CATALYST FOR SELECTIVE CLEANING OF GASES FROM NITROGEN OXIDES AND METHOD OF ITS USE Russian patent published in 2025 - IPC B01J23/22 B01J21/04 B01J23/34 B01J21/06 B01J35/00 B01J35/69 B01J35/63 B01J35/36 B01J35/61 B01J37/02 B01J37/04 B01D53/56 

FIELD: chemistry.

SUBSTANCE: invention relates to catalysts for neutralizing industrial gases from nitrogen oxides by selective catalytic reduction with ammonia in the presence of oxygen. Disclosed invention solves the problem of developing a highly active catalyst which is effective in a wide range of temperatures and volumetric flow rates, as well as a method of using it. Described is a catalyst for cleaning exhaust gases from nitrogen oxides by selective catalytic reduction with ammonia in oxidative conditions, which contains aluminium and vanadium oxides, containing V₂O₅ in amount of 5-14 wt.%, at least one compound of an element from the group: manganese, silicon, calcium in amount of 0.1-10 wt.% in terms of oxide, titanium in amount of 0.1-65 wt.% in terms of oxide, Al₂O₃ – the rest. Total pore volume in catalyst is 0.35-0.65 cm³/g, the porous structure has a bimodal pore size distribution with two maxima, the first maximum in the pore diameter range of 2-50 nm, the second maximum in the pore diameter range of 100-2,500 nm, wherein volume of pores with diameter of more than 100 nm is not less than 20% in total specific volume of pores, BET specific surface is 110-300 m²/g, mechanical abrasion strength is not less than 94%. Also described is a method of cleaning exhaust gases from nitrogen oxides in a process of selective catalytic reduction with ammonia in the presence of oxygen using the disclosed catalyst, which is carried out at temperatures of 220-360 °C, volumetric flow rates of 7,000-25,000 h^-1, ratio NH₃/NO_x=1.1-1.25 and volume fraction of NO_x at reactor inlet 0.05-0.16 vol.%.

EFFECT: invention enables to obtain a catalyst which is resistant to deactivation in gas streams containing sulphur compounds and/or water vapour, and also enables to select optimum hydrodynamic operating conditions of industrial reactors.

5 cl, 8 ex, 3 tbl