Quick Answer
Lye and potassium hydroxide (KOH) are often used interchangeably, but technically, "lye" usually refers to sodium hydroxide (NaOH), while potassium hydroxide is a distinct chemical compound with its own properties.
What is Lye and What is Potassium Hydroxide?
Lye, also known as sodium hydroxide, is a caustic substance used in various applications, including soap making. It’s available in different concentrations, typically ranging from 10% to 30% sodium hydroxide solution. When it comes to soap making, the most common concentration is 30% NaOH, which is suitable for most recipes.
Key Differences and Usage
Potassium hydroxide (KOH), on the other hand, is often used for making soap with a higher pH level, which results in a milder and more moisturizing soap. KOH is typically used in concentrations between 10% to 20%. The main distinction between lye (NaOH) and potassium hydroxide (KOH) lies in their different chemical properties, which affect the final product’s pH and lather characteristics.
Soap Making Considerations
When making soap with either NaOH or KOH, it’s essential to follow safety guidelines, including wearing protective gear and handling the substances in a well-ventilated area. For beginners, working with sodium hydroxide is usually recommended due to its wider availability and familiarity. However, potassium hydroxide can be a better option for those looking to create a milder soap with a higher pH level.
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