- Calcium cyanamide is an inorganic compound with the chemical formula CaCN₂, consisting of calcium, carbon, and nitrogen. It is typically produced by reacting calcium carbide (CaC₂) with nitrogen gas at high temperatures in an electric furnace—a process known as the Frank–Caro process. The resulting product is a gray or black powder, often containing small amounts of calcium oxide and other impurities depending on its intended use.
- Calcium cyanamide is a versatile industrial chemical, primarily valued for its role as a nitrogen-rich fertilizer and as a precursor in various chemical manufacturing processes.
- In agriculture, calcium cyanamide functions as both a nitrogen fertilizer and a soil treatment agent. Once applied to moist soil, it hydrolyzes to form urea and ultimately releases ammonia and nitrate, which plants can absorb. Unlike other nitrogen fertilizers, calcium cyanamide also exhibits mild herbicidal, fungicidal, and pesticidal properties, helping control weeds, nematodes, and certain soil-borne pathogens. It improves soil health by reducing acidity and increasing calcium content, making it particularly beneficial in acidic or overworked soils. Because of its slow-release nitrogen properties, it minimizes nitrogen leaching and offers sustained plant nutrition.
- Beyond agriculture, calcium cyanamide serves as a valuable intermediate in the chemical industry. It is used in the synthesis of cyanamide (H₂NCN), dicyandiamide, thiourea, and various urea-based compounds. These are important for the manufacture of pharmaceuticals, resins, flame retardants, and water treatment chemicals. Additionally, it plays a role in metallurgy as a deoxidizer and desulfurizer in steel production, improving the quality and mechanical properties of the final alloy.
- Handling calcium cyanamide requires care, as it is alkaline and reactive with moisture, releasing ammonia and hydrogen cyanamide, both of which can be irritating or toxic in high concentrations. Prolonged exposure to the dust or fumes can cause skin, eye, or respiratory irritation, and thus it is typically handled with appropriate safety precautions in industrial settings.
