Porous ceramic scr denitration catalyst and preparation method thereof

Abstract

The present application relates to waste resource utilization, environmental protection catalytic material and atmospheric pollution control field, disclose a kind of porous ceramic SCR denitration catalyst, the porous ceramic SCR denitration catalyst includes porous ceramic carrier, and active component and promoter supported on the surface of porous ceramic carrier;Wherein, the active component contains lanthanum oxychloride;The promoter contains ytterbium oxide and erbium oxide;Raw material in preparation the porous ceramic carrier contains waste steel slag, attapulgite, activated carbon, nano iron powder and forming agent.The porous ceramic SCR denitration catalyst of the application has higher NO x removal efficiency, low cost, with broad market prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of waste resource utilization, environmental protection catalytic materials and air pollution control, in particular, to a porous ceramic SCR denitration catalyst and a preparation method thereof. BACKGROUND

[0002] Nitrogen oxides (NO x ) is one of the main pollutants in the atmosphere, which has great harm to human health and the survival of plants and animals. Excessive emission of NO x far exceeds the self-purification capacity of the atmosphere, seriously endangers the ecological environment, and also causes acid rain and nitrogen deposition, which pollutes and harms the environment. NO x In the atmosphere, it will react with oxygen and other components in the air to form nitrate, and then combine into fine particles (such as PM2.5), causing photochemical air pollution. Therefore, it is crucial to control NO x .

[0003] NH3 selective catalytic reduction (SCR) removal of NO x has the characteristics of mature technology and high removal efficiency, and is widely used at home and abroad. At present, the commercial catalysts used are generally vanadium-tungsten-titanium series denitration catalysts, but such catalysts have high requirements for operating temperature, and the best operating temperature is generally 350-400℃. In industrial production, because the desulfurization and dust removal device is arranged after the denitration device, sulfides and dust in the flue gas will have a toxic effect on the denitration catalyst, resulting in a significant reduction in the service life of the catalyst. If the denitration device is placed at the tail end of the desulfurization and dust removal device, the problem of reduced catalyst life can be avoided. However, after desulfurization and dust removal, the flue gas temperature is about 150℃, and the existing commercial catalysts are not suitable for low-temperature conditions for removal of nitrogen oxides. Therefore, it is of great significance to develop a denitration catalyst that meets the actual industrial flue gas conditions under low-temperature conditions.

[0004] There are patents that have disclosed low-temperature SCR denitration catalysts and preparation methods. Patent application CN201811441127.1 discloses a method for improving the water resistance and sulfur resistance of a manganese-based low-temperature SCR denitration catalyst. The method uses hydrophobic polytetrafluoroethylene as a wrapping or doping material, and after simple dispersion in a reactor containing anhydrous ethanol, and mixing and stirring with the manganese-based catalyst, filtration, drying and calcination, a manganese-based low-temperature SCR denitration catalyst with excellent water resistance and sulfur resistance can be prepared. The catalyst effectively improves the water resistance and sulfur resistance of the catalyst, but the NO xThe removal efficiency is only 80%, and the NOx removal efficiency still needs to be improved. Patent CN112742413B discloses a low-temperature SCR denitration catalyst and a preparation method and application thereof. The low-temperature SCR denitration catalyst comprises a carrier, an active component and a rare earth oxide. The carrier is a doped titanium dioxide nanotube doped with a metal oxide. The active component is a mixture of MnO x and FeO y The catalyst has excellent water resistance, sulfur resistance and stability, and can be applied to low-temperature denitration of high-water-content flue gas such as natural gas. However, the use of titanium dioxide nanotubes in the catalyst increases the economic cost and makes it difficult to achieve large-scale industrial application. SUMMARY

[0005] The purpose of the present application is to overcome the low removal efficiency of the SCR denitration catalyst in the prior art and provide a porous ceramic SCR denitration catalyst and a preparation method thereof. The porous ceramic SCR denitration catalyst has a high NO x removal efficiency.

