Application of supported catalyst in groundwater repairing of groundwater circulating well

Abstract

The invention belongs to the technical field of environmental governance, and particularly relates to application of a supported catalyst in groundwater remediation of a groundwater circulation well. The invention provides an application of a supported catalyst in groundwater restoration of a groundwater circulation well. The supported catalyst comprises activated carbon fibers and copper oxide supported in the activated carbon fibers. When the supported catalyst is used for treating underground water in an underground water circulating well, copper oxide serving as a catalyst can activate oxygen serving as an oxidizing agent under the aeration effect, and active species such as Cu < 3 + > and O2 <.-> are generated through lattice Cu < + > in-situ activation; then degrading the organic pollutants through oxidation-reduction reaction to promote the organic pollutants to generate small molecular organic matters or carbon dioxide and water; meanwhile, under the action of the activated carbon fibers, part of organic pollutants in the underground water and small molecular organic matters generated by degradation are adsorbed among pores of the activated carbon fibers, so that the purpose of efficiently removing semi-volatile organic pollutants and non-volatile organic pollutants in the underground water is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental governance, and specifically relates to the application of a supported catalyst in repairing groundwater in a groundwater circulation well. Background Art

[0002] With the development of industry and cities, groundwater has been increasingly polluted. Typical organic pollutants found in groundwater include petroleum hydrocarbons, benzene series and polycyclic aromatic hydrocarbons, and complex pollution types are common. Organic pollution in groundwater poses a serious threat to the ecological environment and human health. Therefore, it is necessary to treat contaminated groundwater through localized and highly applicable remediation technologies and methods to effectively control the harm of contaminated sites to human health and the ecological environment. The existing remediation methods mainly include extraction treatment, gas injection-soil gas extraction, intrinsic biological purification, in-situ reaction wall method and groundwater circulation well (GCW) method, among which groundwater circulation well is a widely used method for groundwater remediation.

[0003] As an in-situ remediation technology, groundwater circulation well has active remediation. This technology combines stripping, air injection, gas extraction and enhanced bioremediation and other technologies in the well, which can promote the dissolution and migration of pollutants. Through aeration in the well, the groundwater forms a cycle, carrying volatile and semi-volatile organic pollutants dissolved in the groundwater into the inner well. Through aeration stripping, the remediation efficiency can be improved and the remediation cost can be reduced. It has shown great application prospects in the actual site remediation process. However, GCW technology has some unavoidable defects, which limit its further application, such as (1) the scope of application is narrow. At present, site pollution is mostly complex pollution. The degradation rate of semi-volatile organic pollutants and difficult volatile organic pollutants by GCW technology is low; (2) Enhanced microbial technology can assist in the degradation of semi-volatile organic pollutants and difficult volatile organic pollutants, but microbial technology has poor stability, many influencing factors, and slow degradation rate of pollutants; (3) Chemical oxidation method with external agent can achieve the purpose of rapid degradation of semi-volatile organic pollutants and difficult volatile organic pollutants, but it may cause secondary pollution.

[0004] How to enhance the degradation efficiency of semi-volatile organic pollutants and non-volatile organic pollutants in the groundwater circulation process in the long term is a technical problem that needs to be solved urgently. Summary of the invention

[0005] In view of this, the present invention provides an application of a supported catalyst in groundwater circulation wells for repairing groundwater. After adding the supported catalyst to the groundwater circulation well, the present invention can efficiently degrade semi-volatile organic pollutants and non-volatile organic pollutants in the groundwater without adding an external oxidant, thereby expanding the scope of application of the groundwater circulation well.

[0006] In order to solve the above technical problems, the present invention provides an application of a supported catalyst in remediating groundwater in a groundwater circulation well. The supported catalyst comprises activated carbon fibers and copper oxide supported on the activated carbon fibers.

[0007] Preferably, the application method is to place the supported catalyst at the water outlet of the upper flower hole of the groundwater circulation well to degrade organic pollutants in the groundwater under the action of aeration.

[0008] Preferably, the organic pollutant comprises 2-mercaptobenzothiazole;

[0009] The aeration gas includes air or oxygen, and the aeration volume of the aeration is 300-500 L / h; the aeration gas is used as an oxidant for degradation.

