WO2008001844A1

WO2008001844A1 - Process for producing high-purity hexafluoropropylene and cleaning gas

Info

Publication number: WO2008001844A1
Application number: PCT/JP2007/062995
Authority: WO
Inventors: Hiromoto Ohno; Toshio Ohi
Original assignee: Showa Denko K.K.
Priority date: 2006-06-30
Filing date: 2007-06-28
Publication date: 2008-01-03
Also published as: JP5132555B2; JPWO2008001844A1; CN101479220A

Abstract

A process for industrially advantageously producing high-purity hexafluoropropylene; and a use of this high-purity hexafluoropropylene, specifically, a cleaning gas for removing deposits in a semiconductor manufacturing apparatus or liquid-crystal manufacturing apparatus. In the process for high-purity hexafluoropropylene production, crude hexafluoropropylene produced by the pyrolysis of chlorodifluoromethane is purified to thereby produce high-purity hexafluoropropylene. It comprises: a step (1) in which the crude hexafluoropropylene is brought into contact with an adsorbent comprising a zeolite having an average micropore diameter of 3.4-11 Å and/or a carbonaceous adsorbent having an average micropore diameter of 3.5-11 Å to reduce the content of chlorine compounds and/or hydrocarbons in the crude hexafluoropropylene; and a step (2) in which the hexafluoropropylene obtained in the step (1) is distilled to reduce the content of low-boiling ingredients therein.

Description

Manufacturing method of high purity hexafluoropropylene and cleaning gas

[0001] The present invention relates to a method for producing high-purity hexafluoropropylene. In particular, the present invention relates to a method for producing hexafluoropropylene and a use of high-purity hexafluoropropylene which are preferably used for removing deposits in a semiconductor production apparatus or a liquid crystal production apparatus.

Background art

[0002] Hexafluoropropylene (hereinafter referred to as “CF CF = CF” or “FC-1216”)

3 2

For example, is used as a raw material for the production of cleaning gas fluorinated propane (C F) in the semiconductor device manufacturing process. As its manufacturing method, for example,

3 8

(1) Through the thermal decomposition of chlorodifluoromethane (CHC1F) shown in the following formula, tetrafluoro

2

A method of obtaining as a by-product in the process of producing tylene (CF = CF),

twenty two

2CHC1F + H O → CF = CF + CF CF = CF

2 2 2 2 3 2

(2) A method obtained by thermally decomposing polytetrafluoroethylene or passing tetrafluoroethylene over platinum under reduced pressure at high temperature, etc.

(3) A method for denerogenizing propane, propylene or partially halogenated C3 acyclic hydrocarbons by fluorination and dehydrogenation (Japanese Patent Laid-Open No. 4-145033), etc. are known. In many cases, hexafluoropropylene has saturated and unsaturated compounds such as black mouth fluorocarbons (CFCs), hyde mouth black mouth fluorocarbons (HCFCs), and hydrocarbons (HC). Contains various impurities! These impurities are difficult to separate from hexafluoropropylene by distillation.

[0003] Therefore, in order to obtain high purity and hexafluoropropylene, it is necessary to remove these impurities as much as possible. In particular, with regard to chlorine-containing fluorocarbons and hide-mouthed fluorocarbons, which are chlorine-containing compounds, in addition to the purpose of improving the purity of hexafluoropropylene, the viewpoint of preventing the destruction of the ozone layer and semiconductor manufacturing Prevention of contamination in equipment or liquid crystal manufacturing equipment (contamination by chlorine-containing compounds in the etching chamber) From this viewpoint, it is necessary to remove compounds that are difficult to separate by ordinary distillation.

[0004] However, among the above impurities, there are compounds that are very difficult to separate from hexafluoropropylene because they form an azeotrope or azeotrope-like mixture with hexafluoropropylene. is there. For example, black mouthed fluoroethylene (CH = CC1F), black mouthed fluoroethylene

2

Tylene (CF = CC1F), dichlorodifluoromethane (CC1 F), etc. are hexafluoropro

2 2 2

Since the boiling point is close to that of pyrene and forms an azeotrope or azeotrope-like mixture, it is a compound that is very difficult to separate and refine.

