FIXED jSTITEOGEX RESEARCH LABORATORY. 639 



electric discharges are continuing, for there is reason to believe that 

 very fundamental improvements may be achieved through such 



studies. 



CYANIDE PROCESS. 



As previously mentioned, the cyanide process of nitrogen fixation 

 has not been successfully developed on a commercial scale. The 

 forrn of the process deA'eloped in this country consists essentially of 

 heating a mixture of soda ash, carbon, and iron to an elevated tem- 

 perature in the presence of nitrogen gas. The product is a crude 

 cyanide containing 5 to 10 per cent nitrogen which can either be 

 treated to produce a marketable form of cyanide or subjected to the 

 action of steam to produce ammonia. Several important advantages 

 are clairned for the process and much experimental work has been 

 done on it in this countr3^ During the war the Government built a 

 plant for the production of cyanide at Saltville, Va., which was 

 designed to have a capacity of 10 tons of cyanide per day. Although 

 some cyanide was produced, it was shown during the short period 

 of operation that both the chemical and engineering features of the 

 jDrocess required further study and development. 



The laborator}' has made a general survey of this process, the re- 

 sults of which are published in the report on the fixation and utiliza- 

 tion of nitrogen. It became evident that two types of research were 

 necessary to its further development — research Avhich would afford 

 a more accurate knowledge of the fundamental reactions involved 

 in sodium cyanide formation, and research on the engineering fea- 

 tures of the process, particularly the development of a satisfactory 

 method of manipulating the charge under treatment. The labora- 

 tory has been conducting research of the first type. A study was 

 undertaken to determine the influence of such factors as quality and 

 proportions of materials, temperature and duration of treatment, 

 purity of nitrogen, and p)resence of iron, on the completentss and 

 rate of cyanide formation. The results already obtained indicate 

 that failure to obtain satisfactory conversion to cyanide in the semi- 

 commercial tests which have be'- n made in the past was due in part 

 to the low qualit}^ of carbon and iron used. Information on the 

 mechanism of the reaction has also been obtained, which suggests 

 ways of improving the process. The work on this jjroc ss is con- 

 tinuing. 



There is some doubt as to whether the cyanide process can be so 

 developed that fertilizer can be produced as cheaply by it as by other 

 processes. It should be pointed out, however, that th? development 

 of a process for the production of cyanide, as a final product, directly 

 from atmospheric nitrogen, is very important in view of the in- 

 creasing demand for nitrogen in the form of cyanides. Until 

 recently their large-scale commercial use was confined ess ntially 

 to the hydrometallurgy of gold and silver ores, with smaller quanti- 

 ties consumed in caseharclening and electroplating, but in recent 

 years the application of hydrocyanic acid as a fumigating agent for 

 fruit trees has opened a new and rapidly growing market of par- 

 ticular interest to this department. 



