Calcium carbide cyanamide

Aero Calcium Carbide. [Cyanamid Canada] Calcium carbide. 

At about the same time that the Birkeland-Eyde process was developed, the Frank-Caro cyanamide process was commercialized (14). In this process limestone is heated to produce lime, which then reacts with carbon in a highly energy-demanding reaction to give calcium carbide. Reaction with N2 gives calcium cyanamide [150-62-7] which hydrolyzes to ammonia and calcium carbonate (see Cyanamides). 

Calcium carbide is also used to produce calcium cyanamide [156-62-7] CaCN2, (see Cyanamudes). 

In the United States calcium carbide-based acetylene is mainly used in the oxyacetylene welding market although some continues to be used for production of such chemicals as vinyl ethers and acetylenic alcohols. Calcium carbide is used extensively as a desulfurizing reagent in steel and ductile iron production allowing steel mills to use high sulfur coke without the penalty of excessive sulfur in the resultant steel (see Sulfurremoval and recovery). Calcium cyanamide production continues in Canada and Europe (see Cyanamides). 

Reaction With Nitrogen. Calcium cyanamide is produced from calcium carbide... 

The largest use for calcium carbide is in the production of acetylene for oxyacetylene welding and cutting. Companies producing compressed acetylene gas are located neat user plants to minimize freight costs on the gas cylinders. Some acetylene from carbide continues to compete with acetylene from petrochemical sources on a small scale. In Canada and other countries the production of calcium cyanamide from calcium carbide continues. More recentiy calcium carbide has found increased use as a desulfurizing reagent of blast-furnace metal for the production of steel and low sulfur nodular cast iron. 

For the manufacture of calcium cyanamide, cmde calcium carbide (ca 3.36 x 1.68 mm or 6 x 12 mesh) can be used, whereas for cyanamide and dicyandiamide, a 74 p.m (200 mesh) anhydrous carbide is used. 

The filtered cake produced from the manufacture of dicyandiamide contains about 86% calcium carbonate. American Cyanamid Co. blends the dried waste for the manufacture of calcium carbide-based desulfurized reagents as a gas releasiag agent. 

Of the four steps described above, only the first two consume large amounts of energy, especially the calcium carbide step. With increasing energy costs, attention should be focused on alternatives for making calcium cyanamide. 

Calcium cyanamide hy action of atmospheric nitrogen on calcium carbide... 

Acetylene and ethylene compete as a chemical raw material. Ethylene is generally more economical, resulting in declining use of acetylene as a raw material. Calcium carbide, a raw material for acetylene has other uses. Treated with nitrogen, it gives calcium cyanamide, valuable as a fertilizer and weed killer, and a raw material for the production of melamine, used ir ng some modern plastics. 

Accidents occur with calcium cyanamide, which are due to the presence of 2% of calcium carbide. 

Absorption of water dining handling or storage of technical calcium cyanamide may cause explosions, owing to liberation of acetylene from the calcium carbide content (up to 2%). Precautions are discussed. 

Frank-Caro Also called the Cyanamide process. An early process for fixing atmospheric nitrogen. Lime and carbon were heated to produce calcium carbide this was reacted with nitrogen to give calcium cyanamide, which was hydrolyzed with steam to yield ammonia and calcium carbonate. Developed by A. Frank and N. Caro from 1895 at Dynamit, Germany, and used in Germany, Norway, and Italy until it was replaced by the Haber-Bosch process after World War I. 

Aluminum phosphide Amyl trichlorosilane Benzoyl chloride Boron tribromide Boron trifluoride Boron trifluoride etherate Bromine pentafluoride Bromine trifluoride n-Butyl isocyanate Butyllithium Butyric anhydride Calcium Calcium carbide Chlorine trifluoride Chloro silanes Chlorosulfonic acid Chromium oxychloride Cyanamide Decaborane Diborane... 

Polzeniusz-Krauss A process for making calcium cyanamide from calcium carbide by heating it in a nitrogen atmosphere in a chaimel kiln ... 

The most important apphcation of calcium carbide is the production of acetylene. It also is used to produce calcium cyanamide, CaCNs, a nitrogen fertilizer and a source of ammonia. 

Calcium cyanamide is prepared from calcium carbide. The carbide powder is heated at about 1,000°C in an electric furnace into which nitrogen is passed for several hours. The product is cooled to ambient temperatures and any unreacted carbide is leached out cautiously with water. 

Nitrogen reacts with calcium carbide at high temperature to form calcium cyanamide ... 

Commerdal calcium cyanamide (nitrolime), containing carbon and small quantities of calcium carbide, is suitable for this preparation. 

Calcium Cyanamide. ]CAS 156-62-7). CaCN-. white solid, funned (11 by heating cyanamide or urea with calcium oxide, sublimes at 1.05(1 C. (2) by heating calcium carbide at 1.100-I.200 C in a current of nitrogen. Decomposes in water with evolution of NFL. 

The cyanamide process has made cyanamide and its derivatives more easily available for commercial synthesis. Coke and limestone are heated together in the electric furnace for the production of calcium carbide. This substance, along with a small amount of calcium chloride which acts as a catalyst, is then heated at 800-1000° in a stream of nitrogen gas. 

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