THE NITROGEN OF PROCESSED FERTILIZERS. 23 



decompose through natural conditions, be they in the soil or out of it, 

 a certain amount of hydrolysis of the proteins takes place and if the 

 decomposition is allowed to proceed long enough under proper condi- 

 tions complete hydrolysis will result. 



The principle involved in making the nitrogenous material in the 

 soil available and in increasing the availability of low-grade nitrog- 

 enous materials by factory treatment is therefore the same. In other 

 words, the general chemical principle to be applied in making avail- 

 able the nitrogen of low-grade fertilizers, trade wastes, etc., is that of 

 complete or partial hydrolysis by any suitable means of the proteins 

 contained in the wastes. Partial hydrolysis of proteins may be accom- 

 plished by means of heat, boiling, steaming, heating under pressure, 

 and both partial and complete hydrolysis may be obtained by treating 

 with strong acids or alkalis, either in the cold for a long time or heating 

 to a high temperature, the extent of hydrolysis depending on the sev- 

 eral conditions. In a number of processes already in use various of 

 these treatments are practiced, resulting in different degrees of hydrol- 

 ysis of the original proteins. While the availability of the nitrogen 

 of a fertilizer depends on the substances in which the nitrogen is con- 

 tained, it also depends on the extent of hydrolysis of the proteins used in 

 the manufacture. It may be stated that in general the more extended 

 and final the hydrolysis the more available the nitrogen of the com- 

 pounds formed, since as has been shown, the final products of hydroly- 

 sis are utilized by the plant as such and are at the same time more 

 readily changed into ammonia by bacteria, etc., than are the interme- 

 diate compounds produced by partial hydrolysis. 



SUMMARY. 



The base goods used as a type of processed fertilizers is an organic 

 nitrogenous fertilizer which contains acid phosphate. This product 

 is produced by the action of sulphuric acid on certain trade wastes; 

 the heat is generated by the interaction of the acid with the organic 

 wastes and rock phosphate in the course of the manufacture of acid 

 phosphate. It is here shown that the hydrolysis of the protein is 

 almost complete, the nitrogenous compounds in the finished fer- 

 tilizer being principally the products of primary protein decomposi- 

 tion, together with a small amount of a proteoselike compound 

 which has persisted. 



From the sample of base goods were isolated the following nitrog- 

 enous compounds, two purine bases, guanine and hypoxanthine ; 

 the three diamino acids, arginine, histidine, and lysine; and two 

 monoamine acids, leucine and tyrosine. A proteoselike compound 

 was also obtained and its general nature established. 



By means of the Van Slyke method the approximate proportions 

 of the different forms of nitrogen contained in the fertilizer were 



