METHOD FOR PREPARING TRISODIUM PHOSPHATE DECAHYDRATE Russian patent published in 2006 - IPC C01B25/30 

FIELD: inorganic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for preparing trisubstituted sodium phosphate by neutralization of phosphoric acid to disodium phosphate and with sodium hydroxide to trisodium phosphate followed by isolation of trisodium phosphate crystals after cooling the neutralized solution. Method involves neutralization of disodium phosphate firstly with trisodium phosphate saturated solution at temperature 60-65°C up to the ratio Na₂O/P₂O₅ = 2.3-2.5 and then at temperature 70-80°C with sodium hydroxide solution at the rate 7-9 degrees/h to temperature 53°C. Using this method allows increasing the filtration rate of phosphate suspension and output of the process, respectively, by 1.2-1.4-fold, filtration output by 1.4-1.5-fold and enhancing the content of P₂O₅ in the end product up to 20.3-20.6 wt.-%.

EFFECT: improved preparing method.

1 tbl, 18 ex