Method for producing phosphorus trifluoride

Abstract

A method for producing phosphorus trifluoride by reacting a metal fluoride, a phosphorus chloride compound, and a solvent according to the present invention uses a continuous production device including a screw reactor to produce phosphorus trifluoride, and thus can continuously mass-produce high-purity phosphorus trifluoride, has excellent selectivity for phosphorus trifluoride, and can reduce production costs and energy, thus being economical.

Description

Method for manufacturing phosphorus trifluoride

[0001] The present invention relates to a method for manufacturing phosphorus trifluoride.

[0002] Phosphorus trifluoride is an industrial gas that can be used, for example, as a specialty gas. Specialty gases possess a purity higher than that required for general industrial applications and are intended for specific uses. Specialty gases may include electronic and semiconductor gases, standard gases, rare gases, and mixed gases.

[0003] Specifically, phosphorus trifluoride can be used as a specialty gas for semiconductors, such as for semiconductor manufacturing and research, and for TFT-LCD manufacturing. For example, phosphorus trifluoride can be used in etching or cleaning processes during semiconductor fabrication. In this case, the purity of phosphorus trifluoride can affect the degree of etching and pattern formation of the semiconductor wafer. Therefore, to be used as a specialty gas for semiconductors, a higher purity is required than that required for general industrial gases.

[0004] A conventional method for producing phosphorus trifluoride involves reacting hydrogen fluoride with a phosphorus compound. Hydrogen fluoride, the raw material, requires special caution during handling because its strong hydrogen bonding can cause violent exothermic reactions or explosions upon contact with moisture in the air. Furthermore, not only hydrogen fluoride but also its byproducts are highly acidic substances, posing significant limitations to their application in industrial settings.

[0005] Therefore, efforts are required to find safe raw materials that can replace hydrogen fluoride in the production of phosphorus trifluoride. However, in conventional technology, it is not easy to optimize processes such as chemical reaction, purification, mixing, and extraction to ensure process safety by changing the types of reactants, while simultaneously increasing the purity of phosphorus trifluoride gas.

[0006] In addition, conventional phosphorus trifluoride was manufactured using batch or batch-type equipment. In this case, since the process of injecting raw materials into a reactor, heating the reactor to react for a certain period, and then cooling had to be repeated for every batch, there was a problem in that it was difficult to manufacture phosphorus trifluoride in large quantities due to not only high costs but also very low productivity.

[0007] One aspect of the present invention for solving the aforementioned problem is to provide an economical method for producing phosphorus trifluoride, which can continuously mass-produce high-purity phosphorus trifluoride using a screw reactor, has excellent selectivity for phosphorus trifluoride, and can reduce manufacturing costs and energy.

[0008] The technical problems intended to be solved in this document are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which this invention belongs from the description below.

[0009] To achieve the above objective, a method for producing phosphorus trifluoride according to one embodiment of the present invention, wherein phosphorus trifluoride is produced by reacting a metal fluoride salt, a phosphorus chloride compound, and a solvent, said phosphorus trifluoride can be produced using a continuous production apparatus including a screw reactor.

[0010] The manufacturing method according to one embodiment of the present invention may include the step of introducing a metal fluoride salt into a screw reactor of a continuous manufacturing apparatus; and the step of introducing a phosphorus chloride compound and a solvent into the screw reactor to obtain a reaction product containing phosphorus trifluoride.

[0011] The manufacturing method according to one embodiment of the present invention may further include a step of vacuum purging the inside of the screw reactor with an inert gas after the step of introducing a metal fluoride salt.

[0012] The continuous manufacturing apparatus according to one embodiment of the present invention may include: a screw reactor comprising an internal space isolated from the outside air, a raw material inlet for introducing raw materials, and an outlet for discharging phosphorus trifluoride to the outside; a raw material supply unit comprising a supply space for storing raw materials and connected to the raw material inlet of the screw reactor to supply raw materials to the internal space of the screw reactor; a transfer screw installed in the internal space of the screw reactor to transfer raw materials introduced into the internal space of the screw reactor through the raw material inlet to the outlet; and a phosphorus trifluoride storage unit connected to the outlet of the screw reactor and having a storage space isolated from the outside air.

[0013] According to one embodiment of the present invention, the conveying screw includes a spiral blade, and the spiral blade may be installed adjacent to at least one surface inside the screw reactor.

[0014] The raw material according to one embodiment of the present invention may include a metal fluoride salt, a phosphorus chloride compound, and a solvent.

[0015] According to one embodiment of the present invention, the raw material supply unit may include a metal fluoride salt supply unit, a phosphorus chloride compound supply unit, and a solvent supply unit.

[0016] The above raw material supply unit is connected to the raw material inlet of the screw reactor and the raw material transfer unit, and the raw material transfer unit may further include a raw material mixing unit for mixing the raw materials.