[0006] To achieve the above-mentioned purpose, the first aspect of the present application provides a porous ceramic SCR denitration catalyst, which comprises a porous ceramic carrier, and an active component and a catalyst promoter supported on the surface of the porous ceramic carrier.

[0007] The active component contains lanthanum oxychloride.

[0008] The catalyst promoter contains ytterbium oxide and erbium oxide.

[0009] The raw materials for preparing the porous ceramic carrier contain waste steel slag, attapulgite, activated carbon, nano-iron powder and a forming agent.

[0010] Preferably, the weight ratio of the porous ceramic carrier, the active component and the catalyst promoter is 100:5-15:2-8.

[0011] Preferably, the weight ratio of the ytterbium oxide and the erbium oxide is 1:0.2-0.5.

[0012] Preferably, the forming agent is polyvinyl alcohol.

[0013] The second aspect of the present application provides a preparation method of the above-mentioned porous ceramic SCR denitration catalyst, which comprises the following steps:

[0014] (1) mixing waste steel slag, attapulgite, activated carbon, nano-iron powder and a forming agent solution, granulating, and then calcining to obtain a porous ceramic carrier;

[0015] (2) mixing a lanthanum salt with water to obtain an active component precursor solution; (3) mixing the active component precursor solution with a catalyst promoter solution to obtain a catalyst precursor solution;

[0016] (3) mixing ytterbium salt and erbium salt with water to obtain a cocatalyst precursor solution;

[0017] (4) mixing the porous ceramic carrier with the active component precursor solution, then stirring to dryness at 60-80℃, then performing first calcination, cooling the product obtained by first calcination, then mixing with hydrochloric acid solution, adsorbing for 1-2h, then performing second calcination, then mixing the product obtained by second calcination with the cocatalyst precursor solution, then stirring to dryness at 60-80℃, and finally performing third calcination.

[0018] Preferably, in step (1), the weight ratio of the waste steel slag, attapulgite, activated carbon, nano-iron powder and molding agent solution is 60-80:10-20:5-10:5-10:5-10.

[0019] Preferably, the molding agent solution is a polyvinyl alcohol solution.

[0020] Preferably, the concentration of the polyvinyl alcohol solution is 5-10% by weight.

[0021] Preferably, the calcination conditions include a temperature of 1100-1300℃ and a time of 2-4h.

[0022] Preferably, in step (2), the lanthanum salt is lanthanum nitrate hexahydrate.

[0023] Preferably, in step (3), the ytterbium salt is ytterbium chloride hexahydrate.

[0024] Preferably, the erbium salt is erbium chloride hexahydrate.

[0025] Preferably, in step (4), the first calcination conditions include a temperature of 400-500℃ and a time of 2-4h.

[0026] Preferably, the concentration of the hydrochloric acid solution is 20-30% by weight.

[0027] Preferably, in step (4), the second calcination conditions include a temperature of 500-600℃ and a time of 2-3h.

[0028] Preferably, in step (4), the third calcination conditions include a temperature of 400-600℃ and a time of 2-4h.

[0029] The application takes porous ceramics fired by waste steel slag, attapulgite, activated carbon, nano-iron powder and a forming agent as a carrier, wherein the activated carbon is a pore-forming agent, and the porous ceramics carrier is prepared by calcination and pore formation, and the porous ceramics SCR denitration catalyst has the advantages that: (1) the nano-iron powder is added to the catalyst carrier, and the excellent heat conduction performance of the nano-iron powder is beneficial to quickly conducting out the heat released in the selective catalytic reduction process of NH3, accelerating the chemical reaction efficiency, and improving the NO x removal efficiency; (2) the catalyst has a rich pore structure and high internal porosity, and the porous structure is beneficial to loading the active components on the surface of the catalyst, prolonging the contact time of the reaction gas and the active components, and thus improving the NO x removal efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 The activity diagram of the catalyst prepared in Examples 1-3;

[0031] Figure 2 The activity diagram of the catalyst prepared in Comparative Examples 1-3. DETAILED DESCRIPTION

[0032] The specific embodiments of the application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely intended to illustrate and explain the application, and are not intended to limit the application.

