Production device of electronic-grade nitric oxide

Abstract

The utility model discloses an electronic grade nitric oxide production device which comprises a sulfuric acid storage tank and a reactor, the reactor is connected with a bag type filter A and a bag type filter B in parallel, and the bag type filter A, the bag type filter B and a reactor pipeline circulate through a pump and are connected with a nitrogen pipeline and an emptying vacuum pipeline. An outlet pipeline at the upper end of the reactor is connected with the first rectifying tower and the second rectifying tower, and electronic-grade nitric oxide is extracted from the second rectifying tower and filled into a steel cylinder. Compared with a traditional reaction kettle using stirring blades, sodium sulfate supersaturated crystals produced through reaction are effectively separated through circulation of a pump and a bag type filter, generation of waste water is reduced, meanwhile, the reaction speed in the reactor is increased, the problems that a large number of solids are generated in the reaction, and the stirring blades are high in energy consumption and damaged are solved, and the reaction kettle is worthy of industrial popularization.

Description

Technical Field

[0001] This utility model relates to a production device for electronic-grade nitric oxide, belonging to the field of electronic specialty gases. Background Technology

[0002] Nitric oxide (NO) is a nitrogen oxide compound, a colorless, odorless, and highly toxic gas that is poorly soluble in water. In chip manufacturing processes, NO has multiple functions and applications, including cleaning, deposition, and surface treatment. Its high reactivity, gaseous state, and biological activity make it an indispensable raw material in chip manufacturing. By utilizing NO rationally, chip quality and performance can be improved, promoting the continuous development and innovation of chip manufacturing technology. Therefore, with the development of semiconductors, the purity requirements for NO are becoming increasingly stringent.

[0003] Currently, in the market, electronic-grade nitric oxide purification methods utilize the reaction of sodium nitrite and dilute sulfuric acid to prepare nitric oxide raw materials. Because the reaction involves the dissolution of solid sodium nitrate, traditional reactors use stirring blades to accelerate dissolution and ensure a complete reaction. However, since the concentration of the produced sodium sulfate supersaturated crystals is lower than that of sodium nitrite, the large amount of supersaturated sodium sulfate crystals increases the load on the stirring blades. Traditional processes use water to dissolve the supersaturated sodium sulfate crystals, thus reducing the load on the stirring blades. However, this method generates a large amount of wastewater and negatively impacts the reaction rate, increasing production costs. Furthermore, traditional nitric oxide purification technologies employ adsorption processes to remove gaseous impurities such as moisture, nitrogen dioxide, and nitrous oxide, which cannot meet the demands of large-scale production.

[0004] In summary, existing processes for preparing raw material nitric oxide suffer from problems such as high load on the stirring blades and excessive wastewater, and the adsorption and purification process for nitric oxide cannot be used for large-scale production. Therefore, it is necessary to develop a stable, low-load, low-wastewater, and low-cost large-scale continuous production device and method for electronic-grade nitric oxide.

[0005] The pump circulation and capsule filter effectively separate the supersaturated sodium sulfate crystals produced by the reaction, reducing wastewater generation and increasing the reaction rate in the reactor. This solves the problem of high energy consumption and damage to the stirring blades caused by the generation of a large amount of solids in the reaction, and is worthy of industry promotion. Summary of the Invention

[0006] The purpose of this invention is to overcome the above-mentioned shortcomings and provide a production device for electronic-grade nitric oxide, which achieves continuous large-scale production of electronic-grade nitric oxide with less wastewater, high reaction rate, low cost, and comprehensive resource utilization.

[0007] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows:

[0008] An apparatus for producing electronic-grade nitric oxide, the apparatus comprising a sulfuric acid storage tank, a reactor, a capsule filter A, and a capsule filter B;

[0009] The tops of capsule filter A and capsule filter B are connected in parallel via pipes, and the bottoms of capsule filter A and capsule filter B are connected in parallel via pipes, allowing capsule filter A and capsule filter B to be used interchangeably.

