![]() ![]() When MSRs are built, tens of tonnes of pure Li-7 would be required in each. World demand for Li-7 in PWR cooling systems is about one tonne per year, including about 400 kg annually for 65 US PWRs (Russia uses a different pH control process). In 2013 the US Department of Energy planned to set aside 200 kg of Li-7 in reserve, and has been funding research on production methods. The Nuclear Energy Institute has described Li-7 supply as critically important for the US nuclear industry. Lithium-7’s very low neutron cross-section (0.045 barns) makes it invaluable for nuclear power uses. It is also used in the manufacture of chemical reagents for nuclear power engineering, and as a basic component for preparation of nuclear grade ion-exchange membranes which are used in PWR coolant water treatment facilities. As a fluoride, it is also expected to come into much greater demand for molten salt reactors (MSRs). However, for both purposes it must be very pure Li-7, otherwise tritium is formed by neutron capture (see later section).ĩ9.95% Li-7 hydroxide is used in nuclear power engineering as an additive in PWR primary coolant, at about 2.2 ppm, for maintaining water chemistry, counteracting the corrosive effects of boric acid (used as neutron absorber) and minimizing corrosion in steam generators of PWRs. As hydroxide it is necessary in small quantities for safe operation in pressurised water reactor (PWR) cooling systems as a pH stabilizer, to reduce corrosion in the primary circuit. Lithium-7 has two important uses in nuclear power due to its relative transparency to neutrons. Lithium has two stable isotopes, Li-6 and Li-7, the latter being 92.5% in nature (hence relative atomic mass of natural lithium of 6.94). The remaining lithium is produced through brines in Chile and Argentina, providing 22% and 8% respectively. However, a 2021 report from the International Energy Agency (IEA) suggests that, in the future the use of lithium will be dominated by clean energy technologies, with a 90% share of demand.Īccording to the United States Geological Survey (USGS), the majority of lithium is produced through hard rock mining in Australia and China, producing 49% and 17% of global lithium resources respectively. The balance is used for ceramics and glass, as well as various other uses. This proportion is growing each year, and has risen from about 40% in 2016. The majority of mined lithium (about three-quarters) is used for batteries. Lithium is the lightest metal, which occurs in several hard rock types, notably spodumene, and in brines, hence it is often mined in salt lakes, particularly in South America. The world faces a potential shortage of lithium by 2025 due to rising demand for lithium.Li-6 is a source of tritium for nuclear fusion, through low-energy nuclear fission.Li-7 is a key component of fluoride coolant in molten salt reactors.Li-7 as a hydroxide is important in controlling the chemistry of PWR cooling systems.Lithium is best known today as an ingredient of lithium-ion batteries.
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