Nitrate Chilean

G. E. Ericksen, Geology and Origin of the Chilean Nitrate Deposits, U.S. Government Printing Office, Washington, D.C., 1981. 

Sodium nitrate nitrate [7631-99-4] NaNO, is found in naturally occurring deposits associated with sodium chloride, sodium sulfate, potassium chloride, potassium nitrate, magnesium chloride, and other salts. Accumulations of sodium nitrate have been reported in several countries, but the only ones being commercially exploited are the unique nitrate-rich deposits in Chile, South America. Natural sodium nitrate is also referred to as Chilean saltpeter or Chilean nitrate. 

The armual world production of sodium nitrate was steady throughout the early 1990s. About 85% is suppHed by the natural product. The maximum world production of sodium nitrate occurred around 1930, at 3,000,000 t/yr, but the highest production levels attained by the Chilean nitrate industry (ca 2,900,000 t/yr) occurred in the late 1920s. Synthetic sodium nitrate production peaked in the mid-1930s at 730,000 t/yr. During that period, the Chilean industry production decreased to 1,360,000 t/yr. 

The Chilean nitrate deposits are located in the north of Chile, in a plateau between the coastal range and the Andes mountains, in the Atacama desert. These deposits are scattered across an area extending some 700 km in length, and ranging in width from a few kilometers to about 50 km. Most deposits are in areas of low rehef, about 1200 m above sea level. The nitrate ore, caUche, is a conglomerate of insoluble and barren material such as breccia, sands, and clays (qv), firmly cemented by soluble oxidized salts that are predominandy sulfates, nitrates, and chlorides of sodium, potassium, and magnesium. Cahche also contains significant quantities of borates, chromates, chlorates, perchlorates, and iodates. 

As of 1996 world production of sodium nitrate was about 520,000 metric tons annually. Of this quantity, some 450,000 t (86%) are produced in Chile from natural deposits by SQM Nitratos and distributed worldwide by several affOiates, eg, Chilean Nitrate Corporation in the United States and Nitrate Sales International in Belgium. The remainder, ca 70,000 t, is manufactured mainly in Europe, Japan, and Russia, generally as a by-product of nitric acid production. Additionally, China is known to manufacture some unknown but significant volumes of sodium nitrate for domestic use. 

The first iodine-containing mineral (Agl) was discovered in Mexico in 1825 but the discovery of iodate as an impurity in Chilean saltpetre in 1840 proved to be more significant industrially. The Chilean nitrate deposits provided the largest proportion of the world s iodine until overtaken in the late 1960s by Japanese production from natural brines (pp. 796, 799). 

Chilean Nitrate Educational Bureau, New York, Bibliography of Literature on Minor Ele-... 

The exclusion of Chilean nitrate and all synthetic nitrogenous fertilisers,... 

Iodine is produced in large scale from Chilean nitrate. Iodine occurs in this mineral as sodium iodate, NalOs. The iodate extract of the mineral becomes more concentrated in iodate after sodium nitrate crystaUizes out. The mother liquor is then treated with sodium bisulfite solution to give sodium iodide ... 

Synonyms Chile saltpeter Chilean nitrate soda niter... 

Willis, L. G, Bibliography of References to die Literature on the Minor Elements, 3rd ed., Chilean Nitrate Educational Bureau, 1939, columns 53-128, ibid, 1st suppl, to the 3rd ed., columns 7-30 ibid., 2nd suppl., columns 9-34. 

Guggenheim Process. A process for the manuf of Na nitrate from Chilean nitrate ore, caliche, in which heat is efficiently utilized and handling costs are kept to a minimum... 

Chilean nitrate - [AMMONIA] (Vol 2) - [SODIUMCOMPOUNDS - SODIUM NITRATE] (Vol 22)... 

Materials not allowed include highly soluble mineral fertilisers, whether natural or synthetic, such as potassium chloride, urea, Chilean nitrate, single and triple superphosphate and synthetic insecticides, fungicides and all herbicides. 

There now exist numerous observations of mass-independent isotopic compositions in nature. Most of these have recently been reviewed and will not be repeated here. When the first laboratory measurements of the mass-independent isotope effect were reported by Thiemens and Heidenreich (1983), their occurrence in nature was not expected, except possibly for the early solar system to produce the observed meteoritic CAI data. It is significant to note that, at present, all oxygen-bearing molecules in the atmosphere (except water) possess mass-independent isotopic compositions. These molecules include O2, O3, CO2, CO, N2O, H2O2, and aerosol nitrate and sulfate. Mass-independent sulfur isotopic compositions are also observed in aerosol (solid) sulfates and nitrates and sulfide and sulfate minerals from the Precambrian, Miocene volcanic sulfates, Antarctica dry valley sulfates, Namibian Gypretes, and Chilean nitrates. In addition, martian (SNC meteorites) carbonates and sulfates possess both mass-independent sulfur and oxygen isotopic compositions. These studies have been reviewed recently (Thiemens et al., 2001 Thiemens, 1999). 

Ericksen G. E. (1981) Geology and origin of the Chilean nitrate deposits. Geological Survey Professional Paper 1188, US Geological Survey, 37pp. 

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