[0033] The endpoints of the ranges and any values disclosed herein are not limited to the precise values stated. The endpoints of the ranges and the values are approximate values and should be understood to include values approximately near these ranges and values within these ranges. For ranges with endpoints, each endpoint is disclosed separately from the other. For ranges with endpoints, each endpoint is disclosed separately from the other. These and other aspects of the application will be better understood from the detailed description taken in conjunction with the accompanying drawings.

[0034] The first aspect of the application provides a porous ceramics SCR denitration catalyst, which comprises a porous ceramics carrier, and an active component and a promoter supported on the surface of the porous ceramics carrier.

[0035] The active component contains lanthanum oxychloride.

[0036] The promoter contains ytterbium oxide and erbium oxide.

[0037] The raw materials for preparing the porous ceramics carrier contain waste steel slag, attapulgite, activated carbon, nano-iron powder and a forming agent.

[0038] In the porous ceramics SCR denitration catalyst described in the application, the forming agent is preferably polyvinyl alcohol.

[0039] In the porous ceramic SCR denitration catalyst, the weight ratio of the porous ceramic carrier, the active component and the promoter is preferably 100:5-15:2-8, and can be 100:5:2, 100:5:4, 100:5:6, 100:5:8, 100:10:2, 100:10:4, 100:10:6, 100:10:8, 100:15:2, 100:15:4, 100:15:6 or 100:15:8.

[0040] In the porous ceramic SCR denitration catalyst, the weight ratio of the ytterbium oxide and the erbium oxide is preferably 1:0.2-0.5, and can be 1:0.2, 1:0.3, 1:0.4 or 1:0.5.

[0041] In the porous ceramic SCR denitration catalyst, the forming agent is polyvinyl alcohol.

[0042] The second aspect of the present application provides a preparation method of the above porous ceramic SCR denitration catalyst, which comprises the following steps:

[0043] (1) mixing waste steel slag, attapulgite, activated carbon, nano-iron powder and a forming agent solution, granulating, and then calcining to obtain a porous ceramic carrier;

[0044] (2) mixing a lanthanum salt with water to obtain an active component precursor solution;

[0045] (3) mixing a ytterbium salt and an erbium salt with water to obtain a promoter precursor solution;

[0046] (4) mixing the porous ceramic carrier with the active component precursor solution, stirring at 60-80°C until dry, then performing first calcination, cooling the product obtained by the first calcination, mixing with a hydrochloric acid solution, adsorbing for 1-2h, then performing second calcination, and then mixing the product obtained by the second calcination with the promoter precursor solution, stirring at 60-80°C until dry, and finally performing third calcination.

[0047] In the preparation method, in order to obtain the catalyst, the weight ratio of the waste steel slag, the attapulgite, the activated carbon, the nano-iron powder and the forming agent solution is preferably controlled to be 60-80:10-20:5-10:5-10:5-10 in step (1).

[0048] In step (1), the particle size of the waste steel slag, the attapulgite, the activated carbon and the nano-iron powder used is preferably 60-80 mesh.

[0049] In the preparation method of the present application, in step (1), the solution of the molding agent is a polyvinyl alcohol solution.

[0050] In the present application, the concentration of the polyvinyl alcohol solution is preferably 5-10% by weight, and can be 5%, 6%, 7%, 8%, 9% or 10% by weight.

[0051] In the preparation method of the present application, in step (1), the granulation method can be a common granulation method in the art, and in a specific embodiment, a rolling molding method can be used for granulation.

[0052] In the preparation method of the present application, in step (1), the calcination conditions include a temperature of 1100-1300℃ and a time of 2-4h, and specifically, the temperature can be 1100℃, 1150℃, 1200℃, 1250℃ or 1300℃, and the time can be 2h, 2.5h, 3h, 3.5h or 4h.

