Preparation method of novel cobalt intercalation manganese dioxide catalyst and application of novel cobalt intercalation manganese dioxide catalyst in flue gas demercuration

Abstract

The invention belongs to the technical field of air pollution treatment, and relates to a preparation method of a novel cobalt intercalation manganese dioxide catalyst and application of the novel cobalt intercalation manganese dioxide catalyst in mercury removal of mercury-containing flue gas. The preparation method comprises the following steps: dropwise adding a manganese sulfate solution into a potassium permanganate solution under a stirring condition to obtain a mixed solution; carrying out hydrothermal reaction at the temperature of 140-180 DEG C for 10-15 hours to obtain layered manganese dioxide; and dropwise adding a cobalt salt solution into the layered manganese dioxide solution, stirring, washing and drying the obtained product, keeping the temperature at 300-500 DEG C for 4-6 hours, and calcining to obtain the novel cobalt intercalation manganese dioxide catalyst Co / delta-MnO2. The novel cobalt intercalation manganese dioxide catalyst prepared by the preparation method disclosed by the invention is wide in reaction temperature for catalyzing and removing Hg < 0 >, can remove more than 99% of Hg < 0 > at the temperature of 50-250 DEG C, is strong in adaptive capacity, and still has relatively high catalytic activity in a high sulfur dioxide atmosphere.

Description

Technical Field

[0001] The invention belongs to the technical field of air pollution treatment, and relates to a catalyst for removing elemental mercury in flue gas and waste gas, and specifically to a preparation method of a novel cobalt intercalated manganese dioxide catalyst and its application in flue gas mercury removal. Background Art

[0002] Mercury is the only metal element that is liquid at room temperature. It is highly toxic, persistent and volatile. It can accumulate in organisms and migrate between the environment and organisms, causing serious impacts on human health and the ecological environment. At the same time, mercury pollution has the property of global migration and has been listed as a global pollutant. At present, the elemental mercury (Hg 0 ) Activated carbon is generally used for adsorption removal, but since the removal cost of activated carbon injection technology is too high, many researchers are developing different adsorbents and catalysts to replace activated carbon for mercury removal in flue gas.

[0003] Manganese-based oxides have the advantages of low cost and high natural abundance. They also have abundant oxygen free radicals, strong oxidizing and adsorption capacity, and balanced acid-base properties. They have shown excellent catalytic and adsorption properties in the control of elemental mercury pollution. However, manganese-based oxides also have small specific surface area and are easily affected by sulfur dioxide (SO 2 ) poisoning, etc., so it is urgent to develop new manganese-based materials with high activity, high resistance and high stability.

[0004] MnO 2 Different phase structures can be formed, which can be roughly divided into two categories: one is MnO with tunnel structure 2 , the main crystal form is α-MnO 2 ,β-MnO 2 ,γ-MnO 2 ; One is a crystal form with a two-dimensional layered structure, namely δ-MnO 2 Among them, the layered structure of δ-MnO 2 It has the characteristics of high specific surface area, ion exchange activity and simple preparation, and it is easy to achieve interlayer cation exchange, so it has been widely studied.

[0005] Chinese invention patent CN115212870A discloses a cesium-doped sodium-type layered manganese dioxide catalyst for removing VOCs. Although it also belongs to a layered manganese dioxide material, its preparation method is to add an oxidant (such as hydrogen peroxide), sodium hydroxide and a cesium salt (cesium acetate, cesium sulfate, cesium nitrate or cesium chloride) to a manganese salt (manganese acetate, manganese sulfate, manganese nitrate or manganese chloride), perform a hydrothermal reaction at 120-180°C, and calcine at 250-400°C. In addition, the manganese-based material prepared by the invention is used in the technical field of catalytic oxidation to remove VOCs. Summary of the invention

[0006] The purpose of the present invention is to solve the above-mentioned problems existing in the prior art, and a preparation method of a novel cobalt intercalation manganese dioxide catalyst and its application in flue gas mercury removal are proposed. Potassium permanganate and manganese sulfate are dissolved in distilled water respectively, and a high-temperature hydrothermal reaction is carried out to obtain layered manganese dioxide. The excellent ion exchange performance of the layered manganese dioxide is utilized to allow cobalt metal ions to enter the interlayers of the layered manganese dioxide to carry out ion exchange, so that the prepared novel cobalt intercalation manganese dioxide catalyst has the characteristics of high activity and high sulfur resistance, which is conducive to practical use.

