CN-121972116-A - Device and process for green synthesis of high-purity nitric acid

Abstract

The invention discloses a device and a process for green synthesis of high-purity nitric acid. The device comprises a first reaction gas component and a second reaction gas component, wherein the first reaction gas component and the second reaction gas component are both communicated with a gas coupler, an outlet pipeline of the gas coupler is communicated with a thermal plasma reactor, an outlet pipeline of the thermal plasma reactor is communicated with a reaction tower, a bottom outlet of the reaction tower is communicated with a liquid storage tank, the first reaction gas component comprises a high-purity oxygen pipeline and a cold plasma reactor, high-purity oxygen enters the cold plasma reactor through the high-purity oxygen pipeline, gas containing ozone obtained after ozone is generated by partial oxygen in the cold plasma reactor enters the gas coupler, and the second reaction gas component comprises a high-purity nitrogen pipeline, and high-purity nitrogen enters the gas coupler through the high-purity nitrogen pipeline. The invention uses high-purity nitrogen, oxygen and water as raw materials, and adopts renewable electric power to drive plasma to directly synthesize ultra-high purity (electronic grade) nitric acid in a green way.

Inventors

• ZHANG SHUAI
• SHAO TAO
• ZHANG CHENG
• Xie Bingtao
• DOU LIGUANG
• GAO YUAN

Assignees

• 中国科学院电工研究所

Dates

Publication Date

20260505

Application Date

20260202

Claims (10)

1. 1. The device for green synthesis of the high-purity nitric acid is characterized by comprising a first reaction gas component, a second reaction gas component, a gas coupler, a thermal plasma reactor, a reaction tower and a liquid storage tank, wherein the first reaction gas component and the second reaction gas component are communicated with the gas coupler, an outlet pipeline of the gas coupler is communicated with the thermal plasma reactor, an outlet pipeline of the thermal plasma reactor is communicated with the reaction tower, and a bottom outlet of the reaction tower is communicated with the liquid storage tank; The first reaction gas component comprises a high-purity oxygen pipeline and a cold plasma reactor, high-purity oxygen enters the cold plasma reactor through the high-purity oxygen pipeline, and ozone-containing gas obtained after ozone is generated by partial oxygen in the cold plasma reactor enters the gas coupler; The second reactive gas component comprises a high purity nitrogen line through which the high purity nitrogen enters the gas coupler.
2. 2. The apparatus for green synthesis of high purity nitric acid according to claim 1, wherein the high purity oxygen pipeline, the high purity nitrogen pipeline and the outlet pipeline of the gas coupler are provided with gas control components, and the gas control components comprise a control valve and a mass flow controller.
3. 3. The apparatus for green synthesis of high purity nitric acid according to claim 1, wherein the tail gas outlet of the reaction tower is communicated with the gas coupler through a gas circulation pump.
4. 4. The apparatus for green synthesis of high purity nitric acid according to claim 3, wherein a dehydrator is provided on a pipeline through which a tail gas outlet of the reaction tower communicates with the gas coupler.
5. 5. The apparatus for synthesizing high purity nitric acid according to any of claims 1 to 4, wherein the cold plasma reactor is a dielectric barrier discharge plasma reactor, and the dielectric barrier discharge plasma reactor has a voltage of 5-25 kV and a frequency of less than 100 kHz.
6. 6. The apparatus for green synthesis of high purity nitric acid according to any of claims 1 to 4, wherein said thermal plasma reactor is a plasma reactor using metal electrodes, and said thermal plasma reactor has a voltage of 5-25 kV and a frequency of less than 100 kHz.
7. 7. A process for green synthesis of high purity nitric acid, characterized by using the apparatus for green synthesis of high purity nitric acid according to any one of claims 1 to 6, comprising the steps of: s1, generating ozone by high-purity oxygen in a cold plasma reactor; s2, mixing the mixed gas containing ozone obtained in the step S1 with high-purity nitrogen; s3, generating nitrogen oxides in the thermal plasma reactor by the mixed reaction gas obtained in the step S2; S4, dissolving the mixed product gas containing the nitrogen oxides obtained in the step S3 in water to generate high-purity nitric acid.
8. 8. The process for green synthesis of high purity nitric acid according to claim 7, wherein the concentration of ozone in the mixed reaction gas obtained in step S2 is 5-10% by volume.
9. 9. The process for green synthesis of high purity nitric acid according to claim 7, wherein the flow rate of the mixed reaction gas into the thermal plasma reactor in step S3 is 100ml/min to 1L/min.
10. 10. The process for green synthesis of high purity nitric acid according to claim 7, wherein the gas temperature of said cold plasma reactor in step S1 is 350K-450K and the gas temperature of said hot plasma reactor in step S3 is 1500K-2000K.

