Krypton difluoride and preparation method thereof

Abstract

The invention discloses krypton difluoride and a preparation method thereof, and belongs to the technical field of synthesis of rare gas compounds. The preparation method of the krypton difluoride comprises the following steps: by taking krypton gas and a fluorinating agent as raw materials, carrying out staged catalytic reaction at the temperature of 50 DEG C below zero to 0 DEG C under the pressure of 0.5 MPa to 2 MPa, so as to prepare the krypton difluoride. In addition, the invention further provides krypton difluoride which is prepared by the preparation method. According to the method, the fluorinating agent is taken as the raw material, the activation energy is reduced synergistically, the temperature is controlled by stages, the thermal decomposition of the product is inhibited, the traditional pure fluorine system is replaced, the safety is improved, and the krypton difluoride is mildly prepared at a relatively high temperature.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rare gas compound synthesis, and particularly relates to krypton difluoride and a preparation method thereof. BACKGROUND

[0002] As a unique inorganic compound, krypton difluoride (KrF2) occupies an irreplaceable position in modern industry and high-tech fields. Its strong oxidizing property and excellent laser gain characteristics make it an important laser medium and high-efficiency oxidizing agent, and it is widely used in excimer laser devices, semiconductor material etching, high-energy chemical synthesis and other key fields. In semiconductor manufacturing, excimer lasers based on krypton difluoride can achieve high-precision microprocessing, meeting the technical needs of advanced chip manufacturing. In the field of aerospace propulsion, its strong oxidizing property can significantly improve fuel combustion efficiency. Therefore, the stable supply of krypton difluoride plays an important supporting role in the development of related industries. Currently, the traditional preparation process of krypton difluoride is mainly based on the principle of gas discharge synthesis. This method is clearly described in Japanese patent JP2000128709A. The core of the method is to mix krypton (Kr) and fluorine gas (F2) in a specific ratio, and then place them in an ultra-low temperature environment of -196℃. A high-voltage electric field is applied to initiate a gas discharge reaction, which helps the two inert gases to overcome the reaction energy barrier and generate krypton difluoride. However, this process has many inherent defects, which seriously restrict its industrial application scale and safety. First, the ultra-low temperature condition of -196℃ requires the use of a large-scale liquid nitrogen refrigeration system, which has high equipment investment cost and huge energy consumption. The energy loss rate during production is more than 40%. Second, fluorine gas is a highly toxic and strongly corrosive gas, which has a high risk of leakage during storage, transportation and reaction. The sealing requirements for the operating environment are extremely strict, and complex anti-leakage and emergency treatment devices need to be provided. To overcome the drawbacks of the traditional process, researchers have conducted a lot of improvement research. Chinese patent CN101234567B discloses a preparation method using xenon difluoride (XeF2) as a catalyst. This method uses the catalytic activity of xenon difluoride to reduce the activation energy of the reaction, which raises the reaction temperature compared to the traditional process. However, it still needs to be maintained at a low temperature below -100℃, and the temperature has not been significantly improved. In summary, the existing preparation process of krypton difluoride still has problems such as harsh reaction conditions, low safety, high energy consumption and cost. Developing a preparation process with milder reaction conditions and safer operation has important practical value and practical significance for promoting the development of krypton difluoride-related industries. SUMMARY

[0003] The present application aims to overcome the above technical deficiencies, and provide a krypton difluoride and a preparation method thereof, which solves the technical problem of how to prepare krypton difluoride at a higher temperature and in a mild manner in the prior art.

[0004] To achieve the above technical purposes, the technical scheme of the present application provides a preparation method of krypton difluoride, comprising the following steps: using krypton gas and a fluorinating agent as raw materials, and preparing the krypton difluoride by catalytic reaction in stages under the conditions of-50~0℃ and 0.5~2MPa pressure.

[0005] In any embodiment, the molar ratio of the krypton gas to the fluorinating agent is 1:(1.2~1.8).

[0006] In any embodiment, the fluorinating agent is a mixture of XeF2 and ClF3.

[0007] In any embodiment, the molar ratio of XeF2 to ClF3 in the mixture is 1:(0.5~2).

[0008] In any embodiment, the method further comprises a pre-activation treatment of the fluorinating agent: ball milling the fluorinating agent for 20~40 minutes.