[0017] The screw reactor according to one embodiment of the present invention may further include a heating means for raising the temperature of the internal space.

[0018] The screw reactor according to one embodiment of the present invention may further include a cooling means.

[0019] According to one embodiment of the present invention, a phosphorus trifluoride purification unit connected to the phosphorus trifluoride storage unit may be further included.

[0020] According to one embodiment of the present invention, the screw reactor may further include an unreacted material recovery unit connected to the screw reactor and for storing unreacted material.

[0021] The metal fluoride salt according to one embodiment of the present invention may include a compound represented by the following chemical formula 1.

[0022] [Chemical Formula 1]

[0023] M a F n

[0024] (In the above chemical formula 1, M a is an alkali metal or alkaline earth metal, and n is 1 to 3.

[0025] The metal fluoride salt according to one embodiment of the present invention may include a compound selected from one or more of sodium fluoride, potassium fluoride, calcium fluoride, and magnesium fluoride.

[0026] According to one embodiment of the present invention, the phosphorus chloride may include phosphorus trichloride (PCl3).

[0027] The solvent according to one embodiment of the present invention may include one or more selected from acetonitrile, toluene, and dimethylformamide.

[0028] According to one embodiment of the present invention, the phosphorus chloride compound and the metal fluoride salt may be included in a weight ratio of 1:1.5 to 1:20.

[0029] According to one embodiment of the present invention, the phosphorus chloride compound and solvent may be included in a weight ratio of 2.5:1 to 10:1.

[0030] The reaction step according to one embodiment of the present invention may further include a catalyst represented by the following chemical formula 2.

[0031] [Chemical Formula 2]

[0032] (M b ) x A y

[0033] (In the above chemical formula 2, M b is at least one selected from Sb, Fe, Sn, Ti, and Al, A is a halogen atom or an oxygen atom, and x and y are each independently 1 to 3. The above x and y are real numbers.)

[0034] The catalyst according to one embodiment of the present invention may include one or more selected from diantimony trioxide (Sb2O3), antimony fluoride (SbF3), iron trioxide (Fe2O3), iron fluoride (FeF3), tin fluoride (SnF4), titanium fluoride (TiF4), and aluminum fluoride (AlF3).

[0035] According to one embodiment of the present invention, the solvent and the catalyst may be included in a weight ratio of 1:0.1 to 1:0.0001.

[0036] According to one embodiment of the present invention, the phosphorus chloride compound can be prepared as a phosphorus chloride compound solution by mixing it with a solvent before reacting it with a metal fluoride salt.

[0037] According to the present invention, high-purity phosphorus trifluoride can be continuously mass-produced using a screw reactor, and an economical method for producing phosphorus trifluoride can be provided by having excellent selectivity for phosphorus trifluoride and reducing manufacturing costs and energy.

[0038] The effects obtainable from the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present invention belongs from the description below.

[0039] FIG. 1 is a schematic diagram illustrating the configuration of a continuous phosphorus trifluoride manufacturing apparatus according to one embodiment of the present invention.

[0040] FIG. 2 is a schematic diagram illustrating another form of a helical conveying screw of a phosphorus trifluoride continuous manufacturing apparatus according to one embodiment of the present invention.

[0041] Preferred embodiments of the present invention are described below. However, embodiments of the present invention may be modified in various other forms, and the technical concept of the present invention is not limited to the embodiments described below. Furthermore, the embodiments of the present invention are provided to more completely explain the present invention to those with average knowledge in the relevant technical field.

[0042] The terms used in this application are used merely to describe specific examples. For this reason, singular expressions include plural expressions unless the context clearly requires them to be singular. Additionally, it should be noted that terms such as “comprising” or “comprising” used in this application are used to clearly indicate the presence of features, steps, functions, components, or combinations thereof described in the specification, and are not used to preliminarily exclude the existence of other features, steps, functions, components, or combinations thereof.

[0043] Meanwhile, unless otherwise defined, all terms used in this specification shall be understood to have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Accordingly, unless explicitly defined in this specification, specific terms should not be interpreted in an overly ideal or formal sense. For instance, singular expressions in this specification include plural expressions unless the context clearly indicates an exception.

[0044] Additionally, terms such as "about," "substantially," etc., in this specification are used to mean at or near the stated value when inherent manufacturing and material tolerances are presented in the said sense, and are used to prevent unscrupulous infringers from unfairly exploiting the disclosed content in which precise or absolute values ​​are mentioned to aid in understanding the invention.

[0045] A method for manufacturing phosphorus trifluoride according to one embodiment of the present invention will be described in detail below.

[0046] A method for producing phosphorus trifluoride according to one embodiment of the present invention, wherein phosphorus trifluoride is produced by reacting a metal fluoride salt, a phosphorus chloride compound, and a solvent, said phosphorus trifluoride can be produced using a continuous production apparatus including a screw reactor.

