HYDROXYLAMINE SULFATE PREPARATION PROCESS Russian patent published in 2005 - IPC

FIELD: industrial inorganic synthesis.

SUBSTANCE: invention relates to preparation of hydroxylamine sulfate used in caprolactam production. Process consists in the steam-oxygen conversion of ammonia, stabilization of resulting nitrose gas by hydrogenation of excess oxygen, two-step condensation of steam in the nitrose gas concentration process, liquid-phase hydrogenation of nitric acid condensate from the second-step nitrose gas concentration process to produce pure nitrogen monoxide (mixed then with main nitrose gas stream) and hydrogenated condensate with platinum dissolved therein, after which follows direct hydroxylamine sulfate synthesis in 19% sulfuric acid medium. To produce 19% sulfuric acid, concentrated sulfuric acid is subjected to two-step dilution: it is first mixed with condensate from the second-step nitrose gas concentration process and desalted water to 21.1-22.3% concentration and purified on activated carbon in presence of oxygen and then mixed with product of hydrogenation of the second-step condensate hydrogenation process to obtain 19% acid used in the hydroxylamine sulfate synthesis stage. As a result, platinum dissolved in the second-step condensate hydrogenation process is precipitates in reductive medium on the hydroxylamine sulfate synthesis platinum catalyst and recycled into the process thereby providing wasteless technology.

EFFECT: considerably reduced process losses.

2 dwg