Molochite is a man-made, pure-white, granular material produced from the calcination of kaolin. Its high refractoriness is harnessed in foundry, refractory and ceramic applications.
Molochite is an alumino-silicate produced by the calcination of specially selected kaolins. It is a pure-white granular material created by firing low-iron content kaolin to very high temperatures (about 1,500°C) to transform the kaolin crystals into a mixture of crystalline mullite and amorphous silica glass with no crystalline silica (cristobalite free).
Molochite is characterized by its rough surface, very high mechanical stability, resistance to thermal shock and very low thermal expansion making it a material of choice for high temperature industries such as foundry investment casting, refractories and ceramics as kiln-furniture.
Imerys produces high-quality molochite from primary kaolins mined and processed at its extensive deposit in Cornwall, southwest England. The deposit is renowned for its fine-quality reserves with a low-iron, low–alkali and high alumina content.
Further upstream, our Technology Center based in Villach Austria features an extensive range of minerals processing, testing and analysis tools focused on high resistance materials.
In foundry investment casting, Imerys molochite is an excellent refractory material for the production of shell molds using wax. Successive coats of increasingly coarse molochite slurry are applied onto wax models. The rough surfaces of the molochite confer excellent mechanical properties to the ceramic shell and its low thermal expansion guarantees the dimensional accuracy of the finished parts. It is also an excellent filler for foundry coatings in iron, steel and aluminium castings.
In ceramics production, molochite is the prefered calcined clay component of kiln furniture bodies due to its low level of contraction during firing which confers unparalleled shape stability to the parts at high temperatures. It is widely used as a filler for controlling the physical and chemical properties of porcelain bodies, glazes and engobes.
In refractory production, molochite is the ideal choice for some applications where linear change is a concern with strong thermal shock resistance. Due to its composition it can be used at high temperature (too alkalies content). Coke oven application is one well-known area of use.
Our extensive assets turn unprocessed raw materials into value-added products and solutions such as molochite.