[0010] Preferably, the activated carbon fiber includes polyacrylonitrile-based carbon fiber, asphalt-based carbon fiber or viscose-based carbon fiber, and the activated carbon fiber includes activated carbon fiber cloth or activated carbon fiber felt;

[0011] The mass ratio of copper oxide to activated carbon fiber in the supported catalyst is 23.28-70.15:1000.

[0012] Preferably, the method for preparing the supported catalyst comprises the following steps:

[0013] The activated carbon fiber is immersed in a copper salt solution to obtain an immersed material;

[0014] The soaked material is calcined to obtain the supported catalyst.

[0015] Preferably, the copper salt in the copper salt solution includes copper nitrate;

[0016] The mass concentration of the copper salt solution is 2-5%.

[0017] Preferably, the soaking time is 22 to 26 hours.

[0018] Preferably, after the soaking, the method further comprises: draining the soaked material and drying it to obtain a soaked material;

[0019] The drying temperature is 80-100° C. and the drying time is 10-20 hours.

[0020] Preferably, the calcination is carried out under a protective atmosphere;

[0021] The calcination temperature is 250-500° C. and the calcination time is 1.5-2.5 hours.

[0022] Preferably, after the calcination, the step further comprises: cooling the calcined product, washing it with water and drying it in sequence to obtain the supported catalyst;

[0023] The temperature after cooling is 30-70°C;

[0024] The number of times of water washing is 5 to 8 times.

[0025] The present invention provides an application of a supported catalyst in groundwater circulation well repairing groundwater, wherein the supported catalyst comprises activated carbon fiber and copper oxide supported in the activated carbon fiber. When the supported catalyst is used in groundwater circulation well to treat groundwater, copper oxide as a catalyst can activate oxygen in aeration gas as an oxidant under aeration, and the copper oxide can be used as an oxidant through the lattice Cu + In situ activation produces Cu 3+ 、O2· - Then, the organic pollutants (such as 2-mercaptobenzothiazole) are degraded through redox reactions to promote the generation of small molecular organic matter or carbon dioxide and water. At the same time, under the action of activated carbon fibers, some organic pollutants in the groundwater and the small molecular organic matter generated by degradation are adsorbed in the pores of the activated carbon fibers, achieving the purpose of efficiently removing semi-volatile organic pollutants and non-volatile organic pollutants in groundwater. DETAILED DESCRIPTION

[0026] The invention provides an application of a supported catalyst in repairing groundwater in a groundwater circulation well. The supported catalyst comprises activated carbon fiber and copper oxide supported on the activated carbon fiber.

[0027] As a specific embodiment of the present invention, the activated carbon fiber may include polyacrylonitrile-based carbon fiber, asphalt-based carbon fiber or viscose-based carbon fiber, and the activated carbon fiber may include activated carbon fiber cloth or activated carbon fiber felt; the mass ratio of copper oxide to activated carbon fiber in the supported catalyst is 23.28-70.15:1000, and may be specifically 23.28:1000, 23.76:1000, 25.21:1000, 25.94:1000, 29.29:1000, 32.27:1000, 52.17:1000, 53.4:1000, 57.17:1000, 59.12:1000, 60.20:1000, 70.15:1000. In the present invention, the activated carbon fiber has a large specific surface area and can load more copper oxide without affecting the passage of water. When the supported catalyst is directly applied to the groundwater circulation well, no external agent is needed, and the groundwater has a large contact area with the supported catalyst, thus having a good degradation effect on organic pollutants in the groundwater.

[0028] As a specific embodiment of the present invention, the method for preparing the supported catalyst may include the following steps:

[0029] The activated carbon fiber is immersed in a copper salt solution to obtain an immersed material;

[0030] The soaked material is calcined to obtain the supported catalyst.

[0031] The present invention soaks activated carbon fiber in a copper salt solution to obtain an soaked product. As a specific embodiment of the present invention, the copper salt in the copper salt solution may include copper nitrate; the mass concentration of the copper salt solution may be 2-5%, specifically 3% or 4%. As a specific embodiment of the present invention, the copper salt is dissolved in water to obtain a copper salt solution; the present invention has no special requirements for the dissolution, as long as it can be completely dissolved.

[0032] As a specific embodiment of the present invention, the activated carbon fiber can be specifically polyacrylonitrile-based carbon fiber, asphalt-based carbon fiber or viscose-based carbon fiber, and the activated carbon fiber includes activated carbon fiber cloth or activated carbon fiber felt; when the activated carbon fiber is immersed in a copper salt solution, the volume ratio of the activated carbon fiber to the copper nitrate solution can be 5.0g:90~110mL, and can be specifically 5.0g:100mL.