[0047] According to the phosphorus trifluoride manufacturing method of the present invention, high-purity phosphorus trifluoride can be produced with excellent yield and selectivity while replacing hydrogen fluoride. Furthermore, by using a continuous manufacturing apparatus including a screw reactor, the reaction rate of raw materials can be further enhanced by the screw reactor, and phosphorus trifluoride can be manufactured continuously, thereby enabling mass production of phosphorus trifluoride while reducing manufacturing costs and energy.

[0048] Specifically, the above manufacturing method may include the step of introducing a metal fluoride salt into a screw reactor of a continuous manufacturing apparatus and the step of introducing a phosphorus chloride compound and a solvent into the screw reactor to obtain a reaction product containing phosphorus trifluoride.

[0049] In addition, after the above-mentioned step of introducing a metal fluoride salt, a step of vacuum purging the inside of the screw reactor with an inert gas may be further included.

[0050] Hereinafter, a continuous manufacturing apparatus including a screw reactor according to one embodiment of the present invention will be described in detail with reference to the attached drawings.

[0051] FIG. 1 is a schematic diagram illustrating the configuration of a continuous manufacturing apparatus including a screw reactor according to a preferred embodiment of the present invention. As shown in FIG. 1, the continuous manufacturing apparatus including a screw reactor according to the present invention (hereinafter referred to as the "apparatus") comprises a screw reactor (1) for manufacturing phosphorus trifluoride, a raw material supply unit (30) connected to one side of the screw reactor (1), a phosphorus trifluoride storage unit (40) connected to the screw reactor (1), a phosphorus trifluoride purification unit (50) connected to the phosphorus trifluoride storage unit (40), and an unreacted material recovery unit (60) connected to the screw reactor (1).

[0052] The screw reactor (1) is a cylindrical type containing a cylindrical internal space isolated from the outside air, and a raw material inlet (2) connected to a raw material supply unit (30) is formed adjacent to the front end of the screw reactor (1). A screw reactor-side trifluoride discharge port (3) is formed at the rear end of the screw reactor (1), and an unreacted material discharge port (4) that opens downward is formed on the bottom surface of the rear end of the screw reactor (1).

[0053] The screw reactor (1) is formed to be long in the longitudinal direction, but since the drawing is simplified for the sake of simplification of the description, the shape of the screw reactor (1) is not limited by the dimensional ratio of the drawing.

[0054] A heating means (15) is installed on the outside of the screw reactor (1) from the front end to the rear end of the screw reactor (1). The heating means (15) includes a temperature sensor (not shown) and maintains the temperature of the internal space of the screw reactor (1) at 25 to 100°C.

[0055] A spiral conveying screw (20) is installed in the longitudinal direction inside the screw reactor (1). The spiral conveying screw (20) includes a shaft (21) and spiral blades (22) formed around the shaft (21), and the shaft (21) of the spiral conveying screw (20) is connected to a motor (M) installed outside the screw reactor (1). The spiral conveying screw (20) is installed so that the lower part of the spiral blades (22) maintains a certain distance from the bottom surface inside the screw reactor (1). If the distance between the spiral blades (22) and the bottom surface of the screw reactor (1) is large, raw materials will accumulate in that distance, but even so, it is not impossible to convey raw materials, reaction products, reactants, unreacted materials, etc., but only the raw materials, reaction products, reactants, unreacted materials will accumulate on the bottom in a certain thickness. The shaft (21) of the spiral transfer screw (20) may have a rigid structure such as a metal bar, or it may have a flexible structure such as a wire rope. However, since the spiral transfer screw (20) is used in a high-temperature screw reactor (1), a material with excellent heat resistance, such as a metal or ceramic material with good heat resistance, or a corrosion-resistant metal material is used considering the toxicity and corrosiveness characteristics of the raw materials and products.

[0056] The helical feed screw (20) does not necessarily require a shaft (21), and as shown in FIG. 2, it is also possible to use a structure in which the helical feed screw (23) consists only of helical blades (24) without a shaft (21), similar to a coil spring shape. Even when using a shaftless helical feed screw (23), its end is connected to a motor.

[0057] The raw material supply unit (30) is for supplying a certain amount of raw material into the internal space of the screw reactor (1) and includes a metal fluoride salt supply unit (31), a phosphorus chloride compound supply unit (32), and a solvent supply unit (33). Each supply unit (31, 32, 33) has a storage space formed inside to store the metal fluoride salt, phosphorus chloride, and solvent, respectively, and includes a raw material transfer path (34, 35) connected to the raw material inlet (2) of the screw reactor (1).

