Frank-Caro calcium cyanamide process

To make calcium cyanamide, atmospheric nitrogen can be fixed by the Frank-Caro or Cyanamide process. This process is based on the fact that metallic carbides, particularly calcium carbide, readily react with nitrogen to form the metal cyanamide. In the first step of this process lime and carbon are heated to produce calcium carbide. Then fairly pure nitrogen reacts with the calcium carbide to form calcium cyanamide ... 

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). 

First industrial process involving atmospheric N2 — the Frank-Caro process for calcium cyanamide. 

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. 

In the Frank Caro process, invented in 1895 - 7 and known as the "calcium cyanamide method," a carbide, such as Ca carbide absorbs nitrogen to form cyanamideffertilizer), which by a further treatment may be transformed either into cyanide or into ammonia. Thi s process was used in Europe, USA and Canada (Refs 38 71). In the Serpek process introduced in France and not adopted in the USA, nitrogen was "fixed" as Al nitride and this gave ammonia when treated with steam(Refs 38 and 71) In the Bagnulo process, invented in Italy, ammonia and other N-contg substances... 

More promising around 1900, however, was the fixation of atmospheric nitrogen by calcium carbide to afford cyanamide, the process of Nikodemus Caro and Adolph Frank, particularly after Caro found that cyanamide applied to the soil reacted with water to give off ammonia. This also relied on electricity, particularly inexpensive... 

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