[0033] As a specific embodiment of the present invention, the soaking time may be 22 to 26 hours, and may be specifically 23 hours, 24 hours or 25 hours; the soaking temperature may be room temperature, and the room temperature may be 20 to 30°C.

[0034] As a specific embodiment of the present invention, the soaking may further include: draining the soaked material and then drying it to obtain a soaked material; the drying temperature may be 80 to 100°C, specifically 85°C, 90°C or 95°C; the drying time may be 10 to 20h, specifically 12h, 15h, 18h or 20h.

[0035] After obtaining the soaked material, the present invention calcines the soaked material to obtain the supported catalyst. As a specific embodiment of the present invention, the calcination can be carried out under a protective atmosphere; the protective atmosphere can be specifically argon or nitrogen; the calcination temperature can be 250-500°C, specifically 300°C, 350°C, 400°C or 450°C; the calcination time can be 1.5-2.5h, specifically 2h; the calcination can be carried out in a tubular furnace. The present invention decomposes the copper salt into copper oxide after calcination and loads it in the activated carbon fiber matrix.

[0036] As a specific embodiment of the present invention, the calcination may further include: cooling the calcined product and then washing and drying in sequence to obtain the supported catalyst; the cooling temperature may be 30-70°C, or 30-40°C; the water used for washing may be pure water, and the number of washings may be 5-8 times, or specifically 6 or 7 times; the drying may be drying, and the drying temperature may be 80-100°C, or specifically 85°C, 90°C or 95°C; the present invention has no special requirements for the drying time, as long as the residual water on the surface of the product can be removed. The present invention can wash away the excess copper oxide on the surface of the product through water washing.

[0037] The present invention directly immerses the activated carbon fiber in a copper salt solution, and by adjusting the concentration of the copper salt solution and the calcination temperature, the copper salt is completely decomposed into copper oxide, and is firmly loaded on the activated carbon fiber substrate. The preparation method provided by the present invention is simple and convenient to operate and is easy to industrialize.

[0038] As a specific embodiment of the present invention, the method of using a supported catalyst in a groundwater circulation well to repair groundwater can be to place the supported catalyst at the water outlet of the upper flower hole of the groundwater circulation well, and degrade organic pollutants in the groundwater under aeration; the organic pollutants can include 2-mercaptobenzothiazole; the amount of the supported catalyst added in the groundwater circulation well can be set according to the concentration of organic pollutants in the groundwater, specifically, when the concentration of organic pollutants in the groundwater is 200ppm, 100mL of groundwater requires 0.03-0.20g of supported catalyst, which can be specifically 0.03g, 0.06g, 0.1g, 0.15g or 0.2g. As a specific embodiment of the present invention, the aeration volume of the aeration can be 300-500L / h, which can be specifically 300L / h, 350L / h, 400L / h, 450L / h or 500L / h; the aeration gas can include air or oxygen, and the aeration gas can be directly used as a degradation oxidant to degrade organic pollutants. The invention can roll the supported catalyst into a cylindrical shape and place it at the water outlet of the upper flower hole of the groundwater circulation well.

[0039] The present invention directly sets the supported catalyst at the water outlet of the upper flower hole of the groundwater circulation well to repair the groundwater without modifying the existing groundwater circulation well, and the operation is simple and convenient; the polluted groundwater will react when flowing through the supported catalyst under the action of aeration, thereby ensuring the contact area between the supported catalyst and the polluted groundwater, and can degrade the organic pollutants in the groundwater to generate some small molecular organic matter, carbon dioxide and water, and the small molecular organic matter generated by degradation will be adsorbed on the activated carbon fiber substrate, thereby reducing the secondary pollution problem of groundwater. The present invention only needs to regularly replace the filler (supported catalyst) to ensure the degradation efficiency of semi-volatile organic pollutants or non-volatile organic pollutants, and will not cause secondary pollution to the environment, and solves the problem of difficulty in removing and operating semi-volatile organic pollutants and non-volatile organic pollutants in groundwater.

