A process for the removal 12 Process for preparing an adsorbent for removing carbonyl iron, carbonyl nickel from co tail gas and adsorption system

Abstract

The present application relates to a kind of removal 12 The application relates to a preparation method of an adsorbent for removing carbonyl iron and carbonyl nickel in CO tail gas and an adsorption system. The carbon nanotube is a multi-walled carbon nanotube, and the packing pore structure of the multi-walled carbon nanotube is much more developed than that of activated carbon. The developed packing pore structure is beneficial to the internal diffusion and adsorption of small molecules, and the multi-walled carbon nanotube has obvious advantages in adsorption kinetics. The adsorption capacity of carbonyl iron and carbonyl nickel can be effectively improved by using the composite material made of the multi-walled carbon nanotube and the activated carbon material.

Description

Technical Field

[0001] This invention relates to the field of chemical purification technology, specifically to a method for removing... 12 Preparation method and adsorption system of adsorbents for carbonyl iron and carbonyl nickel in CO tail gas. Background Technology

[0002] 13 CO gas is used to synthesize various carbon-based gases. 13 Important starting materials for labeled compounds are currently mainly produced by cryogenic distillation. 13 CO, specifically utilized 12 CO and 13 The difference in CO volatility enables 12 CO and 13 CO isotope separation.

[0003] exist 13 The production process of CO will generate a large amount of 12 CO exhaust gas, due to 12 CO is toxic and poses an environmental safety hazard, requiring treatment before release, which increases the risk of pollution. 13 The production cost of CO.

[0004] Currently, we need to address 13 CO isotope separation 12 CO exhaust gas can be recycled to produce high-purity electronic gases, for example, the recycled CO exhaust gas can be recycled to produce high-purity electronic gases. 12 CO exhaust gas is used as an etching gas for semiconductor devices to create good economic benefits, reduce exhaust emissions and environmental pollution, and achieve resource recycling. However, when CO is used as a purging gas for etching semiconductor devices, trace impurities in CO can cause defects in products with high-density integrated circuits. 12 CO exhaust gas reacts with components on the surface of the steel pipes it comes into contact with to form iron carbonyl Fe(CO)5 and nickel carbonyl Ni(CO)4. Therefore, in 12 Before the CO tail gas undergoes low-temperature distillation, impurities such as carbonyl iron and carbonyl nickel need to be removed to prevent them from condensing and clogging the pipeline during low-temperature distillation.

[0005] In existing technologies, the removal of carbonyl iron and carbonyl nickel from gases typically employs catalyst systems, such as Cu-Zn-Cr metal system catalysts. However, these catalysts suffer from high production costs, complex processes, difficulty in disposing of spent catalysts, and the generation of new metal ions. Another approach utilizes physical adsorption, such as using activated carbon or other adsorbents to adsorb carbonyl iron (Fe(CO)5) and carbonyl nickel (Ni(CO)4) from gases. Summary of the Invention

[0006] Therefore, it is necessary to provide a removal method.12 Preparation method and adsorption system of adsorbents for carbonyl iron and carbonyl nickel in CO tail gas.

[0007] To achieve the above objectives, the present invention provides a technical solution:

[0008] A kind of removal 12 The preparation method of adsorbents containing carbonyl iron and carbonyl nickel in CO tail gas includes the following steps:

[0009] Carbon nanotubes are acidified to obtain acidified carbon nanotubes.

[0010] The acidified carbon nanotubes were added to a dispersant and dispersed to obtain the first mixture.

[0011] A surfactant solution and activated carbon are added to the first mixture to obtain a second mixture;

[0012] The second mixture is subjected to ultrasonication, magnetic stirring, cooling, and filtration. The filtered solid is then washed, dried, ball-milled, and calcined to obtain the removed solid. 12 Adsorbents for carbonyl iron and carbonyl nickel in CO tail gas.

[0013] Preferably, the specific steps for acidifying the carbon nanotubes are as follows:

[0014] Carbon nanotubes are added to an acid solution and refluxed and stirred at 80℃~100℃ for 3h~5h. After the solution cools to room temperature, it is repeatedly washed and filtered with water until the filtrate becomes neutral. The resulting solid is then dried at 60℃~70℃ to obtain acidified multi-walled carbon nanotubes.

