Spodumene, ore

Recovery from Ores and Clays. The preferred method of extraction of lithium from spodumene ore is the sulfuric acid process (18), used on ore concentrates of 5—6% Li O, representing 62—74% pure spodumene. Methods suitable for extraction from spodumene also can be used for petaUte, because the latter mineral converts to P-spodumene—Si02 soHd solution on heating to a high temperature. 

There has been much interest in making chemicals from brine because of the low expense compared to alternative methods. Lithium, for example, had been mostly produced from spodumene ore, but now most is produced from brine. Those now producing from ore are seriously researching brine reserves and contemplating converting to brine sources before the turn of the century. Similady, solar salt has cost advantages over mined rock salt. Potassium chloride produced from brine has more than doubled from 1980 to 1990. 

Spodumene is by far the most important lithium-containing ore and is used in the manufacture of lithium carbonate. Spodumene ore (benehciated to 3 to 5% Li20) is converted from the alpha form to the beta form by heating to over 1000°C, since the alpha form is not attacked by hot sulfuric acid. The water-soluble lithium sulfate is leached out and reacted with sodium carbonate to yield lithium carbonate from which various salts are derived. 

Derivation Reaction of sulfuric acid with lithium carbonate or with spodumene ore. 

Amblygonite, which is a lithium aluminum fluorophosphate, does not occur in large enough deposits to be worked independently. It is often found in association with spodumene ores. 

Lithium carbonate is primarily produced from two resources salt lake brine and spodumene ore. Their respective modes of exploitation are detailed below. 

However, they are present in such a low concentration (170 ppb - parts per billion) that it would be a highly complex and costly task to industrially isolate lithium chloride from all the other mineral salts in solution. There is only one laboratory in Japan working on this but, even after several years of research and improvement, ultimately yielding a very pure product, their extraction process is far more costly ( 80/kg) than that based on salt lake brines ( 2-3/kg) or spodumene ores ( 6-8/kg). 

Figure 1.77 Crushing section flowsheet at the spodumene ore treatment plant of Gwalia Consolidated Limited, Greenbushes, WA (Hemming, 1993a reprinted courtesy of The Australasian Institute of Mining and Metallurgy).

The tantalum and spodumene ores in 2002 each had their own skip pocket and surface storage bins, and their ore was hoisted daily. However, to accommodate the... 

In the plant in 1988 (Figs. 1.80 and 1.81) the spodumene ore was initially crushed in a three-stage operation, first in a jaw crusher, and then by standard and short head cone crushers, both in closed circuits with screens. The ore was crushed to a... 

The recovery of lithium from spodumene ore was discontinued by Foote in 1984 (1986, USGS, 2000) and the mine and plant placed in a stand-by condition. It was officially closed in 1991 and the mine and plant dismantled in 1994 (USGS, 1997). However, the Kings Mountain conversion plant (converting lithium hydroxide to other lithium products) continued as a major processor of Clayton Valley and Salar de Atacama lithium carbonate into other lithium chemicals and lithium metal. Butyl lithium was produced at their New Johnsonville, Tennessee and Taiwan plants, and many other lithium chemicals were made at their parent company, Chemetall GmbH s plant at Langelsheim, Germany. 

Results of LCA s Heavy Media Separation of Spodumene Ore from the Black Hills, SD (Munson and... 

A detailed laboratory study has been presented by Dresler et al. (1998) on the Roast, Acid-Leach Process that exactly follows the process previously used by the LCA (now EMC) at their North Carolina deposit. It is reviewed here because of the additional details that it supplies on this very effective spodumene process. Their ore was from Wekusko Lake, Manitoba, which as at LCA s deposit was an unzoned and low-grade (0.79% Li) spodumene ore, but with a very small crystal size. Electron micrographs showed that each of the minerals in the ore (Table 1.18) was present as discrete crystals, but the liberation size was quite small. Consequently, they ground the ore to a —212 p,m (—65 mesh) size, and made into a 23% slurry to be agitated and conditioned with 2 kg of sodium hydroxide/mt of ore for 20 min. 

Andrews, H. J. (1958). Lithium Extraction from Run-of-Mine Spodumene Ore. Chem. Eng. Prog. 54(1), 54-55. 

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