 320 and the second gas outlet 360 may not be directly connected to the recovery solvent chamber 370. That is, when the first gas outlet 320 and the second gas outlet 360 are directly connected to the recovered solvent chamber 370 through a pipe, evaporation generated by the operation of the first chamber and the second chamber A continuous process is possible to store the recovered solvent directly in the recovery solvent chamber. However, the first gas outlet 320 and the second gas outlet 360 may be connected to separate solvent storage chambers.

The control unit 380 is disposed in the first liquid outlet 330 to control opening and closing of the liquid outlet. A discharge timing of the waste solvent in the first chamber may be determined by the opening and closing operation of the controller.

The control unit 390 may control the opening and closing operation of the control unit according to the concentration of the waste solvent in the first chamber. The method for the controller 390 to detect the concentration of the waste solvent inside the first chamber may be implemented in various ways, by closing the controller 380 until the concentration of the waste solvent inside the first chamber reaches a predetermined concentration. The distillation process is performed inside the first chamber, and when the concentration of the waste solvent is detected to be higher than a predetermined concentration, the controller 380 may be opened to discharge the waste solvent in a slurry state.

In this embodiment, the stirring device 340 may be disposed inside the first chamber 310 . The stirring device 340 may increase evaporation efficiency during the distillation process by stirring the waste solvent in the container unit. In the present embodiment, the stirring device 340 includes a central axis 341 disposed vertically at the center of the first chamber, a first rotation unit 343 disposed below the central axis, and an upper portion of the first rotation unit. It may include a second rotating part 342 to be. In addition, a motor 344 outside the first chamber may be connected to rotate the central axis. The rotation of the motor rotates the first rotation unit and the second rotation unit inside the first chamber to agitate the waste solvent. Shapes of the first rotation unit and the second rotation unit may be implemented in various ways.

The solvent recovery system 300 according to the present embodiment may further include a torque sensor 345 that detects torque of the stirring device 340 . The torque sensor 345 may be a sensor that measures the RPM of the motor 344 that rotates the stirring device. The stirring device 340 may be rotated to stir the waste solvent inside the first chamber. As the distillation process inside the first chamber progresses, the concentration of the powder in the waste solvent increases, so the torque applied to the agitator further increases. Accordingly, the RPM of the motor rotating the stirring device is further increased. The torque sensor 345 detects the RPM of the motor that rotates the stirring device, and when the RPM increases, it can detect that the concentration of the waste solvent in the first chamber has increased.

The control unit 390 recognizes that the concentration of the waste solvent has reached a certain concentration or higher when the RPM of the motor detected by the torque sensor 345 is detected as higher than a predetermined value, and opens the control unit 380 to control the first The waste solvent inside the chamber can be discharged.

For example, the powder density of the waste solvent when the waste solvent is injected into the first chamber may be about 5%. During the distillation process in the first chamber, the powder density of the waste solvent gradually increases. As the powder density of the waste solvent increases, the torque applied to the stirring device for stirring the waste solvent increases. Therefore, the RPM of the motor rotating the stirring device also increases. If the torque of the stirrer and the RPM value of the motor when the powder density of the waste solvent reaches about 10 to 20% are input into the controller in advance, the amount of waste solvent in the first chamber is determined by the RPM value of the motor detected by the torque sensor. The powder density can be detected. When the RPM value of the motor sensed by the torque sensor reaches a value corresponding to about 10 to 20% of the powder concentration of the waste solvent, the controller opens the controller to discharge the waste solvent in the first chamber through the first liquid outlet. can

4 is a configuration diagram of a solvent recovery system according to still another embodiment of the present invention.

Referring to FIG. 4 , the solvent recovery system 400 according to the present embodiment includes a first chamber 410, a first gas outlet 420, a first liquid outlet 430, a stirring device 440, The second chamber 450, the second gas outlet 460, the recovery solvent chamber 470, the controller 480, the controller 490, and the first level sensor 415 and the second level sensor 475 can include

The first chamber 410 is connected to the rear end of the reaction chamber (not shown) and can receive waste solvent remaining after reaction in the reaction chamber. In the waste solvent flowing into the first chamber 410, impurities remaining after NaBH ₄ and BF ₃ react are dissolved in the diglyme solvent. The first chamber 410 may be equipped with means for heating the waste solvent in order to recover pure diglyme solvent from the waste solvent containing impurities. The waste solvent may be heated in the first chamber 410 to evaporate the pure diglyme solvent into a gaseous state by a distillation process. In order to increase the evaporation efficiency of the diglyme solvent in the container part, a certain level of vacuum may be maintained inside the container part. In order to maintain the degree of vacuum, a constant flow rate of nitrogen may be supplied to the container part. As such, if the pressure inside the container is lowered than the atmospheric pressure, the effect of lowering the boiling temperature of diglyme can be obtained. For example, by configuring the container unit as a double container, supplying hot oil between the inner container and the outer container, and maintaining the pressure inside the inner container at 50 to 100 torr, the boiling point at atmospheric pressure The effect of lowering the boiling temperature of diglyme, which is about 162 ° C, to about 87 ° C can be obtained. Therefore, the distillation process may be performed while maintaining the temperature inside the container unit at 90° C. or less.

