Preparation process and application of catalyst for treating tail gas containing carbon monoxide

Abstract

The invention relates to the field of carbon-containing exhaust gas treatment, in particular to a preparation process and application of a catalyst for carbon monoxide-containing exhaust gas treatment, and the preparation process of the catalyst comprises the following steps: S1, mixing a CuCl2. 2H2O solution, a NaOH solution and a glucose solution, stirring at room temperature until the mixture becomes brick red, then standing for layering, taking a lower layer precipitate, washing and drying to obtain Cu2O powder; and S2, adding the Cu2O powder and a Ce (NO3) 3.6 H2O solution into deionized water, then adding a NaOH solution, stirring at room temperature until no precipitate is generated, finally standing for layering, taking the precipitate at the lower layer, washing and drying to obtain the CeO2 / Cu2O catalyst. The selected catalyst is low in cost and high in catalytic efficiency, the catalytic efficiency can reach 99%, the preparation process is simple, and large-scale production can be achieved.

Description

Technical Field

[0001] The present application relates to the field of carbon-containing waste gas and tail gas treatment, and specifically to a preparation process and application of a catalyst for treating carbon monoxide-containing tail gas. Background Art

[0002] In the integrated circuit and chip manufacturing process, the purity of carbon monoxide products is subject to extremely strict standards. The tail gas produced in the carbon monoxide distillation process is mainly composed of carbon monoxide with substandard purity. If it is directly discharged without proper treatment, it will not only seriously pollute the natural environment, but also pose a potential threat to human health. For this reason, the country vigorously advocates the innovation and application of carbon monoxide emission treatment technology and strives to achieve carbon neutrality.

[0003] At present, the waste gas treatment of carbon monoxide is mainly carried out through a plasma combustion device, and carbon monoxide is burned to generate carbon dioxide. A method for removing carbon monoxide from flue gas by plasma discharge coupled catalytic oxidation with announcement number CN117205749A is provided. The method is to fill the copper-manganese co-oxide catalyst with oxygen vacancies on the surface into the discharge chamber of the plasma reactor, and then pass the flue gas into the discharge chamber for discharge catalytic oxidation to remove the carbon monoxide component in the flue gas. However, the system equipment of the device is relatively complex, the investment cost is high, and a high technical level and operating experience are required. Secondly, scientists have developed precious metal catalysts to catalyze carbon monoxide. Precious metal catalysts such as gold, platinum, and rhodium all have excellent catalytic effects on carbon monoxide, but in actual production processes, the cost is high and cannot be used in large batches. For example, a Chinese patent with announcement number CN116237042A discloses a catalyst for carbon monoxide oxidation reaction and automobile / blast furnace exhaust purification and a preparation method thereof. The method achieves high dispersion of the silver catalyst under the combined action of an oxygen-rich reaction atmosphere and hydroxyl groups on the surface of the carrier. However, the preparation method is relatively complicated, and its essence is still to use precious metal silver as a catalyst, resulting in a high production cost.

[0004] In summary, it is urgent to propose a preparation process and application of a catalyst for treating carbon monoxide tail gas, so as to solve the problems of high cost and complex process of treating carbon monoxide tail gas in the prior art. Summary of the invention

[0005] In view of the problems of high cost and complicated process of catalysts for treating tail gas containing carbon monoxide in the prior art, the present application proposes a preparation process and application of a catalyst for treating tail gas containing carbon monoxide.

[0006] The technical solution of this application:

[0007] On the one hand, the present application provides a process for preparing a catalyst for treating tail gas containing carbon monoxide, and the catalyst preparation process is as follows:

[0008] Step S1. CuCl2·2H2O solution, NaOH solution and glucose solution are mixed and stirred at room temperature until they turn brick red, and then allowed to stand for stratification, and the lower precipitate is removed, washed and dried to obtain Cu2O powder;

[0009] Step S2. Add Cu2O powder and Ce(NO3)3·6H2O solution to deionized water, then add NaOH solution and stir at room temperature until no more precipitation occurs, finally stand to separate the layers, remove the lower layer of precipitation, wash and dry to obtain CeO2 / Cu2O catalyst.

[0010] Preferably, the mass ratio of the CuCl2·2H2O solution, the NaOH solution and the glucose solution is 1:(1-2):(1-2); the concentration of the CuCl2·2H2O solution is 0.5-3 mol / L, the concentration of the NaOH solution is 0.5-2 mol / L, and the mass fraction of the glucose solution is 5-50%.

[0011] Preferably, the mass ratio of the CuCl2·2H2O solution, the NaOH solution and the glucose solution is 1:(1-1.5):(1-1.5); the concentration of the CuCl2·2H2O solution is 0.5-1 mol / L, the concentration of the NaOH solution is 0.5-1 mol / L, and the mass fraction of the glucose solution is 5-30%.

