| abstract |
The invention relates to a method for producing sodium tripolyphosphate used in the manufacture of food products, detergents, bleaching agents and reagents for reducing water hardness. The purpose of the invention is to reduce arsenic and lead impurities by increasing the efficiency of the filtration process. A method of producing sodium tripolyphosphate, which includes neutralizing phosphoric acid with soda, forming a precipitate and deactivating the filtered solution, dehydrating and calcining phosphates, in which the neutralization step is carried out to a ratio of NaaO: PaOs equal to (0.8-1.07):; 1, while the introduction of a neutralized solution of sodium sulfide B in an amount of 3-6 kg per 1000 kg of sodium tripolyphosphate. Table 2. (l with |