KR20200088600A - Method for generating high purity diborane using BF3 simultaneous reaction process and apparatus for the same - Google Patents

Abstract

The present invention relates to a method for preparing high-purity diborane using a BF_3 simultaneous reaction process, and an apparatus therefor. The method for preparing diborane includes the steps of: 1) dissolving sodium borohydide (NaBH_4) powder in an ether solvent at room temperature in a powder reactor to form a mixed solution; 2) conveying the mixed solution to a main reactor by using gravity and differential pressure, injecting boron trifluoride (BF_3) gas to the main reactor at a predetermined rate to allow its reaction with the mixed solution, thereby producing a first reaction gas including diborane (B_2H_6) gas mixed with impurities; and 3) purifying the first reaction gas by removing the impurities therefrom through a purification process.

Description

Method for generating high purity diborane using the simultaneous reaction process of boron trifluoride and its manufacturing apparatus{Method for generating high purity diborane using BF3 simultaneous reaction process and apparatus for the same}

The present invention relates to a high-purity diborane production method using the BF ₃ co-reaction process and a manufacturing apparatus thereof, and more specifically, to minimize the risk of leaking toxic substances, reduce manufacturing costs, and manufacture with high purity. The present invention relates to a high-purity diborane production method using a BF ₃ co-reaction process capable of producing diborane that can be used in semiconductor processes or other precision industrial processes, and a manufacturing apparatus thereof.

Diborane (diborane, diborane or diborane) is a compound of boron and hydrogen having the formula B ₂ H ₆ . At room temperature, it is a colorless gas with a sweet aroma. Diborane is easily mixed with air, so it is easy to make an explosive mixture. It has the characteristics of spontaneous ignition when it comes in contact with humid air, and is widely used as a rocket propellant. In addition, diborane gas is used as a P-type dopant for semiconductor equipment, and is widely used in the electronics industry and its applications.

Conventional techniques for producing diborane are a method of synthesizing 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, I), etc. It is being introduced. Each reaction formula is as follows.

1) 8BF ₃ + 6LiH → 2B ₂ H ₆ + 6LiBF ₄

2) 4BCl ₃ + 3 LiAlH ₄ → 2B ₂ H ₆ + 3LiAlCl ₃

3) 4BF ₃ + 3NaBH ₄ → 2B ₂ H ₆ +3NaBF ₄

_{^{4) 2BH 4 - + 2H +}} ( sulfuric acid) → 2H ₂ + B ₂ H ₆

5) 4NaBH ₄ + I ₂ → 2NaI + H ₂ + B ₂ H ₆

However, since the conventional techniques related to diborane production focus on low-purity diborane production, it is difficult to apply to semiconductor processes that require high purity, and diborane gas contains many impurities such as hydrogen and higher borane. Since it is mixed, there is a problem in that it requires a considerable investment cost to prepare a refining facility necessary for manufacturing with high purity, and the cost for manufacturing high purity diborane is expensive.

In addition, despite the fact that the BF ₃ -adduct intermediate produced as an intermediate for the production of diborane is known as a very unstable and dangerous material, there is a disadvantage in that a considerable cost to safety is handled as a separate process.

Republic of Korea Registered Patent Publication No. 10-0731836 (2007.06.18.)

Accordingly, an object of the present invention is to provide a high purity diborane production method and a manufacturing apparatus using a BF ₃ simultaneous reaction process that can overcome the above-described conventional problems.

It is another object of the present invention minimizes the steps and reduce the production cost and improve efficiency, manufacturing method of high purity diborane lane with safety the BF ₃ simultaneous reaction process and a continuous process that can be fundamentally prevented, and the manufacturing apparatus To provide.

In accordance with an embodiment of the present invention for achieving some of the above technical problems, the method for manufacturing diborane according to the present invention dissolves NaBH ₄ (Sodium Borohydride) powder in an ether-based solvent in a powder reactor at room temperature. A first step of generating a mixed solution; The mixed solution is transferred to the main reactor using gravity and differential pressure, and BF ₃ (Boron trifluoride) gas is injected into the main reactor at a constant rate to react with the mixed solution to impurity and diborane (B ₂ H ₆ : diborane) a second step of generating a first reaction gas mixed with gas; A third step of purifying the first reaction gas by removing impurities through a purification process is provided.

In the refining process, the first reaction gas is passed through a freezing trap of -60 to -80°C, so that BF ₃ (Boron trifluoride) reacts with the ether-based solvent to include impurities and ether impurities. Generating a second reaction gas by removing the first impurities by freezing or liquefying; The second reaction gas is introduced into an adsorption tower, and a second impurity containing high-order borane, carbon dioxide (CO ₂ ), water vapor (H ₂ O), and methane gas (CH ₄ ) is removed using an adsorbent to remove the third impurity. Generating a reaction gas; The third reaction gas is introduced into a distillation column to perform a distillation process using a boiling point difference to remove a third impurity containing hydrogen gas (H ₂ ) and methane gas (CH ₄ ) to remove high-purity diborane of 99.99% or more ( diborane) may be provided.

