METHOD OF PRODUCING PHOSPHORIC ACID Russian patent published in 2016 - IPC C01B25/20 

FIELD: chemistry.

SUBSTANCE: invention relates to technology of inorganic substances, in particular, to methods of producing phosphoric acid, and can be used for recycling contaminated white phosphorus. Method involves oxidation of sludge of contaminated white phosphorus with oxygen and hydrating obtained phosphorus pentoxide. Process is carried out in a vessel inside an autoclave. White phosphorus is placed in vessel and water is poured. Then air is fed at pressure 0.3 mPa and 0.6 mPa. Dissolved oxygen reacts with contaminated sludge-containing white phosphorus to form P₂O₅. Phosphorus pentoxide is then hydrated to form phosphoric acid. Sludge is accumulated in inner reservoir. Method enables to regulate kinetics of chemical reaction and concentration of obtained phosphoric acid via air pressure variation in reaction system. Conducting process according to disclosed method enables to obtain phosphoric acid of required concentration in one unit at normal temperature and relatively low pressure.

EFFECT: completely avoiding emission of phosphorus oxide into atmosphere.

1 cl, 1 dwg, 2 ex