Chile lithium

E. Norris, EMC The Global Lithium Company. Santiago, Chile Lithium Supply and Markets (LSM), 01/2009. 

Sa.Ia.rs and Lakes. Brines having high lithium concentration are found in salars of northern Chile, southwestern Bohvia, and northwestern Argentina. Brines of lower lithium concentration are found in salars in the western United States and the Tibetan Plateau. Brines pumped from beneath the surface of the Salar de Atacama (Chile) and Silver Peak (Clayton Valley, Nevada) are used for commercial production of lithium uti1i2ing solar evaporation (see Chemicals frombrines). The concentration of selected ions in brines from salars and lakes of potential commercial interest worldwide are shown in Table 1. 

A third source of brine is found underground. Underground brines ate primarily the result of ancient terminal lakes that have dried up and left brine entrained in their salt beds. These deposits may be completely underground or start at the surface. Some of these beds ate hundreds of meters thick. The salt bed at the Salat de Atacama in Chile is over 300 m thick. Its bed is impregnated with brine that is being pumped to solar ponds and serves as feedstock to produce lithium chloride, potassium chloride, and magnesium chloride. Seades Lake in California is a similar ancient terminal lake. Brine from its deposit is processed to recover soda ash, borax, sodium sulfate, potassium chloride, and potassium sulfate. 

Occurrence. Numerous brines contain lithium in minor concentrations. Commercially valuable natural brines are located at Silver Peak, Nevada (400 ppm) (40,41), and at Seades Lake, California (50 ppm) (42,43). Great Salt Lake brine contains 40 ppm and is a source not yet exploited. Seawater contains less than 0.2 ppm. Lithium production started at Silver Peak in the 1970s. The concentration of lithium in the brine is diminishing, and now the principal production occurs from brine in the Salar de Atacama, Chile. 

Lithium brines with commercial potential are found in the Altiplano of BoHvia and Argentina, in salt beds of Chile, and in several salt beds in central and western China. 

Recovery Process. Lithium is extracted from brine at Silver Peak Marsh, Nevada, and at the Salar de Atacama, Chile. Both processes were developed by Foote Mineral Corp. The process at Silver Peak consists of pumping shallow underground wells to solar ponds where brines are concentrated to over 5000 ppm. Lithium ion is then removed by precipitation with soda ash to form a high purity lithium carbonate [554-13-2]. At the Atacama, virgin brine with nearly 3000 ppm lithium is concentrated to near saturation in lithium chloride [7447-41 -8]. This brine is then shipped to Antofagasta, Chile where it is combined with soda ash to form lithium carbonate. 

Economic Aspects and Uses. In 1976, one-third of the lithium produced in the United States was extracted from brines of Seades Lake and Silver Peak (44,45). Since then, lithium production at Seades Lake has been discontinued and the lithium concentration at Silver Peak is decreasing. During the 1980s lithium extraction was started at the Salar de Atacama, Chile. This is the largest lithium production plant in the wodd using brine as its raw material. 

New technology and development of brine reserves are increasing each year in the United States and abroad. This affects the uses and price of brine chemicals. For example, development of the Salar de Atacama in Chile in the 1980s as the largest producer of brine lithium in the world has affected lithium production and prices worldwide. Lithium production from Seades Lake brine has been discontinued, and the Silver Peak operation in Nevada is in a slow production decline caused by weaker brine grades. 

In 2008, the world s largest consumer of lithium minerals and compounds was the United States. The major producer of lithium chemicals worldwide was Chile. Other countries involved in lithium production included Argentina, Australia, Brazil, Canada, China, Portugal, the United States, and Zimbabwe. Specific information on U.S. production was not released in order to preserve trade secrets. 

The most important mineral for the industrial extraction of lithium is spodumene (LiAlSi206), which is found together with lepidolite, petalite and amblygonite (all with Li contents of 4 to 7%) and in salt lakes. The largest known reserves are in Chile (largest known deposit), Australia, USA and Canada. The main producer countries are the USA (North Carolina), Chile, Australia, Russia, Zimbabwe, Brazil and China. The worldwide reserves including the lithium content in salt lakes is estimated to be 7.3 10 t (as lithium), of which 60% is in salt lakes. 

