Pyrophosphoric acid
- CAS No.
- 2466-09-3
- Chemical Name:
- Pyrophosphoric acid
- Synonyms
- DIPHOSPHORIC ACID;eizh;iphosphoricaci;Pyrophosphorsure;PYROPHOSPHORIC ACID;inorganpyrophosphate;Diphosphoric(V) acid;Pyrophosphoric acid AR;PYROPHOSPHORIC ACID, 90+%;Pyrophosphoric acid (8CI)
- CBNumber:
- CB0740227
- Molecular Formula:
- H4O7P2
- Molecular Weight:
- 177.98
- MDL Number:
- MFCD00011343
- MOL File:
- 2466-09-3.mol
- MSDS File:
- SDS
- TDS File:
- TDS
| Melting point | 61 °C |
|---|---|
| Density | approximate 1.9g/ml (25℃) |
| storage temp. | -20°C, Hygroscopic |
| solubility | DMSO (Soluble) |
| pka | 0.99±0.10(Predicted) |
| form | white crystals |
| color | white crystals, crystalline |
| PH | pKa1= 0.86, pKa2 = 1.76, pKa3 = 5.88, pKa4 = 8.14(25℃) |
| Water Solubility | 709g/100mL H2O (23°C); soluble alcohol, ether [MER06] |
| Merck | 13,8098 |
| Stability | Hygroscopic, Moisture Sensitive |
| InChI | InChI=1S/H4O7P2/c1-8(2,3)7-9(4,5)6/h(H2,1,2,3)(H2,4,5,6) |
| InChIKey | XPPKVPWEQAFLFU-UHFFFAOYSA-N |
| SMILES | P(OP(O)(=O)O)(O)(O)=O |
| CAS DataBase Reference | 2466-09-3(CAS DataBase Reference) |
| EWG's Food Scores | 1 |
| FDA UNII | 4E862E7GRQ |
| EPA Substance Registry System | Diphosphoric acid (2466-09-3) |
| UNSPSC Code | 12352106 |
| NACRES | NA.21 |
SAFETY
Risk and Safety Statements
| Symbol(GHS) |   GHS05,GHS07 |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Signal word | Danger | |||||||||
| Hazard statements | H302-H314 | |||||||||
| Precautionary statements | P280-P305+P351+P338-P310 | |||||||||
| Hazard Codes | C | |||||||||
| Risk Statements | 22-34 | |||||||||
| Safety Statements | 26-36/37/39-45 | |||||||||
| RIDADR | UN 3260 8/PG 2 | |||||||||
| WGK Germany | 3 | |||||||||
| RTECS | JL6672500 | |||||||||
| F | 3-9-21 | |||||||||
| HazardClass | 8 | |||||||||
| PackingGroup | III | |||||||||
| HS Code | 28092000 | |||||||||
| Storage Class | 8B - Non-combustible corrosive hazardous materials | |||||||||
| Hazard Classifications | Acute Tox. 4 Oral Skin Corr. 1B |
|||||||||
| NFPA 704 |
|
Pyrophosphoric acid price More Price(8)
| Manufacturer | Product number | Product description | CAS number | Packaging | Price | Updated | Buy |
|---|---|---|---|---|---|---|---|
| Sigma-Aldrich | 433314 | Pyrophosphoric acid technical grade | 2466-09-3 | 100g | $92 | 2026-04-30 | Buy |
| Usbiological | 166092 | Pyrophosphoric Acid | 2466-09-3 | 5g | $403 | 2026-06-03 | Buy |
| Chem-Impex | 36643 | Pyrophosphoric acid ≥94%(Assaybytitration) | 2466-09-3 | 100G | $95.8 | 2026-05-19 | Buy |
| TRC | P997700 | Pyrophosphoric acid | 2466-09-3 | 5g | $120 | 2021-12-16 | Buy |
| Medical Isotopes, Inc. | 72225 | Pyrophosphoric acid | 2466-09-3 | 5G | $610 | 2021-12-16 | Buy |
Pyrophosphoric acid Chemical Properties,Uses,Production
Preparation
Pyrophosphoric acid may be prepared by heating orthophosphoric acid at 215°C:
2H3PO4 → H4P2O7 + H2O
The acid solution in pure form can be obtained by ion exchange, passing an aqueous solution of sodium pyrophosphate, Na4P2O7, through a suitable cation exchange column.
Reactions
The acid has four replacable H+ ions. Its dissociation constants indicate that two H+ ions are strongly acidic while the other two protons are weakly acidic. The first dissociation constant especially is very large:
H4P2O7 + H2O ↔ H3O+ + H3P2O7¯ Ka1 ~ 10–1
H3P2O7¯+ H2O ↔ H3O+ + H2P2O72– Ka2 ~ 1.5x10–2
PHOSPHORIC ACID, PYRO 701H2P2O72¯ + H2O ↔ H3O+ + HP2O73– Ka3 ~ 2.7x10–7
HP2O73¯ + H2O ↔ H3O+ + P2O74¯ Ka4 ~ 2.4x10–10
Pyrophosphoric acid forms acid salts, such as NaH3P2O7 and Na2H2P2O7.