The distillation process in the first chamber 410 may proceed only to the extent that the waste solvent has considerable fluidity. When the distillation process in the first chamber is excessively performed, the powder concentration of the waste solvent increases, which may cause problems such as clogging of the inner tube by the slurry or remaining of the slurry in a solid state in the first chamber. Therefore, in the present embodiment, the distillation process may be performed only until the waste solvent in the first chamber 410 reaches a preset first concentration, and the waste solvent may be discharged.

The first gas outlet 420 is a passage through which the diglyme solvent evaporated in the first chamber 410 is extracted into the recovery solvent chamber 470 . A valve may be additionally formed at the first gas outlet 420 to adjust the extraction amount of the diglyme solvent of the gas component extracted from the first chamber 410 .

The first liquid outlet 430 is a passage for evaporating the solvent through the distillation process in the first chamber 410 and discharging the remaining slurry state waste solvent. The first liquid outlet 430 is disposed at the lower end of the first chamber 410 to discharge the waste solvent to the outside by gravity. In addition, a separate pump may be connected to the liquid outlet to facilitate discharge of the waste solvent in the slurry state.

The stirring device 440 may increase evaporation efficiency during the distillation process by stirring the waste solvent in the first chamber 410 . The stirring device 440 may be implemented in the form of a rotating blade, and a motor for rotating the stirring device may be mounted.

The second chamber 450 may evaporate the solvent by reheating the mixture having the first concentration discharged from the first chamber. The second chamber 450 may be equipped with a means for increasing the temperature inside the second chamber in order to recover the pure solvent from the waste solvent containing impurities. The distillation process in the second chamber may be performed at a temperature higher than the temperature of the distillation process in the first chamber. Since the distillation process in the first chamber 410 progresses the concentration of the waste solvent only to the first concentration that is somewhat fluid due to the problem of solidification of the slurry, the mixture discharged from the first chamber still contains a considerable amount of organic solvent has been In the second chamber 450, a distillation process may be additionally performed on the mixture discharged from the first chamber to distill the remaining organic solvent. In this case, in order to reduce the clogging of pipes caused by the solidification of the waste solvent or the problem remaining on the wall of the chamber, a separate waste solvent storage container is used, and the solidified waste solvent is discarded together with the storage container after the distillation process is performed in the storage container. It can be.

The second gas outlet 460 is a passage through which the solvent evaporated in the second chamber 450 is extracted to the recovery solvent chamber 470 . A valve may be additionally formed at the second gas outlet 460 to adjust the extraction amount of the solvent of the gas component extracted from the second chamber 450 .

The recovery solvent chamber 470 may cool and store the gaseous solvent evaporated in the first chamber 410 and the second chamber 450 as a liquid solvent. The recovery solvent chamber 470 may include a cold trap for cooling the solvent injected in a gaseous state, a storage unit for storing the cooled solution, and a pump for transferring the stored solution to the mixing chamber. In the present embodiment, the first gas outlet 420 and the second gas outlet 460 from which the solvent of the gas component evaporated in the first chamber 410 and the second chamber 450 are extracted are recovered through the pipe. Although shown as being connected to the solvent chamber 470, at least one of the first gas outlet 420 and the second gas outlet 460 may not be directly connected to the recovery solvent chamber 470. That is, when the first gas outlet 420 and the second gas outlet 460 are directly connected to the recovered solvent chamber 470 through a pipe, evaporation generated by the operation of the first and second chambers occurs. A continuous process is possible to store the recovered solvent directly in the recovery solvent chamber. However, the first gas outlet 420 and the second gas outlet 460 may be connected to separate solvent storage chambers.

The control unit 480 is disposed in the first liquid outlet 430 to control opening and closing of the liquid outlet 430 . A discharge timing of the waste solvent in the first chamber may be determined by the opening and closing operation of the controller.

The control unit 490 may control the opening and closing operation of the control unit according to the concentration of the waste solvent in the first chamber. The controller 490 detects the concentration of the waste solvent inside the first chamber in various ways. The controller 480 is closed until the concentration of the waste solvent inside the first chamber reaches a predetermined concentration. The distillation process is performed inside the first chamber, and when the concentration of the waste solvent is detected to be higher than a predetermined concentration, the controller 480 may be opened to discharge the waste solvent in a slurry state.

