64 MISCELLANEOUS PAPERS. 



Nicotine is readily soluble in nearly all of the ordinary solvents, 

 and hence there is no difficulty in extracting it completely from 

 tobacco after it has been liberated from its salts by means of a fixed 

 alkali. The separation of the nicotine from ammonia and amid bodies, 

 which are always present in tobacco, is the princijoal problem to be 

 solved in this connection. By using such solvents as ether and 

 ligroin, however, only the nicotine and a portion of the ammonia are 

 contained in the extract, and it is possible to remove subsequently 

 practically all of the ammonia by appropriate methods. 



THE PROPOSED NEW METHOD. 



In endeavoring to devise a method for estimating nicotine suited to 

 our requirements, three principal objects were kept in mind, namely, 

 the use of a comparativeh^ cheap solvent, the extraction of the nico- 

 tine without the use of an extraction apparatus requiring the applica- 

 tion of heat, and the direct titration of the extract without previous 

 distillation. Our j^rocess as finally adoj^ted accomj^lishes all of these 

 ends, as will appear below. 



Gasoline or ligroin was chosen as the most suitable solvent. This 

 is prej)ared by shaking the crude gasoline of 70° with concentrated 

 sulphuric acid and distilling and collecting the distillate coming over 

 between the limits of 60° and 100° C. By using a product with high 

 boiling point, the evaporation which takes place during the filtration 

 of the extract is reduced to a minimum and there is little danger of 

 explosions occurring from the accumulation of the vapors in the 

 atmosphere of the room. A number of 2:)reliminary exj^eriments 

 were carried out to determine the conditions necessary for the com- 

 plete extraction of the nicotine from the tobacco and the effect of 

 varying amounts of ammonia on the results obtained by titration of 

 the extracts. 



PRELIMINARY EXPERIMENTS. 



In order to avoid the iwssibility of the j^resence of organic acids in 

 the extract and to insure the comj^lete extraction of the nicotine, a 

 fixed alkali must be added, and this is best apj)lied in aqueous solu- 

 tion. Gasoline and water are immiscible and their mutual solubility 

 is verv slight, but these facts do not in anv wav hinder or retard the 

 extraction of the nicotine, since the latter is easily soluble in both the 

 water and the gasoline. 



It is necessary to agitate the mixture only occasionally to avoid 

 too great a concentration of the nicotine in the portion of either 

 solvent which happens to be in direct contact with the tobacco. 

 Using the ligroin in quantities of 100 c. c. to 6 or 8 grams or less 

 of tobacco, it was found that the extraction of the nicotine is com- 

 plete at the end of four hours, and when the quantity of the latter in 



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