Phosphorus oxide (P4O10) → Phosphorus oxide (P4O10)

HRID 848437Notes

Reaction equation

HRID 848437 reaction equation
[O:1]=[P:2]12[O:13][P:11]3([O:14][P:4]([O:6][P:7]([O:10]3)([O:9]1)=[O:8])(=[O:5])[O:3]2)=[O:12]>O.[Fe]>[P:2](=[O:1])([OH:13])([OH:9])[OH:3].[O:5]=[P:4]12[O:3][P:2]3([O:9][P:7]([O:10][P:11]([O:13]3)([O:14]1)=[O:12])(=[O:8])[O:6]2)=[O:1]

Participants

5

Reactant 1

HCID 14812Phosphorus oxide (P4O10)

Product 2

HCID 1004Phosphoric AcidHCID 14812Phosphorus oxide (P4O10)Yield 72.5%

Reagents, catalysts & solvents 2

HCID 23925IronCatalystHCID 962WaterSolvent

Procedure

A wet process acid of concentration and impurity content as in Ex. 6-9 has heated in a single cell as described above to 500° C. to give a suspension of concentrated acid of 82% P2O5, 2020 ppm Fe and 710 ppm Al, which was diluted with water and hydrolysed, then filtered to give a clear phosphoric acid of 72.5% P2O5 (of which 12% is poly P2O5). 55 parts of this acid were mixed with 37 parts of recycled third mother liquor and 8 parts of melted third crop of crystals (see below) and the mixture (containing 73.4% P2O5, 2005 ppm Fe and 710 ppm Al) was crystallized at 25° C. with seed crystals of anhydrous ortho phosphoric acid to give 50 parts of first crystals of anhydrous ortho acid and 50 parts of first mother liquor. The first mother liquor was crystallized at 20° C. for 30 minutes to give 20 parts of a second crop of crystals and 30 parts of a second mother liquor. The first crystals and second crop of crystals were combined, melted and crystallized at 25° C. for 10 minutes to give 33 parts of product crystalline anhydrous ortho acid (with 150 ppm Fe, 75 ppm Al) which was separated from 37 parts of mother liquor, the third mother liquor which was recycled to the initial crystallization. The second mother liquor was crystallized at 16° C. for 75 minutes to give 8 parts of a third crop of crystals which were recycled after melting into the initial crystallization and 22 parts of a fourth mother liquor which was recycled to the evaporator feed acid. Thus overall 55 parts of the filtered diluted acid from the evaporator were obtained 33 parts of twice crystallized acid.

Workup

  1. concentrationA wet process acid of concentration and impurity content as in Ex
  2. temperature6-9 has heated in a single cell
  3. customas described above to 500° C.
  4. customto give
  5. filtrationhydrolysed, then filtered

Sources & evidence

ORD record
ord-4b2a3d3bcf9040bc907290310a941e73
Source dataset
uspto-grants-1981_10
Patent number
US04296082

Reaction notes

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