[0053] In the preparation method of the present application, in step (2), the lanthanum salt is lanthanum nitrate hexahydrate, and the amount of water used is not particularly limited, and the lanthanum nitrate hexahydrate can be completely dissolved.

[0054] In the preparation method of the present application, in step (3), the ytterbium salt is ytterbium chloride hexahydrate.

[0055] In the preparation method of the present application, in step (3), the erbium salt is erbium chloride hexahydrate, and in this step, the amount of water used is not particularly limited, and the ytterbium chloride hexahydrate and the erbium chloride hexahydrate can be completely dissolved.

[0056] In the preparation method of the present application, in step (4), after the porous ceramic carrier is mixed with the active component precursor solution, the stirring temperature until dryness can be 60℃, 65℃, 70℃, 75℃ or 80℃.

[0057] In the preparation method of the present application, in step (4), the first calcination conditions include a temperature of 400-500℃ and a time of 2-4h, and specifically, the temperature can be 400℃, 420℃, 440℃, 460℃, 480℃ or 500℃, and the time can be 2h, 2.5h, 3h, 3.5h or 4h.

[0058] In the preparation method of the present application, in step (4), the concentration of the hydrochloric acid solution is 20-30% by weight, and can be 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29% or 30% by weight.

[0059] In the preparation method, in step (4), the second calcination has a temperature of 500-600 DEG C and a time of 2-3h, and specifically, the temperature can be 500 DEG C, 510 DEG C, 520 DEG C, 530 DEG C, 540 DEG C, 550 DEG C, 560 DEG C, 570 DEG C, 580 DEG C, 590 DEG C or 600 DEG C, and the time can be 2h, 2.1h, 2.2h, 2.3h, 2.4h, 2.5h, 2.6h, 2.7h, 2.8h, 2.9h or 3h.

[0060] In step (4) of the application, after the product obtained by the second calcination is mixed with the promoter precursor solution, the stirring temperature until dryness can be 60 DEG C, 65 DEG C, 70 DEG C, 75 DEG C or 80 DEG C.

[0061] In step (4) of the application, in step (4), the third calcination has a temperature of 400-600 DEG C and a time of 2-4h, and specifically, the temperature can be 400 DEG C, 450 DEG C, 500 DEG C, 550 DEG C or 600 DEG C, and the time can be 2h, 2.5h, 3h, 3.5h or 4h.

[0062] Compared with the prior art, the technical scheme of the application has the following beneficial effects:

[0063] (1) The SCR denitration catalyst prepared by the application can not only realize high value-added utilization of industrial waste, but also improve the migration and adsorption of reaction gas in the catalytic reaction process by utilizing the rich pore structure, high specific surface area and porosity of the catalyst;

[0064] (2) The excellent heat conduction performance of the nano iron powder can quickly conduct the heat generated in the reaction process, accelerate the reaction efficiency and improve the NO x removal efficiency, so that the catalyst can also exhibit good NO x removal efficiency at low temperature;

[0065] (3) The SCR denitration catalyst of the application has high NO x removal efficiency at low temperature, can be applied to the tail end of flue gas treatment, avoids reheating of flue gas, is suitable for industrial flue gas tail gas denitration treatment, and has a wide market prospect due to the wide source of catalyst raw materials, high mechanical strength, low cost and strong resistance to poisoning.

[0066] The application will be described in detail below through examples, but the scope of protection of the application is not limited thereto.

[0067] The waste steel slag used in the following examples and comparative examples is from Zhongye Changtian International Engineering Co., Ltd., the attapulgite is purchased from Shanghai Yuanye Biotechnology Co., Ltd., the product number is S28335, the activated carbon is purchased from Sinopharm Chemical Reagent Co., Ltd., the CAS number is 7440-44-0, the nano-iron powder is purchased from Shanghai Jizhishe Biotechnology Co., Ltd., the CAS number is 7439-89-6, and the polyvinyl alcohol is purchased from Sinopharm Chemical Reagent Co., Ltd., the CAS number is 9002-89-5;

[0068] The particle sizes of the waste steel slag, attapulgite, activated carbon and nano-iron powder used in the following examples and comparative examples are all 60-80 mesh.