[0040] After the present invention uses a supported catalyst to treat groundwater for a period of time, when it is found that the degradation efficiency is weak, it may be that the activated carbon fiber has reached saturation in adsorbing organic pollution or the catalytic activity of the copper oxide loaded on the activated carbon fiber has decreased, or the copper oxide is covered by debris, resulting in a reduced degradation effect. At this time, the supported catalyst can be taken out and directly replaced. The present invention can calcine the taken out supported catalyst at high temperature and then soak it in an acidic solution to remove the adsorbed organic pollutants and the inactivated copper oxide catalyst, and then soak it in a copper salt solution again to load the copper oxide, so that the supported catalyst can be regenerated and recycled. The present invention reduces the specific surface area of ​​the activated carbon fiber substrate to a certain extent by regeneration, but the groundwater can still react.

[0041] The present invention utilizes the aeration effect of GCW technology itself. In addition to enabling groundwater to form a circulation, oxygen can also be used as an oxidant to be activated by copper oxide to produce Cu 3+ 、O2· -Active species such as copper oxide. Therefore, relying on the active species generated by the activated oxidant and the adsorption effect of the activated carbon fiber material, the content of 2-mercaptobenzothiazole (promoter M) in groundwater can be reduced in situ quickly and efficiently. When removing organic pollutants from groundwater by promoting M, the present invention directly rolls the copper oxide-modified activated carbon fiber material into a cylindrical shape and places it at the water outlet of the upper flower hole of the groundwater circulation well. Under the aeration effect of the GCW technology, the groundwater circulates through the copper oxide-modified activated carbon fiber material, thereby removing organic pollutants in the groundwater. The method provided by the present invention overcomes the problems of narrow adaptability and low removal efficiency of traditional GCW technology. It only needs to replace the material regularly, and the removal effect is more significant. No external oxidant is required, the harm to the environment is small, the dosage is small, the cost is low, it is easy to recycle, and it is practical and highly operable. The present invention sets the supported catalyst in the groundwater circulation well, so that the copper ions will not be dispersed in the water due to the water flow, lose the activation effect and cause secondary water pollution. In addition, copper oxide is loaded on the activated carbon fiber material, which accelerates the degradation of pollutants and can be used for a longer time. Moreover, copper oxide can be loaded multiple times, ensuring a high utilization rate of the modified activated carbon fiber material.

[0042] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0043] Example 1

[0044] Dissolve 5.0 g of copper nitrate in 100 mL of distilled water and stir until completely dissolved to obtain a copper nitrate aqueous solution with a mass concentration of 5%;

[0045] 5.0 g of viscose-based carbon fiber cloth was soaked in 100 mL of copper nitrate solution for 24 h. After draining the residual solution, it was placed in an oven at 80 ° C for 15 h. It was placed in a tubular furnace and calcined at 250 ° C for 2 h under argon protection. After cooling to 30 ° C, it was taken out, washed with pure water 5 times, and dried at 80 ° C to obtain a supported catalyst.

[0046] 2-Mercaptobenzothiazole (accelerator M) was used as an organic pollutant to simulate contaminated groundwater for groundwater remediation:

[0047] A solution (pH 8.5) with a promoter M content of 200 ppm was prepared as simulated contaminated groundwater. 0.1 g of the supported catalyst was placed in 100 mL of simulated contaminated groundwater. Under the action of aeration (aeration rate of 400 L / h), adsorption and catalytic degradation tests were carried out. The content of promoter M in the simulated contaminated groundwater was tested at 15 min, 30 min, 1 h, 2 h and 3 h of treatment, and its degradation rate was calculated. The results are listed in Table 4.

[0048] Example 2

[0049] Dissolve 2.0 g of copper nitrate in 100 mL of distilled water and stir until completely dissolved to obtain a copper nitrate aqueous solution with a mass concentration of 2%;

[0050] 5.0 g of viscose-based carbon fiber felt was soaked in 100 mL of copper nitrate solution for 24 h. After draining the residual solution, it was placed in an oven at 100 °C for 12 h. It was placed in a tubular furnace and calcined at 500 °C for 2 h under argon protection. After cooling to 40 °C, it was taken out, washed with pure water 6 times, and dried at 100 °C to obtain a supported catalyst.

[0051] 2-Mercaptobenzothiazole (accelerator M) was used as an organic pollutant to simulate contaminated groundwater for groundwater remediation:

[0052] A solution (pH 8.5) with a promoter M content of 200 ppm was prepared as simulated contaminated groundwater. 0.1 g of the supported catalyst was placed in 100 mL of simulated contaminated groundwater. Under the action of aeration (aeration rate of 400 L / h), adsorption and catalytic degradation tests were carried out. The content of promoter M in the simulated contaminated groundwater was tested at 15 min, 30 min, 1 h, 2 h and 3 h of treatment, and its degradation rate was calculated. The results are listed in Table 4.