[0012] Preferably, the order of adding the CuCl2·2H2O solution, the NaOH solution and the glucose solution is to first add the NaOH solution to the CuCl2·2H2O solution and then add the glucose solution.

[0013] Preferably, the stirring time of step S1 is 2 to 5 hours; washing is specifically performed by alternating washing with deionized water and anhydrous ethanol and centrifuging until the pH value of the supernatant is neutral.

[0014] Preferably, in step S2, the purity of Ce(NO3)3·6H2O is 98-99.9%, the concentration of NaOH solution is 0.06-0.6 mol / L; the mass ratio of Cu2O powder, Ce(NO3)3·6H2O solution, NaOH solution and deionized water is 1:(1-1.5):(3-5):(30-50); the stirring time is 2-5h; and the washing is specifically performed by alternating washing with deionized water and anhydrous ethanol and centrifuging until the pH value of the supernatant is neutral.

[0015] Preferably, the drying in step S1 and step S2 is performed by vacuum drying at 60-100° C. for 6-18 hours.

[0016] Preferably, the drying in step S1 and step S2 is performed by vacuum drying at 70-90° C. for 12-15 hours.

[0017] On the other hand, the present application provides an application of a preparation process for a catalyst for treating exhaust gas containing carbon monoxide, characterized in that the exhaust gas containing carbon monoxide is passed through a catalyst to generate carbon dioxide emissions at a temperature of 150°C to 300°C and a pressure of 0.1 to 0.6 MPa, and the flow rate of the carbon monoxide exhaust gas is 3 to 5 kg / h.

[0018] Beneficial effects of this application:

[0019] The catalyst selected in this application is cheap compared to precious metals such as gold, platinum, and rhodium, which reduces the cost of catalysis. On the other hand, both metal copper and cerium belong to transition metals, and have more active sites on the surface, which can adsorb reactants and promote the reaction, which enables them to show good activity in catalytic reactions. The catalyst of this application belongs to a composite oxide. The synergistic effect between copper and cerium can accelerate the transfer of electrons on the surface of the catalyst, help reduce the activation energy of the reaction, increase the rate of the catalytic reaction, and make the catalytic efficiency reach 99%. Using the catalyst prepared in this application, the catalytic temperature can be controlled between 150°C and 300°C. Compared with the high temperature of traditional plasma combustion catalysis of carbon monoxide, the catalytic conditions of this application are milder. Under the conditions of this application, the particle size of the prepared catalyst is within the range of 200 to 500nm, which belongs to the nano category, has the characteristics of a nano catalyst, has a large specific surface area, and more reactive sites are exposed, which accelerates the rate of the catalytic reaction. Due to the large surface area and many active sites, even if some active sites are poisoned, there are still enough active sites for catalytic reaction. The preparation process of this application is simple and can be mass-produced. DETAILED DESCRIPTION

[0020] In order to further explain the technical means and effects adopted by the present application to achieve the predetermined invention purpose, the specific implementation method, structure, characteristics and effects of the present application are described in detail below in combination with the preferred embodiments.

[0021] Catalyst preparation process example

[0022] Example 1

[0023] This embodiment provides a preparation process of a catalyst for treating tail gas containing carbon monoxide, which is specifically as follows:

[0024] Step S1. Take 10g of 0.8mol / L CuCl2·2H2O solution and place it in a beaker, add 15g of 0.8mol / L NaOH solution, then add 15g of 20% glucose solution, stir at room temperature for 3h until it turns brick red, then stand for stratification, centrifuge to remove the upper liquid and take the lower precipitate, wash the precipitate alternately with deionized water and anhydrous ethanol, centrifuge until the pH of the upper clear liquid is neutral, dry it in vacuum at 80℃ for 14h, grind it through a 100-mesh sieve to obtain Cu2O powder.

[0025] Step S2. Add 1g of Cu2O powder and 1.2g of Ce(NO3)3·6H2O solution with a purity of 99.9% to 40g of deionized water, then add 4g of NaOH solution with a concentration of 0.4mol / L, stir at room temperature for 4h until no more precipitation occurs, finally stand for stratification, centrifuge to remove the upper liquid and take the lower precipitate, wash the precipitate alternately with deionized water and anhydrous ethanol, and centrifuge until the pH value of the upper clear liquid is neutral, dry it in vacuum at 80°C for 148h, grind it through a 100-mesh sieve to obtain a CeO2 / Cu2O catalyst with a particle size of 250 to 350mm.

