Phosphinic Acid → Tricalcium Phosphate

An aqueous solution of 8.06 g 50 wt % H3PO2 reagent was combined with 6.00 g distilled water to form a clear, colorless solution in a 250 ml Pyrex beaker on a hotplate/stirrer. To this solution was added 19.23 g Ca(NO3)2.4H2O. The molar ratio of Ca/phosphate in this sample was 4/3 and the equivalent solids [as octacalcium phosphate, Ca8H2(PO4)6-5H2O] was 30.0 wt %. Endothermic dissolution of the calcium nitrate tetrahydrate proceeded under ambient conditions, eventually forming a homogeneous solution once the sample warmed to room temperature. Warming of the solution above 25° C. initiated a vigorous exothermic reaction as described in Example 1. After approximately three minutes, the reaction was essentially complete leaving a moist, white, pasty solid.

1. distillationdistilled water
2. customto form a clear, colorless solution in a 250 ml Pyrex beaker on a hotplate/stirrer
3. customeventually forming a homogeneous solution once the sample
4. temperatureWarming of the solution above 25° C.
5. customa vigorous exothermic reaction
6. customthe reaction was essentially complete leaving a moist, white, pasty solid

ORD record

ord-b68aee8a73e046da915acf25d5b8813f

Source dataset

uspto-grants-2001_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06325987B1