Description

Device and process for green synthesis of high-purity nitric acid Technical Field The invention relates to the technical field of chemical synthesis, in particular to a device and a process for green synthesis of high-purity nitric acid. Background The ultra-high purity nitric acid is mainly used in the high-tech fields of semiconductor manufacture, display panel production, photovoltaic cell processing and the like, and the high purity characteristic of the ultra-high purity nitric acid makes the ultra-high purity nitric acid an indispensable cleaning and etching material in the electronic industry. The preparation process of the ultra-high purity nitric acid mainly comprises a sub-boiling distillation method, a continuous rectification method and the like. At present, more industrial concentrated nitric acid with the concentration of more than 95% is adopted to obtain a nitric acid product with the concentration of about 95% after rectification, then ultrapure water is used for diluting the nitric acid with the required concentration of about 70%, and the electronic grade nitric acid is obtained after rectification again by taking the nitric acid as a raw material. Patent CN103072962a discloses a method for preparing electronic grade nitric acid, which adopts a polytetrafluoroethylene nanofiltration membrane filter with the diameter of 0.1 μm to 1 μm to precisely filter the low-purity nitric acid to generate the electronic grade nitric acid. Patent CN116490458a provides a process for the synthesis of nitrogen oxides, heating a gas mixture in a thermal reactor at a pressure of 10-100bar to a temperature of at least 2300K, forming a gas mixture comprising nitrogen oxides, and also provides a process for the production of nitric acid. Patent CN118949440a discloses a high-purity nitric acid purifying system, which can continuously purify low-concentration nitric acid, and can generate lower low air pressure in an evaporation tank at the same time, thereby improving the evaporation effect of nitric acid and effectively increasing the production efficiency of high purity. Patent CN120154923a provides a purification device for producing electronic grade industrial nitric acid, the heated barrel is divided into a heating zone and a feeding zone by the arc tube, so that the acid vapor on the inner wall of the arc tube exchanges heat with the reagent grade nitric acid in the feeding zone, and the heat released during condensation is absorbed by the reagent grade nitric acid in the feeding zone. Patent CN118987661B discloses a preparation device for preparing electronic grade nitric acid from raw materials and a preparation method thereof, through the arrangement of a soaking device, stirring blade rods, swivel rings, spiral blades, a preparation device main body and a heating device are matched to drive a spiral She Jiaodong nitric acid solution to be conveyed to the inner side of a filter cylinder, and the stirring effect of the spiral blades can effectively stir the heated nitric acid solution uniformly, so that the temperature distribution of the nitric acid solution is ensured to be uniform, and further the purification operation of nitric acid is facilitated. In summary, the main technical innovation for preparing electronic grade nitric acid is concentrated on the nitric acid purification technology and equipment thereof, and the technology process and the device for synthesizing the electronic grade nitric acid are lack. Disclosure of Invention In order to solve the technical problems, the invention provides a device and a process for synthesizing high-purity nitric acid in a green way. The high-purity nitric acid obtained by the method is ultra-high-purity electronic grade nitric acid. The invention uses high-purity nitrogen, oxygen and water as raw materials, and adopts renewable electric power to drive plasma to directly synthesize ultra-high purity (electronic grade) nitric acid in a green way. In order to achieve the above purpose, the invention adopts the following technical scheme: The device for green synthesis of high-purity nitric acid comprises a first reaction gas component, a second reaction gas component, a gas coupler, a thermal plasma reactor, a reaction tower and a liquid storage tank, wherein the first reaction gas component and the second reaction gas component are communicated with the gas coupler, an outlet pipeline of the gas coupler is communicated with the thermal plasma reactor, an outlet pipeline of the thermal plasma reactor is communicated with the reaction tower, and a bottom outlet of the reaction tower is communicated with the liquid storage tank; The first reaction gas component comprises a high-purity oxygen pipeline and a cold plasma reactor, wherein high-purity oxygen enters the cold plasma reactor through the high-purity oxygen pipeline, and gas containing ozone, which is obtained after part of oxygen generates ozone in the cold plasma reactor, enters the gas coupler; The