[0009] In any embodiment, the catalytic reaction in stages comprises: first catalytic reaction at-50~-30℃, and then heating to-20~0℃ for continuous catalytic reaction.

[0010] In any embodiment, the time for catalytic reaction at-50~-30℃ is 2~4 hours, and the time for catalytic reaction at-20~0℃ is 1~3 hours.

[0011] In any embodiment, the pressure of 0.5~2MPa is adjusted by dilution with nitrogen or argon.

[0012] In addition, the present application also provides a krypton difluoride prepared by the above preparation method.

[0013] Compared with the prior art, the present application has the following beneficial effects: the present application uses a fluorinating agent as raw material, cooperatively reduces the activation energy, controls the temperature in stages, inhibits the thermal decomposition of the product, replaces the traditional pure fluorine gas system, improves the safety, and realizes the preparation of krypton difluoride at a higher temperature and in a mild manner. BRIEF DESCRIPTION OF DRAWINGS

[0014] Fig. 1 is a photo of the krypton difluoride prepared in Example 1 of the present application.

[0015] Fig. 2 is a photo of the krypton difluoride prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0016] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60~120 and 80~110 are listed for a specific parameter, it is also expected that ranges of 60~110 and 80~120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1~3, 1~4, 1~5, 2~3, 2~4, and 2~5. In this application, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0~5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0017] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0018] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0019] This specific embodiment provides a method for preparing krypton difluoride, comprising the following steps: pre-activating the fluorinating agent: ball milling the fluorinating agent for 20-40 minutes; using krypton gas and the activated fluorinating agent as raw materials, performing a staged catalytic reaction at -50~0℃ and 0.5~2MPa pressure to obtain the krypton difluoride; the molar ratio of the krypton gas to the fluorinating agent is 1:(1.2~1.8); the fluorinating agent is a mixture of XeF2 and ClF3; the molar ratio of XeF2 to ClF3 in the mixture is 1:(0.5~2); adjusting the pressure to 0.5~2MPa by dilution with nitrogen or argon gas.

[0020] In some embodiments, the staged catalytic reaction includes first catalyzing at -50 to -30°C for 2 to 4 hours, and then raising the temperature to -20 to 0°C to continue the catalytic reaction for 1 to 3 hours.

[0021] This specific embodiment also proposes a krypton difluoride, which is prepared by the above preparation method.

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] In this invention, the terms "some embodiments," "this embodiment," and examples are used to describe a subset of all possible embodiments. However, it is understood that "some embodiments" can be the same subset or different subsets of all possible embodiments and can be combined with each other without conflict.

[0024] If the application documents contain similar descriptions such as "first / second", the following explanation shall be added: In the following description, the terms "first / second / third" are used only to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first / second / third" may be interchanged in a specific order or sequence where permitted, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein.

[0025] In this embodiment, the term "and / or" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, object A and / or object B can represent three situations: object A exists alone, object A and object B exist simultaneously, and object B exists alone.

[0026] The following describes embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all conventional products that can be obtained commercially.

[0027] Example 1 This embodiment proposes a krypton difluoride, prepared by the following steps: Pre-activation treatment of the fluorinating agent: ball milling the fluorinating agent for 30 minutes; using krypton gas and the activated fluorinating agent as raw materials, a constant-temperature catalytic reaction is first carried out at -40°C for 3 hours under a pressure of 1.2 MPa, followed by a further catalytic reaction at -10°C for 2 hours to obtain the krypton difluoride; the molar ratio of krypton gas to the fluorinating agent is 1:1.5; the fluorinating agent is a mixture of XeF2 and ClF3; the molar ratio of XeF2 to ClF3 in the mixture is 1:1; the pressure is adjusted to 1.2 MPa by dilution with nitrogen gas. The obtained KrF2 purity is 97.3%, and the yield based on krypton gas is 55.2%. Figs. 1-2 It can be seen that the prepared KrF2 is a white powder.

[0028] Example 2 This embodiment presents a krypton difluoride prepared by the following steps: Pre-activation treatment of the fluorinating agent: ball milling the fluorinating agent for 20 minutes; using krypton gas and the activated fluorinating agent as raw materials, a constant-temperature catalytic reaction is first carried out at -35°C for 4 hours under a pressure of 1.2 MPa, followed by a further catalytic reaction at 0°C for 1 hour to obtain the krypton difluoride; the molar ratio of the krypton gas to the fluorinating agent is 1:1.2; the fluorinating agent is a mixture of XeF2 and ClF3; the molar ratio of XeF2 to ClF3 in the mixture is 1:0.8; the pressure is adjusted to 1.2 MPa by diluting with nitrogen gas. The obtained KrF2 purity is 96.7%, and the yield based on krypton gas is 56.5%.

