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CN-121972158-A - Fiber ceramic-based catalytic filter element for industrial flue gas denitration and preparation method thereof

CN121972158ACN 121972158 ACN121972158 ACN 121972158ACN-121972158-A

Abstract

The invention discloses a fiber ceramic-based catalytic filter element for industrial flue gas denitration and a preparation method thereof, and belongs to the technical field of catalytic filter elements. The preparation method comprises the steps of firstly introducing a chelating agent into a preparation process of TiO 2 sol to improve the dispersibility and particle size uniformity of TiO 2 nano particles, effectively regulating the hydrolysis rate of butyl titanate by virtue of strong coordination force of the chelating agent and titanium ions to construct high-dispersion TiO 2 sol with small particle size, then immersing a fiber ceramic substrate into the TiO 2 sol, calcining to form a firm TiO 2 coating which is used as a carrier with high specific surface and enhances the binding force with the substrate, immersing a solution containing vanadium and tungsten precursors on a composite carrier, calcining to obtain a fiber ceramic-based catalytic filter element with good anti-blocking performance, water resistance, sulfur resistance and high temperature resistance, wherein main active components V 2 O 5 and a cocatalyst WO 3 are highly dispersed on the surface of the TiO 2 coating, and finally forming a selective catalytic reduction active site.

Inventors

  • PANG SHAOPENG
  • MIAO LINFENG
  • AN KANG
  • ZHANG JINYU
  • WANG XUETAO
  • XING LILI
  • ZHU JING
  • SUN RUIHAO

Assignees

  • 河南科技大学

Dates

Publication Date
20260505
Application Date
20260128

Claims (10)

  1. 1. The preparation method of the fiber ceramic-based catalytic filter element for industrial flue gas denitration is characterized by comprising the following steps of: (1) Adding butyl titanate into absolute ethyl alcohol to obtain a solution A, adding a chelating agent into absolute ethyl alcohol to obtain a solution B, and adding the solution B into the solution A under a stirring state to obtain TiO 2 sol, wherein the chelating agent is selected from acetylacetone or triethanolamine; (2) Impregnating a fiber ceramic substrate in the TiO 2 sol, and carrying out first vacuum impregnation, aging, first drying and first calcination to obtain a fiber ceramic substrate loaded with TiO 2 ; (3) Adding oxalic acid, ammonium tungstate and ammonium metavanadate into water, stirring to obtain an impregnating solution, placing the TiO 2 -loaded fiber ceramic substrate into the impregnating solution, and carrying out second vacuum impregnation, second drying and second calcination to obtain the fiber ceramic-based catalytic filter element for industrial flue gas denitration.
  2. 2. The method according to claim 1, wherein in the step (1), the molar ratio of the chelating agent to butyl titanate is (0.25-3): 1.
  3. 3. The method according to claim 2, wherein in the step (1), when the chelating agent is acetylacetone, the molar ratio of the chelating agent to butyl titanate is (1-3): 1, and when the chelating agent is triethanolamine, the molar ratio of the chelating agent to butyl titanate is (0.25-1.2): 1.
  4. 4. The method according to claim 1, wherein in the step (2), the mass ratio of the fibrous ceramic substrate to the TiO 2 sol is 1 (2-4).
  5. 5. The method according to claim 1, wherein in the step (2), the vacuum degree of the first vacuum impregnation is not less than 0.095MPa for 40 to 60 minutes; the aging temperature is 60-70 ℃ and the aging time is 10-12 hours; the temperature of the first drying is 105-120 ℃ and the time is 12-16h; The temperature of the first calcination is 400-450 ℃ and the time is 3-6h.
  6. 6. The method according to claim 1, wherein in the step (3), the concentration of oxalic acid in the impregnation liquid is 0.3 to 1.0wt%, the concentration of ammonium tungstate is 0.4 to 1.4wt%, and the concentration of ammonium metavanadate is 0.1 to 1.0wt%.
  7. 7. The method according to claim 1, wherein in the step (3), the mass ratio of the TiO 2 -loaded fibrous ceramic substrate to the impregnating solution is 1 (2-4).
  8. 8. The method according to claim 1, wherein in the step (3), the second vacuum impregnation is performed for 40-60min at a vacuum degree of 0.095MPa or more; the temperature of the second drying is 105 ℃ and the time is 12 hours; The temperature of the second calcination was 400 ℃ for 3 hours.
  9. 9. A fibrous ceramic-based catalytic filter element for industrial flue gas denitrification, characterized in that it is prepared according to the preparation method of any one of claims 1-8.
  10. 10. Use of a fibrous ceramic-based catalytic filter element for industrial flue gas denitrification according to claim 9 in industrial flue gas denitrification.

