Saltpeter nitrogen from

In times past, before it was possible to prepare chemically bound nitrogen from atmospheric N2, nitrates were mined as Chile saltpeter in arid regions of Chile and used as fertilizer. Where would such nitrogen fall in the nitrogen cycle shown in Figure 2.2 ... 

The ancients, who didn t have nitric acid, derived their nitrogen from ammonia in urine and/or from distillation of dung and bones to get sal ammoniac. Ammonium compounds behave as weak acids and alchemists usually enhanced them with saltpeter (potassium nitrate, KNO3). 

Until World War I, AN was manufd chiefly by neutralizing, with weak HNO, the NH, present in aqueous by-products of the artificial gas and coking industries. As the HNO, was then manufd from Chile saltpeter, it contained HC1, HNO, and boric acid as impurities, while the gas liquor NH, used contained pyridine and thiocyanates. Consequently, the AN also contained the same impurities. Such An was used in blasting explosives and, to some extent, in mixed fertilizers. In 1913 the manuf of HNO, from NH, produced from atmospheric nitrogen was begun in Europe. This acid was of a higher degree of purity and, as it was neutralized with synthetic NH, the AN produced was much purer than that obtained by the earlier process... 

As a chemist he contributed nothing of note. Hoefer cites a passage from his treatise in Materia Medica, in which he says that saltpeter, (sal petrae) contains a spirit which is of the nature of air and which nevertheless cannot sustain flame, but is rather opposed to it. Though this description would apply to nitrogen, yet as the above statement is accompanied by no further elucidation it seems a rather strained interpretation that nitrogen might have been isolated from saltpeter by Quercetanus.0... 

The land surface part of the nitrogen cycle involves the constant process of nitrogen removal from the biosphere into deposits (in particular, as a result of accumulation of saltpeter on the Earth surface through erosion and alkalification). From the available estimates, H21 3.9 10 4t/km2/yr, with 7/21 < 22, but II2] + IIn = H + Hii + IIrs- This relationship follows from the fact that during... 

Air contains molecular nitrogen and oxygen. They may be separated by liquefaction and fractional distillation along with inert gases, especially argon. Salt or brine can be used as sources of chlorine and sometimes bromine, sodium hydroxide, and sodium carbonate, whereas metals such as iron, aluminum, copper, or titanium as well as phosphors, potassium, calcium, and fluorine are obtained from mineral ores. Saltpeter was once an important source of nitrogen compounds, but today most ammonia and nitrates are produced synthetically from nitrogen gas in the air. 

Meat. For preservation purposes, meat has been cured with added salt (NaCl) and nitrates (saltpeter) since ancient times. With the recognition that nitrate was reduced by microbial action, about 60 years ago, added nitrite began to replace nitrate. The typical red color of cured meat results from the reaction of nitric oxide with myoglobin to form nitrogen monoxide myoglobin, more frequently referred to as nitro-somyoglobin, and with heat, nitrosomyochrome. 

RT-Drucksache No. 47 from 8 Mar 1915,13. Legislaturperiode, II. Session 1914/ 15. The monopoly extended to a) inorganic nitrogenous minerals, above all Chile saltpeter b) synthetic nitrogen compounds like nitric acid, nitrous acid, ammonium gas, and cyanamide and c) nitrogenous fertilizers like sodium, lime, ammonium nitrate, ammonium sulfate, and urea. 

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