Sodium Hydroxide, Lye and Potassium Hydroxide (Koh)

Two commonly used solvents in soap making are known as Caustic Soda (Sodium Hydroxide or Lye) and Potassium Hydroxide (Potash or KOH). It is important to understand the difference between the two products in order to choose the product that is most suitable for your needs. Both products are a white powder/flake form, strong alkaline, and corrosive. 

Caustic Soda vs. Potassium Hydroxide

When it comes to choosing between the two, our customers find that lye is great for solid soap whereas the potash is better for creating liquid soap. This is largely due to the saponification reaction that occurs.