Natural soda

Capital and operating costs for soda ash production are extremely site specific (29,10). Key factors iaclude iafrastmcture development, freight to consumers, local energy and labor costs, and by-product saleabiUty. 1990 Hst price of bulk natural soda ash was 108/t, F.O.B. Wyoming. 

S. C. HatweU, Natural Soda Ash from Magadi Glass International, March 1982, p. 52. 

Alkalies. In the 1960s, 3.2-34 x 10 t /yr of lime was captively produced by the U.S. alkaH industry for manufacturing soda ash and sodium bicarbonate via the Solvay process. Electrolytic process caustic soda and natural soda ash (trona) from Wyoming have largely replaced the Solvay process. Three of the trona producers in Wyoming now purchase quicklime for producing caustic soda. 

Less than half as much energy is needed to recover sodium carbonate from ores as it is to make it synthetically. The enviromnental impact is also less. However, because there is a limited distribution of natural soda ash in the world compared to the wide availability of salt and limestone, synthesis will continue to be a source of sodium carbonate outside the U.S. 

In 1864 Ernest Solvay, a Belgian chemist, invented his ammonia-soda process. A few years later the soda ash price was reduced one third. The Solvay process had completely replaced the LeBlanc method by 1915. The Solvay method is still very popular worldwide. However, in this country large deposits of natural trona ore were found in the 1940s in Green River, Wyoming. In the last few years there has been a tremendous conversion from synthetic to natural soda ash. The first and last Solvay plant in the U.S. closed in 1986 (a large Allied Chemical plant in Solvay, NY). Trona ore is found about 500 m below the surface. It is called sodium sesquicarbonate... 

The preparation of sodium carbonate from impure natural soda, and from the ashes of soda plants, has been already described. Methods have also been suggested for transforming various sodium salts—sulphate, chloride, fluoride, cryolite, nitrate, and felspar—into the carbonate. Many of these are discussed in detail by R. von Wagner s Regesten der Soda/abrik (Leipzig, 1866) and by G. Lunge s A Theoretical and Practical Treatise on the Manufacture of Sulphuric Acid and Alkali (London, 1896). Much of what is said of the sodium salts applies also to the potassium salts, and conversely. 

E. W. Hilgard verified the conclusion and suggested the reaction as an explanation of the formation of natural soda but G. Lunge showed that dil. soln. are required, and on evaporation, the reaction is reversed. H. Taylor (1851) used barium bicarbonate under similar conditions and R. von Wagner showed that a clear soln. of barium bicarbonate decomposes sodium sulphate, forming barium sulphate and sodium bicarbonate, and that a comparatively small proportion of the bicarbonate will complete the reaction between barium carbonate and sodium sulphate. 

Near the end of the eighteenth century the difference between the two fixed alkalies—potassium and sodium carbonates—was known sodium carbonate barilla was largely made from the ashes of sea plants, and potash from the ashes of land plants. The Arabs also had brought some natural soda into Europe, via Spain. These sources were not sufficient to cope with the demand for alkali for the manufacture of soap, glass, etc. Potash was at that time the cheaper and dominant alkali. With the steadily increasing demands for alkali and the very limited sources of supply presented by the incineration of wood, many attempts were naturally made to substitute the base of common salt, because that with a suitable method of extraction nature has provided inexhaustible, abundant, and cheap... 

An unspecified process had been operated for 20 years using synthetic sodium carbonate powder (soda-ash) to neutralise the hydrogen chloride as it was formed by interaction of the amine and chloro compound in a non-aqueous (and probably flammable) solvent in a steel reactor. Substitution of the powdered sodium carbonate by the crystalline sodium carbonate—sodium hydrogencarbonate double salt ( trona, natural soda ) caused a reduction in the rate of neutralisation, the reaction mixture became more acid, and attack on the steel vessel led to contamination by iron. These changed conditions initiated exothermic side reactions, which eventually ran out of control and caused failure of the reactor. Subsequent laboratory work confirmed this sequence and showed that presence of dissolved iron(III) was necessary to catalyse the side reactions. 

The oldest of the major industrial chemicals in use today is soda ash. It seems to date back to 3000 to 4000 B.C. because beads and other ornaments of glass, presumably made with soda ash, were found in Egyptian tombs. It seems a natural soda ash was used as an article of trade in ancient Lower Egypt. [3]... 

Synthetic soda is of superior quality compared to mined natural soda ash. There are two important grades of carbonates light soda ash and dense soda ash. Light soda ash can absorb large amounts of liquid material onto its surface and remains dry [3]. 

Weathering of silicate minerals usually supplies cations in addition to Ca and Mg. Such waters with [HCO ] > 2[Ca ] (residual alkalinity) tend upon evaporation to increase their pH values and concentrations of HCO and C03 and to decrease [Ca ]. Upon extensive evaporation, such waters acquire a composition similar to that found in natural soda lakes eventually alkaline brines of the Na-C03-S04-Cl type may be formed. 

CAS 497-19-8. Na,C0) NaHC0) 2H20. A natural sodium sesquicarbonate and the most important of the natural sodas. 

A chemical reaction of an aromatic amine with a chloronitro compound went out of control due to ferric chloride catalysed side reactions when the reaction mass became acidic. Natural soda ash used as an acid acceptor in the non-aqueous system was ineffective. The exothermic side reactions developed pressures above those normally encountered in the process. Synthetic soda ash had been used for all previous batches over a 20-year period. The difference in crystallinity made the natural soda ash less effective than the synthetic type normally used and it acted like an undercharge of soda ash. This permitted an acid build-up which formed ferric chloride as the reactor was made of stainless steel. 

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