[0005] 1, 1, 1, 2-tetrafluoroethane (CF CH F) Nyape is an important compound as a refrigerant

3 2 As a method for purifying impurities in ntafluoretane (CF CHF) etc., for example,

3 2

Methods for purification by extractive distillation and methods for removal by dehalogenation using hydrogen in the presence of a catalyst are known.

[0006] Nitrogen trifluoride (NF) and hexafluorinated tan (CF C) used as cleaning gases

3 3

F) saturated compounds such as high purity, and to reduce (purify) these chlorine-containing compounds,

Three

Various methods have been proposed and implemented to achieve high purity.

[0007] On the other hand, as a method of using hexafluoropropylene as a cleaning gas, for example,

(1) Plasma CVD reaction chamber cleaning method and plasma etching method (JP-A-9-29671),

(2) Etching gas and cleaning gas (Japanese Patent Laid-Open No. 10-27781),

(3) Process chamber cleaning method and substrate processing apparatus (Japanese Patent Laid-Open No. 2005-26409)

There are still problems and problems in the purification method and high purity of impurities in hexafluoropropylene, especially the chlorine-containing compounds that are the source of contamination.

Patent Document 1: JP-A-4-145503

Patent Document 2: JP-A-9 296271

Patent Document 3: Japanese Patent Laid-Open No. 10-27781

Patent Document 4: Japanese Patent Laid-Open No. 2005-26409

Disclosure of the invention Problems to be solved by the invention

[0008] The present invention is intended to solve the problems associated with the prior art as described above, and is a method for industrially advantageously producing high purity hexafluoropropylene, and its high purity. The purpose of the hexafluoropropylene is to provide a cleaning gas for removing deposits in a semiconductor manufacturing apparatus or a liquid crystal manufacturing apparatus. Means for solving the problem

[0009] As a result of intensive studies to solve the above problems, the present inventors have determined that crude hexafluoropropylene containing chlorine-containing compounds and / or hydrated carbons has an average pore diameter of 3.

Reduce the content of chlorine-containing compounds and Z or Hyde mouth carbons by contacting with Zeolite and Z which are 4 吸着 ~ ιιA or carbonaceous adsorbent whose average pore size is 3.5Α ~ ιιΑ It has been found that high-purity hexafluoropropylene can be obtained by combining the process and the distillation purification process, and the present invention has been completed.

That is, the present invention is configured by the following [1] to [15].

[1] A method for producing high-purity hexafluoropropylene by purifying crude hexafluoropropylene produced by thermal decomposition of chlorodifluoromethane,

(1) The crude hexafluoropropylene, zeolite having an average pore diameter of 3.4 A to llA, and Z or an adsorbent having a carbonaceous adsorbent power having an average pore diameter of 3.5 A to 11 A Reducing the content of chlorine-containing compounds and Z or hard mouth carbons in crude hexafluoropropylene, and

(2) A step of reducing the content of low boiling point components in hexafluoropropylene obtained in step (1) by distillation.

A process for producing high purity hexafluoropropylene, comprising:

[2] The chlorine-containing compound has the general formula: CH C1 F (wherein v is an integer of 1 to 4, x is an integer of 0 to 2, y is an integer of 1 to 3, z is 1 to The method for producing high-purity hexafluoropropylene according to [1] above, which is at least one compound represented by an integer of 6 and 2v≤x + y + z≤2v + 2).

[3] The chlorine-containing compound may be dichlorodifluoromethane, dichlorofluoromethane, Is at least one selected from the group consisting of difluororeomethane, chlorofluoroethylene, chlorotrifluoroethylene, chlorotetrafluoroethane, black pentafluoroethane, and black hexafluoropropane; The method for producing high-purity hexafluoropropylene as described in [1] above.

[4] The method for producing high-purity hexafluoropropylene according to the above [1], wherein the hide mouth carbon is at least one selected from the group consisting of propylene, cyclopropane and propane.

