KR20230011727A - System and method for solvent recovery in the diborane manufacturing process - Google Patents

Abstract

The present invention provides a system and method for solvent recovery in a diborane manufacturing process to increase the recovery efficiency of organic solvents. According to one embodiment of the present invention, the system for solvent recovery in a diborane manufacturing process comprises: a container unit storing and evaporating a liquid waste solvent introduced through a liquid inlet; a gas outlet formed in the upper area of the container unit and discharging gas evaporated from the container unit; a recovery solvent storage unit in which the gas discharged through the gas outlet is cooled and stored in a liquid state; a liquid outlet formed in the lower area of the container unit and discharging the waste solvent remaining in the container unit; a stirring device stirring the waste solvent within the container unit; an adjustment unit adjusting the opening and closing of the liquid outlet; and a control unit controlling the operation of the adjustment unit according to the concentration of the waste solvent inside the container unit.

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, when recovering the solvent by distilling the waste solvent in the container, optimizing the discharge timing of the waste solvent remaining in the slurry state in the container to obtain a solvent recovery rate and It relates to a solvent recovery system and method capable of increasing device stability.

Diborane (diborane or diborane) is a compound composed of boron and hydrogen, having the 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 technologies for producing diborane include a method of synthesizing by reacting BF ₃ and LiH, a method of using BCl ₃ and LiAlH ₄ , and a method of using NaBH ₄ and three raw materials (BF3, sulfuric acid, and I). It is becoming.

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. In order to prepare diborane (B ₂ H ₆ :diborane) in the reaction unit, an ether-based solvent (eg, 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, while increasing the recovery efficiency of the organic solvent, while optimizing the discharge timing of the waste solvent in the slurry state remaining inside the container, the purpose is to provide a solvent recovery system and method to be

In one embodiment of the present invention, a storage unit for storing liquid waste solvent introduced through a liquid inlet and evaporating the solvent, a gas outlet formed in an upper region of the storage unit and discharging gas evaporated from the storage unit; A recovered solvent storage unit in which the gas discharged through the gas outlet is cooled and stored in a liquid state, a liquid outlet formed in the lower region of the container unit and discharging the waste solvent remaining in the container unit, and a waste solvent storage unit in the container unit. Providing a solvent recovery system when producing diborane, including an agitator for stirring the solvent, a control unit for controlling the opening and closing of the liquid outlet, and a control unit for controlling the operation of the control unit according to the concentration of the waste solvent inside the container unit can do.

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 a waste solvent concentration according to a value detected by the torque sensing unit.

The stirring device may include a central axis disposed vertically at the center of the container unit, a first rotation unit disposed below the central axis, and a second rotation unit disposed at the center of the central axis.

The solvent recovery system further includes a first level sensor disposed in the container unit to measure the amount of waste solvent in the container unit, and a second level sensor disposed in the recovered solvent storage unit to measure the volume of the recovered solvent. And, the control unit may be characterized in that the concentration of the waste solvent is calculated by calculating the solvent recovery rate from the measured amounts of the first level sensor and the second level sensor.

The solvent recovery system may be characterized in that the control unit opens the control unit when the solvent recovery rate is 55% to 60%.

In another embodiment of the present invention, after the diborane synthesis process introduced into the storage unit through the liquid inlet, distilling the liquid waste solvent to evaporate the solvent, detecting the concentration of the waste solvent present in the storage unit, and When the concentration of the waste solvent in the storage unit exceeds a predetermined concentration, a method for recovering the solvent in diborane production may be provided, comprising discharging the waste solvent in the storage unit to the outside.

In the 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 optimizing the discharge timing of waste solvent in a slurry state remaining in a container while increasing the recovery efficiency of the organic solvent in the diborane manufacturing 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 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 first chamber 101, an ether-based solvent (eg, diglyme) and NaBH ₄ powder may be 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 first chamber 101 . To prepare diborane (B ₂ H ₆ ), a mixed solution may be generated by dissolving NaBH ₄ powder in diglyme in a first chamber at room temperature (25° C.). In the first chamber 101, NaBH ₄ may be dissolved in a 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 mixed in this way may be injected into the second chamber 102 . Before the mixed solution is injected into the second chamber 102, it may be purged with an inert gas to maintain a pressure lower than that of the first chamber 101 after removing impurities. In addition, the second chamber 102 may be located at a lower position than the first chamber 101 so that the mixed solution is injected using gravity. The mixed solution may be transferred from the first chamber 101 to the second chamber 102 through a pipe connected between the first chamber 101 and the second chamber 102 and valve control. In the second 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 second 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, although the first chamber 101 and the second chamber 102 are shown and described separately, 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 first chamber and the second chamber are separately installed, the amount of NaBH ₄ and BF ₃ gas injected into the second chamber 102 is adjusted to mix and react in the second chamber. can proceed continuously. In addition, while the diborane gas is being synthesized in the second chamber, a process of generating a mixed solution in the first chamber and supplying the mixed solution to the second 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 second 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 second 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 first chamber. You can pass it back to (101).

