Preparing method and product of hydrophobic sulfur-resistant low-temperature denitration catalyst

Abstract

The invention relates to a preparing method and product of a hydrophobic sulfur-resistant low-temperature denitration catalyst, and belongs to the technical field of denitration catalysts. In the method, by adding a hydrophobic modifier, introducing hydrophobic groups into the catalyst and changing the hydrophobicity of the surface of the catalyst, the vapor in smoke can be less adsorbed to the surface of the catalyst in the use process, and the competitive adsorption between the vapor and NH3 is reduced; in addition, with a TiO2-SiO2 compound as the carrier, the SO2 oxidization rate can be reduced, the deposition of ammonium sulfate salt on the surface of the catalyst or in pores is reduced, the denitration rate of the catalyst can be ensured, and the service life of the catalyst can be prolonged. In addition, a template agent is added in the preparing process, mesopores of the catalyst are increased, the specific surface area and pore volume of the catalyst are improved, the catalystcan contain more ammonium sulfate salt, the toxin inactivation rate of the ammonium sulfate salt is reduced, and the catalyst can be better applied industrially. The catalyst is simple in preparing process, not high in device requirement and suitable for industrial production.

Description

technical field [0001] The invention belongs to the technical field of denitration catalysts, and in particular relates to a preparation method and a product of a hydrophobic sulfur-resistant low-temperature denitration catalyst. Background technique [0002] Nitrogen oxides are one of the main pollutants that pollute the atmospheric environment. Thermal power plants, automobile exhaust and industrial kilns (boilers) are the main sources of nitrogen oxide emissions, of which industrial kilns (boilers) account for 38% of the total nitrogen oxide emissions, and thermal power plant flue gas and automobiles The nitrogen oxides in the tail gas have been basically controlled, but the smoke emitted by industrial kilns (boilers) (such as: industrial boilers, glass ceramic furnaces, cement furnaces, iron and steel metallurgical sintering furnaces, cracking equipment in coking and petrochemical systems, etc.) The concentration of nitrogen oxides in the air is higher than the emission...

AI Technical Summary

Problems solved by technology

Because the flue gas emission temperature of industrial kilns (boilers) is mostly in the range of 170°C to 300°C, while the current mainstream SCR denitrification catalysts in thermal power plants work at temperatures of 305°C to 420°C, power plant denitrification catalysts cannot meet the requirements of industrial kilns (boilers). Furnace denitrification purification requirements

However, the main problem faced by the existing low-temperature denitration catalysts is the poisoning and deactivation of ammonium sulfate or ammonium bisulfate, and the denitration rate drops significantly.

Catalyst deactivation due to ammonium sulfate or ammonium bisulfate poisoning is due to NH in flue gas at low temperature 3 、H 2 O, SO 2 It is easy to form ammonium sulfate or ammonium bisulfate when adsorbed on the surface of the catalyst, but the temperature of the flue gas is too low to reach the decomposition temperature of ammonium sulfate or ammonium bisulfate in the pores of the catalyst (above 300°C). A lot of ammonium sulfate or ammonium bisulfate will accumulate on the surface, so that the denitrification rate of the catalyst will drop sharply, leading to catalyst deactivation

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