CN-121976215-A - Method for improving stability of content of nitrogen trifluoride prepared by melt electrolysis

Abstract

The invention discloses a method for improving the stability of the content of nitrogen trifluoride prepared by melting electrolysis, which belongs to the technical field of nitrogen trifluoride electrolysis, wherein the prepared metal powder is attached to the surface of a substrate in a high-temperature spray melting mode to obtain a coating electrode, and the coating electrode is used for preparing the nitrogen trifluoride by electrolysis; the substrate is nickel metal. The stability of the anode material is better than that of pure nickel serving as the anode material for preparing nitrogen trifluoride by electrolysis at different electrolysis temperatures. The price of the coating alloy material used by the invention is lower than that of pure nickel, and the coating alloy material has wide development prospect in the aspect of industrial production.

Inventors

• WANG XUYANG
• SHEN YONGMING
• SONG RUI
• ZHANG TIANKUO
• Jing Zhenlu
• YAN YUN
• SHI ZIWEI
• XU HAO

Assignees

• 中船(邯郸)派瑞特种气体股份有限公司

Dates

Publication Date

20260505

Application Date

20260116

Claims (10)

1. 1. A method for improving stability of nitrogen trifluoride content prepared by melting electrolysis is characterized in that a coating electrode is used for preparing nitrogen trifluoride by electrolysis, and the preparation method of the coating electrode comprises the following steps of attaching prepared metal powder to the surface of a substrate in a high-temperature spray melting mode to obtain the coating electrode, wherein the substrate is nickel metal.
2. 2. The method for improving the stability of the nitrogen trifluoride content by melt electrolysis according to claim 1, wherein the coated electrode is polished to obtain a coated electrode with a flat surface, and the high-temperature spray melting temperature is 1300-1800 ℃.
3. 3. The method for improving the stability of the nitrogen trifluoride content by melt electrolysis according to claim 1, wherein the metal powder is a mixture of nickel, copper, iron and manganese.
4. 4. The method for improving the stability of the content of nitrogen trifluoride produced by melt electrolysis according to claim 3, wherein the mass ratio of nickel to copper to iron to manganese in the metal powder is 30-40:20-30:10-20:10-20.
5. 5. The method for improving the stability of nitrogen trifluoride content by melt-electrolysis according to claim 1, wherein the thickness of the metal powder attached to the surface of the substrate is 5 to 8. Mu.m.
6. 6. A method for enhancing the stability of nitrogen trifluoride content in a melt-electrolytic process as claimed in claim 1, wherein the substrate uses nickel metal having a purity of greater than 99%.
7. 7. The method for improving the stability of the content of nitrogen trifluoride produced by melt electrolysis according to claim 1, wherein the coated electrode is used as an electrolysis anode and the electrolytic cathode material is an iron plate.
8. 8. The method for improving the stability of the content of nitrogen trifluoride produced by melt electrolysis according to claim 1, wherein the electrolysis voltage is 5 to 9V and the electrolysis temperature is 70 to 150 ℃.
9. 9. The method for improving the stability of the content of nitrogen trifluoride produced by melt electrolysis according to claim 1, wherein the electrolyte is molten hydrogen fluoride and ammonium bifluoride, and the mass ratio of the hydrogen fluoride to the ammonium bifluoride is 5-6:1.
10. 10. The method for improving the stability of the nitrogen trifluoride content by melt electrolysis according to claim 1, wherein the electrolysis time is not less than 24 hours, and the nitrogen trifluoride gas is collected while the electrolysis voltage is increased when the hydrogen gas volume content in the gas generated from the anode during the electrolysis is less than 2%.

Description

Method for improving stability of content of nitrogen trifluoride prepared by melt electrolysis Technical Field The invention relates to the technical field of inorganic fluoridation electrolysis, in particular to a method for improving the stability of nitrogen trifluoride content prepared by melt electrolysis. Background With the rapid development of the electronic industry, nitrogen trifluoride (Nitrogen Trifluoride, abbreviated as NF 3) gas is widely used in the electronic industry due to its excellent chemical properties. At present, the main method for preparing NF 3 gas is a molten salt electrolysis method, wherein an anode is a nickel plate or a carbon plate, a cathode is a nickel plate, a carbon plate or an iron plate, and an electrolyte is molten electrolyte. In the electrolysis process, the anode performs oxidation reaction to generate NF 3, and the cathode performs reduction reaction to generate H 2. In order to avoid the explosion of the inside of the electrolytic tank caused by the contact of H 2 generated by the anode and the cathode and NF 3, a skirtboard type electrolytic tank capable of isolating the two electrodes is generally adopted in industry. In the actual electrolysis process, nickel with the purity of 99.96% is often used as an anode material, however, the temperature imbalance of an electrolytic tank can occur in the operation process, when the temperature is too high, the nitrogen trifluoride content in the electrolytic anode gas can be reduced, the air component is increased, and when the temperature is low, the proportion is reduced due to the solidification of electrolyte, and the nitrogen trifluoride content is influenced, so that the research on the electrode structure and the material for resisting the electrolytic temperature change has important significance. Disclosure of Invention In view of the above, the invention provides a method for improving the stability of the content of nitrogen trifluoride prepared by melting electrolysis, and improving the stability of the content of nitrogen trifluoride along with the change of temperature in the electrolysis process. In order to solve the technical problems, the invention adopts the following technical scheme: the preparation method of the coating electrode comprises the step of attaching prepared metal powder to the surface of a substrate in a high-temperature spray melting mode to obtain the coating electrode, wherein the substrate is nickel metal. Preferably, the coated electrode with a flat surface is obtained after polishing treatment, and the high-temperature spray melting temperature is 1300-1800 ℃. Preferably, the metal powder is a mixture of nickel, copper, iron and manganese. Preferably, the mass ratio of nickel to copper to iron to manganese in the metal powder is 30-40:20-30:10-20:10-20. Preferably, the thickness of the metal powder attached to the surface of the substrate is 5-8 microns. Preferably, the substrate uses nickel metal having a purity of greater than 99%. Preferably, the coating electrode is used as an electrolytic anode, and the electrolytic cathode material is an iron plate. Preferably, the electrolysis voltage is 5-9V, and the electrolysis temperature is 70-150 ℃. Preferably, the electrolyte is molten hydrogen fluoride and ammonium bifluoride, and the mass ratio of the hydrogen fluoride to the ammonium bifluoride is 5-6:1. Preferably, the electrolysis time is not less than 24 hours, and the nitrogen trifluoride gas is collected when the hydrogen volume content in the gas generated by the anode during the electrolysis is less than 2%, and the electrolysis voltage is increased. The invention has the beneficial effects that: The invention creatively designs a composite alloy coating electrode based on coating structure regulation, namely realizes surface casting of alloy powder by a thermal spraying process, constructs an electrochemical reaction interface with stable performance, and forms a structure with a surface compact layer. According to the design, through a coating structure, the electrolytic stability with higher nitrogen trifluoride content can be realized in a wider temperature range, and an anode material with excellent temperature resistance is provided for an NF 3 electrolytic preparation process. Compared with the traditional pure nickel anode, the novel anode material has more stable electrolysis efficiency in a larger temperature range, can maintain more excellent electrolysis stability in a complex working environment, and effectively reduces the treatment frequency of the abnormal temperature working condition of the electrolytic tank. The electrode is used for electrolyzing nitrogen trifluoride, and the anode material has better electrolytic stability than pure nickel (purity 99.96%) material nitrogen trifluoride at different electrolytic temperatures. The price of the coating alloy material used by the invention is lower than that of pure nickel, and the industrial production h