Reaction #1960513

ord-0810dc3a27a3407f940df4a5e2501b51

Reaction equation

O=[N+]([O-])[O-].O=[N+]([O-])[O-].[Ca+2]
calcium nitrate salt
O.O.O=P([O-])([O-])[O-].[Ca+2].[Ca+2]
dicalcium phosphate dihydrate
C1=CC2C(C1)[C@@H]1C=C[C@H]2C1
DCPD
O=P([O-])([O-])OP(=O)([O-])[O-].[Ca+2].[Ca+2]
calcium pyrophosphate
C1=CC2C(C1)[C@@H]1C=C[C@H]2C1
DCPD
→
O=P([O-])([O-])[O-].O=P([O-])([O-])[O-].[Ca+2].[Ca+2].[Ca+2]
Calcium Phosphate

Reactants

O=[N+]([O-])[O-].O=[N+]([O-])[O-].[Ca+2]
calcium nitrate salt
O.O.O=P([O-])([O-])[O-].[Ca+2].[Ca+2]
dicalcium phosphate dihydrate
C1=CC2C(C1)[C@@H]1C=C[C@H]2C1
DCPD
—
CaHPO4.2H2O
O=P([O-])([O-])OP(=O)([O-])[O-].[Ca+2].[Ca+2]
calcium pyrophosphate
C1=CC2C(C1)[C@@H]1C=C[C@H]2C1
DCPD

Reagents

O=P([O-])([O-])O.O=P([O-])([O-])O.O=P([O-])([O-])[O-].O=P([O-])([O-])[O-].O=P([O-])([O-])[O-].O=P([O-])([O-])[O-].O=P([O-])([O-])[O-].O=P([O-])([O-])[O-].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Fe+2].[Mg+2]
whitlockite

Conditions

Temperature
500°CELSIUS
Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    Otheras precipitated material (no agitation
  2. 2
    TemperatureWarming of the sample to >25° C.
  3. 3
    Otheran exothermic reaction
  4. 4
    Otherresulting in the formation of a white, pasty solid
  5. 5
    TemperatureHeat treatment and X-ray diffraction of this solid

Procedure

Example 1 was repeated with the addition of 10.00 g dicalcium phosphate dihydrate, DCPD, CaHPO4.2H2O (Aldrich Chemical Co., Inc. #30, 765-3, CAS #7789-77-7) to the homogeneous solution following endothermic dissolution of the calcium nitrate salt. The DCPD was present both as suspended solids and as precipitated material (no agitation used). Warming of the sample to >25° C. initiated an exothermic reaction as described in Example 1, resulting in the formation of a white, pasty solid. Heat treatment and X-ray diffraction of this solid were conducted as described in Example 1. Following heat treatment in air at 500° C. for 1 hour, XRD indicated the solid to be composed of whitlockite as the primary phase along with calcium pyrophosphate (Ca2P2O7) as the secondary phase.

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US08303976B2uspto-grants-2012_11