The distillation process includes a transfer step of transferring the third reaction gas to a distillation column; By maintaining the inside of the distillation column at a temperature of -100 to -140°C using a refrigerant, diborane (B ₂ H ₆ :diborane) gas is liquefied and moves to the bottom of the distillation column by gravity, and the third impurity is A first distillation step of maintaining the vaporized state to collect at the top of the distillation column and removing it; A re-transfer step of vaporizing liquefied diborane using a vaporizer and transferring the vaporized diborane (B ₂ H ₆ :diborane) gas to the distillation column; A second distillation step of removing the fine impurity gas not removed through the first distillation step may be provided by maintaining the inside of the distillation column at a temperature of -100 to -140°C using a refrigerant.

When the first reaction gas is generated in the main reactor in the second step, the powder reactor dissolves NaBH ₄ (Sodium Borohydride) powder in an ether-based solvent to perform a process of generating a mixed solution to perform the main reaction. Reactor.

The ether-based solvent is triglyme (Triethylene glycol dimethyl ether; C ₈ H ₁₈ O ₄ ) Or tetraglyme (Tetraethylene glycol dimethyl ether; C ₁₀ H ₂₂ O ₅ ).

In the second step, the main reactor may be maintained at a temperature of 5 to 10° C. to minimize vaporization of impurities.

In the second step, BF ₃ (Boron trifluoride) gas may be slowly injected into the main reactor at a rate of 3 to 4 kg/hour.

In the adsorption tower, zeolite 4A (MS (Molecular sieve) 4A), activated carbon, and zeolite 13X (MS 13X) may be sequentially filled from bottom to top in a volume ratio of 1:1:1 as an adsorbent.

The adsorption tower may perform low temperature adsorption with a reaction temperature of -30 to -20°C during the adsorption process, and high temperature regeneration with a reaction temperature of 200 to 350°C during the regeneration process.

The vaporizer in the re-transfer step may be maintained at a reaction temperature of 5 ~ 10 ℃ to minimize the vaporization of impurities.

After the second distillation step, a storage step of storing the diborane in which impurities are removed in a liquefied state in a storage tank may be provided.

The first to third steps may be performed in a pressure atmosphere lower than atmospheric pressure.

According to another embodiment of the present invention for achieving some of the above technical problems, the apparatus for manufacturing diborane according to the present invention dissolves NaBH ₄ (Sodium Borohydride) powder in an ether-based solvent at room temperature to prepare a mixed solution. A powder reactor to be produced; The mixed solution is transferred using gravity and differential pressure, and BF ₃ (Boron trifluoride) gas is injected into the transferred mixed solution at a constant rate to react with the mixed solution to impurity and diborane (B ₂ H ₆ :diborane) A main reactor for generating a first reaction gas mixed with gas; And a purification unit for purifying the first reaction gas by removing impurities through a purification process.

The purification unit, the temperature of -60 ~ -80 ℃ is maintained, while the first reaction gas is passed, BF ₃ (Boron trifluoride) is a first including impurities and ether impurities formed by reacting with the ether-based solvent A freezing trap that removes secondary impurities by freezing or liquefying to generate a second reaction gas; By introducing the second reaction gas, a third reaction gas is removed by removing secondary impurities including high-order borane, carbon dioxide (CO ₂ ), water vapor (H ₂ O), and methane gas (CH ₄ ) using an adsorbent. Adsorption module for generating; A distillation column that generates diborane by removing the third impurity containing hydrogen gas (H ₂ ) and methane gas (CH ₄ ) by performing the distillation process using the boiling point difference by introducing the third reaction gas It can be provided.

A vaporizer for vaporizing the liquefied diborane discharged from the distillation column to perform the distillation process again in the distillation column may be further provided.

The adsorption module includes two adsorption towers alternately performing adsorption and regeneration processes, and a valve box for controlling opening and closing of valves connected to the two adsorption towers, and the adsorption tower is a zeolite 4A (MS) (Molecular sieve) 4A), activated carbon and zeolite 13X (MS 13X) may have a structure that is sequentially filled from bottom to top in a volume ratio of 1:1:1.

The adsorption tower may perform low temperature adsorption with a reaction temperature of -30 to -20 °C during the adsorption process, and high temperature regeneration with a reaction temperature of 200 to 350 °C during the regeneration process.

The linear velocity of the second reaction gas passing through the adsorbent may be controlled through the valve box at 0.01 to 1 Nm/sec.

In the main reactor, a flow meter or mass flow controller (MFC) for uniformly injecting BF ₃ (Boron trifluoride) gas into the main reactor at a rate of 3 to 4 kg/hour may be provided.

L (length) / D (Depth) of the distillation column may be 10 to 15.

A storage tank for liquefying and storing diborane from which impurities have been removed through the distillation column; A charging unit for filling the cylinder with diborane stored in the storage tank may be further provided.

According to the present invention, it is possible to minimize the process, and the manufacturing efficiency and cost can be drastically reduced by the BF ₃ simultaneous reaction process and the continuous process, and the entire manufacturing/purification process is less than atmospheric pressure (below 0 bar _g ) and vacuum It has the effect of maximizing safety by completely removing the risk factors caused by internal ignition and air pollution. In addition, high-purity diborane (B ₂ H ₆ (99.99% or more)) gas production is possible and has an advantage that can be applied to various industrial processes as well as semiconductor processes.

