Tricalcium Phosphate → Calcium bis(metaphosphate)

HRID 1732816Notes

Reaction equation

HRID 1732816 reaction equation
[P:1]([O-])([O-:4])([O-:3])=[O:2].[Ca+2:6].[P:7]([O-])([O-:10])([O-:9])=[O:8].[Ca+2].[Ca+2]>[NH4+]>[O-:4][P:1](=[O:3])=[O:2].[O-:10][P:7](=[O:9])=[O:8].[Ca+2:6]

Participants

3

Procedure

A fertilizer rich in calcium metaphosphate is produced by reacting phosphorite or other calcium phosphate-bearing mineral, with ammonium bisulphate to produce a precipitate of calcium sulphate and an aqueous solution rich in ammonium mono- and biphosphates. The latter is then heated in a furnace in the presence of further calcium phosphate-bearing mineral, to produce calcium metaphosphate. The calcium sulphate can be converted to calcium carbonate by reaction with ammonium carbonate, to produce ammonium sulphate. The ammonium sulphate can be heated with the furnace gases from the production of calcium metaphosphate, to produce the required ammonium bisulphate for reaction with phosphorite and the required ammonium carbonate for a conversion of the calcium sulphate to calcium carbonate.

Sources & evidence

ORD record
ord-6967bf5f26284ee39c94a8c0446596b8
Source dataset
uspto-grants-1980_12
Patent number
US04239523

Reaction notes

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