[0007] The technical solution of the present invention is:

[0008] The present invention provides a method for preparing a novel cobalt intercalated manganese dioxide catalyst, comprising the following steps:

[0009] (1) dissolving potassium permanganate and manganese sulfate in a molar ratio of 1:(2.5-7) in distilled water to obtain a potassium permanganate solution and a manganese sulfate solution, and adding the manganese sulfate solution dropwise to the potassium permanganate solution under stirring to obtain a mixed solution;

[0010] The molar ratio of potassium permanganate to manganese sulfate is 1:(2.5-7), for example, it can be 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, 1:5.2, 1:5.4, 1:5.5, 1:5.6, 1:5.7, 1:5.8, 1:5.9, 1:6, 1:6.5 or 1:7, but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0011] (2) The mixed solution is subjected to a hydrothermal reaction at a temperature of 140 to 180° C. for 10 to 15 hours to obtain a solid product, which is repeatedly filtered, washed with water, and dried to obtain layered manganese dioxide δ-MnO 2 ;

[0012] The hydrothermal reaction temperature is 140-180°C, for example, it can be 140°C, 145°C, 150°C, 155°C, 160°C, 165°C, 170°C, 175°C or 180°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0013] The hydrothermal reaction time is 10 to 15 hours, for example, it can be 10 hours, 10.5 hours, 11 hours, 11.5 hours, 12 hours, 12.5 hours, 13 hours, 13.5 hours, 14 hours, 14.5 hours or 15 hours, but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0014] (3) dissolving the layered manganese dioxide in water, adding a cobalt salt solution dropwise according to a molar ratio of cobalt atoms to manganese atoms of 1:(1.32-5.28), stirring vigorously for 20-26 hours, washing and drying the obtained product, and keeping it at 300-500°C for 4-6 hours to calcine to obtain a cobalt intercalated manganese dioxide catalyst Co / δ-MnO 2 .

[0015] The above-mentioned Co / Mn molar ratio is 1:(1.32-5.28), for example, it can be 1:1.32, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5 or 1:5.28, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0016] The stirring time is 20 to 26 hours, for example, it can be 20 hours, 21 hours, 22 hours, 23 hours, 23.5 hours, 24 hours, 24.5 hours, 25 hours or 26 hours, but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0017] The calcination temperature is 300-500°C, for example, it can be 300°C, 320°C, 340°C, 350°C, 370°C, 400°C, 430°C, 450°C, 470°C or 500°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0018] The calcination time is 4 to 6 hours, for example, 4 hours, 4.5 hours, 5 hours, 5.5 hours or 6 hours, but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0019] Furthermore, the stirring time in step (1) does not exceed 5 minutes.

[0020] In step (1) of the present invention, the mixing mode of the manganese sulfate solution is controlled to be dropwise added, so that the manganese sulfate solution and the potassium permanganate solution can be fully mixed and uniform. In this step, the stirring time needs to be controlled to be no more than 5 minutes, for example, it can be 5 minutes, 4 minutes, 3 minutes, 2 minutes or other times. If the stirring time is too long, the reaction may occur at room temperature, and the subsequent addition of reagents will cause uneven stirring.

[0021] Furthermore, the molar ratio of potassium permanganate to manganese sulfate is 1:(4-7); preferably, the molar ratio of potassium permanganate to manganese sulfate is preferably 1:5.7.

[0022] Furthermore, in step (2), the hydrothermal reaction temperature is 150-170° C., and the reaction time is 12-14 h.

[0023] Preferably, the hydrothermal reaction temperature is 160°C.

[0024] Preferably, the reaction time is 12 h.

[0025] The hydrothermal reaction is carried out by placing the mixed solution into a polytetrafluoroethylene-lined autoclave and performing the reaction in an oven.