[0015] Preferably, the acid solution is a mixture of concentrated sulfuric acid and concentrated nitric acid in a volume ratio of (1-1.2):1.

[0016] Preferably, the mass ratio of the carbon nanotubes to the acid solution is 1:(20-25).

[0017] Preferably, the dispersant comprises at least two of ethanol, methanol, and water.

[0018] Preferably, the volume ratio of ethanol and / or methanol to water is 1:(3-4).

[0019] Preferably, the surfactant is sodium dodecylbenzenesulfonate and sodium dodecyl sulfonate.

[0020] Preferably, the calcination temperature is 200℃~250℃, and the calcination time is 1h~2h.

[0021] Preferably, the mass concentration of the surface active agent is 5% to 8%.

[0022] An adsorption system includes a first diaphragm compressor, a first adsorption tank, a second adsorption tank, a cryogenic distillation section, an intermediate storage tank, a third adsorption tank, and a second diaphragm compressor connected in sequence. The system incorporates the desorption agent described in claim 1 into the first, second, and third adsorption tanks. 12 Adsorbents for carbonyl iron and carbonyl nickel in CO tail gas.

[0023] Preferably, the adsorption system further includes a fourth adsorption tank, a fifth adsorption tank, and a sixth adsorption tank, wherein the fourth adsorption tank is a backup adsorption tank for the first adsorption tank, the fifth adsorption tank is a backup adsorption tank for the second adsorption tank, and the sixth adsorption tank is a backup adsorption tank for the third adsorption tank.

[0024] The beneficial effects of this invention are:

[0025] 1. This invention provides a method for removing... 12 An adsorbent for removing carbonyl iron and carbonyl nickel from CO exhaust gas is prepared by mechanically mixing acidified carbon nanotubes with activated carbon and then ball milling. The carbon nanotubes are multi-walled carbon nanotubes, whose packed pore structure is far more developed than that of activated carbon. This developed packed pore structure facilitates the internal diffusion and adsorption of small molecules, giving multi-walled carbon nanotubes a significant advantage in adsorption kinetics. The composite material made from multi-walled carbon nanotubes and activated carbon can effectively enhance the adsorption capacity for carbonyl iron and carbonyl nickel.

[0026] 2. This invention provides an adsorption system that can effectively improve the removal of carbonyl iron and carbonyl nickel. The device is suitable for the method described in this invention. 12 Carbonyl iron and carbonyl nickel will be effectively removed from CO exhaust gas, and the device achieves this removal through electric heating. 12 Reuse of adsorbents for carbonyl iron and carbonyl nickel in CO tail gas;

[0027] 3. This invention provides an adsorption system for removing carbonyl iron and carbonyl nickel. The system is simple to operate, low in cost, and suitable for industrial production.

[0028] 4. This invention provides an adsorption system for removing carbonyl iron and carbonyl nickel, wherein the product obtained after processing by the system is... 12 The carbonyl iron content in CO is less than 10 ppb, and the carbonyl nickel content is less than 1 ppb. Attached Figure Description

[0029] Figure 1 This is an adsorption system in one embodiment. Detailed Implementation

[0030] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0031] In the embodiments, unless otherwise specified, the experimental methods used are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0032] A kind of removal 12 The preparation method of adsorbents containing carbonyl iron and carbonyl nickel in CO tail gas includes the following steps:

[0033] Carbon nanotubes are acidified to obtain acidified carbon nanotubes.

[0034] The acidified carbon nanotubes were added to a dispersant and dispersed to obtain the first mixture.

[0035] A surfactant solution and activated carbon are added to the first mixture to obtain a second mixture;

[0036] The second mixture is subjected to ultrasonication, magnetic stirring, cooling, and filtration. The filtered solid is then washed, dried, ball-milled, and calcined to obtain the removed solid. 12 Adsorbents for carbonyl iron and carbonyl nickel in CO tail gas.

