The chemical compound potassium hydroxide, (KOH) sometimes known as caustic potash, potassa, potash lye and potassium hydrate, is a metallic base. It is a very alkaline compound used in agriculture to correct the pH of acidic soils. It can also be used as a fungicide or even an herbicide.

Uses

It is a major industrial chemical used as a base in a wide variety of chemical processes.

It is used as a catalyst in reactions like the production of biodiesel, the advantage of using KOH and not NaOH is that NaOH "clumps" and KOH doesn't.

Some uses of KOH include acrylate ester copolymer coating, defoaming agents used in the manufacture of paper, formulation aid for food, pH control agent, polyethylene resins, textile processing.

Food uses include washing or chemical peeling of fruits and vegetables, chocolate and cocoa processing, caramel color production, poultry scalding, and forming a skin on pretzels before baking, olive aging, soft drink processing, ice cream thickener.

Other uses include in veterinary medicine in disbudding calves horns and to dissolve scales and hair; manufacture of cleansers; in wart removal and as a cuticle solvent. This type of compound is also used in washing powders, some denture cleaners, non-phosphate detergents, and drain or pipe cleaners.

It is also a traditional ingredient in the making of soap, and for this purpose was historically obtained in an impure form by steeping wood ash in water for a long period.