[0053] Embodiments 3 to 7

[0054] The supported catalyst was prepared according to the method in Example 1, except that the calcination temperature was the temperature in Table 1;

[0055] The groundwater remediation was carried out according to the method in Example 1.

[0056] Table 1 Calcination temperature during the preparation of Examples 1, 3 to 7 and the copper oxide loading in the prepared products

[0057]

[0058] Embodiments 8 to 12

[0059] The supported catalyst was prepared according to the method in Example 2, except that the calcination temperature was the temperature in Table 2;

[0060] The groundwater remediation was carried out according to the method in Example 2.

[0061] Table 2 Calcination temperature during the preparation of Examples 2, 8 to 12 and the amount of copper oxide loaded in the prepared products

[0062]

[0063] Embodiments 13 to 16

[0064] Prepare the supported catalyst according to the method in Example 2;

[0065] The groundwater remediation was carried out according to the method in Example 2, except that the amount of supported catalyst added to 100 mL of simulated contaminated groundwater was according to the amount in Table 3.

[0066] Table 3 Amount of supported catalyst added during groundwater remediation in Examples 2, 13 to 16

[0067]

[0068] Comparative Example 1

[0069] The supported catalyst was prepared according to the method in Example 2, except that the calcination step was omitted after the viscose-based carbon fiber was soaked in copper nitrate solution, drained and dried;

[0070] The groundwater remediation was carried out according to the method in Example 2.

[0071] Comparative Example 2

[0072] The viscose-based carbon fiber in Example 2 is directly used as a catalyst, and groundwater remediation is performed according to the method in Example 2.

[0073] Comparative Example 3

[0074] Prepare the supported catalyst according to the method in Example 2;

[0075] The groundwater remediation was carried out according to the method in Example 2, except that no aeration was performed during the groundwater remediation process.

[0076] Table 4 Degradation rate of accelerator M in sewage at different treatment times of Examples 1 to 16 and Comparative Examples 1 to 3

[0077]

[0078] It can be seen from Table 4 that the supported catalyst prepared by the present invention can be used in the groundwater circulation well to treat sewage to effectively remove the promoter M. After 3 hours of treatment, the removal rate of the promoter M reaches equilibrium. Referring to the test results of Example 1 and Examples 3 to 7, as well as Examples 2 and Examples 8 to 12, it can be seen that the calcination temperature affects the use effect of the supported catalyst; when the concentration of the copper nitrate impregnation solution is 2%, with the increase of the calcination temperature, the removal rate of the promoter M is higher under the same treatment time, and the balance is reached faster in a shorter time, and the removal effect of the promoter M is optimal at a calcination temperature of 500°C; when the concentration of the copper nitrate impregnation solution is 5%, with the increase of the temperature, the removal of the promoter M first increases and then decreases, and the removal effect of the promoter M is optimal at a calcination temperature of 400°C. In addition, it can be seen that at the same calcination temperature, the increase in the concentration of the copper nitrate solution is not conducive to the removal of the promoter M. When the copper nitrate concentration is 2%, the removal speed of the promoter M is the fastest and the effect is the best.

[0079] With reference to the test results of Example 2 and Examples 13 to 16, it can be seen that as the dosage of the supported catalyst increases, the removal rate of the promoter M in the water increases, and the dosage of the promoter M product increases from 0.03 g / L to 0.2 g / L, and the promoter M removal rate increases from 62.23% to 97.90% after 3 hours of treatment, and the time to reach reaction equilibrium is getting shorter and shorter, and the effect of rapid removal of the promoter M is achieved in 1 hour.

[0080] Referring to the test results of Example 2, Comparative Example 2 and Comparative Example 3, it can be seen that when activated carbon fiber is used alone, the reaction quickly reaches equilibrium, but the removal rate of promoter M after 3 hours of reaction is only 90.70%, which is lower than the removal rate of 97.34% in Example 2. Without air, the supported catalyst is added to the water body, and the removal rate of promoter M after 3 hours of reaction is only 44.65%, which shows that promoter M cannot be removed by copper oxide and activated carbon fiber alone. After air is introduced, oxygen as a nutrient is activated by copper oxide to produce active species, which can degrade promoter M more quickly.

