Calcium carbide synthesis.

Calcium carbide was synthetized for the first time by Friedrich Wöhler in 1836 mixing lime (CaO) and coke (C) in an electric arc furnace. Today the synthesis process is the same. CaO + 3 C → CaC₂ + CO . The main uses of calcium carbide are: production of acetylene when reacts with water; production of calcium cyanamide (fertilizer) and steelmaking (desulfurisation: to clean the sulphur from cast iron or pig iron). The industrial production began in 1895 and peaked in the 1960's. From then, the production of calcium carbide is declining, mainly because acetylene is produced from petrochemical sources, the use of other than oxi-acetylene welding techniques and the less use of calcium cyanamide.