[0010] The bottom outlet of the reactor is connected to a circulation pipeline via a liquid phase feed pump and a pipeline that is connected in parallel to the top of capsule filter A and capsule filter B.

[0011] The pipes connected in parallel at the bottom of capsule filters A and B are then connected to the lower inlet of the reactor to form a circulation pipeline;

[0012] The reactor's upper outlet pipeline is connected to the first and second distillation columns, and electronic-grade nitric oxide is collected from the second distillation column and filled into steel cylinders.

[0013] The reactor is equipped with a sulfuric acid storage tank and a water inlet pipeline at the top, and a sulfuric acid metering pump is connected to the sulfuric acid pipeline.

[0014] Valves are installed on the pipes that are connected in parallel at the top of the capsule filter A and capsule filter B, namely valve three for capsule filter A and valve three for capsule filter B.

[0015] Valves are installed on the liquid phase pipelines that are connected in parallel at the bottom of capsule filter A and capsule filter B, namely valve four for capsule filter A and valve four for capsule filter B.

[0016] The filter membranes of the capsule filter A and capsule filter B are made of PTFE, ceramic, or 316L metal.

[0017] A nitrogen valve is installed at the top of the reactor; a gas phase valve is installed on the pipeline from the top of the reactor to the first distillation column, and a gas phase feed pump is installed on the pipeline.

[0018] The capsule filter A and capsule filter B are respectively provided with nitrogen inlet pipes at their top, namely nitrogen inlet pipe A-1 and nitrogen inlet pipe B-1, and respectively are provided with valves, namely nitrogen inlet pipe A valve 2 and nitrogen inlet pipe B valve 2.

[0019] The capsule filter A and capsule filter B are respectively provided with nitrogen output pipes at the bottom, namely nitrogen output pipe A6 and nitrogen output pipe B6, and valves are respectively provided on nitrogen output pipe A6 and nitrogen output pipe B6, namely nitrogen output pipe A valve 5 and nitrogen output pipe B valve 5.

[0020] Nitrogen output pipe A and nitrogen output pipe B merge and connect to the vacuum pipe; the bottom of the reactor is connected to the vent pipe, which is equipped with a vent pipe vacuum pump, and the end of the vent pipe is connected to the waste liquid tank.

[0021] The first distillation column is connected to heat exchanger one, and the second distillation column is connected to heat exchanger two. The heat exchangers use liquid nitrogen as a refrigerant.

[0022] Based on the above technical solution, this utility model also provides a method for producing electronic-grade nitric oxide, which is implemented using the aforementioned electronic-grade nitric oxide production apparatus. The production method includes the following steps:

[0023] S1: After evacuating all components in the electronic-grade nitric oxide production unit, the entire production unit is purged with nitrogen.

[0024] S2: Add solid NaNO2 to the reactor, add water, and then add dilute sulfuric acid to the reactor to carry out the reaction;

[0025] S3: When the pressure inside the reactor is constant, open the gas phase valve 2 connected to the distillation column, start the liquid phase feed pump, open the valves 3 and 4 of the capsule filter A, so that the reactor and capsule reactor A form a circulation and a pressure difference is formed at both ends of the capsule reactor A. First close the valve 3 of the capsule filter A, open the valves 3 and 4 of the capsule filter B, and finally close the valve 4 of the capsule filter A. Open the valve 5 of the nitrogen output pipe A, start the vacuum pump of the vent pipe, evacuate the capsule filter A, so that the Na2SO4 supersaturated crystals precipitated on the filter screen fall to the bottom of the capsule filter and the Na2SO4 supersaturated crystals are discharged through the vent pipe. Close the valve 5 of the nitrogen output pipe A.

[0026] S4: After the pressure difference is achieved at both ends of the capsule reactor B, first close valve three of the capsule filter B, open valve three and valve four of the capsule filter A, and finally close valve four of the capsule filter B. Open valve five of the nitrogen output pipe B, start the vacuum pump of the vent pipe, and evacuate the capsule filter B to make the Na2SO4 supersaturated crystals precipitated on the filter screen fall to the bottom of the capsule filter. Expel the Na2SO4 supersaturated crystals through the vent pipe, close valve five of the nitrogen output pipe B, and repeat the operation of S3 to switch to capsule filter A.

