Calcium Carbides

Description

Calcium carbide has the nominal formula of CaC₂ and the molecular weight of 64.0992 g/mol. The pure material is colorless, but most samples have a color ranging from black to grayish-white, depending on the grade. Its density is 2.22 g/cc and it melts at 2160°C with a boiling point (under an inert atmosphere) of 2300°C, where it decomposes. Its main use industrially is in the production of acetylene and calcium cyanamide, CaCN₂.

The Uses of Calcium Carbides

Calcium cyanamide is used as fertilizer.
in the “desulfurization” of iron (pig iron, cast iron and steel).
? as a fuel in steelmaking to extend the scrap ratio to liquid iron, depending on economics.
? as a powerful deoxidizer in steel at ladle treatment facilities.
? was used in carbide lamps, in which water drips on the carbide and the acetylene formed is ignited.
? in the ripening of fruit. Calcium carbide is used as source of acetylene gas, which is a ripening agent.
? in toy cannons where the acetylene is set off by an applied spark to create a loud “boom”.
? as floating, self-igniting naval flares for use as signals.

Preparation

Calcium carbide is produced industrially in an electric-arc furnace from a mixture of CaCO3 and coke (carbon) at approximately 2000°C.