Description
Pyrophosphoric acid, also known under the name
diphosphoric acid, is colorless, odorless, hygroscopic
and is soluble in water, diethyl ether and ethyl alcohol.
It is produced from phosphoric acid by dehydration.
Pyrophosphoric acid slowly hydrolyzes in the presence
of water into phosphoric acid.
H4P2O7 +H2O2H3PO4
Upon heating, phosphoric acid loses water, being
converted successively, and to some extent concurrently,
into the pyro- and meta-acids:
2H3PO4H4P2O7 +H2O
nH3PO4(HPO3)n + [H2O]n
Chemical Properties
White to very pale yellow glassy solid
Physical properties
Colorless needles or liquid; hygroscopic. Crystallizes in two anhydrous forms: a metastable form melting at 54.3°C and a second and more stable form melting at 71.5°C; extremely soluble in cold water, reacting very slowly to form phosphoric acid; decomposing much faster in hot water; very soluble in alcohol and ether.
Uses
Pyrophosphoric Acid has been shown to enhance the rate of pyrophosphate hydrolysis by nonenzymatic catlysis and by inorganic pyrophoshatase. Pyrophosphoric Acid can be used for the preparation of vanadyl pyrophosphato methoxide cluster anion. Pyrophosphoric Acid is used in anion binding of inorganic phosphates due to is ability to form complexes.
Uses
Catalyst, manufacture of organic phosphate esters, metal treatment, stabilizer for organic per- oxides.
Preparation
According to early investigators, the pyro-acid is
formed as low as 100 °C, and the conversion is complete
between 255 and 260 °C. Phosphorous oxychloride
reacts with phosphoric acid in the following manner:
5H3PO4 + POC133H4P2O7 + 3HC1
A mixture of the ortho- and meta-acids may be
condensed together to form the pyro-acid by heating on the water bath:
nH3PO4 +[HPO3]n[H4P2O7]n
Definition
ChEBI: An acyclic phosphorus acid anhydride obtained by condensation of two molecules of phosphoric acid.
Pyrophosphoric acid Preparation Products And Raw materials
Raw materials
Preparation Products
| Supplier | Tel | Country | ProdList | Advantage | |
|---|---|---|---|---|---|
| Shanghai Guanghua Technology Co., Ltd | 13801626616 | chemol@126.com | China | 305 | 58 |
| Wuhan beileye Biomedical Technology Co., Ltd | 15871353653 18086118076 | 1784708432@qq.com | China | 4746 | 58 |
| Hubei Qifei Pharmaceutical Chemical Co., Ltd | 027-59322506 18071128681 | 1438082200@qq.com | China | 9554 | 58 |
| Hubei Shiteng Chemical Technology Co. LTD | 19086915685 18971850150 | 1273131441@qq.com | China | 4993 | 58 |
| Chengdu Huachun Technology Co., Ltd | 400-1166-196 15982826727 | cdhxsj@163.com | China | 14571 | 60 |
| Shanghai Hanyang Chemical Products Co., Ltd | 13356258271 | 3961848022@qq.com | China | 112 | 58 |
| Shandong Yuxuan Chemical Products Co., Ltd | 15315790065 15315790065 | 1748782088@qq.com | China | 104 | 58 |
| J & K SCIENTIFIC LTD. | 18210857532 18210857532 | jkinfo@jkchemical.com | China | 96815 | 76 |
| Meryer (Shanghai) Chemical Technology Co., Ltd. | 4006356688 18621169109 | market03@meryer.com | China | 40202 | 62 |
| Beijing HwrkChemical Technology Co., Ltd | 89508211 18501085097 | sales.bj@hwrkchemical.com | China | 9407 | 55 |
View Lastest Price from Pyrophosphoric acid manufacturers
| Image | Update time | Product | Price | Min. Order | Purity | Supply Ability | Manufacturer | |
|---|---|---|---|---|---|---|---|---|
 |
2026-09-11 | Pyrophosphoric acid
2466-09-3
|
1KG | 98%min | 30tons/month | WUHAN FORTUNA CHEMICAL CO., LTD | ||
 |
2026-09-02 | Pyrophosphoric acid
2466-09-3
|
$1.00-8.00 | 1kg | 99% | Henan Fengda Chemical Co., Ltd | ||
 |
2025-06-27 | Pyrophosphoric acid
2466-09-3
|
$10.00-30.00 | 50KG | 99% | 500000kg | Hebei Chuanghai Biotechnology Co., Ltd |
-
- Pyrophosphoric acid
2466-09-3
- $0.00
- 98%min
- WUHAN FORTUNA CHEMICAL CO., LTD
-
- Pyrophosphoric acid
2466-09-3
- $1.00-8.00
- 99%
- Henan Fengda Chemical Co., Ltd
-
- Pyrophosphoric acid
2466-09-3
- $10.00-30.00
- 99%
- Hebei Chuanghai Biotechnology Co., Ltd
