METHOD OF PREPARING NITRIC ACID Russian patent published in 2003 - IPC

FIELD: inorganic chemistry, chemical technology. SUBSTANCE: invention relates to the field of technology of preparing non-concentrated nitric acid. Method of preparing nitric acid involves stages of ammonia oxidation, preparing and processing nitrous gas, among them, absorption. Preparing and processing nitrous gas is carried out using additional oxidation of nitrogen oxide (II) to nitrogen oxide (IV) with nitric acid solution of intermediate concentration with simultaneous enrichment of nitrous gas with nitrogen oxide (IV) at definite temperature up to evolving reaction moisture from nitrous gas being the absorption process is carried out in the presence of solution of desorbed and deoxidized nitric acid. Method allows to use low-potential energy of nitrous gas effectively, enhance nitric oxide content in nitrous gas before absorbing column, improve economy the process in the general improvement and retaining basic technological indices of process in the known level. Invention can be used in production of concentrated nitric acid, nitrite/nitrate salts and potassium fertilizers. EFFECT: improved method of preparing. 3 cl, 1 dwg, 1 ex