Lithium: From Mining to Medicine

Lithium: From Mining to Medicine

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Though it’s not something one hears about that often, lithium – the planet’s lightest metal – has some pretty heavy implications for the environment, the economy and modern life as we know it. Despite being one of the first three chemical elements to form in the Big Bang, along with hydrogen and helium, lithium constitutes just 0.0007% of Earth’s crust and, due to its high reactivity, is only ever found bound to other elements within naturally formed compounds. In spite of this, lithium plays a hugely significant role in the function of today’s society. From cell phones to psychiatry this unassuming metal is the silent battery, quite literally, behind numerous aspects of modern life.

First discovered by Swedish chemist Johann Arfwedson in 1817 within a sample of petalite ore, lithium took its name from lithos, the ancient Greek word for stone, and was isolated using electrolysis four years later. The same process was used by British and German chemists Augustus Matthiessen and Robert Bunsen to produce more substantial quantities of the metal in 1855. Nearly a century later, in 1923, a German conglomerate became the first to produce lithium both on an industrial scale and for commercial use when they added it to the Bahnmetall used for trains’ bearings.

Though lithium was initially obtained through hard-rock mining, its presence in both surface and groundwater brine led to the development of a much cheaper and more sustainable method of extraction: brine water mining. Today, 87% of the global supply comes from the salars (briny lakes) of South America of which those with the highest lithium concentrations are found in Argentina, Bolivia and Chile. Despite being a rather lengthy process, which can take months or even years, the extraction of lithium carbonate (a compound used in lithium-ion batteries and to treat manic depression) from these brine lakes is relatively simple and relies solely on evaporation. Hard-rock mining still accounts for the remaining 13% of the lithium supply with China and Australia leading the way. Although lithium occurs in higher concentration within rock, the process of extracting it has a higher cost, economically and environmentally, than that of brine water mining. However, while one may be relatively more sustainable than the other, the reality is that both methods of extraction are far from ideal, particularly with regards to water, for which excessive consumption and contamination are both major consequences of the lithium industry. Its existence in clay deposits and, abundantly, in sea water provides potential alternatives, as does the development of lithium-ion battery recycling, for which current rates are no more than 5%, but a truly sustainable lithium industry is still a fair way off.

Yet, as is the case with the extraction of most natural resources, despite the drawbacks, we persist. The likes of coal and oil have shown us that the positive impact of a resource on society often outweighs the negative environmental cost. In fact, as was the case with its predecessors, lithium has become so ingrained in the daily aspects of modern life that ceasing or even reducing extraction would likely bring much of today’s society to an inconvenient and juddering halt. Flexible in both form and function, lithium has come a long way from its debut role in the railway industry. Perhaps its most extraordinary use is in the treatment of manic depression episodes experienced by those suffering from bipolar disorder. Lithium carbonate, the raw material extracted from brine water mining, was first found to have mood stabilising abilities by Australian psychiatrist John Cade in the late 1940s. Believing there to be a link between mania and an excess of uric acid in patients’ urine, Cade began injecting guinea pigs with lithium urate (a mixture of lithium and uric acid) to test his theory. Though it was initially introduced solely as a solubilizing agent for the previously insoluble uric acid, the addition of lithium was discovered to have a calming effect on the animals; so much so that human trials were put in place to test the metal’s effectiveness on reducing mania in bipolar sufferers. A correlation was found and, 70 years later, lithium is one of the main medicines used to treat not only the manic episodes associated with bipolar disorder, but also to relieve the periods of severe depression which often occur in between.

Aside from its medical applications, lithium is combined with aluminium and magnesium to form alloys used in armour-plating, bicycle frames and aircraft, as well as making up part of the batteries found in mobility devices, the storage of solar energy and back-up generators for industry, which are particularly important in places like hospitals and tech facilities to prevent the loss of life or data in the event of a power outage. A lesser known use of lithium, upon which we are all heavily reliant, is the lithium-ion battery which differs from regular batteries in that it can be recharged. This means that smartphones, laptops, smart watches; pretty much anything one can charge, will contain lithium. More recently, one of the most significant roles of lithium-ion batteries has been powering electric cars, which require large amounts of lithium. For example, an estimated 63kg of lithium carbonate equivalent is found in the 70kWh battery of a Tesla Model S, to put this into scale; that’s more lithium than there is in 10,000 smartphones!

While the future looks bright on the surface of the lithium industry, the truth lies deep below the Earth in the abundant, but not always abundantly accessible, reserves. As the lithium industry expands at an explosive rate, there is concern that it won’t be able to maintain a sufficient and sustainable supply to meet the growing demand. If there’s hope that lithium production can continue to expand without further damage to the environment, and at a rate with which the economy can keep up, it lies in the development of more sustainable practices, such as the recycling and seawater extraction of lithium, ensuring decreased pollution, land conservation and a general improvement in efficiency. Whatever the answer, if we want to continue enjoying the modern luxuries that lithium enables, more economically, socially and environmentally sustainable and efficient solutions must be implemented, before the battery runs out.

By Theodora Lonsdale

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