[0069] Example 1

[0070] (1) Preparation of catalyst carrier

[0071] 60 g of waste steel slag, 10 g of attapulgite, 5 g of activated carbon and 5 g of nano-iron powder were weighed and uniformly mixed, 5 g of polyvinyl alcohol solution with a concentration of 5% by weight was added, and the mixture was rapidly and fully stirred, then the mixture was granulated by rolling forming method, and then transferred to a muffle furnace for calcination at 1100°C for 4 h in air atmosphere to prepare a porous ceramic carrier.

[0072] (2) Preparation of active component precursor solution

[0073] 1.0492 g of lanthanum nitrate hexahydrate was weighed and dissolved in 5 mL of deionized water to obtain an active component precursor solution;

[0074] (3) Preparation of catalyst precursor solution

[0075] 0.3278 g of ytterbium chloride hexahydrate and 0.0665 g of erbium chloride hexahydrate were dissolved in 5 mL of deionized water to obtain a catalyst precursor solution;

[0076] (4) Preparation of catalyst

[0077] Take 10 g of the porous ceramic carrier prepared in step (1) and mix with the active component precursor ion solution prepared in step (2), then transfer to a constant temperature stirrer, stir at 60°C until dry, and then place in a muffle furnace for first firing (temperature 400°C, time 4h) in an air atmosphere, cool the product obtained after the first firing, and then place in 5mL of a 20wt% concentration hydrochloric acid solution, mix and adsorb for 1h, then transfer to a muffle furnace for second firing (temperature 500°C, time 3h) in an air atmosphere, then cool the product obtained after the second firing, and add the promoter precursor solution prepared in step (3), mix uniformly, then transfer to a constant temperature stirrer, stir at 60°C until dry, and finally transfer to a muffle furnace for third firing (temperature 400°C, time 4h) in an air atmosphere, to obtain a porous ceramic SCR denitration catalyst A1, wherein the active component is lanthanum oxychloride and the promoter is ytterbium oxide and erbium oxide.

[0078] Example 2

[0079] (1) Catalyst carrier preparation

[0080] Take 80 g of waste steel slag, 20 g of attapulgite, 10 g of activated carbon, and 10 g of nano-iron powder, mix well, add 10 g of a 10wt% concentration polyvinyl alcohol solution, mix well, and then use a rolling forming method to granulate, transfer to a muffle furnace, and calcine at 1300°C for 2h in an air atmosphere to prepare a porous ceramic carrier;

[0081] (2) Preparation of active component precursor solution

[0082] Dissolve 3.1475 g of lanthanum nitrate hexahydrate in 5 mL of deionized water, stir well to obtain an active component precursor solution;

[0083] (3) Preparation of promoter precursor solution

[0084] Dissolve 1.0488 g of ytterbium chloride hexahydrate and 0.5322 g of erbium chloride hexahydrate in 5 mL of deionized water, stir well to obtain a promoter precursor solution;

[0085] (4) Catalyst preparation

[0086] Take 10 g of the porous ceramic carrier prepared in step (1) and mix with the active component precursor ion solution prepared in step (2), then transfer to a constant temperature stirrer, stir at 80°C until dry, and then place in a muffle furnace for first firing (temperature 500°C, time 2h) in an air atmosphere, cool the product obtained after the first firing, and then place in 5mL of a 30wt% concentration hydrochloric acid solution, mix and adsorb for 1h, then transfer to a muffle furnace for second firing (temperature 600°C, time 2h) in an air atmosphere, then cool the product obtained after the second firing, and add the promoter precursor solution prepared in step (3), mix uniformly, then transfer to a constant temperature stirrer, stir at 80°C until dry, and finally transfer to a muffle furnace for third firing (temperature 600°C, time 2h) in an air atmosphere, to obtain a porous ceramic SCR denitration catalyst A2, wherein the active component is lanthanum oxychloride and the promoter is ytterbium oxide and erbium oxide.

