Industrial lithium production: how it all began

It was in Langelsheim, at the Metallgesellschaft AG plant on the outskirts of this German city, that the first industrial production of lithium took place around a century ago.

Lithium atoms are among the oldest chemical elements in the Universe, 13.8 billion years old. But surprisingly, the first industrial production only took place about a century ago, in 1923.

It all began in Langelsheim, a small town in Lower Saxony, Germany, situated along the Innerste River, on the edge of the Harz Mountains, rich in copper, iron, silver, lead, and zinc ores, and where the extraction and refining of copper and zinc is an age-old activity. It was in this setting that Metallgesellschaft AG, one of the country's largest metallurgical and chemical companies at the beginning of the 20th century, established its first lithium production plant.

Founded in 1881, Metallgesellschaft AG soon had to respond to a challenge of the time: the wheel bearings of the then-new steam trains needed to be made of a metal that would not overheat when transporting large loads at high speed and that was resistant to wear.

Traditionally, tin alloys were used, but during the First World War, the shortage of tin meant that an alternative had to be found. Among those working to find a solution was Jan Czochralski, a German chemist from Metalurgische Gesellschaft AG, a subsidiary of Metallgesellschaft. Czochralski's research led to the development of a new, cheap anti-friction lead alloy that became known as Bahnmetall (literally ‘railway metal’ in German), ‘B metal’ or Lurgi metal. Unlike pure lead (Pb), which can be cut with a table knife and melts at 327.5 °C, this new alloy, which incorporated 0.7% calcium (Ca) and 0.6% sodium (Na), was much harder, proving to be an excellent substitute for tin-based bearings.

To meet the demand for this new Bahnmetall, Metallgesellschaft, which held the patent, acquired the Hans-Heinrich-Hütte metallurgical plant in Langelsheim.

This move would prove crucial to the ‘rediscovery’ of lithium. All because, as a result of further research, a new metal alloy was developed, made with the addition of 0.04% lithium, taking advantage of the raw material in the area. And this mixture worked even better on the very fast and heavy trains!

It was a total change for lithium, which until then had been considered an exotic curiosity, used to treat gout (unsuccessfully) and in fireworks (for the red colour it projected into the sky), but in limited quantities for research or very specific applications.

The clues for the research came from another source. The lithium mined in Langelsheim was used in the production of greases, which were valued for their ability to withstand high temperatures, and also in the glass and ceramics industry, where it was used to improve the heat resistance and transparency of glass.

However, while lead, calcium, and sodium were all produced industrially, lithium was not. In 1920, when the Bahnmetall production line was set up, there was no industrial production of lithium anywhere in the world. So, when the new alloy was developed, the Metallgesellschaft had to create an entire industrial production process to satisfy the new demand for lithium metal.

Although Czochralski was not directly responsible for the production of lithium, he was part of a scientific and industrial environment that promoted the development of new materials, which included this pioneering work.

Around 1923, the company began what would be the first industrial-scale production of lithium for commercial use.

Lithium was first extracted from zinnwaldite, an ore found in granite and pegmatite deposits, especially in regions such as Zinnwald. The process used for this extraction followed the work of French chemist Antoine Nicolas Guntz in 1893, who caused zinnwaldite to be treated with acid and transformed into lithium carbonate (Li2 CO3).

Lepidolite, another mineral, was also processed to produce lithium carbonate, a compound that would become the basis for many other applications. The extraction process involved crushing the mineral, followed by a series of chemical processes that allowed the lithium to be separated from the other components.

Throughout the 1920s and 1930s, demand for lithium continued to grow, fuelled by the expansion of the chemical and metallurgical industries. Recognising the commercial potential of lithium, Metallgesellschaft AG increased production capacity in Langelsheim and began to explore new applications, including axle boxes for German trains over the next thirty years. It wasn't until 1955 that Bahnmetall bearings were eliminated from German railways, replaced by a new system using ball bearings.

The success of production in Langelsheim also set a model for other industries in various locations around the world, helping to establish lithium as an essential resource in the global economy.

Industrial success led to a boom in Bahnmetall production, which in turn created more demand for lithium. Just four years later, the Maywood Chemical Company in New Jersey, USA, also began producing lithium, followed by the Foote Mineral Company, Kerr-McGee and the Lithium Corporation of America (LCA) in the late 1930s/1940s. By the end of the 1940s, lithium had established itself as a valuable chemical speciality.

Today, the lithium plant in Langelsheim, where it all began, is still in operation, and is now owned by the American Albemarle Corporation.