[5] The above zeolite is a zeolite having a silica Z aluminum ratio of 2.0 or less.

The method for producing high-purity hexafluoropropylene according to [1].

[6] The high-purity hexafluoropropylene according to [1], wherein the low-boiling component is at least one selected from the group consisting of nitrogen, oxygen, carbon monoxide, and carbon dioxide. Production method.

[7] [7] After distilling crude hexafluoropropylene produced by pyrolysis of chlorodifluoromethane to reduce the content of high-boiling components in the crude hexafluoropropylene, The method for producing high-purity hexafluoropropylene according to the above [1], which is used in the step (1).

[0018] [8] The high-purity hexafluoropro as described in [1] above, wherein the content of the chlorine-containing compound in the high-purity hexafluoropropylene obtained in the step (2) is 20 volppm or less. Pyrene manufacturing method.

[9] The high purity hexafluoropropylene according to the above [1], wherein the content of the hydrated carbon in the high purity hexafluoropropylene obtained in the step (2) is 30 volppm or less. Production method.

[0020] [10] The high purity hexafluoro described in [1] above, wherein the content of the low boiling component in the high purity hexafluoropropylene obtained in the step (2) is 20 volppm or less. A method for producing lopropylene.

[11] The high purity hexafluoropropylene according to the above [1], wherein the purity of the high purity hexafluoropropylene obtained in the step (2) is 99.99vo 1% or more. Production method.

[0022] [12] The above [1], wherein the high-purity hexafluoropropylene is used as a cleaning gas for removing deposits in a semiconductor manufacturing apparatus or a liquid crystal manufacturing apparatus. A method for producing high-purity hexafluoropropylene.

[0023] [13] The content of chlorine-containing compounds is 20 volppm or less, the content of hydrated carbons is 3 Ovolppm or less, and the content of low-boiling components is 20 volppm or less, and the purity is 99.99 vol% or more. A cleaning gas for removing deposits in semiconductor or liquid crystal manufacturing equipment, which is high-purity hexafluoropropylene.

[14] The high-purity hexafluoropropylene power described in [13] above, which is a high-purity hexafluoropropylene produced by the method according to any one of [1] to [12] above. Taring gas.

[0025] [15] Deposition in a semiconductor manufacturing apparatus or a liquid crystal manufacturing apparatus using the cleaning gas described in [13] above at a temperature in the range of 50 to 500 ° C and a pressure in the range of 0.05 to lMPa A cleaning method that removes objects.

The invention's effect

According to the present invention, high-purity hexafluoropropylene can be efficiently produced by a simple method, and the obtained high-purity hexafluoropropylene is used in a semiconductor manufacturing apparatus. Alternatively, it can be suitably used as a plasma cleaning gas for removing deposits in the liquid crystal manufacturing apparatus.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described in detail.

The method for producing high-purity hexafluoropropylene according to the present invention is a method for producing high-purity hexafluoropropylene by purifying crude hexafluoropropylene. Specifically, (1) the above crude hexafluoropropylene, zeolite having an average pore size of 3.4 A to llA, and Z or a carbonaceous adsorbent having an average pore size of 3.5 A to 11 A A step of reducing the content of chlorine-containing compounds and Z or hard mouth carbons in the crude hexafluoropropylene by contacting with a powerful adsorbent; (2) obtained in the above step (1) And reducing the content of low boiling components in the hexafluoropropylene by distillation.

[0029] Crude hexafluoropropylene used in the present invention is produced as a by-product in the production of tetrafluoroethylene via thermal decomposition of chlorodifluoromethane. ) And other chlorine-containing compounds, Hyde mouth fluorocarbons (HFC) It contains various impurities such as saturated and unsaturated compounds such as hydrocarbons (HC).

