Potassium Chloride

The chemical compound potassium chloride (KCl) is a metal halide salt composed of potassium and chlorine. In its pure state, it is odorless and has a white crystal appearance


KCl is added to cement slurries for application in water-sensitive shales and clays. By preventing clay swelling, it helps improve the cement/formation bond. For these applications, KCl is effective at temperatures between 50°F and 380°F (10°X and 193°C). Typical KCl concentrations are 2 to 5% by weight of water (BWOW). KCl slightly decreases the effectiveness of fluid-loss additives and dispersants, and it slightly accelerates cement slurries.


The benefits of using KCl include:

  • Helps control clay swelling in the presence of water and helps minimize fines migration.
  • Helps promote a better bond between the cement and the formation.
  • Slightly accelerates slurry setting time.

Potassium chloride was historically known as " Muriate of potash". This name is occasionally still encountered in association with its use as a fertilizer.

Potash varies in color from pink or red to white depending on the mining and recovery process used.


White potash, sometimes referred to as soluble potash, is usually higher in analysis and is used primarily for making liquid starter fertilizers. KCl is used in medicine, scientific applications, and food processing. It occurs naturally as the mineral sylvite and in combination with sodium chloride as sylvite