326 CONTRIBUTION TO STUDY OF HYDROXYLAMINE. — MACKAY. 



The addition of sodium carbonate during hydrolysis to 

 neutralize the large excess of acid formed ; 



Increase of length of time of hydrolysis until disappearance 

 of last trace of the oxyaniidosulphonate, 5 or 6 days. 



In order to be able to pass sulphur dioxide into the solution 

 more rapidly without raising the temperature above — S°, a copper 

 vessel forming an annular ring was designed so that the freezing 

 mixture could be put around the outside of the solution, and 

 also in the central bottomless cylinder. The solution to be 

 sulphonated, in the annular space, had thus a large surface 

 exposed to the action of the freezing mixture. The delivery 

 tube was rotated in the ring as before. 



Little or no hydroxylamine was obtained in this way, how- 

 ever ; and a great deal of time was spent in trying to improve 

 other conditions before it was found that the copper had a 

 specific catalytic reducing action on hydroxjdamine salts, con- 

 verting them mainly into ammonium compounds. 



F reparation oj Free H ydroxylamine. 



For the preparation of free hydroxylamine the method of 

 Uhlenhuth^ was followed. When the chloride was used as the 

 basis of preparation, it was necessary to convert it into the 

 phosphate. 500 grams of tertiary sodium phosphate, prepared 

 from the secondary sodium salt by adding the necessary amount of 

 sodium hydroxide and recrystallizing, were dissolved in lOOOcc. 

 of water and added to 273 grams of hydroxylamine chloride 

 dissolved in 600cc. of water. About 200 grams of hydroxy- 

 lamine phosphate separated from the hot filtered solution on 

 cooling. As there was such a large volume of water present, 

 and as the reagents were pure to start with, it was not necessary 

 to recrystallize. 



From 20 to 50 grams of the dried salt, the amount of salt 

 varying with tlie amount of hydroxylamine required, were put 



1. Ann. Chcm. (Liebig), 311, 117 (1900). 



