i6 



NATURE 



[December 20, 19 17 



THE NITROGEN PROBLEM AND THE 



WORK OF THE NITROGEN PRODUCTS 



COMMITTEE.^ 



The Nitrogen Problem. 



''T^HE war has served to bring into special promin- 



^ ence the fundamental importance of nitrogen 

 compounds, not only for munitions, but also for agri- 

 culture. 



Nitrogen is an essential constituent of practically all 

 modern explosives, both of the so-called high-explosives 

 and of propellants. The manufacture of the vast quan- 

 tities that have been called for by the present condi- 

 tions of warfare has led to an unprecedented demand 

 for various nitrogen compounds. 



Nitrogen is also an essential constituent of all vege- 

 tation, and the world's production .of food is becoming 

 more and more dependent upon the utilisation of nitro- 

 genous fertilisers. The world's consumption of such 

 materials appears practically to double every ten years, 

 and in 19 13 had attained the large figure of 

 2,500,000 tons of Chile nitrate and about 1,400,000 tons 

 of ammonium sulphate. 



With the outbreak of war the demand for explosives 

 became of paramount importance, and the requirements 

 of agriculture for the time being took a secondary posi- 

 tion. The prospect of a world shortage of food, how- 

 ever, has served to bring the agricultural aspect of the 

 problem again into the forefront. In this connection it 

 is worthy of note that in 1898 Sir William Crookes, in 

 a carefully reasoned statement, directed attention to 

 the possibility of a shortage in the wheat supply of the 

 world and to the vital bearing upon this question of an 

 adequate supply of nitrogenous fertilisers. 



The researches of Sir William Crookes and the ex- 

 perimental work of Lord Rayleigh upon the fixation 

 of atmospheric nitrogen by means of the electric arc 

 pointed the way to a method of utilising the unlimited 

 supply of nitrogen in the air, and thus providing against 

 the time when other natural sources of nitrogen com- 

 pounds should have become exhausted. 



The establishment on a very large scale during the 

 past twenty years of processes for nitrogen fixation is 

 one of the most striking electro-chemical developments 

 of modern times. Special reference may be made to 

 the arc process as used in Norway, the Haber or 

 synthetic ammonia process developed in Germany, and 

 to the cyanamide process for the manufacture of nitro- 

 Hm from calcium carbide as carried on in Norway, 

 Sweden, France, Italy, Germany, and the United 

 States. 



In spite of the fact that the incentive to the com- 

 mercial establishment of nitrogen fixation may be said 

 to have originated in this country, no steps were taken 

 in the United Kingdom to obtain nitrogen compounds 

 other than cyanides synthetically. The ammonia re- 

 covered at gasworks and coke-ovens has constituted 

 practically the only form of combined nitrogen pro- 

 duced in this country During the war the command 

 of the seas has hitherto enabled Great Britain to rely 

 entirely upon importation for the whole of our sup- 

 plies of nitrate of soda, the most important raw mate- 

 rial of our explosives industry. The Central Powers, 

 on the contrary, having been cut off from external sup- 

 plies, were compelled to fall back upon their internal 

 resources, with the result that nitrogen fixation pro- 

 cesses, some of which were established commercially 

 before the war, have been developed upon an enormous 

 scale. 



Formation of the Nitrogen Products Committee. 

 Soon after the formation of the Munitions Inventions 

 Department in August, 1915, proposals for the fixation 



1 Abrideed from a Report orinted for the Munitions 

 ment by H.M. Stationery Office. 



NO. 2512, VOL. 100] 



Depart- 



of nitrogen began to be received from inventors. These 

 schemes were referred to the Chemical Inventions 

 Committee of the Advisory Panel, but as they were 

 isolated applications of the general problem and were 

 of limited scope, they did not immediately lead to any 

 definite line of policy being taken upon the question. 

 The importance of the problem was recognised, how- 

 ever, and the attention of the Minister was directed 

 to it from time to time in the monthly departmental 

 reports. 



The inauguration of the submarine campaign in 

 February, 1916, and the grave menace to overseas 

 supplies of nitrates emphasised the importance of 

 taking action on the matter. At this opportune 

 moment a memorandum on the nitrogen problem was 

 submitted to the Department by the Faraday Society. 

 Several conferences were held to discuss the steps that 

 should be taken, and as a result the Nitrogen Pro- 

 ducts Committee was constituted in the following June. 

 Members of the Advisory Panel, representatives of 

 other Departments of the Ministry of Munitions and 

 of the Government, and delegates of the leading scien- 

 tific societies were invited to serve. The terms of 

 reference to the Committee were as follows : — 



(i) To consider the relative advantages for this coun- 

 try and for the Empire of the various methods for the 

 fixation of atmospheric nitrogen from the point of view 

 of both war and peace purposes; to ascertain their 

 relative costs, and to advise on proposals relevant 

 thereto which may be submitted to the department. 



(2) To examine into the supply of the raw materials 

 required, e.g. pure nitrogen and hydrogen, and into the 

 utilisation of the by-products obtained. 

 . (3) Since some of the processes employed depend 

 for their success on the provision of large supplies of 

 cheap power, to ascertain where and how this can best 

 be obtained. 



(4) To consider w-hat steps can with advantage be 

 taken to conserve and increase the national resources 

 in nitrogen-bearing compounds and to limit their 

 wastage. 



(,£;) To carry out the experimental work necess'arv to 

 arrive at definite conclusions as to the practicability 

 and efficiency of such processes as mav apoear to the 

 Committee to be of value. 



(6) As a result of the foregoing steps, to advise as 

 to starting operations on an industrial" scale. 



Nitrogen Fixation Research. 



The necessity for research was evident from the out- 

 set, and the department at once took steps for the 

 organisation of a suitable research staff and the 

 acquisition of a laboratory. Fortunately, the co-opera- 

 tion of the authorities of University College was 

 secured, and a part of the new Ramsay Laborator} , 

 at that time scarcely completed, was placed at the 

 disposal of the department. 



The item placed first on the research programme 

 was a complete investigation into the production of 

 synthetic ammonia by the Haber process. This deci- 

 sion was influenced by the claims made for the process 

 and by the commanding position it occupies in Ger- 

 many, where the economic conditions as regards coal 

 supplies and the comparative absence of water-power 

 are similar to those in Great Britain. Moreover, the 

 almost complete lack of precise information concern- 

 ing the commercial details of this process made it 

 apparent that the research would present many un- 

 known factors, and was therefore likely to occiipv a 

 considerable time. 



Towards the end of the year the Committee came to 

 the conclusion that the ammonia oxidation process was 

 well adapted as an emergency measure for securing 

 quickly a considerable output of nitric acid or nitrates. 

 Although already working with more or less success 