[0058] The phosphorus chloride compound and solvent discharged from the phosphorus chloride compound supply unit (32) and the solvent supply unit (33) may be mixed before being introduced into the internal space of the screw reactor (1) to be prepared as a phosphorus chloride compound solution and then introduced into the internal space of the screw reactor (1). Accordingly, the raw material transfer path (35) may include a raw material mixing unit (not shown) for mixing the phosphorus chloride compound and the solvent.

[0059] Additionally, the metal fluoride supplied from the metal fluoride supply unit (31) may be mixed with a catalyst before being introduced into the internal space of the screw reactor (1). To this end, the raw material supply unit (30) may additionally include a catalyst supply unit (not shown), and a raw material mixing unit (not shown) for mixing the metal fluoride and the catalyst may be included in the raw material transport path (34).

[0060] The metal fluoride supplied from the metal fluoride salt supply unit (31) may include one or more selected from sodium fluoride, potassium fluoride, calcium fluoride, and magnesium fluoride. The phosphorus chloride compound supplied from the phosphorus chloride compound supply unit (32) may be phosphorus trichloride (PCl3). The solvent supplied from the solvent supply unit (33) may include one or more selected from acetonitrile, toluene, and dimethylformamide. The catalyst may include one or more selected from antimony trioxide (Sb2O3), antimony fluoride (SbF3), ferric trioxide (Fe2O3), iron fluoride (FeF3), tin fluoride (SnF4), titanium fluoride (TiF4), and aluminum fluoride (AlF3).

[0061] A phosphorus trifluoride storage unit (40) is provided with a first phosphorus trifluoride transfer path (41) connected to a phosphorus trifluoride discharge port (3) formed at the rear end of a screw reactor (1), and a phosphorus trifluoride storage space is formed inside the storage unit (40). Additionally, a second phosphorus trifluoride transfer path (43) connected to a phosphorus trifluoride discharge port (42) on the storage unit side is provided at the rear end of the storage unit (40), and the second phosphorus trifluoride transfer path (43) is connected to a phosphorus trifluoride purification unit (50).

[0062] The unreacted material recovery unit (60) is connected to the screw reactor (1), and a storage space for unreacted material discharged through the unreacted material discharge port (4) of the screw reactor (1) is formed inside the unreacted material recovery unit (60).

[0063] In a continuous manufacturing apparatus including a screw reactor according to one embodiment of the present invention, the helical conveying screw plays the role of stirring raw materials (metal fluoride salt, phosphorus chloride compound, and solvent) introduced into the internal space of the screw reactor (1) while simultaneously continuously conveying reaction products, reactants, unreacted materials, etc. Since the helical blade (22) of the helical conveying screw (20) plays the role of pushing the raw materials forward and simultaneously pushing them in the circumferential direction, the raw materials are stirred evenly, thereby promoting the reaction of the raw materials and enabling the rapid production of phosphorus trifluoride, which is a reaction product. In addition, the helical blade (22) of the conveying screw is formed adjacent to the bottom surface of the internal space of the screw reactor (1) to push and advance the raw materials accumulated in the internal space of the screw reactor (1), but it is not necessary for it to be in close contact with the bottom surface of the internal space of the screw reactor (1). In addition, although the spiral wings (22) are formed to be continuously connected in this embodiment, it is also possible to have a suitable structure for performing a conveying function, such as a plurality of spiral wings (22) arranged at a predetermined interval in a spiral shape.

[0064] In a continuous manufacturing apparatus including a screw reactor according to an embodiment of the present invention, the raw material supply unit (30) is configured to supply a certain amount of raw material during the phosphorus trifluoride manufacturing process of the apparatus, but the present invention is not limited thereto, and the amount of raw material supplied during the phosphorus trifluoride manufacturing process of the apparatus may vary, and in this case, the amount of phosphorus trifluoride produced may vary.

[0065] In a continuous manufacturing apparatus including a screw reactor according to an embodiment of the present invention, the spiral conveying screw may be formed over the entire length of the internal space of the screw reactor (1), or it may be formed over a variety of ranges as long as the condition of including the section from the raw material inlet (2) of the screw reactor (1) to the trifluoride outlet (3) is satisfied.

[0066] In a continuous manufacturing apparatus including a screw reactor according to an embodiment of the present invention, a phosphorus trifluoride purification unit (50) connected to a phosphorus trifluoride storage unit (40) is included, but the present invention is not limited thereto, and if the manufactured phosphorus trifluoride is purified through a separate process, it is also possible to omit the phosphorus trifluoride purification unit (50) from the apparatus of the present invention.

[0067] In a continuous manufacturing apparatus including a screw reactor according to an embodiment of the present invention, the shape of the screw reactor (1) is cylindrical, but the present invention is not limited thereto and can be formed in various structures.

[0068] Next, a method for producing phosphorus trifluoride using a continuous manufacturing apparatus including a screw reactor according to one embodiment of the present invention will be described.