[0027] S5: Nitric oxide gas produced by the reactor enters the first and second distillation columns in sequence. Electronic-grade nitric oxide is collected from the second distillation column and filled into steel cylinders.

[0028] S6: After nitric oxide is no longer generated in the reactor, switch to the reactor to start the S2-S5 reaction process.

[0029] The reactor can also be equipped with another standby reactor, so that one reactor can be used while the other is in operation, and they can be switched between each other. Then, step S6 is as follows: after nitric oxide is no longer generated in the reactor, switch to the standby reactor to start the reaction process of S2-S5, open the bottom valve of the reactor, start the vacuum pump 7, and discharge the reactants in the reactor to the waste liquid tank through the drain pipe.

[0030] In step S1, the mass ratio of NaNO2 solid, water, and dilute sulfuric acid is 1-1.5:1.5-2:0.5-1.5; the mass concentration of the dilute sulfuric acid is 50-70%. In some embodiments, the mass concentration of the dilute sulfuric acid is 60%.

[0031] The pressure difference obtained in S2 and S3 is 0.4-1.0 MPa, and more preferably 0.5-0.8 MPa.

[0032] This pressure difference is to protect the filter. Too much pressure will cause the filter membrane to break, while too little pressure will result in low efficiency.

[0033] In the preferred embodiment, the number of trays in the first distillation column is 25 to 40, more preferably 28 to 35, and the feed tray is located at the 18th to 22nd tray from the bottom, more preferably 19 to 21st tray.

[0034] In the preferred embodiment, the number of trays in the second distillation column is 28 to 40, more preferably 28 to 35, and the feed tray is located at the 18th to 22nd tray from the bottom, and more preferably 19 to 21st tray.

[0035] In the preferred embodiment, the top temperature of the first distillation column is -115~-105℃, more preferably -110~-106℃, the bottom temperature is -108~-100℃, more preferably -109~-103℃, and the mass reflux ratio of the first distillation column is 1.5~5, more preferably 2~4.

[0036] In the preferred embodiment, the top temperature of the second distillation column is -140~-128℃, more preferably -138~-130℃, the bottom temperature is -110~-100℃, more preferably -108~-105℃, and the mass reflux ratio of the first distillation column is 20~35, more preferably 22~28.

[0037] Compared with the prior art, this utility model has the following advantages:

[0038] 1. This invention uses sodium nitrite and dilute sulfuric acid to prepare nitric oxide. By establishing a reactor-pump-bladder filter circulation system, replacing traditional stirring blades, the reactants are brought into full contact, effectively mixing them uniformly. Simultaneously, the use of a blade filter effectively removes the low-solidity supersaturated sodium sulfate crystals generated during the reaction, reducing the load on the stirring blades and preventing the supersaturated sodium sulfate crystals from adsorbing onto the blade surface, thus solving the problem of easily damaged stirring blades. The switching between blade filters A and B ensures effective removal of supersaturated sodium sulfate crystals, avoiding the traditional process of dissolving supersaturated sodium sulfate crystals with water, which not only reduces the reaction rate but also generates a large amount of saline wastewater requiring treatment, increasing production costs. The use of blade filters and the switching between blade filters A and B ensure the continuity of the production process.

[0039] 2. This invention provides a method for purifying nitric oxide using distillation to produce electronic-grade nitric oxide with a purity of 99.9995% or higher. The method employs a double-tower distillation process with liquid nitrogen as the coolant, effectively removing gaseous impurities such as moisture, nitrogen dioxide, nitrous oxide, nitrogen, and oxygen from crude nitric oxide prepared from sodium nitrite and dilute sulfuric acid. This effectively solves the problem that traditional adsorbent purification processes cannot meet the requirements of large-scale industrial production, and also addresses the issues of cumbersome and complex adsorbent activation processes. Attached Figure Description

[0040] Figure 1 This is a structural diagram of an electronic-grade nitric oxide apparatus.

