It is known that the chemical industry makes a significant contribution to the progress of the development of our country. The most serious environmental problem of the industry is the emission of exhaust gases containing toxic substances, including nitrogen oxides. The maximum allowable average daily content of nitrogen oxides in terms of N₂O₅ in the atmospheric air of populated areas should not exceed 0.1 mg/m³ while meeting the requirement for a one-time maximum content of nitrogen oxides not more than 0.3 mg/m³. In the production of nitric acid, the main problem is the emission of nitrous gases and the development of methods to reduce their emission. There are various ways to neutralize nitrous gases: purification of gases from nitrogen oxides in an equal-flow hollow tower; purification of gases from nitrogen oxides in combined type apparatuses; purification of gases from weakly oxidized nitrogen oxides, absorption of nitrogen oxide by ammonium sulfite solutions; oxidation and absorption of nitrogen oxides by aqueous solutions of oxidizers; purification of gases from nitrogen oxides with aqueous solutions of hydrogen peroxide; absorption of slightly oxidized nitrogen oxides by aqueous solutions of potassium permanganate; absorption of highly oxidized nitrogen oxides; studies of the absorption of nitrogen oxides by organic sorbents; adsorption of nitrogen oxides by solid sorbents; purification of gases from nitrogen oxides and other impurities with peat-alkaline sorbents to obtain peat-nitrogen fertilizers; absorption of nitric oxide by solutions of ferrous sulphate [1].