[0069] A method for producing phosphorus trifluoride according to one embodiment of the present invention can be produced by using a continuous production apparatus including a screw reactor as described above, in a method for producing phosphorus trifluoride by reacting a metal fluoride salt, a phosphorus chloride compound, and a solvent.

[0070] Specifically, the above manufacturing method may include the step of introducing a metal fluoride salt into a screw reactor of a continuous manufacturing apparatus, and the step of introducing a phosphorus chloride compound and a solvent into the screw reactor to obtain a reaction product containing phosphorus trifluoride. Additionally, after the step of introducing the metal fluoride salt, the method may further include the step of vacuum purging the inside of the screw reactor with an inert gas.

[0071] The metal fluoride salt used in the above-mentioned production of phosphorus trifluoride may be a dried metal fluoride salt or a regenerated metal fluoride salt. Specifically, the metal fluoride salt may refer to a solid compound formed by the combination of a metal and fluorine. In one example, the metal fluoride salt may be in an anhydrous or hydrated state. In this case, it can replace the hydrogen fluoride used as a reactant, thereby improving the safety of the entire process.

[0072] The above metal fluoride salt may be a compound represented by the following chemical formula 1.

[0073] [Chemical Formula 1]

[0074] M a F n

[0075] In the above chemical formula 1, M a is an alkali metal or alkaline earth metal, and n is 1 to 3.

[0076] When the compound of Chemical Formula 1 above is used as a metal fluoride salt, the overall process safety and reactivity can be improved to an excellent degree.

[0077] Specifically, the metal fluoride salt may be one or more selected from sodium fluoride (NaF), potassium fluoride (KF), calcium fluoride (CaF2), and magnesium fluoride (MgF2), and preferably may be sodium fluoride (NaF). When the compound is used as the metal fluoride salt, the selectivity of phosphorus trifluoride can be improved while further increasing overall process safety.

[0078] The phosphorus chloride compound used in the above preparation of phosphorus trifluoride may be phosphorus trichloride (PCl3).

[0079] The solvent used in the above preparation of phosphorus trifluoride may be one or more selected from acetonitrile, toluene, and dimethylformamide (DMF). When the above compounds are used as solvents, the selectivity of phosphorus trifluoride can be improved while further increasing the overall process safety, thereby further increasing the purity and yield of phosphorus trifluoride.

[0080] The above phosphorus chloride compound may also be prepared as a phosphorus chloride compound solution by first mixing it with a solvent prior to mixing it with a metal fluoride salt.

[0081] The phosphorus chloride compound and the solvent may be mixed in a weight ratio of 2.5:1 to 10:1, and preferably in a weight ratio of 3:1 to 8:1. When the phosphorus chloride compound and the solvent are mixed within the above range, the solubility characteristics of the phosphorus chloride compound are improved, which can further improve the final yield of phosphorus trifluoride.

[0082] In addition, the phosphorus chloride compound and the metal fluoride salt may be mixed in a weight ratio of 1:1.5 to 1:20, and preferably in a weight ratio of 1:2.5 to 1:10. When the phosphorus chloride compound and the metal fluoride salt are mixed within the above range, the formation of by-products during the production of phosphorus trifluoride can be suppressed, thereby further improving the conversion rate and reaction yield.

[0083] In addition to the metal fluoride salt, phosphorus chloride compound, and solvent described above, a catalyst may be further included in the production of phosphorus trifluoride.

[0084] The above catalyst can shorten the reaction time by promoting the reaction of metal fluoride salts and phosphorus chloride compounds, and can improve the time to reach the equilibrium conversion rate of phosphorus trifluoride, the reaction yield, and the selectivity of phosphorus trifluoride.

[0085] The above catalyst may be a compound represented by the following chemical formula 2.

[0086] [Chemical Formula 2]

[0087] (M b ) x A y

[0088] (In the above chemical formula 2, M b is at least one selected from Sb, Fe, Sn, Ti, and Al, A is a halogen atom or an oxygen atom, and x and y are each independently 1 to 3. The above x and y are real numbers.)

[0089] When the compound of Chemical Formula 2 above is used as a catalyst, the overall process safety and reactivity can be improved to an excellent degree, and the overall reaction rate can be improved or the time required to reach the equilibrium conversion rate of phosphorus trifluoride can be shortened.

[0090] Specifically, the catalyst may be one or more selected from diantimony trioxide (Sb2O3), antimony fluoride (SbF3), iron trioxide (Fe2O3), iron fluoride (FeF3), tin fluoride (SnF4), titanium fluoride (TiF4), and aluminum fluoride (AlF3), and preferably diantimony trioxide (Sb2O3). When the above compound is used as a catalyst, the effect of improving the overall reaction rate or shortening the time to reach the equilibrium conversion rate of phosphorus trifluoride may be further enhanced.

