Aluminium phosphate

Aluminium phosphate

Aluminium phosphate
Aluminum phosphate
Other names
Aluminum phosphate
Aluminum monophosphate
Phosphoric acid, aluminum salt (1:1)
22784-12-9 (trihydrate)
ATC code A02
ChemSpider  Y
Jmol-3D images Image
RTECS number TB6450000
Molar mass 121.9529 g/mol
Appearance White, crystalline powder
Density 2.566 g/cm3, solid
Melting point 1,800 °C (3,270 °F; 2,070 K)
Boiling point Decomposes
Solubility Very slightly soluble in HCl and HNO3
1.546 [1]
R-phrases R36/37/38
S-phrases S26
NFPA 704
Lethal dose or concentration (LD, LC):
LD50 (Median dose)
4640 mg/kg (rat, oral)
> 4640 mg/kg (rabbit, dermal)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
 Y  (: Y/N?)

Aluminium phosphate (AlPO4) is a chemical compound. The anhydrous form is found in nature as the mineral berlinite. Many synthetic forms[2] of anhydrous aluminium phosphate are known. They have framework structures similar to zeolites and some are used as catalysts or molecular sieves. The dihydrate, AlPO4·2H2O is found as the minerals variscite and meta-variscite.[3][4] A synthetic hydrated form, AlPO4·1.5H2O is also known.[5] Commercially, an aluminium phosphate gel is available.


  • Aluminium phosphate (berlinite) 1
  • Aluminium phosphate dihydrate (variscite and meta-variscite) 2
  • Aluminophosphate molecular sieves 3
  • Uses of aluminium phosphate gel 4
  • Naturally occurring aluminium phosphate 5
  • References 6
  • External links 7

Aluminium phosphate (berlinite)

AlPO4 is isoelectronic with Si2O4, silicon dioxide. Berlinite looks like quartz and has a structure that is similar to quartz with silicon replaced by Al and P. The AlO4 and PO4 tetrahedra alternate. Like quartz, AlPO4 exhibits chirality[6] and piezoelectric properties.[7] Crystalline AlPO4 (berlinite) when heated, converts to tridymite and cristobalite forms, and this mirrors the behaviour of silicon dioxide.[8]

Aluminium phosphate dihydrate (variscite and meta-variscite)

The structure can be regarded as an assembly of phosphate anions, aluminium cations and water. The aluminium cations are six-coordinate.[4]

Aluminophosphate molecular sieves

There are many of aluminium phosphate


External links

  1. ^ Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw-Hill, 2002, ISBN 0-07-049439-8
  2. ^ a b Chemistry of Zeolites and Related Porous Materials: Synthesis and Structure Ruren Xu, Wenqin Pang, Jihong Yu, Qisheng Huo, Jiesheng Chen, John Wiley & Sons, 2007, ISBN 978-0-470-82233-3
  3. ^ Roncal-Herrero, T., Rodriguez-Blanco, J.D., Benning, L.G., Oelkers, E.H. (2009) Precipitation of Iron and Aluminum Phosphates Directly from Aqueous Solution as a Function of Temperature from 50 to 200°C. Crystal Growth & Design, 9, 5197-5205. doi: 10.1021/cg900654m.
  4. ^ a b Corbridge DEC 2013, Phosphorus: Chemistry, Biochemistry and Technology, 6th ed., CRC Press, Boca Raton, Florida, ISBN 978-1-4398-4088-7
  5. ^ Lagno, Felipe; Demopoulos, George P. (2005). "Synthesis of Hydrated Aluminum Phosphate, AlPO4·1.5H2O (AlPO4−H3), by Controlled Reactive Crystallization in Sulfate Media". Industrial & Engineering Chemistry Research 44 (21): 8033–8038.  
  6. ^ Tanaka, Yoshikazu; Kojima, Taro; Takata, Yasutaka; Chainani, Ashish; Lovesey, Stephen W.; Knight, Kevin S.; Takeuchi, Tomoyuki; Oura, Masaki; Senba, Yasunori; Ohashi, Haruhiko; Shin, Shik (2010). "Determination of structural chirality of berlinite and quartz using resonant x-ray diffraction with circularly polarized x-rays". Physical Review B 81 (14).  
  7. ^ Crystal growth of an α-quartz like piezoelectric material, berlinite, Motchany A. I.,Chvanski P. P., Annales de Chimie Science des Materiaux properties, 2001, 26, 199
  8. ^ a b c  
  9. ^ Wilson, Stephen T.; Lok, Brent M.; Messina, Celeste A.; Cannan, Thomas R.; Flanigen, Edith M. (1982). "Aluminophosphate molecular sieves: a new class of microporous crystalline inorganic solids". Journal of the American Chemical Society 104 (4): 1146–1147.  
  10. ^ Zeolites in Industrial Separation and Catalysis Santi Kulprathipanja, John Wiley & Sons, 26 Jan 2010
  11. ^ Zeolites and Catalysis, Jiri Cejka, Avelino Corma, Stacey Zones, John Wiley & Sons, 27 May 2010,ISBN 978-3-527-32514-6
  12. ^ Contemporary Drug Synthesis, Jie Jack Li, Douglas S. Johnson, Drago R. Sliskovic, Bruce D. Roth., John Wiley and Sons, 2004, ISBN 0471-21-480-9


In coastal areas of South Africa and Namibia, the combination of exceedingly old soils and a high input of phosphate from very fertile oceans due to the Benguela Current causes aluminium phosphate to accumulate to form a concentrated mineral known as aluminium phosphate rock. Only in recent years has there been any interest in the mining of these considerable deposits as a source of phosphorus for agriculture, but there could be considerable economic value if low-cost treatment becomes possible.

Although it is unstable to heat, in geologically stable regions like Australia and Southern Africa, aluminium phosphate is generally the most common form of phosphorus in soils, as it forms when phosphate in rainwater reacts with dissolved aluminium in the soil. Although it is not as insoluble as many other components of soils in those regions, aluminium phosphate can form exceedingly insoluble double salts known as taranakites with many essential elements for plant growth that are normally highly soluble in water, such as potassium and nitrogen.

Naturally occurring aluminium phosphate

In medicine an aluminium phosphate sol is used as adsorbent for toxoid and in the dried form, which contains hydrated AlPO4, as an antacid.[12] Industrially the Al-PO4-H2O system is used as the basis of many adhesives, binders and cements.[8]

Uses of aluminium phosphate gel

[11]) to direct the growth of the porous framework.[2]