[0026] After the solid product is obtained in step (2) of the present invention, a suction filtration method is used for solid-liquid separation. The density of the solid product is not much different from that of the liquid, and the effect of centrifugal separation is not good. The suction filtration method is adopted, a filter paper with a small pore size is selected, and a suction filtration pump is used to reduce the pressure in the suction filtration bottle to achieve solid-liquid separation. This method is easy to operate and the loss of solid products is small.

[0027] The solid product is filtered and washed with water repeatedly (the number of repetitions is not limited and can be 2, 3, 4 or 5 times or more), and then dried at 60° C. for 24 hours.

[0028] Furthermore, the cobalt salt is selected from cobalt nitrate, cobalt acetate, cobalt chloride or cobalt sulfate.

[0029] Furthermore, in the step (3), during the calcination and molding, the temperature is raised at a rate of 1 to 10°C / min; the calcination temperature is 350 to 450°C, and the time is 4 to 6 hours.

[0030] In step (3) of the present invention, the product before calcination is washed with deionized water for multiple times (2 times, 3 times or 4 times or more) and dried at 60° C. for 24 hours.

[0031] The present invention also provides a novel cobalt intercalated manganese dioxide catalyst prepared according to any one of the preparation methods described above.

[0032] The present invention also provides a novel cobalt intercalated manganese dioxide catalyst prepared according to any of the preparation methods described above for removing Hg from flue gas. 0 Application in.

[0033] Furthermore, the application method is: placing the novel cobalt intercalated manganese dioxide catalyst into the exhaust gas at a certain flow rate, and performing a catalytic reaction at a temperature of 50 to 250°C to remove Hg 0 .

[0034] Furthermore, the waste gas is mercury-containing flue gas from non-ferrous smelting or coal-burning industries.

[0035] Beneficial effects of the present invention:

[0036] (1) The present invention discloses a method for preparing a novel cobalt intercalated manganese dioxide catalyst, which is prepared by using potassium permanganate, manganese sulfate and metal nitrate solution as raw materials, adopting hydrothermal reaction and ion exchange method, and controlling parameters such as hydrothermal temperature and time, as well as calcination temperature rate and insulation time. The preparation process is simple and environmentally friendly, and can meet industrial production requirements.

[0037] The novel cobalt intercalated manganese dioxide catalyst prepared by the present invention is used for the removal of Hg in mercury-containing flue gas such as non-ferrous metallurgy and coal combustion. 0 It can remove Hg in flue gas at a temperature of 50-250℃. 0 Therefore, the design and regulation of the new cobalt-intercalated manganese dioxide catalyst is to achieve efficient Hg removal 0 Provides a broad feasible space.

[0038] (2) The novel cobalt intercalated manganese dioxide catalyst of the present invention catalyzes the removal of Hg 0 The reaction temperature is wide, and more than 99% of Hg can be removed at 50-250℃ 0 , strong adaptability, in high concentration SO 2 The catalytic activity is still high under the atmosphere. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 The novel cobalt intercalated manganese dioxide catalyst Co / δ-MnO prepared in Example 1 2 -1 scanning electron microscope image;

[0040] Figure 2 The cobalt concentrations of the manganese dioxide catalysts intercalated in N 2 Mercury removal performance diagram under atmosphere;

[0041] Figure 3 The different metal intercalated manganese dioxide catalysts in Experimental Example 2 are 2 Mercury removal performance diagram under atmosphere;

[0042] Figure 4 This is a graph showing the effect of different flue gas components on the mercury removal performance of different metal intercalated manganese dioxide catalysts in Experimental Example 3;

[0043] Figure 5 This is a graph showing the effect of different temperatures on the mercury removal performance of the new cobalt intercalated manganese dioxide catalyst in Experimental Example 4;

[0044] Figure 6 For different SO in Experiment 5 2 Effect of concentration on the mercury removal performance of the new cobalt-intercalated manganese dioxide catalyst. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] In order to further understand the present invention, the present invention will be further described in conjunction with the accompanying drawings and embodiments.

