Assistant formula for improving activity of supported catalyst, preparation method and regeneration method

Abstract

The invention discloses an auxiliary agent formula for improving activity of a supported catalyst, a preparation method and a regeneration method, and the auxiliary agent formula for improving activity of the supported catalyst comprises the following components in percentage by mass: 1-10% of monoethanolamine, 20-40% of triethanolamine, 10-20% of alkylphenol polyoxyethylene ether and 40-50% of a macromolecular leveling agent. According to the additive formula for improving the activity of the supported catalyst, the monoethanolamine and the triethanolamine stabilize the precursor, the alkylphenol polyoxyethylene ether enhances the permeability, and the macromolecular leveling agent inhibits agglomeration, so that the activity and the stability of the catalyst are remarkably improved.

Description

Technical Field

[0001] The invention relates to the technical field of SCR catalyst formulation, and more specifically to an auxiliary agent formulation for improving the activity of a supported catalyst, a preparation method and a regeneration method. Background Art

[0002] Selective catalytic reduction technology (SCR) is a highly efficient denitrification technology widely used in industrial flue gas treatment. Its core part is the SCR denitrification catalyst. During long-term use, the SCR denitrification catalyst will gradually lose its activity due to the fly ash and other poisoning components in the flue gas covering the active sites on the catalyst surface. Therefore, the SCR denitrification catalyst needs to be replaced or regenerated after a certain number of years of use. During the catalyst regeneration process, strong acids, strong bases and other chemical agents are first used to clean the catalyst surface to remove the fly ash and poisoning components (Na, Mg, Ca, As, etc.) covering the catalyst surface. Finally, a solution containing an active component precursor (the active component of the SCR denitrification catalyst is generally V 2 O 5 and WO 3 The catalyst unit is regenerated by impregnating the active liquid of the catalyst unit with the active liquid of the catalyst unit, and the catalyst activity is restored to the initial state after drying, calcination and activation. In the actual production process, it is found that the active components are unevenly dispersed on the catalyst surface after impregnation with the active liquid, and the active component loading amount deviates from the calculated value, which leads to the decrease of the activity of the SCR catalyst after active loading. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art to a certain extent. To this end, the present invention proposes an auxiliary agent formula for improving the activity of a supported catalyst, wherein monoethanolamine and triethanolamine stabilize the precursor, alkylphenol polyoxyethylene ether enhances permeability, and a macromolecular leveling agent inhibits agglomeration, thereby significantly improving the activity and stability of the catalyst.

[0004] The invention also provides an active solution having the above auxiliary agent formula for improving the activity of the supported catalyst.

[0005] The present invention also provides a catalyst regeneration method using the auxiliary agent formula for improving the activity of the supported catalyst.

[0006] The technical scheme adopted by the present invention is to provide an auxiliary agent formula for improving the activity of a supported catalyst, wherein the components are as follows by mass percentage: 1-10% monoethanolamine, 20-40% triethanolamine, 10-20% alkylphenol polyoxyethylene ether, and 40-50% macromolecular leveling agent.

[0007] After adopting the above formula, the synergistic effect of monoethanolamine and triethanolamine stabilizes the active component precursor through chelation, making it more stable in the solution, thereby avoiding loss during the impregnation and drying process. The addition of alkylphenol polyoxyethylene ether reduces the surface tension of the active solution, which can better penetrate into the microporous structure of the catalyst surface, ensuring that the active components are evenly covered in the catalyst micropores. The macromolecular leveling agent plays a role in inhibiting the agglomeration of the active components during the drying and calcining process, so that the loaded active components are evenly distributed on the catalyst surface, thereby improving the activity and stability of the catalyst.

[0008] According to one embodiment of the present invention, the macromolecular leveling agent is a non-ionic leveling agent; due to its non-ionic characteristics, the macromolecular leveling agent does not produce charge interference in the solution, which enables it to maintain good stability and dispersibility under different pH conditions. Its macromolecular structure can form a stable coating layer in the active solution, so that the active component precursor can be more evenly attached to the catalyst surface during the impregnation process.

