Potassium Hydroxide

Potassium hydroxide is an inorganic compound with the formula KOH, and is commonly called caustic potash. It is used in various chemical, industrial, and manufacturing applications. Potassium Hydroxide is also a precursor to other potassium compounds. In food products, potassium hydroxide acts as a pH control agent, stabiliser, and food thickener. Potassium Hydroxide is available both in solid as liquid form

Synonyms
Caustic potash Lye, Potash lye, Potassia, Potassium hydrate, KOH
Chemical Formula
KOH
CAS Number
1310-58-3

Characteristics

Molar Weight
56,1056 g/mol
Melting Point
360 °C
Boiling Point
1,327 °C
Density
1.45
Forms
Liquid, Flakes, Pellets

Uses and Applications

Key applications

  • Metal working
  • Lawn and garden care
  • Fabric, textile and leather products
  • pH control
  • Laundry products
  • Lubricants
  • Household industrial
  • Cosmetic products
  • Soaps and detergents
  • Agricultural (non-pesticide)
  • Bleaching agent
  • Electronics

Industries

Potassium hydroxide

Potassium hydroxide is also known as caustic potash. Due to its high reactivity, it does not occur in its pure form in nature.
Potassium hydroxide is used in the food industry under the designation E 525. As a pH value regulator, it neutralises acids and creates alkaline conditions. Examples of applications include products containing cocoa, where alkalisation is desirable in order to improve the taste and solubility, as well as pretzels, for which a diluted potassium hydroxide solution or sodium hydroxide solution gives the characteristic brown crust and specific taste.
Potassium hydroxide is used in the pharmaceutical industry as a pH value regulator. A certain pH value is necessary to ensure the stability and effectiveness of pharmaceutical formulations such as eye and ear drops, injection solutions and creams.
Potassium hydroxide is also relevant for the production of pharmaceuticals, as it acts as a starting chemical for the production of esters and potassium salts, which are used as active ingredients or excipients in various medicines. KOH is also used in the production of medical soaps and antiseptic cleaning agents as well as in the treatment of warts and nail diseases.
Potassium hydroxide is used in the household and cleaning industry for the production of detergents, all-purpose cleaners, oven cleaners, bathroom cleaners and glass cleaners, among other things. It is used in drain cleaners to dissolve grease, hair build-up and organic blockages in pipes as it breaks down organic substances. It is also highly relevant for the production of liquid detergents and fabric softeners.
Potassium hydroxide is used in industrial and commercial cleaning agents to remove grease, oil and other organic contaminants from surfaces such as metal, plastic and glass. Examples of applications include the catering industry (kitchen appliances, extractor bonnets) and the automotive industry (engine cleaning).
Potassium hydroxide is used in agriculture as a raw material for the production of potassium-based fertilisers. It is also used to increase the pH value of acidic soils. Neutralising soil acidification improves the availability of nutrients and promotes plant growth.
Potassium hydroxide is also used in some plant protection products to combat certain pests and diseases. The substance is also used to clean agricultural machinery, equipment and stables.
Potassium hydroxide is used in the animal feed industry to adjust the pH value of animal feed. This is important to ensure stability and shelf life and to improve digestibility for animals.
It is also used as a source of potassium and improves the texture, solubility or miscibility of animal feed during processing. KOH is also used to clean and disinfect machines and equipment in animal feed production.
In the construction industry, potassium hydroxide is mainly used to produce potassium silicate, which is used as a binding agent in concrete, mortar and paints. It improves the strength, durability and water resistance of building materials. KOH is also used as a pH regulator and in the production of construction chemicals such as coatings and sealants.
In the paper industry, potassium hydroxide is required for the preparation of pulp and for regulating the pH value during the production process. It helps to remove impurities, soften the fibres and improve the quality of the end product. The substance is also used in the manufacture of speciality papers and coated products.
In water treatment, potassium hydroxide is used to regulate the pH value in order to neutralise acidity and create optimum conditions for chemical processes. It is also used to remove heavy metals, CO₂ and other impurities.
Potassium hydroxide plays a central role in various applications in the energy industry. It is used as an electrolyte in alkaline batteries such as nickel-cadmium and nickel-metal hydride batteries. In hydrogen production, KOH is used in electrolysis to efficiently split water into hydrogen and oxygen.
It is also used in fuel cells. In addition, potassium hydroxide acts as a catalyst in the production of biodiesel by transesterification of vegetable oils and is used in exhaust gas purification to absorb CO₂ and other acid gases in emission control systems.
In the lubricant industry, potassium hydroxide is mainly used to produce potassium soaps, which are used as thickeners in lubricating greases. Potassium soaps also give the lubricants high temperature resistance and water solubility, for example for use in industrial machining processes such as metalworking and as a coolant for machines.
In the polymer industry, potassium hydroxide is used as a catalyst and pH regulator in polymerisation processes. It supports the production of polyurethanes, epoxy resins and other special polymers by controlling chemical reactions and optimising material properties. The substance is also used in the synthesis of monomers and additives required in polymer processing.
In the rubber and caoutchouc industry, potassium hydroxide is primarily used as a catalyst and cleaning agent. It is used in the production of synthetic rubber by supporting polymerisation reactions and is used to remove impurities from latex or rubber materials.
KOH also helps to adjust the pH value during processing and in the production of chemicals that act as vulcanisation accelerators.
Potassium hydroxide is used in the textile industry to clean and pre-treat textile fibres. It is used to remove natural oils, fats and waxes from raw textiles, thus improving the fibres' absorption capacity for dyes and other chemical treatments.
Potassium hydroxide is also used to regulate the pH value in various textile processing operations. It is also used in the production of synthetic fibres and in the synthesis of certain dyes and printing chemicals. It supports the fixation of dyes on fibres.
KOH is also required in the synthesis of chemicals used as auxiliaries in textile processing, such as softeners and flame retardants. It is also used in the finishing of textiles to optimise fabric properties such as softness, smoothness and shine. Potassium hydroxide is also used in the production of biopolymers in textiles and in the recycling of used textiles.