The solvent recovery system 100 according to the present embodiment includes a storage unit 110, a gas outlet 120, a recovered solvent storage unit 130, a liquid outlet 140, a stirring device 150, a control unit ( 160) and a controller 170.

The storage unit 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 container part 110, impurities remaining after NaBH ₄ and BF ₃ react are dissolved in the diglyme solvent. The storage unit 110 may be equipped with a means for heating the waste solvent in order to recover pure diglyme solvent from the waste solvent containing impurities. The pure diglyme solvent may be evaporated into a gaseous state by heating the waste solvent in the container part 110 through 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, the container unit is configured as a double container, hot oil is supplied between the inner container and the outer container, and the pressure inside the inner container is maintained at 50 to 100 torr so that the boiling point at atmospheric pressure is reached. 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 gas outlet 120 is a passage for extracting the diglyme solvent evaporated from the storage unit into the recovery solvent storage unit 130. A valve may be additionally formed at the gas outlet 120 to adjust the extraction amount of the diglyme solvent of the gas component extracted from the container part 110 .

The recovered solvent storage unit 130 may cool the diglyme solvent of a gaseous component evaporated in the storage unit 110 and store it as a diglyme solvent in a liquid state. The recovered solvent storage unit 130 includes a cold trap for cooling the diglyme solvent injected in a gaseous state, a storage unit for storing the cooled diglyme solution, and a pump for transferring the stored diglyme solution to the first chamber. can include

The liquid outlet 140 is a passage for evaporating the solvent through a distillation process in the container part 110 and discharging the remaining slurry-state waste solvent. The liquid outlet 140 is disposed at the lower end of the container part 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 150 may increase evaporation efficiency during the distillation process by stirring the waste solvent in the container part. The stirring device 150 may be implemented in the form of a rotating blade, and a motor for rotating the stirring device may be mounted.

The control unit 160 is disposed in the liquid outlet 140 to control opening and closing of the liquid outlet. A discharge timing of the waste solvent in the storage unit may be determined by the opening and closing operation of the control unit.

The control unit 170 may control the opening and closing operation of the control unit according to the concentration of the waste solvent inside the container unit. The control unit 170 may detect the concentration of the waste solvent inside the container unit in various ways, and the control unit 160 is closed until the concentration of the waste solvent inside the container unit reaches a predetermined concentration. The distillation process is performed inside, and when the concentration of the waste solvent is detected to be higher than a certain concentration, the control unit 160 may be opened to discharge the waste solvent in a slurry state.

The longer the process of separating diglyme from the waste solvent by the distillation process in the container part increases, that is, the higher the powder concentration in the waste solvent, the higher the amount of diglyme extraction. However, if the powder concentration in the waste solvent is too high, the flowability of the slurry may be reduced, causing problems such as clogging of the liquid outlet 140 for discharging the waste solvent or remaining of the slurry in a solid state in the container. Therefore, it is important to carry out the distillation process within the storage unit for a period of time capable of maximizing the recovery rate of diglyme while maintaining the slurry concentration to such an extent that the liquid outlet 140 is not clogged or remaining inside the storage unit. In the solvent recovery system according to the present embodiment, the control unit 170 detects the concentration of the waste solvent in the storage unit, and when the concentration set therein is reached, the control unit 160 may be opened to discharge the waste solvent. Therefore, it is possible to increase the recovery rate of diglyme from the waste solvent and increase the utilization of process equipment.

2 is a block diagram of a solvent recovery system when producing diborane according to another embodiment of the present invention.

Referring to FIG. 2 , the solvent recovery system 200 according to the present embodiment includes a storage unit 210, a gas outlet 220, a recovered solvent storage unit 230, a liquid outlet 240, and a stirring device ( 250), a controller 260, and a controller 270.

The storage unit 210 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 container part 210, impurities remaining after NaBH ₄ and BF ₃ react are dissolved in the diglyme solvent. A means for heating the waste solvent in order to recover pure diglyme solvent from the waste solvent containing impurities may be installed in the container part 210 . The waste solvent may be heated in the storage unit 210 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 inside the container part 210 may be maintained. In order to maintain the degree of vacuum, a constant flow rate of nitrogen may be supplied to the container part 210 . 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 gas outlet 220 is a passage through which the gaseous diglyme solvent evaporated from the storage unit is extracted into the recovery solvent storage unit 230 . A valve may be additionally formed at the gas outlet 220 to adjust the extraction amount of the diglyme solvent of the gas component extracted from the container part 210 .