[0091] The solvent and catalyst included in the above mixture may be mixed in a weight ratio of 1:0.1 to 1:0.0001. If the weight ratio of the catalyst to the solvent exceeds 1:0.1, economic efficiency may be reduced and catalytic activity may be lowered, and if it is less than 1:0.0001, the role of the catalyst may be negligible.

[0092] A method for producing phosphorus trifluoride using a continuous apparatus including a screw reactor according to one embodiment of the present invention can be carried out as follows.

[0093] In one example, the method for producing phosphorus trifluoride according to the present invention may include the step of introducing a metal fluoride salt into a screw reactor of a continuous manufacturing apparatus and the step of introducing a phosphorus chloride compound and a solvent into the screw reactor to obtain a reaction product containing phosphorus trifluoride.

[0094] After raising the temperature of the internal space of the screw reactor (1) to 20 to 100°C using a heating means (15), the metal fluoride salt, phosphorus chloride compound, and solvent discharged from the raw material supply unit (30), specifically the metal fluoride salt supply unit (31), the phosphorus chloride compound supply unit (32), and the solvent supply unit (33), pass through the raw material transfer path (34, 35) and are introduced into the internal space of the screw reactor (1) through the raw material inlet (2) of the screw reactor (1).

[0095] Prior to mixing with the metal fluoride salt, the phosphorus chloride compound and the solvent can be mixed in advance to form a phosphorus chloride compound solution, which can then be mixed with the metal fluoride salt.

[0096] The metal fluoride salt introduced into the internal space of the screw reactor (1) in advance may further perform the step of vacuum purging the internal space of the screw reactor (1) with an inert gas prior to the introduction of the phosphorus chloride compound solution, and after vacuum purging by the inert gas, the phosphorus chloride compound solution is introduced into the screw reactor (1).

[0097] At this time, vacuum purging by the inert gas is performed to remove moisture or oxygen from the internal space of the screw reactor (1) before the metal fluoride salt comes into contact with the phosphorus chloride compound solution. This reduces the generation of by-product HCl by reacting the moisture or oxygen from the internal space of the screw reactor (1) with the reaction product phosphorus trichloride, thereby further increasing the purity and yield of phosphorus trifluoride.

[0098] The vacuum purging by the above inert gas may be performed after the metal fluoride salt is introduced into the screw reactor (1), or it may be performed after it is discharged from the metal fluoride salt supply unit (31) and before it is introduced into the screw reactor (1).

[0099] The above inert gas is not particularly limited, but may be, for example, nitrogen, helium, etc.

[0100] The metal fluoride salt, phosphorus chloride compound, and solvent introduced into the screw reactor (1) react to produce phosphorus trifluoride. At this time, the reaction rate of the metal fluoride salt, phosphorus chloride compound, and solvent is accelerated by the rotation of the spiral conveying screw (20), and at the same time, the reaction products generated by the reaction, raw materials, reactants, unreacted materials, etc. are moved to the rear of the screw reactor (1) by the spiral conveying screw (20).

[0101] The reaction using the above screw reactor (1) can be carried out at room temperature (25°C) for 30 minutes to 5 hours, and the screw rotation speed can be adjusted according to the length and width of the screw, for example, the screw rotation speed can be adjusted to 1 to 50 rpm, preferably 1 to 10 rpm.

[0102] Since the raw materials, reaction products, reactants, unreacted materials, etc. introduced into the internal space of the screw reactor (1) are stirred by the rotation of the spiral conveying screw (20), the materials are prevented from sticking to each other and reducing homogeneity. Of course, the reactivity and yield of the phosphorus trifluoride can also be controlled by adjusting the reaction temperature, reaction time, reaction speed, etc., during the production of the phosphorus trifluoride.

[0103] The manufactured phosphorus trifluoride is discharged through the screw reactor-side phosphorus trifluoride discharge port (3) formed at the rear end of the screw reactor (1) and moves to the phosphorus trifluoride storage unit (40) via the first phosphorus trifluoride transfer path (41).

[0104] In this way, raw materials are continuously introduced into the internal space of the screw reactor (1) through the raw material supply unit (30), and the continuously introduced raw materials are continuously stirred by the rotation of the spiral conveying screw (20) in the internal space of the screw reactor (1) to produce reaction products and are simultaneously conveyed to the phosphorus trifluoride discharge port (42), so that continuous production of phosphorus trifluoride is possible, and phosphorus trifluoride can be mass-produced.

[0105] In addition, the method for manufacturing phosphorus trifluoride according to the present invention may further perform a step of purifying the manufactured phosphorus trifluoride, and the phosphorus trifluoride manufactured in the screw reactor (1) may exit through the phosphorus trifluoride discharge port (42) on the storage side, pass through the second phosphorus trifluoride transfer path (43), and be introduced into the phosphorus trifluoride purification unit (50) to perform a purification step.

