METHOD OF PURIFICATION OF THE EXTRACTING PHOSPHORIC ACID Russian patent published in 2008 - IPC C01B25/46 C01B25/18 C01B25/234 

FIELD: chemical industry; food-processing industry; other industries; production of the heat-resistant alloys on the basis of the nickel.

SUBSTANCE: the invention is pertaining to the method of purification of the extracting phosphoric acid (EPA) with production of the product having the low content of the impurities, which may be used in production of the phosphorus salts of technical and alimentary qualification. The method of purification of the extracting phosphoric acid provides for extraction of the phosphoric acid by the tributyl phosphate with the withdrawal of the raffinate, water flushing of the extract with withdrawal of the water flushing solution and the flushed extract, the water reextraction pf the phosphoric acid from the flushed extract with obtaining of the productional acid, which are exercised by commixing of the water and organic phases with formation of the emulsion in the mode of pulsation. The water flushing of the extract is conducted by means of dispergation of the water in the organic phase at the consumption of the dispergated water of 0.04-0.25 t per 1 t of Р₂О₅ in the original extract and intensity of the pulsation equal to 1200-3000 mm/minute. The flushing solution is routed for extraction, where it is either admixed with the extracting phosphoric acid before treatment with the extragent, or it is introduced directly into the mixture of the acid and the extragent containing in the aqueous phase , 35-42 % of Р₂О₅. The water flushing of the extract is conducted in 1-4 stages. The method ensures the substantial improvement of the water flushing column performance standards, reduction of the losses of the expensive extragent and the metal consumption of the production process, stabilization of the process of the water flushing of the extract, and also the increased outlet of the productional extracting phosphoric acid.

EFFECT: the invention ensures the substantial improvement of the water flushing column performance standards, reduction of the expensive extragent losses and the metal consumption, stabilization of the process of the water flushing of the extract, the increased outlet of the productional extracting phosphoric acid.

3 cl, 1 tbl, 5 ex