Phosphoric Acid → Tricalcium Phosphate

Participants

Reaction Conditions

Reaction Steps

An aqueous solution of calcium dichloride was mixed with phosphoric acid of high fluorine content to produce a solution having a Ca/P mole ratio of 0.8 and a solution P/F ratio of about 20. The solution was treated with NaCl and chilled to produce a precipitate in accordance with the procedure of Example 1(a). The slurry was filtered yielding a filtrate having a Ca/P mole ratio of 0.8 and a P/F ratio of about 60. The solution was then fed to a conventional spray dryer at a rate of about 125 ml./min., with the exit gas temperature of the dryer being maintained at about 320°F. The dried product had a P/F ratio in excess of 100 and comprised a mixture of CaHPO4, CaClH2PO4.H2O, and Ca(H2PO4)2.

Provenance & Evidence