[0037] Specifically, the carbon nanotubes are multi-walled carbon nanotubes. The stacked pore structure of multi-walled carbon nanotubes is much more developed than that of activated carbon. The developed stacked pore structure is conducive to the internal diffusion and adsorption of small molecules. In terms of adsorption kinetics, multi-walled carbon nanotubes have obvious advantages. By making composite materials from multi-walled carbon nanotubes and activated carbon, the adsorption capacity of carbonyl iron and carbonyl nickel can be effectively improved.

[0038] In one embodiment, the specific steps for acidifying the carbon nanotubes are as follows:

[0039] Carbon nanotubes are added to an acid solution and refluxed and stirred at 80℃~100℃ for 3h~5h. After the solution cools to room temperature, it is repeatedly washed and filtered with water until the filtrate becomes neutral. The resulting solid is then dried at 60℃~70℃ to obtain acidified multi-walled carbon nanotubes.

[0040] In one embodiment, the acid solution is a mixture of concentrated sulfuric acid and concentrated nitric acid in a volume ratio of 1:1 to 1.2:1.

[0041] In one embodiment, the mass ratio of the carbon nanotubes to the acid solution is 1:(20-25).

[0042] In one embodiment, the dispersant comprises at least two of ethanol, methanol, and water.

[0043] In one embodiment, the volume ratio of the ethanol and / or methanol to the water is 1:(3-4).

[0044] In one embodiment, the surfactant is sodium dodecylbenzenesulfonate and sodium dodecyl sulfonate.

[0045] In one embodiment, the calcination temperature is 200℃~250℃, and the calcination time is 1h~2h.

[0046] In one embodiment, the mass concentration of the surfactant is 5% to 8%.

[0047] An adsorption system, such as Figure 1 As shown, the system includes a first diaphragm compressor, a first adsorption tank, a second adsorption tank, a cryogenic distillation section, an intermediate storage tank, a third adsorption tank, and a second diaphragm compressor connected in sequence. The removal process described in claim 1 is added to the first adsorption tank, the second adsorption tank, and the third adsorption tank. 12 Adsorbents for carbonyl iron and carbonyl nickel in CO tail gas.

[0048] In one embodiment, the adsorption system further includes a fourth adsorption tank, a fifth adsorption tank, and a sixth adsorption tank, wherein the fourth adsorption tank is a backup adsorption tank for the first adsorption tank, the fifth adsorption tank is a backup adsorption tank for the second adsorption tank, and the sixth adsorption tank is a backup adsorption tank for the third adsorption tank.

[0049] Specifically, the above-mentioned adsorption system is used to remove 12 The specific processes by which metallic impurities such as carbonyl iron and carbonyl nickel are extracted from CO exhaust gas are as follows:

[0050] Firstly, a first diaphragm compressor is used to... 12 After being pressurized, the CO tail gas enters the first and second adsorption tanks. After a removal process, it enters the cryogenic distillation section, then the intermediate storage tank, and finally the third adsorption tank. After completing the removal process, it is compressed by the second diaphragm compressor and enters the filling outlet to obtain high-purity CO. 12 CO bottled products.

[0051] Example 1

[0052] Carbon nanotubes were added to a mixed acid solution of concentrated sulfuric acid and concentrated nitric acid in a volume ratio of 1:1, with a mass ratio of carbon nanotubes to acid solution of 1:20. The solution was refluxed and stirred at 80°C for 3 hours. After the solution cooled to room temperature, it was repeatedly washed and filtered with water until the filtrate became neutral. The resulting solid was then dried at 60°C to obtain the acidified multi-walled carbon nanotubes.

[0053] The acidified carbon nanotubes were added to ethanol and water dispersant, with the volume ratio of ethanol to water being 1:3, and dispersed to obtain the first mixture.

[0054] A 5% (w / w) sodium dodecylbenzenesulfonate surfactant solution and activated carbon were added to the first mixture to obtain the second mixture.

[0055] The second mixture was subjected to ultrasonication, magnetic stirring, cooling, and filtration. The filtered solid was then washed, dried, ball-milled, and calcined at 200°C for 1 hour. This yielded the removed... 12 Adsorbents for carbonyl iron and carbonyl nickel in CO tail gas.

