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How is silicon carbide made from silica sand and coke?

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A periodic table element square for silicon shows atomic number 14, symbol Si, atomic weight range, electron configuration, and name. Icons indicate it is a solid nonmetal with diamond crystal structure and equal relative strength. Labels explain each property. — silicon Chemical properties of the element silicon.

Silicon carbide (SiC) is manufactured by heating a mixture of pure silica sand and finely ground coke in an electrical resistance-type furnace.1

The process involves the following steps:
* Preparation: The raw materials are arranged around a carbon conductor within the furnace.1
* Reaction: An electric current is passed through the conductor, generating temperatures between 2,200° and 2,700° C (4,000° to 4,900° F) in the core. This heat triggers a chemical reaction where the silicon in the sand and the carbon in the coke combine to form silicon carbide and carbon monoxide gas.1
* Processing: After a run lasting several days, the resulting core of SiC crystals is removed, crushed, ground, and screened into sizes suitable for industrial use.1

This method, which remains largely unchanged from the process developed by Edward G. Acheson in 1891, produces a material valued for its extreme hardness and thermal properties.12