Nitrometer Method for Determination

Nitrolit. See 2,4,6-Trinitroanisole A450-L Nitrometer Method for Determination of Nitrogen Content in Nitrates A373 to A3 78... 

Gasometric Method for Determination of Ammonium Nitrate Content by Means of Nitrometer A373 to A377... 

It was shown by the above authors that nitrogen content of nitric esters such as NG or NC cannot be determined by the nitrometer method, if stabilizers such as centralite are present, because centralite absorbs some nitrogen oxides thus giving a low result for N. The difference between the nitrometer N content of NG in absence of a stabilizer and N content of NG in presence of a stabilizer may be taken as an index of stabilizing action of the stabilizer the bigger the difference, the better the stabilizer. This difference is called indice nitrometrique... 

Nitric acid and organic and inorganic nitrates, and in general all substances which contain free nitric acid or yield nitric acid when they are treated with concentrated sulfuric acid, are analyzed by means of the nitrometer. The method depends upon the measurement of the volume of the nitric oxide which is produced when concentrated sulfuric acid acts upon the sample in the presence of mercury. It is satisfactory also for the determination of nitro group nitrogen in certain nitroamines, in nitro-guanidine and in tetryl but not in methylnitramine. It is not satisfactory in the presence of mononitro aromatic compounds or of other substances which are nitrated readily by a solution of nitric acid in concentrated sulfuric acid. 

This method was used for the first time by Ray [6] to determine non-olefinic impurities in ethylene. The sample (10-25 ml) was first fed into a reactor (19 x 1.1 cm) filled with activated charcoal saturated with bromine (40%). The resulting liquid bromina-tion products of ethylene were securely retained on charcoal at room temperature. The zone of non-olefinic impurities (permanent and saturated hydrocarbon gases) moved in a flow of carbon dioxide (carrier gas) from the reactor into a chromatographic column (40 X 0.2 cm I.D.) packed with activated charcoal. A nitrometer was used as the detector [39, 40]. The method permitted the determination of trace concentrations of 10" -10" % in ethylene. The use of a more sensitive detector should substantially lower the detection limit. 

Sodium Nitrate.- Determine moisture and chlorine by the usual methods, and the total, NaNO 3, by means of nitrometer-0.45 grm. is a very convenient quantity to work on (gives about 123 c.c. gas) grind very fine, and dissolve in a very little hot water in the cup of the nitrometer use about 15 c.c. concentrated H 2 SO 4. One cubic cent, of NO equals. 003805 grm. of NaNO 3. The insoluble matter, both organic and inorganic, should also be determined, also sulphate of soda and lime tested for. 

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