What are the applications of potassium hydroxide and where can you buy it?

KOH, i.e. caustic potash: properties

In the scientific nomenclature, the inorganic compound KOH – potassium hydroxide is also called caustic potash (or corrosive potash) and its aqueous solution is named potash lye. It is an extremely corrosive and hygroscopic strong alkaline in the form of white crystals or flakes.

KOH dissolves in water, melts at 360°C and boils at 1320°C. How is it produced? It is possible to obtain a potassium hydroxide solution through electrolysis of a potassium chloride solution. Bear in mind that the substance is highly toxic and causes irritation of skin and the mucous membranes of the eyes and nose. If swallowed, even small amounts of KOH lead to acute poisoning and are even life-threatening!

Industrial uses of potassium hydroxide

Due to its caustic, bleaching and drying properties, potassium hydroxide is widely used in the chemical (production of detergents), automotive, pharmaceutical, food and beauty industries.

What is it used for? The white crystals of KOH are used for example in the industrial production of:

• soaps (mostly soft soap), detergents, washing liquids and bleaches,
• alkaline batteries, nickel-cadmium accumulators (potassium hydroxide is the electrolyte),
• bio-fuels,
• dyes,
• medical products,
• impregnants used for the preservation and hydrophobisation of sandstone, granite, limestone, travertine and paving block,
• laboratory reagents (gynaecological tests and diagnostics),
• silicon photovoltaic cells (potassium hydroxide is used in the process of texturing, i.e. smoothing silicon wafers).

In the food industry, potassium hydroxide granules are used as an acidity regulator and stabiliser designated as E525. It is added to a variety of processed products such as confectionery, preserves, cocoa or dietary supplements.

The majority of properties that characterise potassium hydroxide are also typical for caustic soda lye, a compound which bears a very close resemblance to potassium hydroxide. That chemical substance is also used in the production of soaps or drain cleaners due to their shared hygroscopic properties. Check out the product range offered by the PCC Group for a high quality soda lye. You can also get PCC Greenline® soda lye, which has been developed in line with green chemistry.

Other, non-standard uses of KOH

Scientists keep discovering new possible uses of potassium hydroxide in different industries, or even the funeral industry! The solution of KOH is used for what is known as resomation, i.e. biocremation, where the water in the body undergoes gradual combustion. The decomposition is slow and no harmful compounds enter the atmosphere.

As a highly corrosive substance, potassium hydroxide is also used in engraving and a graphic technique of lithography. KOH facilitates the fast and precise surface processing of the lithographic plate.

Potassium hydroxide: where can you buy a high-quality product?

At present, anybody can buy potassium hydroxide. The product is available from online stores and dedicated industry-specific physical stores. Bear in mind that professional industrial applications require a certified product with an appropriate specification only. So where should you procure large quantities of KOH? Instead of looking for bargains on the Internet, it is advisable to contact directly a manufacturer.

How much does potassium hydroxide cost? The price depends on the grade, quality, intended use and packaging size. Different vendors and producers offer pharmaceutical, cosmetic, chemical, technical and food-grate KOH which comes as granules, flakes or ready-made solutions. The cheapest packages of potassium hydroxide marketed in Poland (for preparing lab reagents) cost below twenty PLN. Producers provide individual pricing for large quantities of KOH.