[0030] The chlorine-containing compound may be represented by the general formula: CH C1 F (wherein V is an integer of 1 to 4, x is an integer of 0 to 2, y is an integer of 1 to 3, and z is 1 to 6) An integer, a compound represented by 2v≤x + y + z≤2v + 2), is included, and crude hexafluoropropylene contains one or more of these compounds. Specific examples of the compound represented by the above general formula include dichlorodifluoromethane (CC1 F), dichlorofluoromethane (CHC1 F), chlorodifluoromethane (CHC1

2 2 2

F), black-opened fluoroethylene (CH = CC1F), black-opened trifluoroethylene (CF = CC1

2 2 2

F), chlorotetrafluoroethane (CF CHC1F), black-opened pentafluoroethane (CF CC1

3 3

F) and black hexafluoropropane (CF CHFCC1F) and the like. Coarsely

2 3 2

The content of the chlorine-containing compound in xafluoropropylene is preferably 0.05 vol% or less.

[0031] Examples of the above-mentioned hydrated fluorocarbons include difluoroethylene (CHF = CHF), tetrafluoroethane (CF CH F), trifluoropropene (CF CH = CH), and fluoropro.

3 2 3 2

Pens (CH CF = CH) and the like can be mentioned. The above high in crude hexafluoropropylene

3 2

The content of drofluorocarbons is preferably 0.05 vol% or less! /.

[0032] The above hydrocarbons include propylene (CH = CHCH), cyclopropane (C

2 3 3

H) and propane (CH 2 CH 2 CH 3) and the like. In crude hexafluoropropylene

6 3 2 3

It is preferable that the content of the above-mentioned hide mouth carbons is 0.05 vol% or less.

[0033] The adsorbent used in the present invention includes (1) a zeolite having an average pore diameter of 3.4 A to llA, (2) a carbonaceous adsorbent having an average pore diameter of 3.5 A to llA, or (3) the above It is a mixture of zeolite and the above carbonaceous adsorbent. Zeolite having an average pore diameter in the above range is excellent in the effect of reducing the content of impurities in crude hexafluoropropylene. In addition, the carbonaceous adsorbent having an average pore diameter in the above range is excellent in the effect of reducing the content of impurities in the crude hexafluoropropylene. Further, zeolite having a silica-Z aluminum ratio of 2.0 or less is more preferable in that the effect of reducing the content of impurities is further improved.

That is, the zeolite used in the method for producing high-purity hexafluoropropylene of the present invention has an average pore diameter of 3.4 to: L 1A, preferably 3.4 to: LOA. Is there Is good. Zeolite with an average pore size larger than 11 A increases the amount of hexafluoropropylene adsorbed, and zeolite with an average pore size smaller than 3.4 A has the ability to adsorb chlorine-containing compounds and hydrocarbons. May be smaller.

[0035] Further, the ratio of zeolite (Si) (silica) ZA1 (aluminum) is preferably 2.0 or less. When the SiZAl ratio is greater than 2, chlorine-containing compounds and hydrated carbons are selectively adsorbed. It may not be done. Zeolite includes molecular sieves 4A (MS-4A, made by Yuon Showa Co., Ltd.), molecular sieves 5A (MS-5A, made by Union Showa Co., Ltd.), molecular sieves 10X (MS-10A, made by Union Showa Co., Ltd.) and Molecular sieves 13X (MS-13X, manufactured by Union Showa Co., Ltd.) At least one kind of zeolite selected from the group that also has power is preferred.

[0036] On the other hand, activated carbon and molecular sieving carbon are known as carbonaceous adsorbents. Activated carbon is activated carbon made from coconut shell, coal, wood, etc., and carbonized at a high temperature and then activated by applying a special treatment to generate pores in the raw material, which has a wide range of uses as an excellent adsorbent. In the production method of the present invention, it is preferable to use molecular sieve having a highly controlled pore size! /, Molecular sieve carbon which is activated carbon.

[0037] The carbonaceous adsorbent has an average pore diameter of 3.5 to: L1A. The carbonaceous adsorbent having an average pore diameter larger than 11 A is adsorbed by hexafluoropropylene. Carbonaceous adsorbents with an average pore size of less than 3.5A may have a reduced ability to adsorb chlorine-containing compounds and hydrocarbons. As the carbonaceous adsorbent, molecular sieve carbon 4A (for example, manufactured by Takeda Pharmaceutical Co., Ltd.) or molecular sieve carbon 5A (for example, manufactured by Takeda Pharmaceutical Co., Ltd.) can be used in combination.