[0047] Example 1

[0048] This embodiment provides a method for preparing a novel cobalt intercalated manganese dioxide catalyst, the steps are as follows:

[0049] (1) Weigh 0.4 g of potassium permanganate and dissolve it in 50 mL of distilled water to obtain a potassium permanganate solution; weigh 0.169 g of manganese sulfate and dissolve it in 10 mL of distilled water to obtain a manganese sulfate solution;

[0050] The potassium permanganate solution was transferred to a 100 mL reactor for magnetic stirring, and the manganese sulfate solution was added dropwise for no more than 5 min to mix evenly to obtain a mixed solution;

[0051] (2) The mixed solution was placed in a polytetrafluoroethylene-lined autoclave, and reacted in an oven at 160°C for 12 hours to obtain a precipitated oxide, which was then filtered and washed with water three times, and dried in an oven at 60°C for 24 hours to finally obtain layered manganese dioxide δ-MnO 2 ;

[0052] (3) Weigh 80 mg of layered manganese dioxide and dissolve it in 20 mL of distilled water to obtain a layered manganese dioxide solution. Then, measure 87 μL of a cobalt nitrate solution with a concentration of 1 mol / L and drop it into the layered manganese dioxide solution. Stir at room temperature for 24 hours to obtain a precipitated oxide. Then, filter and wash it with water three times, and dry it at 60° C. for 24 hours. Place it in a muffle furnace and heat it to 350° C. at a rate of 5° C. / min. Keep it warm for 6 hours to finally obtain the product, a novel cobalt intercalated manganese dioxide catalyst Co / δ-MnO 2 -1.

[0053] The novel cobalt intercalated manganese dioxide catalyst Co / δ-MnO prepared in this example 2 -1Scanning electron microscopy analysis was performed to characterize the morphology of the catalyst. Figure 1 As shown, it is shown that the novel cobalt intercalated manganese dioxide catalyst Co / δ-MnO provided by the present invention 2 -1 has a unique nanoflower structure.

[0054] The prepared new cobalt intercalated manganese dioxide catalyst Co / δ-MnO 2 -1 Used to remove Hg from flue gas in non-ferrous smelting or coal-burning industries 0 , the application method is:

[0055] The prepared new cobalt intercalated manganese dioxide catalyst is placed in the flue gas and catalytic reaction is carried out at a temperature of 50-250°C to remove Hg 0 .

[0056] Example 2

[0057] This embodiment provides a method for preparing a novel cobalt intercalated manganese dioxide catalyst, the steps are as follows:

[0058] (1) Weigh 0.4 g of potassium permanganate and dissolve it in 50 mL of distilled water to obtain a potassium permanganate solution; weigh 0.169 g of manganese sulfate and dissolve it in 10 mL of distilled water to obtain a manganese sulfate solution;

[0059] The potassium permanganate solution was transferred to a 100 mL reactor for magnetic stirring, and the manganese sulfate solution was added dropwise for 4 min to mix evenly to obtain a mixed solution;

[0060] (2) The mixed solution was placed in a polytetrafluoroethylene-lined autoclave, and reacted in an oven at 160°C for 12 hours to obtain a precipitated oxide, which was then filtered and washed with water three times, and dried in an oven at 60°C for 24 hours to finally obtain layered manganese dioxide δ-MnO 2 ;

[0061] (3) Weigh 80 mg of layered manganese dioxide and dissolve it in 20 mL of distilled water to obtain a layered manganese dioxide solution. Then, measure 87 μL of a 2 mol / L cobalt nitrate solution and drop it into the layered manganese dioxide solution. Stir at room temperature for 24 hours to obtain a precipitated oxide. Then, filter and wash it with water three times, and dry it at 60° C. for 24 hours. Place it in a muffle furnace and heat it to 350° C. at a rate of 5° C. / min. Keep it warm for 6 hours to finally obtain the product, a novel cobalt intercalated manganese dioxide catalyst Co / δ-MnO 2 -2.