The solvent recovery system 400 according to the present embodiment may include a first level sensor 415 and a second level sensor 475 . The first level sensor 415 may measure the amount of waste solvent injected into the first chamber 410, and the second level sensor 475 may measure the amount of solvent stored in the recovery solvent chamber 470. can be measured In particular, in this embodiment, the second level sensor can measure only the capacity of the solvent recovered from the first chamber. When the solvent recovery system according to the present embodiment is operated, the waste solvent in the first chamber 410 is evaporated by the distillation process, so that the capacity of the waste solvent in the first chamber is reduced over time. . The first level sensor may detect that the capacity of the waste solvent inside the first chamber is reduced in this way. The diglyme solvent evaporated in the first chamber may be stored in the recovery solvent chamber 470 in a liquid state. Over time, the capacity of diglyme stored in the recovery solvent chamber 470 increases. The second level sensor may detect an increase in the diglyme solvent recovered from the first chamber.

In this embodiment, the controller 490 may detect the amount of waste solvent and the amount of recovered diglyme solvent from the first level sensor 415 and the second level sensor 475 . By calculating the amount of the detected waste solvent and the amount of the recovered diglyme solvent, the solvent recovery rate and the powder density of the waste solvent currently remaining in the first chamber can be calculated. The solvent recovery rate may be defined as a value obtained by dividing the volume of recovered solvent measured by the second level sensor by the volume of remaining waste solvent measured by the first level sensor. The concentration of the waste solvent may be defined as a value obtained by dividing the amount of powder (solute) contained in the waste solvent by the amount of diglyme solvent contained in the waste solvent. Although it is difficult to measure the amount of waste solvent powder in real time, the concentration of the waste solvent can be inferred by calculating the solvent recovery rate in real time. Therefore, in the present embodiment, the solvent recovery rate may be calculated using the capacity of the waste solvent measured by the first level sensor and the second level sensor and the capacity of the recovered diglyme solvent. In this embodiment, the control unit 490 recognizes that the concentration of the waste solvent in the first chamber has reached a certain concentration or higher when the solvent recovery rate reaches a certain value, and opens the controller 480 to open the waste solvent inside the first chamber. Solvent can be released.

For example, the powder density of the waste solvent when the waste solvent is injected into the first chamber may be about 5%. During the distillation process in the first chamber, the powder density of the waste solvent gradually increases. The solvent recovery rate is calculated using the amount of waste solvent detected by the first level sensor and the amount of recovered solvent detected by the second level sensor, and when the solvent recovery rate reaches 55% to 60%, the control unit opens the control unit. The waste solvent in the first chamber may be discharged through the liquid outlet.

In this embodiment, the operation of the controller is to detect the concentration of the waste solvent in the first chamber and adjust the opening and closing of the controller accordingly, and the second level sensor 475 can measure only the volume of the solvent recovered from the first chamber. It is preferable to be configured so that

5 is a process flow chart of a solvent recovery method in producing diborane according to another embodiment of the present invention.

Referring to FIG. 5 , the solvent recovery method 500 in producing diborane according to the present embodiment includes a first evaporation step of evaporating the solvent (501), a step of detecting the concentration of the waste solvent (502), and removing the waste solvent from the outside. It may include a step 503 of discharging to and a second evaporation step 504 of evaporating the solvent.

In the first evaporation step 501 of evaporating the solvent, the waste solvent introduced into the storage unit after gaseous diborane is synthesized in the diborane synthesis process may be evaporated by a distillation process at a first temperature. In the waste solvent, impurities remaining after NaBH ₄ and BF ₃ react are dissolved in the diglyme solvent. In order to increase the evaporation efficiency of the diglyme solvent in the container part, a certain level of vacuum may be maintained inside the container part. In order to maintain the degree of vacuum, a constant flow rate of nitrogen may be supplied to the container part. As such, if the pressure inside the container is lowered than the atmospheric pressure, the effect of lowering the boiling temperature of diglyme can be obtained. For example, by configuring the container unit as a double container, supplying hot oil between the inner container and the outer container, and maintaining the pressure inside the inner container at 50 to 100 torr, the boiling point at atmospheric pressure The effect of lowering the boiling temperature of diglyme, which is about 162 ° C, to about 87 ° C can be obtained. Therefore, the distillation process may be performed while maintaining the temperature inside the container unit at 90° C. or less.

In step 502 of detecting the concentration of the waste solvent, the concentration of the waste solvent remaining after the solvent is evaporated by the distillation process may be detected in real time. As a method of detecting the concentration of the waste solvent, torque applied to a stirring device for stirring the waste solvent in the container unit may be measured. As the solvent increases, the concentration of the powder mixed in the waste solvent increases, so the torque applied to the stirring device increases. Therefore, the concentration of the waste solvent can be detected by measuring the torque applied to the stirring device. Alternatively, the concentration of the waste solvent may be calculated by calculating the ratio of the volume of the waste solvent introduced into the container and the volume of the solvent evaporated by the distillation process. As a method for detecting the concentration of the waste solvent, the method used in the embodiment of FIG. 2 or FIG. 3 may be used.