[0038] In the adsorbent containing the zeolite and the carbonaceous adsorbent, the mixing ratio of the zeolite and the carbonaceous adsorbent is not particularly limited, and the type and content of impurities in the crude hexafluoropropylene are not limited. It is set appropriately depending on the amount.

[0039] As described above, in the present invention, the content of chlorine-containing compounds and Z or hydrated carbons is reduced by bringing the adsorbent into contact with crude hexafluoropropylene. Crude hexafluoropropylene during contact of adsorbent with crude hexafluoropropylene There is no particular limitation on the state of, for example, rough hexafluoropropylene force, a method of contacting in a gas state, a method of contacting in a gas-liquid mixed state, or a method of contacting in a liquid state. Force that can be used by the method The method of contacting in the liquid state is preferable because of its high efficiency.

[0040] The method for contacting the adsorbent with the crude hexafluoropropylene is not particularly limited. For example, a known method such as a batch method or a continuous method can be used. In industry, for example, two fixed bed type adsorption towers are generally provided, and when one reaches saturation adsorption, this is switched and regenerated. The conditions for the contact treatment are not particularly limited, but the treatment temperature is preferably a low temperature. For example, a temperature range of −50 to 50 ° C. is more preferred, and a temperature range of −20 to 30 ° C. is more preferred. The treatment pressure is not particularly limited as long as the crude hexafluoropropylene is brought into contact in a liquid state as long as the pressure can be maintained in the liquid state, and when the contact is made in a gas state. Is not particularly limited, but is preferably in the range of 0.05 MPa to IMPa.

[0041] Prior to contacting with the adsorbent, the crude hexafluoropropylene is introduced into a distillation column in advance to remove low boiling components (low boiling cut) and high boiling components (high boiling cut). In this case, however, there is a possibility that low-boiling components may be mixed from the adsorbent, and it is necessary to remove low-boiling components again. Therefore, in the production method according to the present invention, (1) the crude hexafluoropropylene and the adsorbent are contacted, and then (2) the hexafluoropropylene obtained in this step (1) is distilled. And a step of reducing the content of low boiling components. In the present invention, it is preferable that the high-boiling component in the scouring and crude hexafluoropropylene is reduced in advance before the contact step (1). It is preferable to have a step of distilling crude hexafluoropropylene to reduce the content of high-boiling components in the crude hexafluoropropylene.

[0042] Examples of the low boiling point component include nitrogen, oxygen, carbon monoxide, carbon dioxide, and a mixture of two or more thereof.

[0043] Thus, by bringing crude hexafluoropropylene into contact with the adsorbent and distilling it, the contents of chlorine-containing compounds, hydrated carbons, and low-boiling components can be reduced. High purity hexafluoropropylene having a purity of 99.99 vol% or more can be obtained. this The content of chlorine-containing compounds in high-purity hexafluoropropylene is preferably 20 volppm or less. The content of hydrated carbons is more preferably 30 volppm or less. The content of hydrated carbons is more preferably 20 volppm or less. The content of low boiling components is preferably 20 volppm or less, more preferably 10 volppm or less.

[0044] Such high-purity hexafluoropropylene can be used as a cleaning gas for removing deposits in a semiconductor manufacturing apparatus or a liquid crystal manufacturing apparatus. At this time, high purity hexafluoropropylene may be used alone, but depending on the cleaning conditions, He, Ar, N

2, Ne, Kr, or group power that also has oxygen-containing compound power At least one type of dilution gas selected may be added. As the oxygen-containing compound, O

2, CO, CO

2, NO,

N 0, OF, COF and the like. It is preferable that the amount of applied force of these dilution gases is 40 vol% or less.

2 2 2

Good.