[0026] Example 2

[0027] This embodiment provides a preparation process of a catalyst for treating tail gas containing carbon monoxide, which is specifically as follows:

[0028] Step S1. Take 10g of 0.5mol / L CuCl2·2H2O solution and place it in a beaker, add 20g of 1mol / L NaOH solution, then add 10g of 50% glucose solution, stir at room temperature for 2h until it turns brick red, then stand for stratification, centrifuge to remove the upper liquid and take the lower precipitate, wash the precipitate alternately with deionized water and anhydrous ethanol, centrifuge until the pH of the upper clear liquid is neutral, dry it in vacuum at 100℃ for 6h, grind it through a 100-mesh sieve to obtain Cu2O powder.

[0029] Step S2. Add 1g of Cu2O powder and 1g of Ce(NO3)3·6H2O solution with a purity of 99.9% to 30g of deionized water, then add 5g of NaOH solution with a concentration of 0.2mol / L, stir at room temperature for 5h until no precipitation is produced, finally stand for stratification, centrifuge to remove the upper liquid and take the lower precipitate, wash the precipitate alternately with deionized water and anhydrous ethanol, centrifuge until the pH value of the upper clear liquid is neutral, vacuum dry at 100°C for 6 hours, grind and pass through a 100-mesh sieve to obtain a CeO2 / Cu2O catalyst with a particle size of 200 to 300mm.

[0030] Example 3

[0031] This embodiment provides a preparation process of a catalyst for treating tail gas containing carbon monoxide, which is specifically as follows:

[0032] Step S1. Take 10g of 3mol / L CuCl2·2H2O solution and place it in a beaker, add 10g of 0.5mol / L NaOH solution, then add 20g of 5% glucose solution, stir at room temperature for 5h until it turns brick red, then stand for stratification, centrifuge to remove the upper liquid and take the lower precipitate, wash the precipitate alternately with deionized water and anhydrous ethanol, centrifuge until the pH of the upper clear liquid is neutral, dry it in vacuum at 60℃ for 18h, grind it through a 100-mesh sieve to obtain Cu2O powder.

[0033] Step S2. Add 1g of Cu2O powder and 1.5g of Ce(NO3)3·6H2O solution with a purity of 98% to 50g of deionized water, then add 3g of NaOH solution with a concentration of 0.4mol / L, stir at room temperature for 2h until no precipitation is produced, finally stand for stratification, centrifuge to remove the upper liquid and take the lower precipitate, wash the precipitate alternately with deionized water and anhydrous ethanol, centrifuge until the pH value of the upper clear liquid is neutral, dry it in vacuum at 70°C for 18h, grind it through a 100-mesh sieve to obtain a CeO2 / Cu2O catalyst with a particle size of 300 to 500mm.

[0034] Example 4

[0035] This embodiment provides a preparation process of a catalyst for treating tail gas containing carbon monoxide, which is specifically as follows:

[0036] Step S1. Take 10g of 1.5mol / L CuCl2·2H2O solution and place it in a beaker, add 13g of 1mol / L NaOH solution, then add 13g of 30% glucose solution, stir at room temperature for 3h until it turns brick red, then stand for stratification, centrifuge to remove the upper liquid and take the lower precipitate, wash the precipitate alternately with deionized water and anhydrous ethanol, centrifuge until the pH of the upper clear liquid is neutral, dry it in vacuum at 85℃ for 15h, grind it through a 100-mesh sieve to obtain Cu2O powder.

[0037] Step S2. Add 1g of Cu2O powder and 1.3g of Ce(NO3)3·6H2O solution with a purity of 99.9% to 40g of deionized water, then add 3g of 0.3mol / LNaOH solution, stir at room temperature for 3h until no more precipitation occurs, finally stand for stratification, centrifuge to remove the upper liquid and take the lower precipitate, wash the precipitate alternately with deionized water and anhydrous ethanol, and centrifuge until the pH value of the upper clear liquid is neutral, dry it in vacuum at 85°C for 15h, grind it through a 100-mesh sieve to obtain a CeO2 / Cu2O catalyst with a particle size of 350 to 500mm.

[0038] Application examples of the catalysts prepared in Examples 1 to 4

[0039] Application Example 1

[0040] The tail gas containing carbon monoxide was passed through the catalyst prepared in Example 1, at a temperature of 200°C and a pressure of 0.5 MPa, to generate carbon dioxide for emission, and the flow rate of the tail gas containing carbon monoxide was controlled to be 4 kg / h. The conversion rate of carbon monoxide to carbon dioxide was calculated to be 99%.

