IQ2 TRANSACTIONS OF WAGNER 



CATALYSIS IN THE INORGANIC FIELD 



This is accomplished by passing a proper mixture of air and ammonia 

 rapidly through a plug of smooth platinum coated with spongy platinum. The 

 proper temperature for the catalysis is obtained by heating the gases before 

 entry at the expense of the gases issuing from the region of catalysis. Other 

 catalysts for this process are known, but platinum has been most used. This 

 process makes the production of nitric acid directly dependent upon the pro- 

 duction of ammonia. As sources of ammonia we have the gas and coke plants, 

 in which coal is destructively distilled; the later processes in which nitrogen 

 from the air is made to combine with elements to form, for example, nitrids, 

 or with compounds to form, for example, cyanamids, from which ammonia is 

 directly obtainable; and lastly, the direct union of nitrogen from the air with 

 hydrogen. 



This last-mentioned process involves the use of pure iron as a catalyst, 

 judging from the data obtainable; but other metals have also been found to 

 have more or less catalytic action under similar conditions. A highly de- 

 veloped form of special apparatus is required (shown and explained by lantern- 

 slide) in which the gaseous mixture or the separate gases may be raised to 650°- 

 700° C. while under 200 atmospheres pressure. The "poisons" to the catalyst 

 in this process are numerous and difficult to remove. (See page 12.) 



The disadvantages of the high cost of electric current, the unfortunate 

 location of our best hydroelectric plants, the difficulties of highly developed 

 forms of special apparatus, the ready poisoning of most catalysts, the necessity 

 for highly purified gases — all these and other disadvantages have been over- 

 come in a method for the fixation of atmospheric nitrogen now (March) current 

 in our chemical journals. I refer to Bucher's process, in which air is passed 

 over heated coal or coke previously mixed with an alkali, and with finely 

 divided iron which acts as the catalyst. An alkah cyanid results. The 

 catalyst operates at a moderate temperature, 9oo°-95o°, and could be installed 

 in an emergency almost anywhere. The process means something more than 

 a mere addition to our fighting power, for it can serve to increase our agri- 

 cultural resources enormously. The sodium cyanid produced, if soda is the 

 alkali used, is readily convertible into ammonia and sodium formate : 



NaCN -f- 2H2O -^ HCOaNa -\- NH3. 



If the cyanid is kept just above its melting point and a current of air 

 passed through it, it burns to sodium cyanate: 



NaCN -1- -> NaCNO. 