[0106] When manufacturing phosphorus trifluoride, the reaction product containing the phosphorus trifluoride may contain, in addition to the desired product, phosphorus trifluoride, low proportions of unreacted raw materials, unreacted solvents, reaction by-products, moisture, etc. By additionally performing a step of purifying phosphorus trifluoride from the reaction product containing the phosphorus trifluoride, the purity and / or yield of phosphorus trifluoride can be further increased.

[0107] Meanwhile, unreacted raw materials, unreacted solvents, reaction by-products, moisture, etc., contained in the reaction product containing phosphorus trifluoride are discharged through the unreacted material discharge port (4) of the screw reactor (1) and transferred to the unreacted material recovery unit (60).

[0108] The present invention will be explained in more detail below through the following examples. However, the following examples are merely illustrative of the present invention, and the scope of the present invention is not limited thereto.

[0109] Examples 1-4

[0110] Phosphorus trifluoride was produced using a continuous manufacturing apparatus including a screw reactor as shown in Fig. 1. First, the internal temperature of the screw reactor was raised to 100°C by a heating means, and 2.75 parts by weight of NaF were introduced into the screw reactor. Then, moisture and oxygen inside the screw reactor were removed by purging with an inert gas (N2) to form a vacuum atmosphere. Subsequently, a mixed solution comprising 1 part by weight of PCl3 and 0.2 parts by weight of acetonitrile was introduced into the screw reactor and reacted. At this time, the temperature of the screw reactor was controlled to 25°C, the reaction time to 2 hours, and the screw rotation speed was 3 rpm.

[0111] Examples 2 to 4 were carried out in the same manner as Example 1, using raw materials in the weight ratios shown in Table 1 below.

[0112] Classification NaF (parts by weight) PCl3 (parts by weight) Acetonitrile (parts by weight) Catalyst (parts by weight) Catalyst Type Example 1 2.75 10.2 0.00 3 - Example 2 2.75 10.2 0.00 3 Sb2O3 Example 3 2.75 10.2 0.00 3 SbF3 Example 4 2.75 10.2 0.00 3 FeF3

[0113] Comparative Examples 1~2

[0114] The above example was carried out in the same manner as Example 1, except that raw materials were used in the same weight ratio as in Examples 1 and 2, but the reaction was carried out in a batch-type closed reactor.

[0115] Experimental Example 1

[0116] The reaction conversion rate, yield, selectivity, and purity for phosphorus trifluoride among the reaction products prepared in Examples 1 to 4 and Comparative Examples 1 to 2 were measured, and the results are shown in Table 1 below.

[0117] The reaction conversion rate was calculated by checking the amount of PF3 produced using a pressure gauge installed in the phosphorus trifluoride (PF3) storage unit, and the unreacted acetonitrile and PCl3 were removed by flowing a dry trap at -20℃ at a rate of 0.2 L / min and collecting the gas in a collection cylinder.

[0118] Yield was calculated as reaction conversion rate × selectivity.

[0119] Selectivity and purity were analyzed using mass spectrum.

[0120] The reaction times of Comparative Examples 1 and 2 were measured for the time after the reaction was terminated and the pressure no longer increased.

[0121] Classification Reaction Conversion Rate (%) Yield (%) Purity (%) Reaction Time Example 1 26.1 23.3 89.3 120 min Example 2 43.3 39.7 91.5 120 min Example 3 42.8 39.5 92.4 120 min Example 4 36.9 33.7 91.2 120 min Comparative Example 1 42.02 3.3 90.9 240 min Comparative Example 2 46.03 9.7 91.6 120 min

[0122] As shown in Table 2 above, in the case of Examples 1 to 4, which produced phosphorus trifluoride using a screw reactor according to the present invention, the reaction conversion rate, yield, purity, and reaction time were found to be equivalent or higher compared to Comparative Examples 1 and 2, which used a conventional batch-type closed reactor. From these results, it was found that high-purity phosphorus trifluoride can be continuously produced at a high speed using a continuous manufacturing apparatus including a screw reactor according to the present invention.

[0123] Although embodiments of the invention disclosed above have been illustrated and described, the disclosed invention is not limited to the specific embodiments described above, and various modifications may be made by those skilled in the art to which the disclosed invention belongs without departing from the essence claimed in the claims.

Claims

1. A method for producing phosphorus trifluoride by reacting a metal fluoride salt, a phosphorus chloride compound, and a solvent, A method for producing phosphorus trifluoride, wherein the phosphorus trifluoride is produced using a continuous manufacturing apparatus including a screw reactor.

2. In Paragraph 1, The above manufacturing method is, A step of introducing a metal fluoride salt into a screw reactor of a continuous manufacturing device; and A method for producing phosphorus trifluoride comprising the step of introducing a phosphorus chloride compound and a solvent into the screw reactor to obtain a reaction product containing phosphorus trifluoride.