1 is a schematic block diagram of a diborane manufacturing apparatus for manufacturing a high purity diborane (B ₂ H ₆ :diborane) according to an embodiment of the present invention,
FIG. 2 is a concrete block diagram of FIG. 1,
Figure 3 is a table showing the production conditions and production rates and recovery rates according to the respective examples and control examples.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, without intention other than to provide a thorough understanding of the present invention to those of ordinary skill in the art.

1 is a schematic block diagram of a diborane manufacturing apparatus for manufacturing high purity diborane (B ₂ H ₆ :diborane) according to an embodiment of the present invention, and FIG. 2 is a concrete block diagram of FIG. 1.

1 and 2, a diborane (B ₂ H ₆ :diborane) manufacturing apparatus according to an embodiment of the present invention includes a reaction unit 100 and a purification unit 200. In addition, a storage unit 300 may be provided.

In the present invention, NaBH ₄ (Sodium Borohydride) and BF ₃ (Boron trifluoride) are reacted to prepare diborane (B ₂ H ₆ :diborane) containing impurities, and purified by adsorption and distillation to obtain high purity diborane (B ₂ H ₆ : diborane).

In the reaction unit 100, in order to prepare diborane (B ₂ H ₆ :diborane), 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 , etc.), through which an intermediate, which is an adduct material of BF ₃ and ether, was made, and this process was configured to proceed simultaneously (or continuously) at once.

In other words, NaBH ₄ is dissolved in an ether-based solvent and BF ₃ is injected to form an intermediate, which is an adduct material of BF ₃ and ether, and at the same time, diborane (B ₂ H ₆ ) is produced. I am using it. In this case, by supplying BF ₃ slowly diborane lane (B ₂ H ₆₎ diborane lane (B ₂ H ₆₎ as a step-by-step to produce an NaBH ₄ solution in the other reactor (i.e. powder reactor 110) during manufacture of the prepared Is done.

In summary, it is shown in the reaction scheme below.

[Reaction formula]

4BF ₃ (BF _3ㆍ ether) + 3NaBH ₄ → 2B ₂ H ₆ + 3NaBF ₄ (proceeds in the presence of ether-based solvent)

The production of diborane (B ₂ H ₆ ) through the reaction scheme is characterized in that the reaction temperature is 0-40° C., and the reaction pressure is performed at atmospheric pressure or lower (0--1 barg).

When diborane (B ₂ H ₆ ) is produced through the reaction unit 100, there is no process to remove impurities in the middle because the reaction proceeds simultaneously and continuously at one time, unlike the prior art. Therefore, the proportion of impurities (higher borane, methane, CO ₂ , Hydrocarbon, diethylene glycol monomethylether, alcohols, etc.) generated by the decomposition of ether-based solvents may be rather high. However, the reaction is continuously performed at one time, and the process is simple and it is safe because the intermediates are not separately handled. As shown in FIG. 3, the conversion rate (Control 1, about 50.9% → Example 1, 74.1%) was significantly increased. Able to know. In this case, impurities generated are removed in the purification unit 200 by an adsorption process (removal of higher borane, CO _2, etc.) and a distillation process (removal of methane, hydrogen, etc.), which are purification processes.

The purification unit 200 removes impurities such as higher borane, carbon dioxide (CO ₂ ), methane, and hydrogen through a purification process, an adsorption process, and a distillation process, thereby purifying high-purity diborane (B ₂ H ₆ ). To manufacture.

The storage unit 300 is provided with a storage tank and a charging unit, to store the diborane (B ₂ H ₆ ) manufactured in high purity and to be charged into the filling cylinder to be used for various purposes or mixed with various gases. .

2, the reaction unit 100 includes a powder (powder) reactor 110 and the main reactor 120.

The volume of the powder reactor 110 is 300L, the volume of the main reactor 120 is 500L, and the inside may have a structure subjected to electropolishing. A mixer may be built in the powder reactor 110 and the main reactor 120 to mix the solution well.

In addition, the powder reactor 110 is further provided with a powder transfer pump (not shown), a liquid pump (not shown), etc. to stably supply NaBH ₄ and an ether-based solvent (eg, triglyme or tetraglyme). Can.

For diborane (B ₂ H ₆ ), NaBH ₄ (Sodium Borohydride) powder in the powder reactor 110 at room temperature (25° C.) is 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 , etc.) dissolved sufficiently (approximately 4-5 hours) to produce a mixed solution.

The solubility of NaBH _{4 in} the ether solvents triglyme and tetraglyme is known to be about 4 M at room temperature (25° C.), so it is controlled to dissolve in 5 M (preferably 4.5 to 3 M) at a slight excess at room temperature. Avoid problems such as valve clogging due to particles.

In the powder reactor 110, NaBH ₄ is properly dissolved in an ether-based solvent through a built-in mixer. At this time, the upper part of the raw material in the powder reactor 110 removes impurities with an inert gas such as nitrogen and uses a vacuum pump to make the pressure lower than atmospheric pressure (0 atm _g or less as a gauge pressure).

Before the mixed solution is injected from the powder reactor 110, the main reactor 120 is purged with an inert gas to remove impurities and maintain a lower pressure than the powder reactor 110. Also, the main reactor 120 is positioned at a lower position than the powder reactor 110 so that gravity can be used.