[0062] Example 3

[0063] This embodiment provides a method for preparing a novel cobalt intercalated manganese dioxide catalyst, the steps are as follows:

[0064] (1) Weigh 0.4 g of potassium permanganate and dissolve it in 50 mL of distilled water to obtain a potassium permanganate solution; weigh 0.169 g of manganese sulfate and dissolve it in 10 mL of distilled water to obtain a manganese sulfate solution;

[0065] The potassium permanganate solution was transferred to a 100 mL reactor for magnetic stirring, and the manganese sulfate solution was added dropwise for no more than 5 min to mix evenly to obtain a mixed solution;

[0066] (2) The mixed solution was placed in a polytetrafluoroethylene-lined autoclave, and reacted in an oven at 160°C for 12 hours to obtain a precipitated oxide, which was then filtered and washed with water three times, and dried in an oven at 60°C for 24 hours to finally obtain layered manganese dioxide δ-MnO 2 ;

[0067] (3) Weigh 80 mg of layered manganese dioxide and dissolve it in 20 mL of distilled water to obtain a layered manganese dioxide solution. Then, measure 87 μL of a cobalt acetate solution with a concentration of 1 mol / L and drop it into the layered manganese dioxide solution. Stir at room temperature for 24 hours to obtain a precipitated oxide. Then, filter and wash it with water three times, and dry it at 60° C. for 24 hours. Place it in a muffle furnace and heat it to 350° C. at a rate of 5° C. / min. Keep it warm for 6 hours to finally obtain the product, a novel cobalt intercalated manganese dioxide catalyst Co / δ-MnO 2 -3.

[0068] Comparative Example 1

[0069] The difference between this comparative example and Example 1 is that in step (3), a ferric nitrate solution is added dropwise to the layered manganese dioxide solution. The other steps are the same.

[0070] The final product is iron intercalated manganese dioxide catalyst Fe / δ-MnO 2 .

[0071] Comparative Example 2

[0072] The difference between this comparative example and Example 1 is that in step (3), nickel nitrate solution is added dropwise to the layered manganese dioxide solution. The other steps are the same.

[0073] The final product is nickel intercalated manganese dioxide catalyst Ni / δ-MnO 2 .

[0074] Comparative Example 3

[0075] The difference between this comparative example and Example 1 is that in step (3), no metal salt solution is added, and only the layered manganese dioxide solution is calcined. The other steps are the same.

[0076] The final product is δ-MnO 2 .

[0077] Test Example 1

[0078] 10 mg of each catalyst prepared in Example 1, Example 2, Example 3 and Comparative Example 3 was weighed and placed in a tubular fixed reactor. The reaction temperature was 150° C. and a 500 μg / m 3 Gaseous Hg 0 The simulated flue gas (balance gas is N 2 ) to investigate the effects of different cobalt concentrations of intercalated manganese dioxide catalysts on Hg 0 The removal efficiency is as follows: Figure 2 shown.

[0079] The results show that the catalyst Co / δ-MnO 2 -1. Co / δ-MnO 2 -2. Co / δ-MnO 2 -3 for flue gas Hg 0 The removal efficiency reaches over 99%.

[0080] Test Example 2

[0081] 10 mg of each catalyst prepared in Example 1, Comparative Example 1 and Comparative Example 2 was weighed and placed in a tubular fixed reactor. The reaction temperature was 150° C. and a 500 μg / m 3 Gaseous Hg 0 The simulated flue gas (balance gas is N 2 ) to investigate the effects of different metal intercalated manganese dioxide catalysts on Hg 0 The removal efficiency is as follows: Figure 3 shown.

[0082] The results show that the catalyst Co / δ-MnO 2 -1 for flue gas Hg 0 The removal efficiency reaches over 99%.

[0083] Test Example 3

[0084] 10 mg of each catalyst prepared in Example 1, Comparative Example 1 and Comparative Example 2 was weighed and placed in a tubular fixed reactor. The reaction temperature was 150° C. and gaseous Hg 0 The concentration is 500 μg / m 3 , O 2 The concentration is 6%, SO 2 The simulated flue gas with a concentration of 0.5% (balance gas is N 2 ), investigated the effects of different flue gas components on the mercury removal performance of different metal intercalated manganese dioxide catalysts. Figure 4 shown.