The extraction of lithium from brines in the USA (Utah, Nevada), Chile, Bolivia and Argentina is becoming increasingly important. In these proce.sses lithium precipitates out as the poorly soluble lithium carbonate, as a byproduct in the production of other salts (borax, potassium salts, sodium chloride and magnesium chloride). 

Lithium occurs in silicate ores (minerals that principally contain silicon and oxygen) in association with aluminum and the other alkalis The principal ore is spodumene (LiAlSi2Og). Lithium mining occurs mostly in the United States, Russia, China, and Australia, and in addition, it is extracted from salt deposits in Chile. 

The biggest lithium reserves are located in the so-called lithium triangle on the continent of South America where Chile, Argentina tind Bolivia border on each other. Another big occurrence of lithium brines is in China. Considerable lithium mineral reserves can be foimd in Australia, Canada, the USA and China. The other lithium-producing countries such as Portugal and Zimbabwe have few lithium reserves. 

Although lithium reserves are distributed over 20 countries (see Table 22.3), the main reserves are thus concentrated in only a few of them. Chile, USA, Bolivia, China and Argentina hold 66% of the lithium reserves, from which the lithium triangle in South America holds 45% and Chile alone makes up some 26% [20]. 

Lithium carbonate from brines (i.e., solar evaporation processf. The recovery of lithium from brines is a less energy-intensive process and it is therefore extensively used where natural brines are found. Nevertheless, the methods of recovery used vary with the nature of the brines, especially the lithium concentration and the concentration of interfering cations such as magnesium and calcium. Brines are pumped from natural ponds (e.g., Chile, Argentina,... 

According to a report by Roskill Information Services published in 2003, the lithium market is characterized by a high degree of consolidation. Actually, three major producers—Sons of Gwalia in Australia, Tanco in Canada, and Bikita Minerals in Zimbabwe—represent the major lithium mineral producers, while Sociedad Quimica y Minera de Chile SA (SQM) and Sociedad Chilena de Litio (SCL) control the world s supply of lithium carbonate, and Chemetall GmbH of Germany and FMC Corp. of the USA dominate the manufacture of lithium metal and hthium chemicals. 

According to www.lithiumsite.com/markethtml, Chile accounts for nearly half of all world lithium production (in aU forms). Hence, it is a good indicator of the price of lithium. 

Large lithium reserves are available in South America. A resource of special interest is the dried up salt lake Atacama, 2500 m above sea level in northern Chile. The main component is halite, rock salt, NaCl. In cavities a concentrated salt solution is present, in which the lithium content is as high as 0.15%. This solution is transported to nearby Antofagasta. In a chemical factory there the lithium carbonate is prepared from the chloride. This carbonate is an important export product. Lithium-containing brines are also available in Nevada in the USA. The brines are pumped from the ground through a series of open dams. Through solar evaporation over 12 to 18 months the brine increases its lithium concentration to about 0.6%. Soda is added and lithium carbonate precipitates. 

The production of lithium as ores and brines is not published because of the importance of the element in nuclear weapons. The USGS world production value [12.5] for the year 2000 is 14 000 tonnes but does not include US production. Chile produced 5300 tonnes, Australia, China and Russia at least 2000 tonnes each. 

LI Figueroa, Barton S, SchuU W, Razmilic B, Zumaeta O, Young A, et al. Enviroiunental lithium exposure in the North of Chile-I. Natiual water sources. Biol Trace Elem Res 2012 149(2) 280-90. 

Figueroa LT, Razmillic B, Zumeata O, Aranda GN, Barton SA, SchuU WJ, et al. Environmental lithium exposure in the north of Chile-11. Natural food sources. Biol Trace Elem Res 2013 151(1) 122-31. 

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