Preparation method for catalyst for removing NOx

Abstract

The invention relates to a preparation method for catalyst for removing NOx, and belongs to the technical field of catalyst preparation. The preparation method comprises the following steps of: firstly, preparing a metal salt solution, then, enabling a carrier to stand in the salt solution to be dipped, taking out the carrier to be processed and dried, coating the carrier with molecular sieve material slurry which realizes a synergistic effect with the metal salt, drying and ageing the coated carrier, and finally, drying and roasting the carrier to obtain NOx catalyst. When the preparation method disclosed by the invention is adopted to prepare the catalyst for removing NOx, the preparation technology of the preparation method is simple and easy in operation, resources are saved, and the content of active ingredients can be more easily controlled.

Description

technical field

[0001] The invention relates to a method for preparing a catalyst for removing NOx, and belongs to the technical field of catalyst preparation. Background technique

[0002] Molecular sieve catalysts for NOx removal are currently a hot spot in research at home and abroad. Molecular sieves are widely considered to be excellent catalysts for NOx removal due to their wide catalytic window, high low-temperature activity, high thermal stability, strong acidity, and no secondary pollution. Characteristic, environmentally friendly new exhaust gas treatment catalyst material. Some countries and regions in Europe and the Americas have compulsorily adopted molecular sieves as catalysts for after-treatment of automobile exhaust.

[0003] The current process of molecular sieve SCR catalysts is to first introduce the active metal components into the pores of molecular sieves by means of wet exchange, and then make a slurry of metal-containing molecular sieves and coat th...

Examples

Embodiment 1

[0027] The cordierite carrier was placed in a 0.01 mol / L copper nitrate solution to stand still, and the amount of metal impregnated by the carrier was 1.5% of the dry weight of the subsequently coated molecular sieve. Then take it out and dry it at a drying temperature of 50°C for 2 hours. Then, the CHA molecular sieve slurry with adjusted configuration is coated on the dried carrier, and the coated carrier is kept at a drying rate of 0% for aging for 1 hour, and finally the drying and roasting temperature is 450 ° C. Time is 3h to get sample 1.

Embodiment 2

[0029] The aluminum titanate carrier was placed in a 0.5 mol / L copper acetate solution and allowed to stand still, and the amount of metal impregnated into the carrier was 2% of the dry weight of the subsequently coated molecular sieve. Then take it out and bake it at a drying temperature of 65°C for 1 hour. Then apply the adjusted CHA molecular sieve slurry on the dried carrier, keep the coated carrier at a drying rate of 25%, and age it for 4 hours, and finally dry and roast it at 500°C. Time is 2h to get sample 2.

Embodiment 3

[0031] The silicon carbide carrier was placed in a 1mol / L copper sulfate solution and allowed to stand, and the amount of metal impregnated by the carrier was 4% of the dry weight of the subsequently coated molecular sieve. Then take it out and dry it at a drying temperature of 80°C for 0.5h. Then apply the adjusted CHA molecular sieve slurry on the dried carrier, keep the coated carrier at a drying rate of 50%, and age it for 8 hours, and finally dry and roast it at 600°C. Sample 3 was obtained for 1 h.

technical field

[0001] The invention relates to a method for preparing a catalyst for removing NOx, and belongs to the technical field of catalyst preparation. Background technique

[0002] Molecular sieve catalysts for NOx removal are currently a hot spot in research at home and abroad. Molecular sieves are widely considered to be excellent catalysts for NOx removal due to their wide catalytic window, high low-temperature activity, high thermal stability, strong acidity, and no secondary pollution. Characteristic, environmentally friendly new exhaust gas treatment catalyst material. Some countries and regions in Europe and the Americas have compulsorily adopted molecular sieves as catalysts for after-treatment of automobile exhaust.

[0003] The current process of molecular sieve SCR catalysts is to first introduce the active metal components into the pores of molecular sieves by means of wet exchange, and then make a slurry of metal-containing molecular sieves and coat th...

Examples

Embodiment 1

[0027] The cordierite carrier was placed in a 0.01 mol / L copper nitrate solution to stand still, and the amount of metal impregnated by the carrier was 1.5% of the dry weight of the subsequently coated molecular sieve. Then take it out and dry it at a drying temperature of 50°C for 2 hours. Then, the CHA molecular sieve slurry with adjusted configuration is coated on the dried carrier, and the coated carrier is kept at a drying rate of 0% for aging for 1 hour, and finally the drying and roasting temperature is 450 ° C. Time is 3h to get sample 1.

Embodiment 2

[0029] The aluminum titanate carrier was placed in a 0.5 mol / L copper acetate solution and allowed to stand still, and the amount of metal impregnated into the carrier was 2% of the dry weight of the subsequently coated molecular sieve. Then take it out and bake it at a drying temperature of 65°C for 1 hour. Then apply the adjusted CHA molecular sieve slurry on the dried carrier, keep the coated carrier at a drying rate of 25%, and age it for 4 hours, and finally dry and roast it at 500°C. Time is 2h to get sample 2.

Embodiment 3

[0031] The silicon carbide carrier was placed in a 1mol / L copper sulfate solution and allowed to stand, and the amount of metal impregnated by the carrier was 4% of the dry weight of the subsequently coated molecular sieve. Then take it out and dry it at a drying temperature of 80°C for 0.5h. Then apply the adjusted CHA molecular sieve slurry on the dried carrier, keep the coated carrier at a drying rate of 50%, and age it for 8 hours, and finally dry and roast it at 600°C. Sample 3 was obtained for 1 h.

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