Description

Fiber ceramic-based catalytic filter element for industrial flue gas denitration and preparation method thereof Technical Field The invention belongs to the technical field of catalytic filter elements, and particularly relates to a fiber ceramic-based catalytic filter element for industrial flue gas denitration and a preparation method thereof. Background A large amount of nitrogen oxides (NO x) and Particulate Matters (PM) are discharged in the combustion process of fossil fuel and the incineration process of solid waste, and these pollutants not only cause a series of regional environmental problems such as photochemical smog, acid rain, haze and the like, but also threaten the respiratory system and cardiovascular health of human bodies. At present, a multistage purification unit serial process is generally adopted in industry to remove nitrogen oxides and particulate matters, namely, particulate matters are captured through dust removal equipment, and then a Selective Catalytic Reduction (SCR) device is utilized to remove NO x. However, the process has the problems of long flow, complex system, high initial investment, high operation and maintenance cost and the like. Under the background, a Catalytic Filter Element (CFE) with the functions of physical separation and catalytic conversion shows great application prospect. Currently, the mainstream technology of catalytic filter elements includes coated catalytic filter elements (e.g., SCR or oxidation catalyst supported on DPF, GPF) and monolithic catalytic filter elements (e.g., catalytic ceramic fiber filter elements). However, the prior art still has the remarkable problems that the bonding strength of the catalyst and the filtering matrix is insufficient, the catalyst is easy to fall off under high flow rate or thermal shock, the microporous structure is easy to be blocked by smoke dust, the pressure drop is increased, the energy consumption is increased, and meanwhile, the catalyst is easy to be deactivated due to high-temperature sintering or chemical poisoning under the complex working condition, so that the long-term stability and the conversion efficiency are influenced. Therefore, how to prepare a catalytic filter element with high bonding strength between the catalyst and the filter matrix, good anti-blocking performance, water resistance, sulfur resistance and high temperature resistance becomes a technical problem to be solved in the field. Disclosure of Invention In order to solve the technical problems, the invention provides a fiber ceramic-based catalytic filter element for industrial flue gas denitration and a preparation method thereof. In order to achieve the above purpose, the present invention provides the following technical solutions: The invention provides a preparation method of a fiber ceramic-based catalytic filter element for industrial flue gas denitration, which comprises the following steps: (1) Adding butyl titanate into absolute ethyl alcohol to obtain a solution A, adding a chelating agent into absolute ethyl alcohol to obtain a solution B, and adding the solution B into the solution A under a stirring state to obtain TiO 2 sol, wherein the chelating agent is selected from acetylacetone or triethanolamine; (2) Impregnating a fiber ceramic substrate in the TiO 2 sol, and carrying out first vacuum impregnation, aging, first drying and first calcination to obtain a fiber ceramic substrate loaded with TiO 2; (3) Adding oxalic acid, ammonium tungstate and ammonium metavanadate into water, stirring to obtain an impregnating solution, placing the TiO 2 -loaded fiber ceramic substrate into the impregnating solution, and carrying out second vacuum impregnation, second drying and second calcination to obtain the fiber ceramic-based catalytic filter element for industrial flue gas denitration. Further, in the step (1), the molar ratio of the chelating agent to the butyl titanate is (0.25-3): 1. Further, in the step (1), when the chelating agent is acetylacetone, the molar ratio of the chelating agent to butyl titanate is (1-3): 1, and when the chelating agent is triethanolamine, the molar ratio of the chelating agent to butyl titanate is (0.25-1.2): 1. Further, in the step (2), the mass ratio of the fiber ceramic substrate to the TiO 2 sol is 1 (2-4). Further, in the step (2), the vacuum degree of the first vacuum impregnation is more than or equal to 0.095MPa, and the time is 40-60min; the aging temperature is 60-70 ℃ and the aging time is 10-12 hours; the temperature of the first drying is 105-120 ℃ and the time is 12-16h; The temperature of the first calcination is 400-450 ℃ and the time is 3-6h. Further, in the step (3), the concentration of oxalic acid in the impregnating solution is 0.3-1.0wt%, the concentration of ammonium tungstate is 0.4-1.4wt%, and the concentration of ammonium metavanadate is 0.1-1.0wt%. Further, in the step (3), the mass ratio of the fiber ceramic substrate loaded with TiO 2 to the impregnating soluti