Superphosphoric acid is made by
the concentration of regular wet-process acid up to P2O5
concentrations of 78%. Granular polyphosphates suitable
for bulk blending are made by reacting ammonia with
regular wet process acid of 52% P2O5 content and using the
heat of reaction to drive off water to produce a phosphate
melt of 10-43-0, with about 40% of the phosphorus in the
polyphosphate form. These materials are, however, not
suitable for bulk blending due to their “sticky” nature (10).
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Viscous, water-white liquid. Water solu-
ble. Does not crystallize on standing; hygroscopic.
The commercial acid is a mixture of orthophos-
phoric acid with pyrophosphoric, triphosphoric, and
higher acids and is sold on the basis of its calcu-
lated content of H3PO4, e.g., 115%. Superphospho-
ric acid is a similar mixture sold at 105% H3PO4.
These acids revert slowly to orthophosphoric acid
on dilution with water.
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Polyphosphoric Acid is a ligand used as an analytical tool to image nanoparticles through photon emission topography. Used also in the synthesis of pharmaceuticals.
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ChEBI: A polymerized phosphorus oxoacid of general formula HO[PO2OH]nH formed by condensation of orthophosphoric acid molecules and containing a backbone chain consisting of alternating P and O atoms covalent
y bonded together.
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Polyphosphoric acid (PPA) is widely employed as acylation and alkylation reagent in various reactions. It is a strong mineral acid with excellent dehydrating properties.
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Toxic by ingestion; strong irritant.
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Polyphosphoric acid is obtained by heating the wetprocess
phosphoric acid. It contains around 72%
phosphorus (as P2O5) and represents a series of
phosphoric acids containing more than one atom of
phosphorus (such as H4P2O7). The general formula is
Hn+2PnO3n+1.
Solubility in water
Polyphosphoric acids are miscible with water, hydrolyzing to orthophosphoric acid with the generation of heat. They are insoluble in hydrocarbons and halogenated hydrocarbons.