[0041] Application Example 2

[0042] The tail gas containing carbon monoxide was passed through the catalyst prepared in Example 2 at a temperature of 150°C and a pressure of 0.4 MPa to generate carbon dioxide for emission, and the flow rate of the tail gas containing carbon monoxide was controlled to be 3.5 kg / h. The conversion rate of carbon monoxide to carbon dioxide was calculated to be 95%.

[0043] Application Example 3

[0044] The tail gas containing carbon monoxide was passed through the catalyst prepared in Example 3, and carbon dioxide was generated and discharged at a temperature of 300°C and a pressure of 0.6 MPa, and the flow rate of the tail gas containing carbon monoxide was controlled to be 5 kg / h. The conversion rate of carbon monoxide to carbon dioxide was calculated to be 85%.

[0045] Application Example 4

[0046] The tail gas containing carbon monoxide was passed through the catalyst prepared in Example 4 at a temperature of 150°C and a pressure of 0.1 MPa to generate carbon dioxide for emission, and the flow rate of the tail gas containing carbon monoxide was controlled to be 3 kg / h. The conversion rate of carbon monoxide to carbon dioxide was calculated to be 89%.

[0047] The above is only a preferred embodiment of the present application and does not constitute any form of limitation to the present application. Although the present application has been disclosed as a preferred embodiment as above, it is not intended to limit the present application. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present application. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A process for preparing a catalyst for treating tail gas containing carbon monoxide, characterized in that: The catalyst preparation process is as follows: Step S1. CuCl2·2H2O solution, NaOH solution and glucose solution are mixed and stirred at room temperature until they turn brick red, and then allowed to stand for stratification, and the lower precipitate is removed, washed and dried to obtain Cu2O powder; Step S2. Add Cu2O powder and Ce(NO3)3·6H2O solution to deionized water, then add NaOH solution and stir at room temperature until no more precipitation occurs, finally stand to separate the layers, remove the lower layer of precipitation, wash and dry to obtain CeO2 / Cu2O catalyst.

2. The process for preparing a catalyst for treating tail gas containing carbon monoxide according to claim 1, characterized in that: The mass ratio of the CuCl2·2H2O solution, the NaOH solution and the glucose solution is 1:(1-2):(1-2); the concentration of the CuCl2·2H2O solution is 0.5-3 mol / L, the concentration of the NaOH solution is 0.5-2 mol / L, and the mass fraction of the glucose solution is 5-50%.

3. The process for preparing a catalyst for treating tail gas containing carbon monoxide according to claim 1, characterized in that: The mass ratio of the CuCl2·2H2O solution, the NaOH solution and the glucose solution is 1:(1-1.5):(1-1.5); the concentration of the CuCl2·2H2O solution is 0.5-1 mol / L, the concentration of the NaOH solution is 0.5-1 mol / L, and the mass fraction of the glucose solution is 5-30%.

4. The process for preparing a catalyst for treating tail gas containing carbon monoxide according to claim 1, characterized in that: The order of adding the CuCl2·2H2O solution, the NaOH solution and the glucose solution is to first add the NaOH solution to the CuCl2·2H2O solution and then add the glucose solution.

5. The process for preparing a catalyst for treating tail gas containing carbon monoxide according to claim 1, characterized in that: The stirring time of step S1 is 2 to 5 hours; the washing is specifically performed by alternating washing with deionized water and anhydrous ethanol and centrifuging until the pH value of the supernatant is neutral.

6. The process for preparing a catalyst for treating tail gas containing carbon monoxide according to claim 1, characterized in that: In step S2, the purity of Ce(NO3)3·6H2O is 98-99.9%, and the concentration of NaOH solution is 0.06-0.6 mol / L; the mass ratio of Cu2O powder, Ce(NO3)3·6H2O solution, NaOH solution and deionized water is 1:(1-1.5):(3-5):(30-50); the stirring time is 2-5 hours; and the washing is specifically performed by alternating washing with deionized water and anhydrous ethanol and centrifuging until the pH value of the supernatant is neutral.

7. The process for preparing a catalyst for treating tail gas containing carbon monoxide according to claim 1, characterized in that: The drying in step S1 and step S2 is performed by vacuum drying at 60-100° C. for 6-18 hours.

8. The process for preparing a catalyst for treating tail gas containing carbon monoxide according to claim 1, characterized in that: The drying in step S1 and step S2 is performed by vacuum drying at 70-90° C. for 12-15 hours.

9. Application of the preparation process of a catalyst for treating tail gas containing carbon monoxide according to any one of claims 1 to 8, characterized in that: The tail gas containing carbon monoxide is passed through a catalyst to generate carbon dioxide emission at a temperature of 150°C to 300°C and a pressure of 0.1 to 0.6 MPa. The flow rate of the carbon monoxide tail gas is 3 to 5 kg / h.