[0009] According to one embodiment of the present invention, the non-ionic leveling agent is at least one of sodium polyacrylate and polyethylene glycol ether; sodium polyacrylate is a high molecular polymer with excellent water solubility and dispersibility, and can effectively stabilize the active component precursor in the active liquid to prevent its precipitation or agglomeration in the solution.

[0010] Polyethylene glycol ether type leveling agents can enhance the permeability and wettability of the active solution by reducing the surface tension of the solution, making it easier for the active components to enter the microporous structure of the catalyst, thereby improving the uniformity of the load. In addition, polyethylene glycol ether type leveling agents can also form a uniform molecular film during the drying and calcining process, gradually decomposing as the temperature rises, providing a stable drying environment for the active components and avoiding agglomeration caused by uneven local concentration during the drying process.

[0011] When sodium polyacrylate and polyglycol ether type leveling agents are used in conjunction, they can combine their respective advantages: sodium polyacrylate provides good dispersion stability, and polyglycol ether type leveling agents improve the permeability and uniformity of the solution.

[0012] A method for preparing an auxiliary agent solution for improving the activity of a supported catalyst comprises mixing any of the auxiliary agent formulas described above to prepare a solution.

[0013] According to one embodiment of the present invention, the following steps are included:

[0014] S11, sequentially adding monoethanolamine, triethanolamine, alkylphenol polyoxyethylene ether, and macromolecular leveling agent into deionized water in proportion;

[0015] S12, stirring to obtain a uniform auxiliary agent solution.

[0016] According to an embodiment of the present invention, the step S12 is specifically stirring at room temperature for 2-3 hours to form a uniform solution.

[0017] A method for regenerating a catalyst comprises the following steps:

[0018] S21, add oxalic acid, ammonium metavanadate, and ammonium metatungstate to deionized water in sequence, and after they are completely dissolved, add 0.1-1% of any of the above-mentioned mixed auxiliary agent solutions, and mix them evenly to obtain a final active solution;

[0019] S22, placing the regenerated catalyst unit into an active solution mixed with an additive, ultrasonically immersing it, and then draining it;

[0020] S23, placing the drained catalyst unit into calcination.

[0021] According to one embodiment of the present invention, the ultrasonic immersion time in step S22 is 10-15 minutes.

[0022] According to one embodiment of the present invention, the calcination temperature in step S23 is 350°C.

[0023] According to one embodiment of the present invention, the calcination time in step S23 is 3 hours. DETAILED DESCRIPTION

[0024] The embodiments of the present invention are described in detail below, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0025] Embodiment 1

[0026] The denitration efficiency and activity characterization conditions of the catalyst in this embodiment are as follows:

[0027]

[0028]

[0029] Characterization results of denitrification efficiency and activity of catalyst unit before regeneration:

[0030]

[0031] Embodiment 1

[0032] This embodiment discloses a catalyst regeneration method, which comprises the following steps:

[0033] S21, add oxalic acid, ammonium metavanadate, and ammonium metatungstate to deionized water in sequence, and after they are completely dissolved, add 0.1-1% mixed auxiliary solution, mix evenly to obtain a final active solution, wherein the components of the mixed auxiliary solution are as follows by mass percentage: 10% monoethanolamine, 20% triethanolamine, 20% alkylphenol polyoxyethylene ether, and 50% sodium polyacrylate;

[0034] S22, placing the regenerated catalyst unit into an active solution mixed with an additive and ultrasonically immersing it for 10 minutes, and then draining it;

[0035] S23, placing the drained catalyst unit into a calcining furnace at 350° C. and calcining for 3 hours.

[0036] Embodiment 2

[0037] This embodiment discloses a catalyst regeneration method, which comprises the following steps:

[0038] S21, add oxalic acid, ammonium metavanadate, and ammonium metatungstate to deionized water in sequence, and after they are completely dissolved, add 0.1-1% mixed auxiliary solution, mix evenly to obtain a final active solution, wherein the components of the mixed auxiliary solution are as follows by mass percentage: 10% monoethanolamine, 20% triethanolamine, 20% alkylphenol polyoxyethylene ether, and 50% polyethylene glycol ether type;

[0039] S22, placing the regenerated catalyst unit into an active solution mixed with an additive and ultrasonically immersing it for 10 minutes, and then draining it;

[0040] S23, placing the drained catalyst unit into a calcining furnace at 350° C. and calcining for 3 hours.