Accordingly, the mixed solution is the main in the powder reactor 110 through gravity and differential pressure through the control of the pipe line (L1) and valve (V1) connected between the powder reactor 110 and the main reactor 120 It will be transferred to the reactor 120.

In the main reactor 120, BF ₃ (Boron trifluoride) gas is injected at a constant rate to react with the mixed solution to form a first reaction gas in which impurities and diborane (B ₂ H ₆ :diborane) gas are mixed. Will be created.

In the main reactor 120, BF ₃ is directly injected into the mixed solution to react. It is preferable to inject BF ₃ into the gas phase in a slight excess of the reaction equivalent ratio using a flow meter or a mass flow controller (MFC). The BF ₃ is slowly injected (eg, injected at a rate of 3 to 4 kg/hour) to induce the synthesis of an ether-based solvent and an adduct intermediate. For example, if the total injection amount of BF ₃ is 24.4 kg, it is divided into 7 hours or more and injected evenly.

When the reaction is performed while the main reactor 120 is maintained in a vacuum state, the main reactor 120 in a vacuum state contains some impurities, but diborane (B ₂ H ₆ ) gas is mainly generated and filled. . At this time, the temperature of the main reactor 120 is maintained at 5 to 10 degrees to minimize the vaporization of impurities. Here, the mixed gas in which the impurity and diborane (B ₂ H ₆ ) gas are mixed will be referred to as a first reaction gas.

While generating the first reaction gas in the main reactor 120, the powder reactor 110 continuously performs the process of generating the mixed solution and providing it to the main reactor 120. At this time, the powder reactor 110 may perform a process of generating the mixed solution after performing an impurity removal process using an inert gas such as nitrogen. That is, when a mixed solution is generated and provided to the main reactor 120, a process of generating the mixed solution is performed after the impurity removal process is performed.

On the other hand, when the reaction for generating the first reaction gas is completed, the main reactor 120 vents the waste solution and transfers it to the waste solution storage tank (not shown), and the first reaction gas is a purification unit 200 ).

Accordingly, the first reaction gas is continuously generated through the powder reactor 110 and the main reactor 120 and sent to the purification unit 200, and the diborane purified in the purification unit 220 is a storage unit ( 300).

Since the first reaction gas contains many impurities such as hydrogen and higher borane, purification for the first reaction gas is essential for high purity.

The purification process is performed through the purification unit 200.

The purification unit 200 includes a freezing trap 210, an adsorption module 220, and a distillation column 240, as shown in FIG. Additionally, a vaporizer 250 may be further provided.

The frozen trap 210 is maintained at a temperature of -60 to -80°C, and while the first reaction gas passes, impurities and ether impurities formed by BF ₃ (Boron trifluoride) reacting with the ether-based solvent The second impurity gas is generated by removing the first impurity containing froze or liquefy.

The adsorption module 220 is introduced into the second reaction gas, and a second impurity including high order borane, carbon dioxide (CO ₂ ), water vapor (H ₂ O), and methane gas (CH ₄ ) using an adsorbent. Is removed to generate a third reaction gas. Here, a higher borane may mean a material having more boron (B) bonds (3 or more) than diborane.

The adsorption module 220, the valve box for controlling the opening and closing of the valves connected to the two adsorption towers (220a, 220b) and the two adsorption towers (220a, 220b) alternately performing the adsorption process and the regeneration process (222a, 222b). In addition, the adsorption towers 220a and 220b have a structure in which zeolite 4A (MS (Molecular sieve) 4A), activated carbon, and zeolite 13X (MS 13X) are sequentially filled from bottom to top with a volume ratio of 1:1:1 as an adsorbent. Can have The adsorption module 220 alternately uses the first adsorption tower 220a and the second adsorption tower 220b through valve opening and closing control of the valve boxes 222a and 222b. The volumes of the adsorption towers 220a and 220b may be provided as 50 L, respectively.

The adsorption towers 220a and 220b operate at high temperature regeneration and low temperature adsorption using heat medium oil operated at -40 to 400°C, or circulate refrigerant at -30 to -20°C for low temperature adsorption and nitrogen to the heater 224 It may be operated by heating to a high temperature regeneration (200 ~ 350 ℃). At this time, the refrigerant is separated so that the refrigerant does not vaporize due to high temperature. That is, in each of the adsorption towers 220a and 220b, during the adsorption process, the reaction temperature of the adsorption column is low-temperature adsorption to -30 to -20°C. It is possible to perform.

The distillation column 240 performs the first distillation process using the difference in boiling point by introducing the third reaction gas to remove the third impurity including hydrogen gas (H ₂ ) and methane gas (CH ₄ ), thereby A lane (diborane) is generated. A filling material may be provided inside the distillation column 240 so that gas and liquid are well met. In addition, the volume of the distillation column is 150L and the length-to-depth ratio (L(length)/D(Depth)) is set to 10 or more (preferably 10 to 15) to sufficiently distill.

The vaporizer 250 vaporizes the liquefied diborane discharged from the distillation column 240 to perform a second distillation process to perform the distillation process again in the distillation column 240.

Looking briefly at the purification process through the purification unit 200, first, the first reaction gas generated in the reaction unit 100 passes through the freezing trap 210. The refrigeration trap 210 is primarily formed by the impurities (ether) such as ether impurities and BF ₃ -adduct intermediate from the main reactor 120, and decomposed impurities (ethers such as short chains). It is filtered so that a second reaction gas is generated.