[0081] In Table 1, the degradation rate of promoter M in Example 1 at different treatment times is lower than that of Examples 3 to 7. The reason is that the excessively high concentration of copper nitrate occupies more adsorption sites in the catalyst. The results of Examples 3 to 7 show that with the increase of calcination temperature, copper nitrate can be more thoroughly converted into copper oxide, which increases the content of copper oxide in the catalyst and thus increases the degradation rate of promoter M.

[0082] The catalysts prepared by comparative example 1 (uncalcined), example 9 (calcination temperature of 300°C), example 11 (calcination temperature of 400°C) and example 2 (calcination temperature of 500°C) were used for groundwater remediation according to the method of example 2. After treatment for 1h, 2h, 4h, 6h, 8h and 96h, the copper ion dissolution content on the activated carbon fiber in the simulated sewage was detected. The results are listed in Table 5.

[0083] Table 5 Dissolution amount of copper element in the catalysts prepared in Comparative Example 1, Examples 9, 11 and 2

[0084]

[0085]

[0086] Referring to the test results of Example 2 and Comparative Example 1 in Table 4 and the test results in Table 5, it can be seen that Comparative Example 1 does not undergo high-temperature calcination, the reaction takes a long time to reach equilibrium, and the removal rate of the promoter M only reaches 60.36% after 3 hours of reaction. At the same time, the test results for the copper ion content in the treated water body show that its dissolution concentration exceeds the surface water Class II standard of 1.0 mg / L, causing secondary pollution of the water body, which shows that the copper nitrate solution is only adsorbed by the activated carbon fiber and easily falls off into the water body, and cannot increase the removal of the promoter M, and even occupies the adsorption and reaction sites, reducing the removal rate of the promoter M. The catalyst is prepared by high-temperature calcination in the embodiment. Under the action of air, the removal rate of the promoter M in the water body rises to 97.34%, and the copper ion detection concentration in the water body is far lower than 1.0 mg / L, and there is no precipitation, which shows that the copper nitrate is converted into copper oxide and will not cause secondary pollution to the environment.

[0087] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. An application of a supported catalyst in groundwater remediation in groundwater circulation wells, characterized in that: The supported catalyst comprises activated carbon fiber and copper oxide supported in the activated carbon fiber.

2. The application according to claim 1, characterized in that: The application method is to place the supported catalyst at the water outlet of the upper flower hole of the groundwater circulation well, and degrade the organic pollutants in the groundwater under the action of aeration.

3. The application according to claim 2, characterized in that: The supported catalyst is rolled into a cylindrical shape and placed at the water outlet of the upper flower hole of the groundwater circulation well; The organic pollutants include 2-mercaptobenzothiazole; The aeration gas includes air or oxygen, and the aeration volume of the aeration is 300-500 L / h; the aeration gas is used as an oxidant for degradation.

4. The use according to claim 1, characterized in that: The activated carbon fiber includes polyacrylonitrile-based carbon fiber, asphalt-based carbon fiber or viscose-based carbon fiber, and the activated carbon fiber includes activated carbon fiber cloth or activated carbon fiber felt; The mass ratio of copper oxide to activated carbon fiber in the supported catalyst is 23.28-70.15:1000.

5. The use according to claim 1 or 4, characterized in that: The preparation method of the supported catalyst comprises the following steps: The activated carbon fiber is immersed in a copper salt solution to obtain an immersed material; The soaked material is calcined to obtain the supported catalyst.

6. The use according to claim 5, characterized in that: The copper salt in the copper salt solution includes copper nitrate; The mass concentration of the copper salt solution is 2-5%.

7. The use according to claim 6, characterized in that: The soaking time is 22 to 26 hours.

8. The use according to claim 7, characterized in that: After the soaking, the step further includes: draining the soaked material and drying it to obtain a soaked material; The drying temperature is 80-100° C. and the drying time is 10-20 hours.

9. The use according to claim 5, characterized in that: The calcination is carried out under a protective atmosphere; The calcination temperature is 250-500° C. and the calcination time is 1.5-2.5 hours.

10. The use according to claim 9, characterized in that: After the calcination, the further step includes: cooling the calcined product, washing it with water and drying it in sequence to obtain the supported catalyst; The temperature after cooling is 30-70°C; The number of times of water washing is 5 to 8 times.

Images