[0029] Example 3 This embodiment presents a krypton difluoride prepared by the following steps: Pre-activation treatment of the fluorinating agent: ball milling the fluorinating agent for 20 minutes; using krypton gas and the activated fluorinating agent as raw materials, a constant-temperature catalytic reaction is first carried out at -50°C for 4 hours under a pressure of 1.5 MPa, followed by a further catalytic reaction at -20°C for 1 hour to obtain the krypton difluoride; the molar ratio of krypton gas to the fluorinating agent is 1:1.8; the fluorinating agent is a mixture of XeF2 and ClF3; the molar ratio of XeF2 to ClF3 in the mixture is 1:1.5; the pressure is adjusted to 1.5 MPa by diluting with nitrogen gas. The obtained KrF2 purity is 96.9%, and the yield based on krypton gas is 55.8%.

[0030] Example 4 This embodiment presents a krypton difluoride preparation method. The difference between this method and Example 1 is that nitrogen is replaced with argon gas; all other process conditions and raw materials are the same as in Example 1. The obtained KrF2 has a purity of 96.1%, and the yield is 53.9% based on krypton gas.

[0031] Comparative Example 1 The difference between the preparation method of krypton difluoride in this comparative example and that in Example 1 is that only XeF2 is used as the fluorinating agent. An equal amount of XeF2 is used to replace the total amount of XeF2 and ClF3 used in Example 1. All other process conditions and raw materials are the same as in Example 1. The purity of the obtained KrF2 is 82.4%, and the yield is 43.9% based on krypton gas.

[0032] Comparative Example 2 The difference between the preparation method of krypton difluoride in this comparative example and that in Example 1 is that only ClF3 is used as the fluorinating agent. An equal amount of ClF3 is used to replace the total amount of XeF2 and ClF3 used in Example 1. All other process conditions and raw materials are the same as in Example 1. The purity of the obtained KrF2 is 85.6%, and the yield is 52.6% based on krypton gas.

[0033] Comparative Example 3 The difference between the preparation method of krypton difluoride in this comparative example and that in Example 1 is that the reaction is carried out at the same temperature throughout. Specifically, the reaction is carried out at a constant temperature of -40°C for 5 hours under a pressure of 1.2 MPa. Other raw materials and process conditions are the same as in Example 1. The purity of the obtained KrF2 is 91.2%, and the yield is 48.7% based on krypton gas.

[0034] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing krypton difluoride, characterized in that, Includes the following steps: The krypton difluoride was prepared by a staged catalytic reaction using krypton gas and a fluorinating agent as raw materials at -50 to 0°C and 0.5 to 2 MPa pressure.

2. The method for preparing krypton difluoride according to claim 1, characterized in that, The molar ratio of krypton to the fluorinating agent is 1:(1.2~1.8).

3. The method for preparing krypton difluoride according to claim 2, characterized in that, The fluorinating agent is a mixture of XeF2 and ClF3.

4. The method for preparing krypton difluoride according to claim 3, characterized in that, The molar ratio of XeF2 to ClF3 in the mixture is 1:(0.5~2).

5. The method for preparing krypton difluoride according to claim 1, characterized in that, It also includes pre-activating the fluorinating agent: ball milling the fluorinating agent for 20-40 minutes.

6. The method for preparing krypton difluoride according to claim 1, characterized in that, The staged catalytic reaction includes: first, catalytic reaction at -50~-30℃, and then catalytic reaction continued at -20~0℃.

7. The method for preparing krypton difluoride according to claim 6, characterized in that, The catalytic reaction time is 2 to 4 hours at -50 to -30℃ and 1 to 3 hours at -20 to 0℃.

8. The method for preparing krypton difluoride according to claim 6, characterized in that, The pressure is adjusted to 0.5~2MPa by diluting with nitrogen or argon gas.

9. A krypton difluoride, characterized in that, It is prepared by the preparation method according to any one of claims 1-8.

Images