[0087] Example 3

[0088] (1) Catalyst carrier preparation

[0089] Take 70g of waste steel slag, 15g of attapulgite, 7.5g of activated carbon, and 7.5g of nano-iron powder, mix well, add 7.5g of a 7.5wt% concentration polyvinyl alcohol solution, mix well, and then use a rolling forming method to granulate, transfer to a muffle furnace for calcination at 1200°C for 2h in an air atmosphere, to prepare a porous ceramic carrier;

[0090] (2) Preparation of active component precursor solution

[0091] Dissolve 2.0983g of lanthanum nitrate hexahydrate in 5mL of deionized water, stir until uniform, to obtain an active component precursor solution;

[0092] (3) Preparation of promoter precursor solution

[0093] Dissolve 0.7284g of ytterbium chloride hexahydrate and 0.2587g of erbium chloride hexahydrate in 5mL of deionized water, stir until uniform, to obtain a promoter precursor solution;

[0094] (4) Catalyst preparation

[0095] Take 10 g of the porous ceramic carrier prepared in step (1) and mix with the active component precursor ion solution prepared in step (2), then transfer to a constant temperature stirrer and stir at 70°C until dry, then place in a muffle furnace and perform first baking (temperature 450°C, time 3h) in an air atmosphere, then cool the product of the first baking and place in 5 mL of a 30 wt% hydrochloric acid solution, mix and adsorb for 1.5h, then transfer to a muffle furnace and perform second baking (temperature 550°C, time 2.5h) in an air atmosphere, then cool the product of the second baking and add the promoter precursor solution prepared in step (3), mix well and then transfer to a constant temperature stirrer and stir at 70°C until dry, and finally transfer to a muffle furnace and perform third baking (temperature 500°C, time 3h) in an air atmosphere, to obtain the porous ceramic SCR denitration catalyst A3, in which the active component is lanthanum oxychloride and the promoter is ytterbium oxide and erbium oxide.

[0096] Comparative Example 1

[0097] The method of Example 1 is followed, except that in step (1) no nano-iron powder is used, to obtain the porous ceramic SCR denitration catalyst D1.

[0098] Comparative Example 2

[0099] The method of Example 1 is followed, except that in step (4) the product of the first baking is not placed in a hydrochloric acid solution for adsorption, but is cooled and directly subjected to second baking, to obtain the porous ceramic SCR denitration catalyst D2.

[0100] Comparative Example 3

[0101] The method of Example 1 is followed, except that in step (3) no ytterbium chloride hexahydrate is added, but 0.0665 g of erbium chloride hexahydrate is dissolved in 5 mL of deionized water to obtain the promoter precursor solution, to obtain the porous ceramic SCR denitration catalyst D3.

[0102] Test Example

[0103] Take 2 mL of the porous ceramic SCR denitration catalysts A1-A3, D1-D3 respectively, and load into a catalyst performance evaluation reaction device, which has a quartz tube with an inner diameter of 10 mm, and pass a reaction gas through it for activity evaluation, the reaction gas composition being: NH3(500 ppm), NO (500 ppm), O2(10 vol.%), N2as carrier gas, the reaction gas flow rate being 400 mL / min, the reaction test temperature range being 120-300°C, and the specific content of the outlet gas is detected respectively, and the NOxconversion rate is calculated according to the detection results. xThe removal efficiency is shown in the following table: Figure 1 and Figure 2 as shown in the following table.

[0104] According to Figure 1 and Figure 2 A1 has the NO x removal efficiency of 85.4%, and the NO x removal efficiency is all greater than 90%, and the highest can reach 100%.

[0105] A2 has the NO x removal efficiency of 89.5%, and the NO x removal efficiency is all greater than 92%, and the highest can reach 100%.

[0106] A3 has the NO x removal efficiency of 87%, and the NO x removal efficiency is all greater than 90%, and the highest can reach 100%.