[0041] Figure 2 This is a schematic diagram of the structure of part A of the capsule filter.

[0042] The system includes: sulfuric acid storage tank 1, water inlet pipe 2, reactor 3, liquid phase feed pump 4, capsule filter A5, nitrogen inlet pipe A-5-1, pipe A valve 2 5-2, capsule filter A valve 3 5-3, capsule filter A valve 4 5-4, nitrogen outlet pipe A valve 5-5, nitrogen outlet pipe A 6 5-6, nitrogen inlet pipe B-6-1, pipe B valve 2 6-2, capsule filter B valve 3 6-3, capsule filter B valve 4 6-4, nitrogen outlet pipe B valve 5 6-5, nitrogen outlet pipe B 6 6-6, capsule filter B 6, vent pipe, vacuum pump 7, first distillation column 8, heat exchanger 1 9, second distillation column 10, heat exchanger 2 11, liquid phase pipe 1 12, vent pipe 13, gas phase valve 2 14, gas phase feed pump 15, and nitrogen valve 1 16. Detailed Implementation

[0043] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0044] Example 1

[0045] Figure 1 A structural diagram of an apparatus for directly producing electronic-grade hydrochloric acid from hydrogen chloride.

[0046] An apparatus for producing electronic-grade nitric oxide, the apparatus comprising a sulfuric acid storage tank 1, a reactor 3, a capsule filter A 5, and a capsule filter B 6;

[0047] The tops of capsule filter A5 and capsule filter B6 are connected in parallel via pipes, and the bottoms of capsule filter A5 and capsule filter B6 are connected in parallel via pipes, allowing capsule filter A5 and capsule filter B6 to be used interchangeably.

[0048] The bottom outlet of reactor 3 is connected to a circulation pipeline via a liquid phase feed pump 4 and a pipeline that is connected in parallel to the top of capsule filter A 5 and capsule filter B 6.

[0049] The tubing 12, which is connected in parallel at the bottom of the capsule filter A 5 and capsule filter B 6, is then connected to the lower inlet of the reactor 3 to form a circulation pipeline;

[0050] The upper outlet pipe of the reactor 3 is connected to the first distillation column 8 and the second distillation column 10, and electronic-grade nitric oxide is collected from the second distillation column 10 and filled into a steel cylinder.

[0051] The top of reactor 3 is equipped with a sulfuric acid storage tank 1 and a water inlet pipe 2;

[0052] Valves are installed on the pipes that are connected in parallel at the top of the capsule filter A 5 and the capsule filter B 6, namely, valve 35-3 of capsule filter A and valve 36-3 of capsule filter B.

[0053] Valves are installed on the liquid phase pipeline 12 connected in parallel at the bottom of capsule filter A 5 and capsule filter B 6, namely capsule filter A valve 4 5-4 and capsule filter B valve 4 6-4.

[0054] The filter membranes of the capsule filters A5 and B6 are made of PTFE, ceramic, or 316L metal. In the following embodiments of this invention, the filter membranes are made of PTFE.

[0055] A nitrogen valve 16 is installed at the top of reactor 3; a gas phase valve 14 is installed on the pipeline from the top of reactor 3 to the first distillation column 8, and a gas phase feed pump 15 is installed on the pipeline.

[0056] The capsule filter A 5 and capsule filter B 6 are respectively provided with nitrogen inlet pipes at the top, namely nitrogen inlet pipe A-5-1 and nitrogen inlet pipe B-6-1, and respectively are provided with valves on nitrogen inlet pipe A-5-1 and nitrogen inlet pipe B-6-1, namely nitrogen inlet pipe A valve 2 5-2 and nitrogen inlet pipe B valve 2 6-2.