The second reaction gas is introduced into the valve box 222a through a pipe L3 connecting the refrigeration trap 210 and the valve box 222a. When the first adsorption tower 220a performs an adsorption process and the second adsorption tower 220b performs a regeneration process through the control of the valve boxes 222a and 222b, the second reaction gas is the first adsorption tower 220a. Flow through, and adsorber (higher borane) through adsorbent (activated carbon is filled with 1/3 of the volume ratio, MS (Molecular sieve) 4A is filled with 1/3, and the remaining 1/3 is filled with MS 13X). , It is possible to remove a significant amount of secondary impurities such as water vapor (H ₂ O), carbon dioxide (CO ₂ ), CH ₄ , and thus a third reaction gas is generated. At this time, the reaction temperature of the first adsorption tower 220a performing the adsorption process is maintained at -30 to -20°C, and a refrigerant may be used for this.

The valve boxes 222a and 222b may be adjusted so that the linear velocity of the second reaction gas passing through the adsorbent is about 0.01 to 1 Nm/sec.

In the case of the second adsorption tower 220b, a regeneration process is performed, and in this case, the reaction temperature is raised to 200 to 350° C. by heating an inert gas or using a heating medium. That is, when heat medium oil that can be used at -40 to 400°C is used or used independently, the refrigerant is vented so that it does not evaporate. When the regeneration process is completed, the adsorption tower is replaced so that the first adsorption tower 220a performs a regeneration process, and the second adsorption tower 220b performs an adsorption process, from the first adsorption tower 220a to the second adsorption tower 220b. Before replacement, impurities in the adsorption tower are finally removed through a vacuum process (0 to -1 bar _g below atmospheric pressure) using the vacuum pump 230.

The third reaction gas generated by removing the second impurities from the adsorption module 220 is transferred to the distillation column 240 along the pipe L4.

In the distillation column 240, a third such as H ₂ (bp: -252.76°C) and CH ₄ (bp: 161.5°C) is used by using a difference in boiling point (-92.5°C) of diborane (B ₂ H ₆ ). A first distillation process to remove secondary impurities is performed.

The inside of the distillation column 240 is maintained between -100 and -140°C by using a refrigerant (LN ₂ or refrigerants that can be cooled, etc.), and diborane (B ₂ H ₆ ) is liquefied to the bottom of the gravity direction. The third impurity, which falls and contains hydrogen gas (H ₂ ) and methane gas (CH ₄ ), vaporizes and collects at the top to discharge to the outside using a valve (V5).

Then, in the lower portion of the distillation column 240, the liquefied diborane (B ₂ H ₆ ) is vaporized again through the vaporizer 250 and sent to the distillation column 240 to perform a second distillation process to perform the distillation process again. By doing so, it is possible to remove fine impurities. At this time, the temperature of the vaporizer 250 is maintained at about 5 to 10° C., similar to the temperature of the reactor 120, and thus it is possible to suppress the generation of high-order borane due to high temperature. The second distillation process is performed in the same way as the first distillation process, and liquefied in a pipe (L6) connecting the distillation column 240 and the vaporizer 250 for performing the second distillation process. You can also install a pump.

Diborane in a liquefied state in which impurities are removed by performing the distillation process is transferred to and stored in the storage unit 300 through a pipe L6 connecting the distillation column 240 and the storage tank 310. And charged as needed.

The diborane in the gaseous state purified by removing impurities inside the distillation column 240 is the storage tank 310 through the upper pipe L5 connecting the distillation column 240 and the storage tank 310. Is transferred to.

The high purity diborane (B ₂ H ₆ ) purified and manufactured through the purification unit 200 is GC-DID (Gas Chromatograph-Discharge Ionization Detector), GC-MS (Mass Spectrometry), FT-IR (Fourier Transform Infrared) ), ICP-MS (Inductively Coupled Plasma), etc., it was confirmed that purification is possible to have a purity of 99.99% or more.

2, the storage unit 300 may include a storage tank 310 and a charging unit 330.

The storage tank 310 is for storing diborane from which impurities have been removed through the distillation column 240, and the filling unit 330 is used to store the diborane stored in the storage tank 310. To fill the cylinder.

The storage tank 310 stores high-purity diborane (B ₂ H ₆ ) at a liquefaction temperature (-100 to -140 degrees), and the volume may be provided as 250L. In addition, it is possible to maintain the temperature of the storage tank 310 by using a refrigerant (such as LN ₂ or refrigerants that can be cooled), and a vaporizer 320 may be provided. The vaporizer 320 was also maintained at about 5-10°C to suppress high-order borane formation.

The filling unit 330 is mixed with various gases or filled with a single gas for various uses.

The high-purity diborane production method using the BF ₃ co-reaction process having the above-described configuration and specific examples and control examples of the manufacturing apparatus are as follows.