[0041] Embodiment 3

[0042] This embodiment discloses a catalyst regeneration method, which comprises the following steps:

[0043] S21, add oxalic acid, ammonium metavanadate, and ammonium metatungstate to deionized water in turn, and after they are completely dissolved, add 0.1-1% mixed auxiliary solution, mix evenly to obtain a final active solution, wherein the components of the mixed auxiliary solution are as follows by mass percentage: 1% monoethanolamine, 39% triethanolamine, 10% alkylphenol polyoxyethylene ether, 25% sodium polyacrylate, and 25% polyethylene glycol ether type;

[0044] S22, placing the regenerated catalyst unit into an active solution mixed with an additive and ultrasonically immersing it for 10 minutes, and then draining it;

[0045] S23, placing the drained catalyst unit into a calcining furnace at 350° C. and calcining for 3 hours.

[0046] Comparative Example 1

[0047] This embodiment discloses a catalyst regeneration method, which comprises the following steps:

[0048] S21, adding oxalic acid, ammonium metavanadate, and ammonium metatungstate to deionized water in sequence to prepare an active solution;

[0049] S22, placing the regenerated catalyst unit into the active solution for ultrasonic immersion for 10 minutes and then draining;

[0050] S23, placing the drained catalyst unit into a calcining furnace at 350° C. and calcining for 3 hours.

[0051] Test example

[0052] The denitration efficiency and activity of the regenerated catalyst units in Example 1 and Comparative Example 1 were characterized respectively, and the results are as follows:

[0053]

[0054] In summary, the invention proposes an additive formula for improving the activity of a supported catalyst. Monoethanolamine and triethanolamine stabilize the precursor, alkylphenol polyoxyethylene ether enhances permeability, and a macromolecular leveling agent inhibits agglomeration, thereby significantly improving the activity and stability of the catalyst.

[0055] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A formulation of an additive for improving the activity of a supported catalyst, characterized in that: The components are as follows by mass percentage: 1-10% monoethanolamine, 20-40% triethanolamine, 10-20% alkylphenol polyoxyethylene ether, and 40-50% macromolecular leveling agent.

2. The additive formulation for improving the activity of a supported catalyst according to claim 1, characterized in that: The macromolecular leveling agent is a non-ionic leveling agent.

3. The additive formulation for improving the activity of a supported catalyst according to claim 2, characterized in that: The nonionic leveling agent is at least one of sodium polyacrylate and polyethylene glycol ether.

4. A method for preparing a solution for improving the activity of a supported catalyst, characterized in that: The auxiliary agent formulation according to any one of claims 1 to 3 is mixed to prepare a solution.

5. The method for preparing a solution for improving the activity of a supported catalyst according to claim 4, characterized in that: The following steps are involved: S11, sequentially adding monoethanolamine, triethanolamine, alkylphenol polyoxyethylene ether, and macromolecular leveling agent into deionized water in proportion; S12, stirring to obtain a uniform auxiliary agent solution.

6. The method for preparing a solution for improving the activity of a supported catalyst according to claim 5, characterized in that: The step S12 specifically comprises stirring at room temperature for 2-3 hours to form a uniform solution.

7. A method for regenerating a catalyst, characterized in that: It includes the following steps: S21, add oxalic acid, ammonium metavanadate, and ammonium metatungstate to deionized water in sequence, and after they are completely dissolved, add 0.1-1% of the mixed auxiliary agent solution according to claim 6, and mix them evenly to obtain a final active solution; S22, placing the regenerated catalyst unit into an active solution mixed with an additive, ultrasonically immersing it, and then draining it; S23, placing the drained catalyst unit into calcination.

8. The regeneration method according to claim 7, characterized in that: The ultrasonic immersion time in step S22 is 10-15 minutes.

9. The regeneration method according to claim 7, characterized in that: The calcination temperature in step S23 is 350°C.

10. The regeneration method according to claim 9, characterized in that: The calcination time in step S23 is 3 hours.

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