25
Lithium [Li, 3]
25.1 INTRODUCTION
Lithium (Li), the lightest metal of the group 1 in the periodic table of elements, is
widely and uniformly distributed throughout the Earth’s crust, within the range
of 20–25 mg/kg. It is likely to be concentrated in acidic igneous rocks (up to 40 mg/kg)
and in argillaceous sedimentary rocks and phosphate rocks (up to 75 mg/kg).
Its concentration in coal is <75 mg/kg, but in fly ash may be accumulated up to
240 mg/kg.
World mine Li production (without the United States) in 2010 was 25,300 t, of
which Chile produced 8,800; Australia produced 8,500; and Argentina produced
2,900 (USGS 2011). Lithium is used in organic synthesis, plastic production,
ceramic and glass applications, special alloys, and batteries. Demand for Li batteries
is increasing, as they are used in calculators, cameras, computers, electronic games,
watches, and other devices. Compounds of Li are used as psychiatric medications.
25.2 SOILS
The mean background Li contents in the worldwide soils range from 13 to 28 mg/kg,
within the range of 2–175 mg/kg (Table 25.1). The lowest abundance of Li is in sandy
soils, and the highest is in heavy loamy and calcareous soils. However, the lowest Li
content (mean 1.3 mg/kg) is in organic soils. Surface soils of the Piedmont region
of the southeastern United States contain Li from 11.5 to 33.3  mg/kg, and from
the Coastal Plains, within the range of 3.7–5.8 mg/kg. Higher contents of Li are in
deeper soil horizons, and the greatest amount was found in the mother rocks, up to
59.9 mg/kg (Anderson et al. vide Kabata-Pendias 2011). Mean Li contents of agricultural soils of Poland varies from 6 to 15 mg/kg, in light and heavy soils, respectively
(Siebielec et al. 2012). Lithium contents of soils in Spitsbergen, Norway, are within
the range of 0.23–3.18  mg/kg (Gulińska et  al. 2003). Mean Li content in organic
surface soils of Norway is 0.64 mg/kg, and is lower than the mean value (1.1 mg/kg)
for all investigated soils (Nygard et al. 2012).
During weathering, Li is released easily from the primary minerals in oxidizing
and acid media, and is then incorporated into clay minerals and Fe–Mn hydroxides, accumulated in phosphate rocks, and is also easily absorbed by organic matter.
Li content in soils is controlled more by conditions of the soil formation than by
its initial content in parent rocks. Li distribution in soil profiles follows the general
trends of soil solution circulation; however, it may be highly irregular. In the arid climatic
zones, Li follows the upward movement of the soil solution, and may precipitate at
top horizon, along with easily soluble salts of chlorites, sulfates, and borates. These
reactions explain a relatively higher Li content of soils such as solonchaks, solonetz,
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