[Example 1] (Use solvent: triglyme (Triethylene glycol dimethyl ether; C ₈ H ₁₈ O ₄ ))

9.86 kg of NaBH ₄ and 185 kg of Triglyme are introduced into the powder reactor 110 and dissolved sufficiently (preferably 4 to 5 hours) at room temperature with a mixer. After dissolving, the inside of the reactor 110 is sufficiently purged with nitrogen for external contamination and safety, and then maintained at a pressure lower than atmospheric pressure (preferably 500 mmHg _a or less). The main reactor 120 is sufficiently purged with nitrogen and then prepared to be maintained at a pressure lower than atmospheric pressure (preferably 200 mmHg _a or less). The mixed solution (NaBH ₄ solution) dissolved in the powder reactor 110 is transferred to the main reactor 120 due to a difference in gravity and pressure.

In the main reactor 120, a solution is mixed with a mixer, and BF ₃ is directly injected into the mixed solution through a tube that is permeated to the bottom of the container. The BF ₃ cylinder was used to inject 24.4 kg slowly for 7 hours by bubbling through the MFC. A large amount of Triglyme and BF ₃ meet in the main reactor 120 to form a BF ₃ -adduct intermediate, and as shown in the above-described reaction formula, a first reaction gas is generated and collected at the top of the main reactor 120. Here, since the reaction occurs rapidly, the temperature of the main reactor 120 is maintained at 10° C. lower than room temperature and raised to room temperature after the supply of BF ₃ is finished to collect partially dissolved diborane (B ₂ H ₆ ) for about an hour. . After the reaction is completed, the waste solution is vented to the waste solution storage tank. This process is repeated 1-5 times so that the distillation column 128 sufficiently undergoes distillation purification to collect the first reaction gas.

The refrigeration trap 210, which is the refining unit 200, is initially purged with nitrogen and managed at _a pressure lower than atmospheric pressure (200 mmHg _a or less), and removes first impurities from the first reaction gas. . The first impurity is a volatile impurity formed by decomposition of triglyme while the triglyme is vaporized in the main reactor 120 to pass to the next process together with the first reaction gas or to form a BF ₃ -adduct intermediate. It may include volatile impurities formed by side reactions. In order to liquefy and condense the primary impurities, the freezing trap 210 was operated at -80°C.

The adsorption module 220 is initially purged with nitrogen and managed at _a pressure lower than atmospheric pressure (200 mmHg _a or less). The adsorption module 220 is used to remove secondary impurities such as gaseous impurities CO ₂ , moisture (H ₂ O), and CH ₄ . When removing the second impurity, the adsorption tower temperature is maintained at -30 to -40 °C, preferably -35 °C to adsorb and remove at a low temperature. The tower is exchanged on a 7-hour basis, and when regenerated, it is maintained at 250°C for 4 hours and regenerated with nitrogen. High-temperature regeneration and low-temperature adsorption may be operated using heat medium oil operated at -40 to 400°C, or a low temperature adsorption may be performed by circulating a -35 degree refrigerant, and high temperature regeneration may be performed by heating nitrogen with a heater. At this time, the refrigerant is separated so that the refrigerant does not vaporize due to high temperature. Then, the valve boxes 222a and 222b were adjusted to make the adsorption tower linear velocity 0.01 to 1 Nm/sec in experience.

In the case of the distillation column 240, a refrigerant (engineered fluid such as LN ₂ or Novec 7200) capable of maintaining below -130 degrees flows separately to act as a condenser, and gaseous diborane introduced in the middle ( B ₂ H ₆ ) goes up and meets the condenser to go down to the liquid and down to the liquid to exchange.

The whole distillation column 240 maintains a vacuum housing or thorough heat to keep the low temperature well so that the temperature at the bottom is less than -100°C. It was designed so that the filling area was filled in the middle to increase the contact area. The material of the filling material is made of SUS 316L. In the lower portion of the distillation column 240, a space is maintained so that diborane (B ₂ H ₆ ) is liquefied and collected, and some diborane (B ₂ H ₆ ) has a structure that is vaporized and returned at around 10° C. through the vaporizer 250. . Through this, the third impurity of hydrogen gas (H ₂ ) and methane gas (CH ₄ ) is induced to collect impurities on the top of the distillation column 240. The third impurity (H ₂ ,CH _4, etc.) collected at the top is periodically vented through the vacuum pump 230 to maintain high purity.

In the case of the storage unit 300, the distillation column 240 can be directly connected to the filling unit 330, using gravity through the pipe L6 or using a low-temperature liquid pump (not shown), and debossing it to the storage tank 310. The lane B ₂ H ₆ is transported. In the same way as the distillation column, the upper portion of the storage tank 310 is maintained at -130°C or lower, thereby maintaining heat so that the entire storage tank is less than -100°C. In the storage tank, high-purity diborane (B ₂ H ₆ ) is connected to the filling unit 330 and mixed with various gases to make a product.

The diborane (B ₂ H ₆ ) produced in this way has a purity of 99.99% or higher and a recovery rate of 74.1%. It is suitable for ultra-fine processes such as semiconductors, and can reduce production and safety costs with the BF ₃ simultaneous reaction process and vacuum system. .

[Example 2] (Use solvent: Tetraglyme (Tetraethylene glycol dimethyl ether; C ₁₀ H ₂₂ O ₅ ))

The conditions were the same as in Example 1, and the production was performed using 230.7 kg of Tetraglyme. The high-purity diborane (B ₂ H ₆ ) prepared according to Example 2 was prepared with a purity of 99.99%, and the recovery rate was 70.5%.