[0056] Example 2

[0057] Carbon nanotubes were added to a mixed acid solution of concentrated sulfuric acid and concentrated nitric acid at a volume ratio of 1.2:1, with a mass ratio of carbon nanotubes to the acid solution of 1:25. The solution was refluxed and stirred at 100°C for 5 hours. After the solution cooled to room temperature, it was repeatedly washed and filtered with water until the filtrate became neutral. The resulting solid was then dried at 70°C to obtain the acidified multi-walled carbon nanotubes.

[0058] The acidified carbon nanotubes were added to methanol and water dispersant, with a volume ratio of methanol to water of 1:4.

[0059] Dispersion yields the first mixture;

[0060] Add an 8% (w / w) sodium dodecyl sulfonate surfactant solution and activated carbon to the first mixture to obtain the second mixture;

[0061] The second mixture was subjected to ultrasonication, magnetic stirring, cooling, and filtration. The filtered solid was then washed, dried, ball-milled, and calcined at 250°C for 2 hours. This yielded the removed... 12 Adsorbents for carbonyl iron and carbonyl nickel in CO tail gas.

[0062] Example 3

[0063] Carbon nanotubes were added to a mixed acid solution of concentrated sulfuric acid and concentrated nitric acid at a volume ratio of 1.1:1, and the mass ratio of carbon nanotubes to the acid solution was 1:22. The solution was refluxed and stirred at 90°C for 6 hours. After the solution cooled to room temperature, it was repeatedly washed and filtered with water until the filtrate became neutral. The resulting solid was then dried at 65°C to obtain the acidified multi-walled carbon nanotubes.

[0064] The acidified carbon nanotubes were added to methanol and water dispersant, with a volume ratio of methanol to water of 1:3.

[0065] Dispersion yields the first mixture;

[0066] A 6% (w / w) sodium dodecyl sulfonate surfactant solution and activated carbon were added to the first mixture to obtain a second mixture.

[0067] The second mixture was subjected to ultrasonication, magnetic stirring, cooling, and filtration. The filtered solid was then washed, dried, ball-milled, and calcined at 220°C for 1.5 hours. This yielded the removed... 12 Adsorbents for carbonyl iron and carbonyl nickel in CO tail gas.

[0068] Comparative Example 1

[0069] Activated carbon adsorbent.

[0070] Comparative Example 2

[0071] Carbon nanotube adsorbent.

[0072] The adsorbents of Examples 1-3 and Comparative Examples 1-2 were used as follows: Figure 1 The adsorption performance of the shown adsorption system was tested.

[0073] The adsorption system includes a first diaphragm compressor, a first adsorption tank, a second adsorption tank, a cryogenic distillation section, an intermediate storage tank, a third adsorption tank, and a second diaphragm compressor connected in sequence. The adsorbent to be tested is added to the first adsorption tank, the second adsorption tank, and the third adsorption tank.

[0074] The specific tests are as follows:

[0075] Using the first diaphragm compressor to 12 After being pressurized, the CO tail gas enters the first and second adsorption tanks. After a removal process, it enters the cryogenic distillation section, then the intermediate storage tank, and finally the third adsorption tank. After completing the removal process, it is compressed by the second diaphragm compressor and enters the filling outlet to obtain high-purity CO. 12 CO bottled products.

[0076] After adsorption saturation, the adsorption tank can be heated and purged to remove carbonyl iron and carbonyl nickel. After heating is stopped, the tank is cooled and vacuum-purged for later use.

[0077] At an air speed of 10 m / s 3 At an adsorption pressure of 2 MPa, an inlet carbonyl iron concentration of 1.2 ppm, and a carbonyl nickel concentration of 0.1 ppm, the adsorbents obtained in Examples 1, 2, and 3 were compared and analyzed with the adsorbents in Comparative Examples 1 and 2. The results are shown in Table 1.

