Potassium Tetraborate

Potassium Tetraborate is a product resulting from the controlled reaction of potassium hydroxide, water and boric acid.
Request a sample.

Applications & Benefits

Technical Granular
Technical Powder

Buffering Agent
When dissolved in water, potassium tetraborate hydrolyzes to give a mildly alkaline solution. It is thus capable of neutralizing acids. It also combines with strong alkalis to lower their pH. The pH of a 2% (wt.) solution of potassium tetraborate is 9.2. The value increases very slightly with increasing concentration, and diminishes very slightly with increasing temperature. The relatively constant
pH of potassium tetraborate solutions makes them excellent buffering agents, and these are often recommended as primary standards in analytical procedures.

Welding/soldering/brazing fluxes
Potassium tetraborate is an excellent solvent for metallic oxides at high temperatures. In the field of metallurgy, it is used in the preparation of special welding, soldering and brazing fluxes of stainless steel or various non-ferrous metals to avoid the “glare” associated with sodium borate.

Lubricating oil additives
Potassium borates dispersed in a very finely divided state, improve the load-carrying, anticorrosion, and antiwear properties of industrial and automotive gear lubricants. Under extreme conditions, potassium borates interact with metal load-bearing surfaces to form a film of extraordinary resilience. This tenacious film provides outstanding load-carrying capacity and wear protection. Diazotype developer A light-sensitive composition can be produced by combining a nonionic aromatic diazo compound and a cationic dye-borate anion complex. Potassium tetraborate can be used as the source of borate anion.

Being a good absorber of thermal neutrons, potassium tetraborate is used for emergency shutdowns in nuclear-powered ships.


Senior Development Specialist

Fred Ascherl

Fred has worked for Rio Tinto Borates for over 37 years. He currently holds a position as a Senior Development Specialist.