[Control Example 1] (Used solvent: Diglyme (Diethylene glycol dimethyl ether, C ₆ H ₁₄ O ₃ ))

The same as in Example 1, but using Diglyme as a solvent, a method of separately generating the mixed solution in each of the powder reactor 110 and the main reactor 120 was used. That is, in the powder reactor 110, a mixed solution is prepared, and the BF ₃ -adduct intermediate is continuously formed in the main reactor 120, and instead of the BF ₃ simultaneous reaction process and the continuous process in which the first reaction gas is generated. In, a method of producing a mixed solution in the powder reactor 110 and producing a first reaction gas, and also producing a mixed solution in the main reactor 120 and producing a first reaction gas were used.

In the powder reactor 110, 9.86 kg of NaBH _{4 and} 99.9 kg of diglyme were mixed, but it was not melted at room temperature, and the temperature was raised to 35 degrees from the outside, but some did not melt. The main reactor 120) was slowly supplied with 24.4 kg of BF ₃ to Diglyme 42 kg for 7 hours. Subsequently, a first reaction gas was prepared by dropping the mixed solution in the powder reactor 110 into the main reactor 120. Since the purification process was carried out according to Example 1, the high-purity diborane (B ₂ H ₆ ) produced was 99.99% pure, but the recovery rate was low at 50.9%.

The reason for the low recovery rate in the control example is that the solvent used is Diglyme and NaBH ₄ This is because NaBH ₄ was not sufficiently dissolved in the process even though the temperature was raised to 35°C for dissolution of the mixture, and the reaction was high in Example 1 of the present invention because the powder reactor 110 produced a mixed solution. It is estimated that the main reactor 120 uses a BF ₃ co-reaction process and a continuous process to produce a BF ₃ -adduct intermediate.

[Control Example 2] (Used solvent: Triglyme (Triethylene glycol dimethyl ether; C ₈ H ₁₈ O ₄ ))

The conditions of the control example 1 are the same, NaBH ₄ 9.86 kg and the solvent were prepared using Triglyme, and 55.8 kg of Triglyme was added to the main reactor 120 and 132.7 kg of Triglyme was added to the powder reactor 110. The high-purity diborane (B ₂ H ₆ ) prepared according to the control example was prepared with a purity of 99.99% and the recovery rate was 33.7%.

Figure 3 shows the production conditions and production rates and recovery rates according to the respective examples and control examples.

As shown in FIG. 3, when compared to Comparative Examples 1 and 2, Examples 1 and 2 according to the present invention can obtain 99.99% high purity diborane (B ₂ H ₆ ) with a recovery rate of about 70% or more. Can be seen.

As described above, according to the present invention, it is possible to minimize the process, and the manufacturing efficiency and cost can be drastically reduced by the BF ₃ simultaneous reaction process, and the entire manufacturing/refining process is below atmospheric pressure (below 0 bar _g ) It has the effect of maximizing safety by completely removing the risk factors caused by internal ignition, air pollution, etc. as it consists of a vacuum process. In addition, high-purity diborane (B ₂ H ₆ (99.99% or more)) gas production is possible and has an advantage that can be applied to various industrial processes as well as semiconductor processes.

The description of the above embodiment is merely an example with reference to the drawings for a more thorough understanding of the present invention, and should not be construed as limiting the present invention. In addition, it will be apparent to those skilled in the art to which the present invention pertains that various changes and modifications are possible without departing from the basic principles of the present invention.

110: powder reactor 120: main reactor
210: frozen trap 220: adsorption module
240: distillation column 310: storage tank

Claims (21)

