Sodium Hexametaphosphate

Sodium hexametaphosphate is a salt of composition Na₆[(PO₃)₆]. Sodium hexametaphosphate of commerce is typically a mixture of metaphosphates, of which the hexamer is one, and is usually the compound referred to by this name. Such a mixture is more correctly termed sodium polymetaphosphate.


Molar Weight611.77 g/mol
Melting Point628 °C
Boiling Point1,500 °C
Density2.484 g/cc
FormsWhite, Granules

Uses and Applications

Key applications

  • Buffer agent
  • Photographic supplies
  • Leather processing
  • Water treatment
  • Cleaning products
  • Oil and Gas
  • Pulp and paper
  • Textile handling
  • Detergent
  • Rubber


  • Rubber
  • Cleaning
  • Water Treatment
  • Pulp & Paper
  • Oil & Gas

Synonyms: Graham's Salt, Metaphosphoric Acid Sodium Salt, Polyphosphoric Acid Sodium Salt, SHMP, Sodium Hexametaphosphate, Sodium Hexametaphosphate Short Chain, Sodium Metaphosphate, Sodium Polyphosphate

Chemical Formula: CaH6Na4O18P6+6

CAS Number: 68915-31-1