METHOD OF MAKING HIGH PURITY CALCIUM HYDROGEN PHOSPHATE DIHYDRATE

摘要

The method for producing a high purity dicalcium phosphate (CaHPO4 2H2O) is characterized by overflow-reacting a mixture of calcium chloride as a byproduct in the ammonia-soda process and phosphoric acid with a mixted gas of ammonia (A) and air (B) [mixing ratio of (A):(B) is 1:0.55-1.65 . In the reaction, the pH of the first, the second and the third reactor is each 0.5-1.8, 2.4-4.5 and 5.0- 6.5. The produced CaHPO4 2H2O is used as an abrasive agent for a toothpaste.