JP2000159505A - Production of halogen fluoride compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve production efficiency, reduce corrosion of a mixing part and prevent explosive reaction by adding a raw material to fluorine gas stream, evaporating the raw material, mixing both gasses and introducing the mixed gas into a reactor heated at a reaction temperature or above of both gasses. SOLUTION: A halogen other than fluorine, e.g. chlorine and/or a halogen fluoride, such as bromine trifluoride, iodine pentafluoride or the like is used as a raw material to provide the objective halogen fluoride compound such as bromine pentafluoride, iodine heptafluoride or chlorine trifluorine. Nickel, Inconel, Monel, etc., is preferable as the material for evaporator or reactor and the evaporator is equipped with a jacket type thermal insulation apparatus capable of carrying out heating and cooling. The temperature in the evaporator is controlled to nearly boiling point of the raw material and linear rate of fluorine gas is kept to <=30 cm/sec, preferably <=5 cm/sec in order to prevent rapid reaction and corrosion due to the reaction heat. The gas linear rate in the reactor is controlled to <=10 cm/sec and a baffle plate, etc., is installed in the reactor to provide a structure making stirring and mixing of the gasses efficient.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorinating agent or a fluorinated compound such as iodine heptafluoride, bromine pentafluoride, chlorine trifluoride or chlorine monofluoride useful as an etching gas or a cleaning gas in the semiconductor industry. The present invention relates to a method for producing a halogen compound.

[0002]

2. Description of the Related Art As a method for producing a fluorinated halogen compound such as bromine pentafluoride, chlorine trifluoride or chlorine monofluoride, an equivalent number of halogen elements corresponding to fluorine is vaporized. It is known that the reaction is carried out in a liquid phase or a liquid phase [for example, L. Stein: J. Am. Chem. Soc., 8
1 , 1269 (1959), HEKluksdahl, GHCady: J. Am. Chem. So
c., 81, 5285 (1959), JWMellor (ed): AComprehensive Tre
atise on Inorganic and Theoretical Chemistry, Suppl
ement II, part I, (1956), 147]. However, in the case of a gas phase reaction, the reaction temperature must be 200 ° C or higher. And sometimes reaches a glowing state, resulting in severe reactor corrosion. In the case of a liquid phase reaction, there is a high risk that fluorine dissolved in the raw material solution reacts explosively. Furthermore, as a method for producing a fluorinated halogen compound oxidized to the highest valence, such as iodine heptafluoride, fluorine is blown into a heated solution of iodine pentafluoride, and iodine pentafluoride and fluorine entrained in the fluorine are mixed. It is known to lead to a reaction zone at 300 ° C. to obtain iodine heptafluoride [eg WCSchumb, MALynch Jr., Ind. Eng. Chem., 42, 13
83 (1950)]. In this case, there is a problem that fluorine dissolved in iodine pentafluoride reacts explosively or corrosion of a container holding a high-temperature iodine pentafluoride solution occurs. I can't say. It is also necessary to stop the reaction to replenish the consumed iodine pentafluoride.
Furthermore, in the case of production by a direct reaction between iodine and fluorine, the reaction heat is large, the control of the reaction is difficult, and the handling method is not easy because iodine is a solid.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to safely and easily continuously and efficiently convert fluorinated halogen compounds such as iodine heptafluoride, bromine pentafluoride, chlorine trifluoride and chlorine monofluoride. It is to manufacture well. The present invention is an invention made to solve the above-mentioned problem. That is, according to the present invention, after halogens other than fluorine and / or fluorinated halogens are added to a fluorine gas stream and evaporated and mixed, the mixture is introduced into a reactor heated to a temperature equal to or higher than the reaction temperature of both to react the two. A method for producing a fluorinated halogen compound, characterized in that: In the present invention, a reaction raw material such as iodine pentafluoride is added to a fluorine gas stream which flows slowly and is heated to near the boiling point of the raw material (halogen element other than fluorine or fluorinated halogen), and is evaporated and mixed. By introducing these gases into a high-temperature reactor and reacting them, the target substance such as iodine heptafluoride can be efficiently and continuously obtained. Thus, the temperature of the mixing section of the raw material and the fluorine gas can be suppressed to about the boiling point of the raw material (100 to 130 ° C.), and the corrosion of the mixing section can be greatly reduced. In addition, the mixing part and the reaction part of the raw material and the fluorine gas are separated, and the explosive reaction can be prevented by sufficiently stirring and mixing and supplying the stoichiometric amount of the raw material which is slowly heated to the reactor. it can.

[0004]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The present invention is not only iodine heptafluoride, other fluorinated halides, for example, bromine pentafluoride, chlorine trifluoride,
It can also be used effectively for the production method of chlorine monofluoride and the like. The production apparatus used in the present invention is provided with an evaporator (a preheater may be used in the case of chlorine) for evaporating raw materials such as bromine trifluoride, iodine pentafluoride, and bromine, and mixing the raw material with fluorine gas. It consists of two reactors for performing the fluorination reaction.
As the material of the evaporator and the reactor, nickel, inconel, hastelloy, monel, aluminum, copper, iron and the like can be used, but nickel, inconel, monel and the like are most preferable.