[0045] When the semiconductor manufacturing apparatus is cleaned using the cleaning gas, it may be cleaned under plasma conditions or may be cleaned under plasmaless conditions. In the case of cleaning under plus or minus conditions, the excitation source is not particularly limited as long as the above-described cleaning gas force plasma is excited, but the use of a microwave excitation source is preferable because the cleaning efficiency is good. In addition, the temperature range and pressure range in which the cleaning gas of the present invention is used are not particularly limited as long as they generate plasma. However, temperatures in the range of 50 to 500 ° C are preferred. A pressure in the lMPa range is preferred. On the other hand, when cleaning is performed under plasmaless conditions, a cleaning gas is introduced into the chamber, and preferably the pressure in the chamber is set in the range of 0.05 to lMPa. The cleaning gas is activated by heating at least one or both of them to a temperature in the range of 150 to 500 ° C., and the region force in which the chamber and other deposits are accumulated also etches the deposits. By removing it, the semiconductor manufacturing equipment can be tallyed.

[0046] [Example]

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to the examples.

[0047] [Preparation Example 1] After pyrolysis from chlorodifluoromethane (CHC1F) (pyrolysis temperature 600 ° C)

2

In the production of ethylene, the product was distilled twice to recover tetrafluoroethylene, and then crude hexafluoropropylene was obtained. This crude hexafluoropropylene was gas chromatograph [GC-14A, manufactured by Shimadzu Corporation, column: Pompack-Q (6m), manufactured by Shimadzu Corporation, measuring temperature: 80 to 200 ° C] Table 1 shows the results of the analysis.

[Example 1]

[0048] In a 1000 ml stainless steel cylinder, molecular sieve 13X (manufactured by Union Showa Co., Ltd .: average pore diameter 10 A, silica Z aluminum ratio = 0.81) 80 g and carbonaceous adsorbent (Molecular Seeding force Bonn 5A, Takeda Pharmaceutical Co., Ltd .: average pore diameter 5A) 70 g were mixed and filled, and then vacuum dried. Next, while cooling the cylinder, about 550 g of the crude hexafluoropropylene obtained in Preparation Example 1 above was charged, and stirred occasionally at room temperature, and the liquid phase portion after about 12 hours was recovered from the filling power. [Step (1)]. This liquid phase part was analyzed by a gas chromatograph [“GC-14A” manufactured by Shimadzu Corporation, column: Pompack-Q (6 m) manufactured by Shimadzu Corporation, measurement temperature: 80 to 200 ° C.]. The results are shown in Table 1.

[0049] Next, the liquid phase part obtained in the above step (1) is introduced into the distillation column, the low boiling component is extracted from the top of the distillation column (low boiling cut), and the liquid phase part is extracted from the bottom of the distillation column. [Step (2)]. This liquid phase part was analyzed by a gas chromatograph [“GC-14A” manufactured by Shimadzu Corporation, column: Pompack-Q (6 m) manufactured by Shimadzu Corporation, measurement temperature: 80 to 200 ° C.]. The results are shown in Table 1.

[0050] [Reference Example 1]

A stainless steel cylinder with a capacity of 200 ml was filled with 30 g of Molecular Sieves 13X (Union Showa Co., Ltd .: average pore diameter 10 A, silica Z aluminum ratio = 0.81) and dried in the air. Next, while cooling the cylinder, about 70 g of the crude hexafluoropropylene obtained in Preparation Example 1 was charged, stirred occasionally at room temperature, and the liquid phase part after about 12 hours of filling force was recovered. This liquid phase portion was analyzed by gas chromatography [“GC-14A” manufactured by Shimadzu Corporation, column: Pompack-Q (6 m) manufactured by Shimadzu Corporation, measurement temperature: 80 to 200 ° C.]. The results are shown in Table 1.