[0085] The results show that the catalyst Co / δ-MnO 2 -1 Effect of different smoke components on Hg 0The removal efficiency reaches over 99%.

[0086] Test Example 4

[0087] 10 mg of the catalyst prepared in Example 1 was weighed and placed in a tubular fixed reactor. The reaction temperatures were 50°C, 100°C, 150°C, 200°C, and 250°C, respectively. A solution containing 500 μg / m 3 Gaseous Hg 0 The simulated flue gas (balance gas is N 2 ), investigated the effect of different temperatures on the mercury removal performance of a new cobalt intercalated manganese dioxide catalyst. The results are as follows Figure 5 shown.

[0088] The results show that the novel cobalt intercalated manganese dioxide catalyst Co / δ-MnO 2 -1 Flue gas Hg at different temperatures 0 The removal efficiency reaches over 99%.

[0089] Test Example 5

[0090] 10 mg of the catalyst prepared in Example 1 was weighed and placed in a tubular fixed reactor. The reaction temperature was 150°C and gaseous Hg 0 The concentration is 500 μg / m 3 , O 2 The concentration is 6%, SO 2 The concentrations of simulated flue gas were 0.05%, 0.1%, 0.3%, 0.5%, 1%, and 3% respectively (balance gas was N 2 ), investigate different SO 2 The effect of concentration on the mercury removal performance of the new cobalt intercalated manganese dioxide catalyst. Figure 6 shown.

[0091] The results show that the novel cobalt intercalated manganese dioxide catalyst Co / δ-MnO 2 -1 in different SO 2 Concentration of Hg in flue gas 0 The removal efficiency reaches over 99%.

[0092] The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions described in the above embodiments, or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, modification, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a novel cobalt intercalated manganese dioxide catalyst, characterized in that: The following steps are involved: (1) dissolving potassium permanganate and manganese sulfate in a molar ratio of 1:(2.5-7) in distilled water to obtain a potassium permanganate solution and a manganese sulfate solution, and adding the manganese sulfate solution dropwise to the potassium permanganate solution under stirring to obtain a mixed solution; (2) subjecting the mixed solution to a hydrothermal reaction at a temperature of 140 to 180° C. for 10 to 15 hours to obtain a solid product, and repeatedly filtering, washing with water, and drying the solid product to obtain layered manganese dioxide δ-MnO2; (3) Dissolve layered manganese dioxide in water, add cobalt salt solution dropwise in a molar ratio of cobalt atoms to manganese atoms of 1:(1.32-5.28), stir vigorously for 20-26 hours, wash and dry the obtained product, keep it at 300-500°C for 4-6 hours, and calcine it to obtain a novel cobalt intercalated manganese dioxide catalyst Co / δ-MnO2.

2. The preparation method according to claim 1, characterized in that: The stirring time in step (1) does not exceed 5 min.

3. The preparation method according to claim 1, characterized in that: The molar ratio of potassium permanganate to manganese sulfate is 1:(4-7).

4. The preparation method according to claim 1, characterized in that: The hydrothermal reaction temperature in step (2) is 150-170° C., and the reaction time is 12-14 hours.

5. The preparation method according to claim 1, characterized in that: The cobalt salt is selected from cobalt nitrate, cobalt acetate, cobalt chloride or cobalt sulfate.

6. The preparation method according to claim 1, characterized in that: In the step (3), during calcination and molding, the temperature is raised at a rate of 1 to 10°C / min; the calcination temperature is 350 to 450°C and the time is 4 to 6 hours.

7. A novel cobalt intercalated manganese dioxide catalyst prepared according to the preparation method according to any one of claims 1 to 6.

8. The novel cobalt intercalated manganese dioxide catalyst prepared by the preparation method according to any one of claims 1 to 6 is used for removing Hg 0 Application in.

9. The use according to claim 8, characterized in that: The novel cobalt intercalated manganese dioxide catalyst is placed in the exhaust gas at a certain flow rate, and the catalytic reaction is carried out at a temperature of 50 to 250°C to remove Hg 0 .

10. The use according to claim 9, characterized in that: The waste gas is mercury-containing flue gas from non-ferrous smelting or coal-burning industries.

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