[0078] Table 1 Adsorption performance test results

[0079] Adsorbent Iron carbonyl / ppm Nickel carbonyl / ppm Example 1 0.005 0.0002 Example 2 0.004 0.0001 Example 3 0.003 0.0001 Comparative Example 1 0.122 0.014 Comparative Example 2 0.098 0.006

[0080] As shown in Table 1 above, the adsorbents prepared in Examples 1-3 have significantly better adsorption effects on carbon-based iron and carbon-based nickel than activated carbon adsorbent (Comparative Example 1) and carbon nanotube adsorbent (Comparative Example 2).

[0081] It should be noted that the specific parameters or reagents in the above embodiments are specific or preferred embodiments under the concept of the present invention, and not limitations thereof; those skilled in the art can make adaptive adjustments within the concept and protection scope of the present invention.

Claims

1. A process for the removal of 12 CO tail gas of carbonyl iron, carbonyl nickel adsorbent preparation method characterized by, The method comprises the steps of: acidizing carbon nanotubes to obtain acidized carbon nanotubes; adding the acidized carbon nanotubes into a dispersant to obtain a first mixed solution by dispersion; adding a surfactant solution and activated carbon into the first mixed solution to obtain a second mixed solution; The second mixed solution is treated by ultrasonic, magnetic stirring, cooling, filtration, and the filtered solid is washed, dried, ball milled, and calcined to obtain the removal 12 The adsorbent for removing carbonyl iron and carbonyl nickel in CO tail gas, and the CO tail gas treated by the adsorbent has 12 The content of carbonyl iron in the CO tail gas is less than 10 ppb, and the content of carbonyl nickel is less than 1 ppb. the dispersant comprises at least two of ethanol, methanol and water; the surfactant is sodium dodecyl benzene sulfonate and sodium dodecyl sulfonate; the calcination temperature is 200-250℃.

2. The removal of claim 1 12 A method for producing an adsorbent for removing carbonyl iron and carbonyl nickel in a CO tail gas, characterized by, The specific steps of acidizing the carbon nanotubes are as follows: adding the carbon nanotubes into an acid solution and refluxing and stirring at 80-100℃ for 3-5h, after the solution is cooled to room temperature, repeatedly washing and filtering with water until the filtrate is neutral, and then drying the obtained solid at 60-70℃ to obtain the acidized multi-walled carbon nanotubes.

3. The removal of claim 2 12 A method for producing an adsorbent for removing carbonyl iron and carbonyl nickel in a CO tail gas, characterized by, The acid solution is a mixed solution of concentrated sulfuric acid and concentrated nitric acid with a volume ratio of 1:1.

2.

4. The removal of claim 2 12 A method for preparing an adsorbent for removing carbonyl iron and carbonyl nickel in a CO tail gas, characterized by, The mass ratio of the carbon nanotubes to the acid solution is 1:(20-25).

5. The removal of claim 1 12 A method for producing an adsorbent for removing carbonyl iron and carbonyl nickel in a CO tail gas, characterized by, The volume ratio of the ethanol and / or methanol to the water is 1:(3-4).

6. The removal of claim 1 12 A method for producing an adsorbent for removing carbonyl iron and carbonyl nickel in a CO tail gas, characterized by, The calcination time is 1-2h.

7. The removal of claim 1 12 A method for producing an adsorbent for removing carbonyl iron and carbonyl nickel in a CO tail gas, characterized by, The mass concentration of the surfactant is 5-8%.

8. An adsorption system, characterized by The process comprises sequentially connecting a first diaphragm compressor, a first adsorption tank, a second adsorption tank, a low-temperature rectification section, an intermediate storage tank, a third adsorption tank, and a second diaphragm compressor, and adding the prepared adsorbent for removing 12 Adsorbent for removing carbonyl iron and carbonyl nickel in CO tail gas.

9. The adsorption system of claim 8, wherein, The adsorption system further comprises a fourth adsorption tank, a fifth adsorption tank and a sixth adsorption tank, the fourth adsorption tank is a standby adsorption tank of the first adsorption tank, the fifth adsorption tank is a standby adsorption tank of the second adsorption tank, and the sixth adsorption tank is a standby adsorption tank of the third adsorption tank.

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