[0107] D1 has the NO x removal efficiency of 87%, and the NO

[0108] D2 has the NO x removal efficiency of 87%, and the NO

[0109] D3 has the NO x removal efficiency of 87%, and the NO

[0110] It can be seen from the above results that the porous ceramic SCR denitration catalyst obtained by the present application has low application temperature, high NO x removal efficiency, the NO x removal efficiency is greater than 85%, the NO x removal efficiency is all greater than 90%, and the highest can reach 100%, and the raw material source is extensive, the price is low, the preparation process is simple, and the present application has wide market application prospect.

[0111] The preferred embodiments of the present application are described in detail above, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including that each technical feature is combined in any other suitable manner. These simple modifications and combinations should also be considered as disclosed by the present application and fall within the protection scope of the present application.

Claims

1. A porous ceramic SCR De-NOx catalyst, characterized by, The porous ceramic SCR denitration catalyst comprises a porous ceramic carrier, and an active component and a catalyst promoter supported on the surface of the porous ceramic carrier; The active component contains lanthanum oxychloride; The catalyst promoter contains ytterbium oxide and erbium oxide, and the weight ratio of the ytterbium oxide to the erbium oxide is 1:0.2-0.5; The raw material for preparing the porous ceramic carrier contains waste steel slag, attapulgite, activated carbon, nano iron powder and a forming agent. 2.The porous ceramic SCR De-NOx catalyst according to claim 1, characterized in that, The weight ratio of the porous ceramic carrier, the active component and the catalyst promoter is 100:5-15:2-8.

3. The porous ceramic SCR de-NOx catalyst according to claim 1 or 2, characterized in that, The forming agent is polyvinyl alcohol.

4. The method of producing a porous ceramic SCR De-NOx catalyst according to any one of claims 1 to 3, characterized in that, The method comprises the following steps: (1) mixing the waste steel slag, the attapulgite, the activated carbon, the nano iron powder and the forming agent solution, then granulating, and then calcining to obtain the porous ceramic carrier; (2) mixing a lanthanum salt with water to obtain an active component precursor solution; (3) mixing a ytterbium salt and an erbium salt with water to obtain a catalyst promoter precursor solution; (4) mixing the porous ceramic carrier with the active component precursor solution, then stirring at 60-80℃ until dry, then performing first roasting, cooling the product obtained by the first roasting, then mixing with a hydrochloric acid solution, adsorbing for 1-2h, then performing second roasting, and finally mixing the product obtained by the second roasting with the catalyst promoter precursor solution, then stirring at 60-80℃ until dry, and then performing third roasting.

5. The preparation method according to claim 4, characterized in that, In step (1), the weight ratio of the waste steel slag, the attapulgite, the activated carbon, the nano iron powder and the forming agent solution is 60-80:10-20:5-10:5-10:5-10.

6. The preparation method according to claim 4, characterized in that, The forming agent solution is a polyvinyl alcohol solution.

7. The preparation method according to claim 6, characterized in that, The concentration of the polyvinyl alcohol solution is 5-10% by weight.

8. The method of any one of claims 4-7, wherein, In step (1), the calcining conditions include a temperature of 1100-1300℃ and a time of 2-4h.

9. The production method according to claim 4 or 5, characterized by, In step (2), the lanthanum salt is lanthanum nitrate hexahydrate.

10. The method of claim 4, wherein, In step (3), the ytterbium salt is ytterbium chloride hexahydrate.

11. The production method according to claim 4 or 10, characterized by, In step (3), the erbium salt is erbium chloride hexahydrate.

12. The method of claim 4, wherein, In step (4), the first roasting conditions include a temperature of 400-500℃ and a time of 2-4h.

13. The production method according to claim 4 or 12, characterized by, In step (4), the concentration of the hydrochloric acid solution is 20-30% by weight.

14. The production method according to claim 4 or 12, characterized by, In step (4), the second roasting conditions include a temperature of 500-600℃ and a time of 2-3h.

15. The production method according to claim 4 or 12, characterized by, In step (4), the third roasting conditions include a temperature of 400-600℃ and a time of 2-4h.

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