[0051] [Reference Example 2]

Carbonaceous adsorbent (molecular scrubbing force) on a 200 ml stainless steel cylinder —Bonn 5A, Takeda Pharmaceutical Co., Ltd .: average pore size 5A) was filled with 20 g and vacuum dried. Next, while cooling the cylinder, about 60 g of the crude hexafluoropropylene obtained in Preparation Example 1 above was charged and stirred occasionally at room temperature, and the liquid phase portion after about 12 hours was recovered with a filling power of about 12 hours. did . This liquid phase part was analyzed with a gas chromatograph [“GC-14A” manufactured by Shimadzu Corporation, column: Porapack-Q (6 m) manufactured by Shimadzu Corporation, measurement temperature: 80 to 200 ° C.]. The results are shown in Table 1.

[table 1]

table 1

(Unit: V o 1%)

Claims

Claims [1] A method for producing high-purity hexafluoropropylene by refining crude hexafluoropropylene produced by thermal decomposition of chlorodifluoromethane,

A process for producing high purity hexafluoropropylene, comprising:

[2] The chlorine-containing compound has the general formula: CH C1 F (where V is an integer of 1 to 4, X is an integer of 0 to 2, y is an integer of 1 to 3, and z is 1 to 6) The method for producing high-purity hexafluoropropylene according to claim 1, which is at least one compound represented by an integer, 2v≤x + y + z≤2v + 2).

[3] The chlorine-containing compound may be dichlorodifluoromethane, dichlorofluoromethane, chlorodifluoromethane, chlorofluoroethylene, chlorotrifluoroethylene, chlorotetrafluoroethane, chloropentafluoroethane, or chloropentafluoroethane. The method for producing high-purity hexafluoropropylene according to claim 1, wherein the method is at least one selected from the group consisting of oral hexafluoropropane.

[4] The method for producing high-purity hexafluoropropylene according to [1], wherein the hydrated carbon is at least one selected from the group consisting of propylene, cyclopropane and propane.

5. The method for producing high-purity hexafluoropropylene according to claim 1, wherein the zeolite is zeolite having a silica Z aluminum ratio of 2.0 or less.

6. The method for producing high-purity hexafluoropropylene according to claim 1, wherein the low-boiling component is at least one selected from the group consisting of nitrogen, oxygen, carbon monoxide and carbon dioxide.

[7] Steamed crude hexafluoropropylene produced by pyrolysis of chlorodifluoromethane 2. The method for producing high-purity hexafluoropropylene according to claim 1, wherein the high-boiling component content in the crude hexafluoropropylene is reduced and then subjected to the step (1). .

[8] The production of high purity hexafluoropropylene according to claim 1, wherein the content of the chlorine-containing compound in the high purity hexafluoropropylene obtained in the step (2) is 20 volppm or less. Method.

[9] The high purity hexafluoropropylene according to claim 1, wherein the content of the hydrated carbon in the high purity hexafluoropropylene obtained in the step (2) is 30 volppm or less. Production method.

[10] The production of high purity hexafluoropropylene according to claim 1, wherein the content of the low boiling component in the high purity hexafluoropropylene obtained in the step (2) is S20 volppm or less. Method.

[11] The process for producing high-purity hexafluoropropylene according to [1], wherein the purity of the high-purity hexafluoropropylene obtained in the step (2) is 99.99vol% or more.

12. The high purity hexafluoropropylene according to claim 1, wherein the high purity hexafluoropropylene is used as a cleaning gas for removing deposits in a semiconductor manufacturing apparatus or a liquid crystal manufacturing apparatus. A method for producing propylene.

[13] A high-purity hex having a chlorine-containing compound content of 20 volppm or less, a hydrated carbon content of 30 volp pm or less, and a low-boiling component content of 20 volppm or less and a purity of 99.99 vol% or more. Cleaning gas for removing deposits in semiconductor or liquid crystal manufacturing equipment, which is fluoropropylene.

[14] The cleaning gas according to claim 13, wherein the cleaning gas is high-purity hexafluoropropylene produced by the method according to any one of claims 1 to 12.

[15] Using the cleaning gas according to claim 13, the deposits in the semiconductor manufacturing apparatus or the liquid crystal manufacturing apparatus are removed at a temperature in the range of 50 to 500 ° C and a pressure in the range of 0.05 to lMPa. How to clean.