Potassium Sulfamate

Formula: KSO3NH2 Potassium salt of sulfamic (amidosulfonic) acid. One of a few well crystallizing salts of this acid that crystallize well. Other salts often have excessive solubility.

Potassium Sulfamate


  • Crystal system: orthorombic
  • Crystal shape: flat tablets. Fast growing by cooling produces elongated crystals, slow evaporation gives shorter rectangular tables, resembling its aprent compound sulfamic acid.
  • Color: transparent, colorless.
  • Stability on air: stable on air


Reaction of sulfamic acid with potassium carbonate K2CO3 or hydroxide KOH:

K2CO3 + 2H3NSO3 → 2KSO3NH2 + H2O + CO2,

KOH + H3NSO3 → KSO3NH2 + H2O.


Solubility of this compound is big, and increases quickly with temperature. 100 ml of water dissolve 45.86 g of this salt at 9°C, 77.75 g at 25°C and 129.36 g at 45°C.

Crystals on the photo grew in one day from hot saturated solution after it was cooled to room temperature..

Slow growth using evaporation produces tabular crystals resembing those of sulfamic acid itself

Potassium sulfamate crystal grown using slow evaporation


The compound is generally safe.