[0057] The capsule filter A 5 and capsule filter B 6 are respectively provided with nitrogen output pipes at the bottom, namely nitrogen output pipe A 6 5-6 and nitrogen output pipe B 6 6-6, and respectively provided with valves on nitrogen output pipe A 6 5-6 and nitrogen output pipe B 6 6-6, namely nitrogen output pipe A valve 5 5-5 and nitrogen output pipe B valve 5 6-5;

[0058] Nitrogen output pipes A-5-1 and B-6-1 merge and are connected to vacuum pipe 13; the bottom of reactor 3 is connected to exhaust pipe 13, and an exhaust pipe vacuum pump 7 is installed on the exhaust pipe.

[0059] The first distillation column 8 is connected to heat exchanger 9, and the second distillation column 10 is connected to heat exchanger 11. The heat exchangers use liquid nitrogen as a refrigerant.

[0060] use Figure 1 The production system shown uses the following production method:

[0061] S1: Open the bottom valve of the reactor, start the vacuum pump 7 in the vent pipe to evacuate the reactor, then close the bottom valve, open the nitrogen valve and the valves of other parts of the device, purge and replace with nitrogen, and then close the valves of all parts.

[0062] S2: Add 138 kg of NaNO2 solid to the reactor, open the water pipe valve, add 150 L of water to the reactor, then close the water pipe valve, open the sulfuric acid feed line valve, and add 98 kg of 60% dilute sulfuric acid to the reactor through the sulfuric acid metering pump to carry out the reaction.

[0063] S3: When the reactor pressure is greater than 1 bar, open the gas phase valve 14 connected to the distillation column, start the liquid phase feed pump 4, open the capsule filter A valve 5-3, capsule filter A valve 5-4 and reactor bottom valve on capsule filter A to form a circulation between the reactor and the capsule reactor. When the pressure difference between the two ends of capsule reactor A 5 reaches 0.6 MPa, first close the capsule filter A valve 5-3, open the capsule filter B valve 6-3 and capsule filter B valve 6-4, and finally close the capsule filter A valve 5-4. Open the nitrogen output pipeline A valve 5-5, start the venting pipe vacuum pump 7 to evacuate capsule filter A 5, so that the Na2SO4 supersaturated crystals precipitated on the filter screen fall to the bottom of the capsule filter and are vented through the venting pipe. Close valve 5-5.

[0064] S4: When the pressure difference across the two ends of the capsule reactor B6 reaches 0.6MPa, first close the capsule filter B valve 3 6-3 and open the capsule filter A valve 3 5-3 and capsule filter A valve 4 5-4 on the capsule filter A5. Finally, close the capsule filter B valve 4 6-4, open the nitrogen output pipe B valve 5 6-5, start the vent pipe vacuum pump 7, and evacuate the capsule filter B6 to make the Na2SO4 supersaturated crystals precipitated on the filter screen fall to the bottom of the capsule filter. Vent the Na2SO4 supersaturated crystals through the vent pipe, close the nitrogen output pipe B valve 5 6-5, and repeat the S3 operation to switch to capsule filter A.

[0065] S5: Nitric oxide gas produced by the reactor enters the first and second distillation columns. Electronic-grade nitric oxide is collected from the second distillation column and filled into steel cylinders.

[0066] S6: After nitric oxide is no longer generated in the reactor, switch to the standby reactor to start the S2-S5 reaction process, open the bottom valve of the reactor, start the vacuum pump 7 of the vent pipe, and discharge the reactants in the reactor to the waste liquid tank through the vent pipe.

[0067] In step S6, the first distillation column has 28 trays, with the feed tray being the 20th tray from the bottom; the second distillation column has 32 trays, with the feed tray being the 20th tray from the bottom; the top temperature of the first distillation column is -109 to -107°C, the bottom temperature is -106 to -104°C, and the reflux ratio of the first distillation column is 3; the top temperature of the second distillation column is -136 to -134°C, the bottom temperature is -108 to -106°C, and the reflux ratio of the first distillation column is 25.