It is desirable that the evaporator is provided with a jacket type heat retaining device capable of heating and cooling so as to maintain a constant temperature. The linear velocity of fluorine gas in the evaporator is 30cm / se
c. It is necessary to keep the pressure below 5 cm / sec. Otherwise, a sharp reaction between the fluorine and the raw material occurs,
The heat of reaction may cause corrosion of the evaporator.

[0006] On the other hand, the gas linear velocity in the reactor is set so as to obtain a residence time required for the reaction, but is set at 10 cm / sec.
It is desirable to hold down below. Also, in the reactor,
Preferably, the structure is such that the gas can be efficiently stirred and mixed, and for example, a jammer plate or the like is provided.

[0007]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. Example 1 (Production of chlorine trifluoride) Using a reactor shown in FIG. 1, fluorine gas was introduced into a nickel preheater set at 100 ° C. at a linear velocity of 1 cm / sec. 0.31cm / sec chlorine gas in the air flow.
It was introduced so as to have a linear velocity of. 300 ° C
At a linear velocity of 2 cm / sec. 8
The reaction was continued for a period of time, and the gas discharged from the reactor was collected by cooling and analyzed. As a result, chlorine trifluoride was obtained at a chlorine-based yield of 95%. Even after the reaction was performed for 1000 hours, no corrosion phenomenon was observed in the evaporator and the reactor, no explosion was observed, and a stable reaction was performed.

Comparative Example 1 The reaction was carried out under the same conditions as in Example 1 except that the preheater was omitted. In this case, immediately after the start of the reaction, the reaction temperature rose rapidly, and the temperature of the mixed portion of chlorine and fluorine rose to a red-hot state. Further, the reaction did not continue smoothly, and the pressure and flow rate in the system greatly changed due to hunting, and the reaction could not be continued.

Example 2 (Production of bromine pentafluoride) Fluorine gas was introduced into a nickel evaporator set at 100 ° C.
m / sec. was introduced at a linear velocity, and bromine was dropped into the air stream at a linear velocity of 0.35 cm / sec. This mixed gas was introduced into the reactor heated to 200 ° C. at a linear velocity of 3.5 cm / sec. The reaction was continued for 6 hours, and the gas discharged from the reactor was collected by cooling and analyzed. As a result, bromine pentafluoride was obtained with a bromine-based yield of 90%. Also in this case, even after the reaction was performed for 30 hours, no corrosion phenomenon and no explosion phenomenon were observed in the evaporator and the reactor, and a stable reaction could be performed. In this case, similar results were obtained when bromine trifluoride was dropped into a fluorine gas stream in a nickel evaporator set at 130 ° C. instead of bromine.

Comparative Example 2 The reaction was carried out under the same conditions as in Example 2 except that the evaporator was removed. At this time, 30 minutes after the start of the reaction, the vicinity of the bromine inlet rose to a red-hot state, and the reaction could not be continued.

Example 3 (Production of iodine heptafluoride) 2 c of fluorine gas was placed in a nickel evaporator set at 120 ° C.
m / sec. was introduced at a linear velocity, and iodine pentafluoride was dropped into this gas stream at a linear velocity of 1.9 cm / sec. 5.6cm into the reactor heated to 300 ℃
/ Sec. At a linear velocity. The reaction was carried out for 8 hours, and the gas discharged from the reactor was collected by cooling and analyzed. As a result, iodine heptafluoride was obtained in a yield of 60% based on iodine pentafluoride. Also in this case, even after the reaction was performed for 50 hours, no corrosion phenomenon and no explosion phenomenon were observed in the evaporator and the reactor, and a stable reaction could be performed.

Comparative Example 3 The reaction was carried out under the same conditions as in Example 3 except that the evaporator was removed. Also in this case, immediately after the start of the reaction, the vicinity of the iodine pentafluoride inlet rose to a red-hot state, and the reaction could not be continued.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a reaction apparatus used in the method of the present invention.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ryo Mogi 1497 Shibukawa-shi, Gunma Kanto Denka Kogyo Co., Ltd.Fluorine Research Institute (72) Inventor Takashi Iida 1497 Shibukawa-shi Gunma Prefecture Kanto Denka Kogyo Co., Ltd. 72) Inventor Masamichi Sato 1497, Shibukawa-shi, Gunma F-term in Kanto Denka Kogyo Co., Ltd. Fluorine Research Laboratory 5F004 DA00

Claims (1)

[Claims] 1. A halogen gas other than fluorine and / or a fluorinated halogen are added to a fluorine gas stream, evaporated and mixed, and then introduced into a reactor heated to a temperature equal to or higher than the reaction temperature of the two to react them. A process for producing a fluorinated halogen compound.