The recovered solvent storage unit 230 may cool the diglyme solvent of a gaseous component evaporated in the container unit 210 and store it as a diglyme solvent in a liquid state. The recovered solvent storage unit 230 includes a cold trap for cooling the diglyme solvent injected in a gaseous state, a storage unit for storing the cooled diglyme solution, and a pump for transferring the stored diglyme solution to the first chamber. can include

The liquid outlet 240 is a passage for evaporating the solvent through a distillation process in the container part 130 and discharging the remaining slurry-state waste solvent. The liquid outlet 240 is disposed at the lower end of the container part 230 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 control unit 260 is disposed in the liquid outlet 240 to control opening and closing of the liquid outlet. A discharge timing of the waste solvent in the storage unit may be determined by the opening and closing operation of the control unit.

The control unit 270 may control the opening and closing operation of the control unit according to the concentration of the waste solvent inside the container unit. The control unit 270 may detect the concentration of the waste solvent inside the container unit in various ways, and the control unit 260 is closed until the concentration of the waste solvent inside the container unit reaches a predetermined concentration. The distillation process is performed inside, and when the concentration of the waste solvent is detected to be higher than a certain concentration, the controller 260 may be opened to discharge the waste solvent in a slurry state.

In this embodiment, the stirring device 250 may be disposed inside the container part 210 . The stirring device 250 may increase evaporation efficiency during the distillation process by stirring the waste solvent in the container unit. In this embodiment, the stirring device 250 includes a central axis 251 disposed in the vertical direction at the center of the container unit, a first rotation unit 252 disposed below the central axis, and a first rotation unit disposed above the first rotation unit. 2 may include a rotating part 253. In addition, a motor 254 may be connected to the outside of the container to rotate the central axis. The rotation of the motor rotates the first rotation unit and the second rotation unit inside the container unit 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 200 according to the present embodiment may further include a torque sensor 290 that detects torque of the agitator 250 . The torque sensor 290 may be a sensor that measures the RPM of the motor 254 that rotates the stirring device. The stirring device 250 may be rotated to stir the waste solvent inside the container part. As the distillation process inside the container part progresses, the concentration of the powder in the waste solvent increases, so the torque applied to the stirring device further increases. Accordingly, the RPM of the motor rotating the stirring device is further increased. The torque sensing unit 290 detects the RPM of the motor for rotating the stirring device, and when the RPM increases, it can detect that the concentration of the waste solvent inside the container unit has increased.

The control unit 270 recognizes that the concentration of the waste solvent has reached a certain concentration or higher when the RPM of the motor sensed by the torque sensor 290 is detected to be higher than a predetermined value, and opens the control unit 260 to control the container unit. Waste solvent inside can be discharged.

For example, the powder density of the waste solvent at the time the waste solvent is injected into the container unit may be about 5%. During the distillation process in the container part, 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 stirring device and the RPM value of the motor when the powder density of the waste solvent reaches about 10 to 20% are pre-entered into the control unit, the powder of the waste solvent in the container unit is determined by the RPM value of the motor detected by the torque sensing unit. 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 storage unit through the liquid outlet.

3 is a block diagram of a solvent recovery system when producing diborane according to another embodiment of the present invention.

Referring to FIG. 3 , the solvent recovery system 300 according to the present embodiment includes a storage unit 310, a gas outlet 320, a recovered solvent storage unit 330, a liquid outlet 340, and a stirring device ( 350), a control unit 360, a control unit 370, and a first level sensor 381 and a second level sensor 382 may be included.

The storage unit 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 container part 310, impurities remaining after NaBH4 and BF3 react are dissolved in the diglyme solvent. A means for heating the waste solvent in order to recover pure diglyme solvent from the waste solvent containing impurities may be installed in the container part 310 . The waste solvent may be heated in the storage unit 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 inside the container part 310 may be maintained. In order to maintain the degree of vacuum, a constant flow rate of nitrogen may be supplied to the container part 310 . 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 gas outlet 320 is a passage for extracting the diglyme solvent evaporated from the container part to the recovery solvent storage part 330. A valve may be additionally formed at the gas outlet 320 to adjust the extraction amount of the diglyme solvent of the gas component extracted from the container part 310 .

The recovered solvent storage unit 330 may cool the diglyme solvent of a gaseous component evaporated in the container unit 310 and store it as a diglyme solvent in a liquid state. The recovered solvent storage unit 330 includes a cold trap for cooling the diglyme solvent injected in a gaseous state, a storage unit for storing the cooled diglyme solution, and a pump for transferring the stored diglyme solution to the first chamber. can include

The liquid outlet 340 is a passage for evaporating the solvent through the distillation process in the container part 330 and discharging the remaining slurry waste solvent. The liquid outlet 340 is disposed at the lower end of the container part 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 350 may increase evaporation efficiency during the distillation process by stirring the waste solvent in the container part. The stirring device 350 may be implemented in the form of a rotating blade, and a motor for rotating the stirring device may be mounted.