In step 503 of discharging the waste solvent to the outside, when the concentration of the waste solvent reaches a certain level, the waste solvent in the storage unit may be discharged to the outside. When the concentration of the waste solvent detected in the step of detecting the concentration of the waste solvent is greater than or equal to a predetermined concentration, the distillation process may be stopped and the waste solvent may be discharged to the outside. If the powder concentration of the waste solvent is too high by the distillation process, the fluidity of the slurry is lowered, and as a result, a problem may occur that the slurry remains inside the container or the outlet is clogged. After discharging the waste solvent to the outside, a process of washing the inside of the container with a solvent may be added. If the slurry of the waste solvent remains in the container part, it may cause a problem in the continuous process. Therefore, the condition inside the container part for evaporating the waste solvent can be maintained by washing the inside of the container part with a solvent after discharging the waste solvent.

In the second evaporation step 504 of evaporating the solvent, the discharged waste solvent may be distilled at a second temperature higher than the first temperature to evaporate the solvent. In the first evaporation step, the boiling point of diglyme is lowered by lowering the pressure inside the container, so that the temperature inside the container can be relatively low. In the second evaporation step, the pressure inside the vessel may be maintained at atmospheric pressure. In the second evaporation step, the temperature inside the container may be higher than the first temperature in the first evaporation step. In the present embodiment, by proceeding with the second evaporation step, diglyme remaining in the waste solvent can be maximally distilled. After the second evaporation step is completed, almost no diglyme component remains, and waste in the form of solid powder components may be discharged.

Although the above has been described with reference to the preferred embodiments and examples of the present invention, those skilled in the art will variously modify the present invention within the scope not departing from the spirit and scope of the present invention described in the claims below. And it will be understood that it can be changed. For example, in the detailed description of the invention, the type of solvent recovered has been described as diglyme, but it can be applied to all ether-based solvents. These modified implementations should not be individually understood from the technical spirit or perspective of the present invention.

110: first chamber 150: second chamber
170: recovery solvent chamber

Claims (8)

a first chamber for heating the liquid mixture to evaporate the solvent and discharging the mixture to a predetermined first concentration;
a first gas outlet formed in an upper region of the first chamber and discharging gas evaporated in the first chamber;
a first liquid outlet formed in a lower region of the first chamber and discharging the mixture having the first concentration;
a stirrer for stirring the mixture in the first chamber;
a second chamber reheating the mixture having the first concentration discharged from the first chamber to evaporate the solvent;
a second gas outlet formed in an upper region of the second chamber and discharging gas evaporated in the second chamber; and
A recovery solvent chamber for storing the solvent evaporated in the first and second chambers in a liquid state.
Solvent recovery system in the manufacture of diborane comprising a.
According to claim 1,
The second chamber,
a plurality of open containers containing a mixture of a first concentration discharged from the first chamber;
a transfer unit for moving the plurality of open containers; and
Extraction port for extracting an open container after the distillation process is completed
Solvent recovery system for producing diborane, characterized in that it further comprises.
According to claim 1,
At least one of the first gas outlet and the second gas outlet,
Solvent recovery system when producing diborane, characterized in that connected to the recovery solvent chamber.
According to claim 1,
a controller controlling opening and closing of the first liquid outlet; and
A controller for controlling the operation of the control unit according to the concentration of the mixture inside the first chamber
Solvent recovery system for producing diborane, characterized in that it further comprises.
According to claim 4,
Torque sensing unit for sensing the torque of the stirring device
Including more,
The control unit calculates the waste solvent concentration according to the value detected by the torque sensor.
According to claim 4,
a first level sensor disposed in the first chamber to measure a volume of the mixture inside the first chamber; and
Further comprising a second level sensor disposed in the recovery solvent chamber to measure the volume of the recovered solvent,
The control unit calculates the concentration of the waste solvent by calculating the solvent recovery rate from the measured amounts of the first level sensor and the second level sensor.
A first evaporation step of evaporating the solvent by distilling the liquid waste solvent generated after the diborane synthesis process introduced into the container through the liquid inlet at a first temperature;
detecting the concentration of the waste solvent present in the container part;
discharging the waste solvent in the storage unit to the outside when the concentration of the waste solvent in the storage unit exceeds a predetermined concentration; and
A second evaporation step of evaporating the solvent by distilling the discharged waste solvent at a second temperature higher than the first temperature
Solvent recovery method in diborane production comprising a.
According to claim 7,
The first evaporation step of evaporating the solvent,
Keeping the inside of the container part in a vacuum,
Solvent recovery method in the production of diborane, characterized in that for maintaining the temperature inside the container part at 90 ℃ or less.

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