Nitrate minerals

Soda niter or sodium nitrate (NaNO ) is the most abundant of the nitrate minerals. It is used for fertilizer, explosives, and preservatives. The natural deposits are located in northern Chile, which was the original source for many years. More recently, nitrogen fixation, which extracts nitrogen from air, has been used for producing sodium nitrate. This synthetic process has greatly increased the availability of this useful sodium salt by ehminating the need for the natural source. It is used to preserve and cure meats and is used in photography, in pharmaceuticals, and as a color fixative in fabrics. 

Fig. 156. Explosive properties of ammonium nitrate-mineral oil mixtures as a function of mineral oil content [71],...

Nitrates. Minerals composed of compounds of a metal with the nitrate radical, NOj. 

Sodium hydroxide Ammonium nitrate Mineral oils... 

Sodium nitrate deposits are less widespread than the other major types of chemical crust or sediment that are found in different parts of the world. Indeed, the only deposits of any great spatial extent and thickness are those of portions of the hyper-arid Atacama Desert in South America. These materials are, in the words of Ericksen (1983, p. 366), so extraordinary that, were it not for their existence, geologists could easily conclude that such deposits could not form in nature . Ericksen notes a series of features of the deposits that defy rational explanation. These include their restricted distribution in a very salty area, their occurrence in a wide variety of topographic settings, the abundance of nitrate minerals, and the presence of a series of other minerals, such as perchlorate, that do not occur in any other saline complexes and the origin of which is obscure. 

Some of the Atacama nitrate deposits are relatively pure sodium nitrate (nitratite or soda niter). This is the case with some near-surface veins in bedrock (Ericksen and Mrose, 1972) and with some caliche bianco. However, most of the deposits are impure and contain substantial amounts of other salts, including a range of sulphates, chlorides, nitrates, borates, iodates, perchlorate and chromates. Ericksen (1981), Pueyo et al. (1998) and Searl and Rankin (1993), provide a detailed list of such minerals (Table 12.1), although some of Searl and Rankin s identifications have been challenged by Ericksen (1994). One of the nitrate minerals, humberstonite, derives its name from Humberstone, one of the nitrate towns in the area (Mrose et al., 1970). Of the impurities, sodium chloride (halite) appears to be the most important and may often exceed the percentage of nitrate (see e.g., Penrose, 1910, p. 14). A detailed chemical analysis of the Maria Elena nitrate deposits is provided by Collao et al. (2002). They report (p. 181) ... 

Borage contains tannins, mucilage, malic acid, potassium nitrate, mineral salts (Tyler, 1993), and approx 20-25% y-linolenic acid (GLA), an co-6 polyunsaturated essential fatty acid (Leventhal et al., 1993 Tyler, 1993). These ingredients are purported to have constipating and astringent properties (tannins), diuretic effects (malic acid and potassium nitrate), and expectorant action (mucilage) (Tyler, 1993). 

Liquid oil-soluble Cl, e.g. sulfated and nitrated mineral oils, and salts of synthetic fatty acids, may render a plasticizing effect on PE thus lowering the degree of crystallinity and the strength of the modified films [106]. Plastification is accompanied by declining intermolecular interactions, which facilitates conformal transformations of macromolecules. 

There are very few nitrate minerals in nature due to their high solubility in water. 

Gerhardite is a green copper nitrate mineral which forms as soft green tabular crystals or as a massive crust, ft has the chemical... 

On acetylation it gives acetanilide. Nitrated with some decomposition to a mixture of 2-and 4-nitroanilines. It is basic and gives water-soluble salts with mineral acids. Heating aniline sulphate at 190 C gives sulphanilic add. When heated with alkyl chlorides or aliphatic alcohols mono- and di-alkyl derivatives are obtained, e.g. dimethylaniline. Treatment with trichloroethylene gives phenylglycine. With glycerol and sulphuric acid (Skraup s reaction) quinoline is obtained, while quinaldine can be prepared by the reaction between aniline, paraldehyde and hydrochloric acid. 

Steam is by far the most widely used medium, useful up to about 475 K. Up to about 700 K organic liquids such as the dowtherms and mineral oil may be used. Mercury and molten salts, such as the eutectic mixture of sodium nitrite, sodium nitrate and potassium nitrate may be used up to 875 K, while above this temperature air and flue gases must be used. 

The salts have been used for centuries to produce brilliant and permanent blue colors in porcelain, glass, pottery, tiles, and enamels. It is the principal ingredient in Sevre s and Thenard s blue. A solution of the chloride is used as a sympathetic ink. Cobalt carefully used in the form of the chloride, sulfate, acetate, or nitrate has been found effective in correcting a certain mineral deficiency disease in animals. 

Gr. neos, new, and didymos, twin) In 1841, Mosander, extracted from cerite a new rose-colored oxide, which he believed contained a new element. He named the element didymium, as it was an inseparable twin brother of lanthanum. In 1885 von Welsbach separated didymium into two new elemental components, neodymia and praseodymia, by repeated fractionation of ammonium didymium nitrate. While the free metal is in misch metal, long known and used as a pyrophoric alloy for light flints, the element was not isolated in relatively pure form until 1925. Neodymium is present in misch metal to the extent of about 18%. It is present in the minerals monazite and bastnasite, which are principal sources of rare-earth metals. 

NITRATION IN AQUEOUS SOLUTIONS OF MINERAL ACIDS 2.4.1 The state of nitric acid in aqueous sulphuric acid Nitric acid is completely converted into nitronium ions in concentrated sulphuric acid ( 2.3.1) ... 

The observation already discussed ( 2.2, 2.3, 2.4) of nitrations, in concentrated and aqueous mineral acids and in pure nitric acid, which depend on the first power of the concentration of the aromatic compound, does not help much in elucidating the mechanisms of nitrations under these conditions. In contrast, the observation of zeroth-order... 

Calcium. Calcium is the fifth most abundant element in the earth s cmst. There is no foreseeable lack of this resource as it is virtually unlimited. Primary sources of calcium are lime materials and gypsum, generally classified as soil amendments (see Calcium compounds). Among the more important calcium amendments are blast furnace slag, calcitic limestone, gypsum, hydrated lime, and precipitated lime. Fertilizers that carry calcium are calcium cyanamide, calcium nitrate, phosphate rock, and superphosphates. In addition, there are several organic carriers of calcium. Calcium is widely distributed in nature as calcium carbonate, chalk, marble, gypsum, fluorspar, phosphate rock, and other rocks and minerals. 

Fluorinated Acids. This class of compounds is characterized by the strength of the fluorocarbon acids, eg, CF COOH, approaching that of mineral acids. This property results from the strong inductive effect of fluorine and is markedly less when the fluorocarbon group is moved away from the carbonyl group. Generally, their reactions are similar to organic acids and they find apphcations, particularly trifluoroacetic acid [76-05-1] and its anhydride [407-25-0] as promotors in the preparation of esters and ketones and in nitration reactions. 

Mineral Deposits. The only iodine obtained from minerals has been a by-product of the processing of nitrate ores in Chile. CaUche occurs in the Atacama desert of Northern Chile and west of the Andes mountains. The Atacama desert is known as the driest of the world s deserts, where measurable (>1 mm) rainfalls may be as infrequent as once every 5—29 years (58). The caUche deposits occur in an area averaging 700 km (north—south) by 30 km (east—west). The iodine may total over 5 x 10 t (59). 

---