KOHrasvaus

KOHrasvaus is a chemical process used in soap production in which fats or oils (triglycerides) are hydrolyzed by potassium hydroxide (KOH). In Finnish terminology, KOHrasvaus refers specifically to saponification with potassium hydroxide, yielding potassium soaps rather than the sodium soaps produced by NaOH. The process also releases glycerol as a byproduct.

The chemical reaction commonly described is triglyceride plus three molecules of potassium hydroxide to form glycerol and three molecules of potassium fatty acid salts, known as potassium soaps. Potassium soaps are typically softer and more water-soluble than their sodium analogues, which makes them favorable for liquid soaps, cream soaps, and certain detergents. Factors that influence the process include the quality of the fats, the concentration of alkali, temperature, and reaction time.

Applications of KOHrasvaus include industrial soap manufacturing and consumer cleaning products. Potassium soaps are valued for their softness, moisturizing properties, and performance in low- to medium-viscosity formulations. They are commonly used where a flexible, easy-to-dispense soap is desirable and where the formulation benefits from a more soluble, milder soap.

Safety and handling considerations are important, as potassium hydroxide is caustic and reacts exothermically with water. Proper protective equipment, ventilation, and waste neutralization are required, along with adherence to local regulations for alkaline chemical handling and disposal.

See also: Saponification, Potassium hydroxide, Soapmaking, Fatty acids.