3. In Paragraph 1, The above manufacturing method is a method for producing phosphorus trifluoride, which further includes the step of vacuum purging the inside of a screw reactor with an inert gas after the step of introducing a metal fluoride salt.

4. In Paragraph 1, The above continuous manufacturing device is, A screw reactor comprising an internal space isolated from the outside air, a raw material inlet for introducing raw materials, and an outlet for discharging phosphorus trifluoride to the outside; A raw material supply unit including a supply space for storing raw materials, connected to a raw material inlet of the screw reactor to supply raw materials into the internal space of the screw reactor; A transfer screw installed in the internal space of the screw reactor to transfer raw material introduced into the internal space of the screw reactor through the raw material inlet to the outlet; and A method for manufacturing phosphorus trifluoride comprising: a phosphorus trifluoride storage unit having a storage space connected to the outlet of the screw reactor and isolated from the outside air.

5. In Paragraph 4, A method for manufacturing phosphorus trifluoride, wherein the above-mentioned conveying screw includes a spiral blade, and the spiral blade is installed adjacent to at least one surface inside the screw reactor.

6. In Paragraph 4, The above raw material is a method for manufacturing phosphorus trifluoride comprising a metal fluoride salt, a phosphorus chloride compound, and a solvent.

7. In Paragraph 4, The above-mentioned raw material supply unit comprises a metal fluoride salt supply unit, a phosphorus chloride compound supply unit, and a solvent supply unit for the production of phosphorus trifluoride.

8. In Paragraph 4, A method for manufacturing phosphorus trifluoride, wherein the raw material supply unit is connected to the raw material inlet and the raw material transfer unit of the screw reactor, and the raw material transfer unit further includes a raw material mixing unit for mixing the raw materials.

9. In Paragraph 4, A method for manufacturing phosphorus trifluoride, wherein the screw reactor further comprises a heating means for raising the temperature of the internal space.

10. In Paragraph 4, The above screw reactor is a method for manufacturing phosphorus trifluoride, further comprising a cooling means.

11. In Paragraph 4, A method for manufacturing phosphorus trifluoride, further comprising a phosphorus trifluoride purification unit connected to the phosphorus trifluoride storage unit.

12. In Paragraph 4, A method for manufacturing phosphorus trifluoride, further comprising an unreacted material recovery unit connected to the screw reactor and for storing unreacted material.

13. In Paragraph 1, A method for preparing phosphorus trifluoride comprising a compound represented by the following chemical formula 1, wherein the metal fluoride salt above. [Chemical Formula 1] M a F n (In the above chemical formula 1, M a is an alkali metal or alkaline earth metal, and n is 1 to 3.

14. In Paragraph 1, A method for preparing phosphorus trifluoride comprising a compound in which the metal fluoride salt is one or more selected from sodium fluoride, potassium fluoride, calcium fluoride, and magnesium fluoride.

15. In Paragraph 1, The above phosphorus chloride is a method for producing phosphorus trifluoride containing phosphorus trichloride (PCl3).

16. In Paragraph 1, A method for preparing phosphorus trifluoride, wherein the solvent comprises one or more selected from acetonitrile, toluene, and dimethylformamide.

17. In Paragraph 1, A method for producing phosphorus trifluoride comprising the phosphorus chloride compound and the metal fluoride salt in a weight ratio of 1:1.5 to 1:

20.

18. In Paragraph 1, A method for producing phosphorus trifluoride comprising the above phosphorus chloride compound and solvent in a weight ratio of 2.5:1 to 10:

1.

19. In Paragraph 1, A method for producing phosphorus trifluoride, wherein the above reaction step further comprises a catalyst represented by the following chemical formula 2. [Chemical Formula 2] (M b ) x A y (In the above chemical formula 2, M b is at least one selected from Sb, Fe, Sn, Ti, and Al, A is a halogen atom or an oxygen atom, and x and y are each independently 1 to 3. The above x and y are real numbers.) 20. In Paragraph 19, A method for producing phosphorus trifluoride, wherein the catalyst comprises one or more selected from diantimony trioxide (Sb2O3), antimony fluoride (SbF3), iron trioxide (Fe2O3), iron fluoride (FeF3), tin fluoride (SnF4), titanium fluoride (TiF4), and aluminum fluoride (AlF3).

21. In Paragraph 19, A method for producing phosphorus trifluoride, comprising the solvent and the catalyst in a weight ratio of 1:0.1 to 1:0.0001.

22. In Paragraph 1, A method for preparing phosphorus trifluoride, wherein the above phosphorus chloride compound is mixed with a solvent before reacting with a metal fluoride salt to form a phosphorus chloride compound solution.

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