A first step of dissolving NaBH ₄ (Sodium Borohydride) powder in an ether-based solvent in a powder reactor at room temperature to produce a mixed solution;
The mixed solution is transferred to the main reactor using gravity and differential pressure, and BF ₃ (Boron trifluoride) gas is injected into the main reactor at a constant rate to react with the mixed solution to impurity and diborane (B ₂ H ₆ : diborane) a second step of generating a first reaction gas mixed with gas;
And a third step of purifying the first reaction gas by removing impurities through a purification process. The method according to claim 1, wherein the purification process,
By allowing the first reaction gas to pass through a freezing trap at -60 to -80°C, BF ₃ (Boron trifluoride) reacts with the ether-based solvent to form primary impurities including impurities and ether impurities. Freezing or liquefying to remove, thereby generating a second reaction gas;
The second reaction gas is introduced into an adsorption tower, and a second impurity containing high-order borane, carbon dioxide (CO ₂ ), water vapor (H ₂ O), and methane gas (CH ₄ ) is removed using an adsorbent to remove the third impurity. Generating a reaction gas;
The third reaction gas is introduced into a distillation column to perform a distillation process using a boiling point difference to remove a third impurity containing hydrogen gas (H ₂ ) and methane gas (CH ₄ ) to remove high-purity diborane of 99.99% or more ( diborane). The method according to claim 2, The distillation process,
A transfer step of transferring the third reaction gas to a distillation column;
By maintaining the inside of the distillation column at a temperature of -100 to -140°C using a refrigerant, diborane (B ₂ H ₆ :diborane) gas is liquefied and moves to the bottom of the distillation column by gravity, and the third impurity is A first distillation step of maintaining the vaporized state to collect at the top of the distillation column and removing it;
A re-transfer step of vaporizing liquefied diborane using a vaporizer and transferring the vaporized diborane (B ₂ H ₆ :diborane) gas to the distillation column;
Debo characterized by having a second distillation step to remove the fine impurity gas not removed through the first distillation step, by maintaining the inside of the distillation column at a temperature of -100 ~ -140 ℃ using a refrigerant. Lane manufacturing method. The method according to claim 1,
When the first reaction gas is generated in the main reactor in the second step, the powder reactor dissolves NaBH ₄ (Sodium Borohydride) powder in an ether-based solvent to perform a process of generating a mixed solution to perform the main reaction. Diborane production method characterized in that provided to the reactor. The method according to claim 1,
The ether-based solvent is triglyme (Triethylene glycol dimethyl ether; C ₈ H ₁₈ O ₄ ) Or tetraglyme (Tetraethylene glycol dimethyl ether; C ₁₀ H ₂₂ O ₅ ). The method according to claim 1,
The main reactor in the second step is a diborane production method characterized in that the reactor temperature is maintained at 5 ~ 10 ℃ to minimize the vaporization of impurities. The method according to claim 1,
In the second step, the BF ₃ (Boron trifluoride) gas is slowly injected into the main reactor at a rate of 3 to 4 kg/hour. The method according to claim 2,
The adsorption tower is a zeolite 4A (MS (Molecular sieve) 4A), activated carbon and zeolite 13X (MS 13X) as an adsorbent is sequentially filled from bottom to top in a volume ratio of 1:1:1. The method according to claim 2,
The adsorption tower is a diborane production method characterized in that the adsorption process performs a low temperature adsorption with a reaction temperature of -30 to -20 °C, and performs a high temperature regeneration with a reaction temperature of 200 to 350 °C during a regeneration process. The method according to claim 3,
The vaporizer in the re-transfer step is diborane production method characterized in that the reaction temperature is maintained at 5 ~ 10 ℃ to minimize the vaporization of impurities. The method according to claim 3,
After the second distillation step, a diborane production method characterized in that it comprises a storage step of storing the diborane (diborane) in which impurities are removed in a storage tank in a liquefied state. The method according to claim 1,
The first to third steps are diborane production method characterized in that it is performed in a pressure atmosphere lower than atmospheric pressure. A powder reactor that dissolves NaBH ₄ (Sodium Borohydride) powder in an ether-based solvent at room temperature to produce a mixed solution;
The mixed solution is transferred using gravity and differential pressure, and BF ₃ (Boron trifluoride) gas is injected into the transferred mixed solution at a constant rate to react with the mixed solution to impurity and diborane (B ₂ H ₆ :diborane) A main reactor for generating a first reaction gas mixed with gas;
And a purification unit that removes and purifies the first reaction gas through a purification process. The method according to claim 13, The purification unit,
While the temperature of -60 to -80°C is maintained, and the first reaction gas passes, BF ₃ (Boron trifluoride) is reacted with the ether-based solvent to freeze the primary impurities including impurities and ether impurities. A freezing trap that is removed by liquefaction to generate a second reaction gas;
By introducing the second reaction gas, a third reaction gas is removed by removing secondary impurities including high-order borane, carbon dioxide (CO ₂ ), water vapor (H ₂ O), and methane gas (CH ₄ ) using an adsorbent. Adsorption module for generating;
A distillation column that generates diborane by removing the third impurity containing hydrogen gas (H ₂ ) and methane gas (CH ₄ ) by performing the distillation process using the boiling point difference by introducing the third reaction gas A device for manufacturing diborane, characterized in that it is provided. The method according to claim 14,
And a vaporizer configured to vaporize the liquefied diborane discharged from the distillation column to perform a distillation process again in the distillation column. The method according to claim 13, The adsorption module,
Equipped with two adsorption towers alternately performing an adsorption process and a regeneration process, and a valve box for controlling opening and closing of valves connected to the two adsorption towers,
The adsorption tower is a devo characterized by having a structure in which zeolite 4A (MS (Molecular sieve) 4A), activated carbon and zeolite 13X (MS 13X) are sequentially filled from bottom to top in a volume ratio of 1:1:1 as an adsorbent. Lane manufacturing equipment. The method according to claim 16,
The adsorption tower is a diborane production apparatus characterized in that it performs low temperature adsorption with a reaction temperature of -30 to -20 °C during the adsorption process, and performs high temperature regeneration with a reaction temperature of 200 to 350 °C during the regeneration process. The method according to claim 16,
A device for manufacturing diborane, characterized in that the linear velocity of the second reaction gas passing through the adsorbent is controlled through the valve box at 0.01 to 1 Nm/sec. The method according to claim 14,
The main reactor, a flow meter (flowmeter) or mass flow controller (MFC) for injecting BF ₃ (Boron trifluoride) gas into the main reactor at a rate of 3 to 4 kg/hour is provided. Device. The method according to claim 14,
Diborane production apparatus, characterized in that the length of the distillation column to the depth ratio (L (length) / D (Depth)) is 10 to 15. The method according to claim 14,
A storage tank for liquefying and storing diborane from which impurities have been removed through the distillation column;
Diborane (diborane) stored in the storage tank diborane manufacturing apparatus characterized in that it further comprises a charging unit for filling the cylinder.

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