The control unit 360 is disposed in the liquid outlet 340 to control opening and closing of the liquid outlet 340 . A discharge timing of the waste solvent in the storage unit may be determined by the opening and closing operation of the control unit.

The control unit 370 may control the opening and closing operation of the control unit according to the concentration of the waste solvent inside the container unit. The control unit 370 may detect the concentration of the waste solvent inside the container unit in various ways, and the control unit 360 is closed until the concentration of the waste solvent inside the container unit reaches a predetermined concentration. The distillation process is performed inside, and when the concentration of the waste solvent is detected to be higher than a certain concentration, the controller 360 may be opened to discharge the waste solvent in a slurry state.

In this embodiment, the stirring device 350 may be disposed inside the container part 310 . The stirring device 350 may increase evaporation efficiency during the distillation process by stirring the waste solvent in the container unit. In the present embodiment, the stirring device 350 includes a central shaft 351 disposed vertically at the center of the container unit, a first rotation unit 352 disposed below the central shaft, and a second rotation unit disposed at the center of the central shaft. (353). In addition, a motor 354 may be connected to the outside of the container to rotate the central axis. The rotation of the motor rotates the first rotation unit and the second rotation unit inside the container unit 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 include a first level sensor 381 and a second level sensor 382 . The first level sensor 381 may measure the capacity of the waste solvent injected into the storage unit 310, and the second level sensor 382 may measure the capacity of the solvent stored in the recovered solvent storage unit 330. can be measured When the solvent recovery system according to the present embodiment is operated, the waste solvent in the container unit 310 is evaporated by the distillation process, so that the capacity of the waste solvent in the container unit decreases over time. The first level sensor can detect that the capacity of the waste solvent inside the container is reduced. The diglyme solvent evaporated in the storage unit may be stored in the recovery solvent storage unit 330 in a liquid state. Over time, the capacity of diglyme stored in the recovery solvent storage unit 330 increases. The second level sensor may detect the increase of the diglyme solvent in the recovered solvent storage unit.

In this embodiment, the controller 370 may detect the amount of waste solvent and the amount of recovered diglyme solvent from the first level sensor 381 and the second level sensor 382 . By calculating the amount of the detected waste solvent and the amount of the recovered diglyme solvent, it is possible to calculate the solvent recovery rate and the powder density of the waste solvent currently remaining in the container. 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 can 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 370 recognizes that the concentration of the waste solvent in the storage unit has reached a predetermined concentration or higher when the solvent recovery rate reaches a predetermined value, and opens the control unit 360 to remove the waste solvent inside the storage unit. can be ejected.

For example, the powder density of the waste solvent at the time the waste solvent is injected into the container unit may be about 5%. During the distillation process in the container part, 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 storage unit can be discharged through the liquid outlet.

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

Referring to FIG. 4 , the solvent recovery method 400 in producing diborane according to the present embodiment includes evaporating the solvent (401), detecting the concentration of the waste solvent (402), and discharging the waste solvent to the outside. Step 403 may be included.

In the step 401 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. 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 402 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 403 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.

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: container unit 130: recovery solvent storage unit
150: stirring device 160: control unit
170: control unit

Claims (7)

A storage unit for storing liquid waste solvent introduced through the liquid inlet and evaporating the solvent;
a gas outlet formed in an upper region of the container part and discharging gas evaporated from the container part;
a recovery solvent storage unit in which the gas discharged through the gas outlet is cooled and stored in a liquid state;
a liquid outlet formed in a lower region of the container part and discharging the waste solvent remaining in the container part;
A stirring device for stirring the waste solvent in the container portion;
a controller controlling opening and closing of the liquid outlet; and
Control unit for controlling the operation of the control unit according to the concentration of the waste solvent inside the container unit
Solvent recovery system in the manufacture of diborane comprising a.
According to claim 1,
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 1,
The stirring device may include a central axis disposed vertically at the center of the container part;
a first rotation unit disposed below the central axis;
A solvent recovery system for producing diborane, characterized in that it comprises a second rotation part disposed at the center of the central axis.
According to claim 1,
a first level sensor disposed in the container part to measure the capacity of the waste solvent in the container part; and
Further comprising a second level sensor disposed in the recovered solvent storage unit to measure the amount 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.
According to claim 4,
When the solvent recovery rate is 55% to 60%, the solvent recovery system for diborane production, characterized in that the control unit opens the control unit.
evaporating the solvent by distilling the liquid waste solvent generated after the diborane synthesis process introduced into the container through the liquid inlet;
detecting the concentration of the waste solvent present in the container part; and
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
Solvent recovery method in diborane production comprising a.
According to claim 6,
The 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.

Images