[0068] The electronic-grade nitric oxide in Example 1 has a purity of 99.995%.

[0069] The above embodiments are merely preferred technical solutions of this utility model and should not be considered as limitations on this utility model. The embodiments and features described in this application can be arbitrarily combined without conflict. The protection scope of this utility model should be defined as the technical solution described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the protection scope of this utility model.

Claims

1. A production apparatus for electronic-grade nitric oxide, characterized in that: The production apparatus includes a sulfuric acid storage tank (1), a reactor (3), a capsule filter A (5), and a capsule filter B (6). The top of the capsule filter A (5) and the capsule filter B (6) are connected in parallel through a pipe, and the bottom of the capsule filter A (5) and the capsule filter B (6) are connected in parallel through a pipe, so that the capsule filter A (5) and the capsule filter B (6) can be switched between each other. The bottom outlet of the reactor (3) is connected to the top of the capsule filter A (5) and capsule filter B (6) via a liquid phase feed pump (4) to form a circulation pipeline; The liquid phase pipeline 1 (12) connected in parallel at the bottom of the capsule filter A (5) and capsule filter B (6) is then connected to the lower inlet of the reactor (3) to form a circulation pipeline; The upper outlet pipe of the reactor (3) is connected to the first distillation column (8) and the second distillation column (10), and electronic-grade nitric oxide is collected from the second distillation column (10) and filled into a steel cylinder.

2. The apparatus for producing electronic-grade nitric oxide according to claim 1, characterized in that: The reactor (3) is equipped with a sulfuric acid storage tank (1) and a water inlet pipe (2) at the top. Valves are installed on the pipes that are connected in parallel at the top of the capsule filter A (5) and capsule filter B (6), namely, valve three (5-3) of capsule filter A and valve three (6-3) of capsule filter B.

3. The apparatus for producing electronic-grade nitric oxide according to claim 1, characterized in that: Valves are installed on the liquid phase pipeline 1 (12) that is connected in parallel at the bottom of the capsule filter A (5) and capsule filter B (6), namely, valve 4 (5-4) of capsule filter A and valve 4 (6-4) of capsule filter B.

4. The apparatus for producing electronic-grade nitric oxide according to claim 1, characterized in that: A nitrogen valve (16) is installed at the top of the reactor (3); a gas phase valve (14) is installed on the pipeline from the top of the reactor (3) to the first distillation column (8), and a gas phase feed pump (15) is installed on the pipeline.

5. The apparatus for producing electronic-grade nitric oxide according to claim 4, characterized in that: The capsule filter A (5) and capsule filter B (6) are respectively provided with nitrogen inlet pipes at the top, namely nitrogen inlet pipe A- (5-1) and nitrogen inlet pipe B- (6-1), and respectively provided with valves on nitrogen inlet pipe A- (5-1) and nitrogen inlet pipe B- (6-1), namely nitrogen inlet pipe A valve 2 (5-2) and nitrogen inlet pipe B valve 2 (6-2).

6. The apparatus for producing electronic-grade nitric oxide according to claim 5, characterized in that: The capsule filter A (5) and capsule filter B (6) are respectively provided with nitrogen output pipes at the bottom, namely nitrogen output pipe A (5-6) and nitrogen output pipe B (6-6), and respectively provided with valves, namely nitrogen output pipe A valve (5-5) and nitrogen output pipe B valve (6-5).

7. The apparatus for producing electronic-grade nitric oxide according to claim 6, characterized in that: Nitrogen output pipe A-(5-1) and nitrogen output pipe B-(6-1) are connected to the vent pipe (13) after they merge; the bottom of the reactor (3) is connected to the vent pipe (13), and a vent pipe vacuum pump (7) is installed on the vent pipe.

8. The apparatus for producing electronic-grade nitric oxide according to claim 1, characterized in that: The first distillation column (8) is connected to heat exchanger one (9), and the second distillation column (10) is connected to heat exchanger two (11). The heat exchangers use liquid nitrogen as a refrigerant.

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