Geotermisten altaiden hyödyntäminen litiumtarpeidemme ratkaisemiseksi

Litsiumin yhä suuremman metsästys

With the rise of EVs, the demand for lithium-ion batteries exploded, as did the need for lithium resources. This demand is expected to keep growing exponentially, with only the steepness of this curve in question, depending on the speed of EV adoption.

Lähde: Statista

Tämä on aiheuttanut ongelmia, sillä litiumin louhinta on vaikeaa. Aikaisemmin tämä on johtanut villeihin hintavaihteluihin, mikä on saanut syöttökustannusten vaihdella voimakkaasti akkuihin ja sähköautoihin valmistavien yritysten välillä.

Lähde: Carbon Credit

Tällä hetkellä litiumia tuotetaan enimmäkseen kalliista kivestä tai suolaisista vesisuoloista, jotka molemmat vaativat paljon energiaa tai vettä.

Vaihtoehtona voitaisiin tuottaa litiumia geotermisistä suoloista, jotka löytyvät maanalaisista kerrostumista. Tämä on kuitenkin ollut teknisesti haastavaa.

This might have changed thanks to the work of researchers at Rice University, who published their results in the prestigious publication PNAS (Proceedings of the National Academy of Sciences) under the title “Three-chamber electrochemical reactor for selective lithium extraction from brine¹”.

Mistä litium tulee?

Lithium makes up only 0.002% of the Earth’s crust and is rarely found in concentrated deposits that are commercially viable.

Tällä hetkellä suurin osa maailman akuista ja jalostetusta litiumista tulee Kiinasta. Itse mineraali louhitaan pääasiassa “litiumkolmiosta” (Chile, Argentiina, Bolivia), Kiinasta ja Australiasta.

Lähde: Progress in Natural Science

Tämä on saanut muut maat etsimään vaihtoehtoisia lähteitä, ja maanalaiset suolat (suolavesi) ovat hyvä ehdokas. Esimerkiksi äskettäin on havaittu, että Arkansas saattaa sisältää enemmän litiumia suolassa, joka on öljy‑ ja kaasuesiintymien vieressä, kuin kaikki aiemmin tunnetut litiumivarannot Yhdysvalloissa.

Nämä suolat sisältävät usein suhteellisen korkean litiumkonsentraation. Ongelma on, miten litium saadaan erotettua näistä suoloista, sillä ne sisältävät yleensä monimutkaisen sekoituksen muita mineraaleja.

Koska nämä suolat ovat voimakkaasti konsentroituja, suoraa litiumin louhintaa (DLE) harkitaan vaihtoehdoksi suurille haihtumispadoille, joita on tähän mennessä käytetty.

Lähde: Euronews

Suora litiumin louhinta

Direct extraction targets the lithium atoms through a selective extraction process. This can be achieved through a few different methods:

• Adsorption-based DLE, where the lithium is physically absorbed by a dedicated material.
• Ion Exchange-Based DLE, where the lithium is exchanged against cations (positive ions).
• Solvent Extraction-Based DLE, where an organic liquid solvent absorbs and dissolves the lithium away from the brine.

Lähde: Lithium Harvest

Elektrokemiallinen litiumin louhinta

Another option that has not been explored much is electrochemical lithium extraction. The idea is to use a powerful electric current to separate the lithium from the other minerals in the brine.

As we said, these brines contain many other minerals with similar ionic sizes and charges including magnesium, calcium, sodium, and potassium. This makes any method based on ion properties only difficult, as you need to do it many times to fully select only the lithium.

The alternative could be using electrical current instead, but the brines often contain a lot of chloride ions which can turn into extremely toxic chlorine gas during traditional electrochemical processes to isolate the lithium.

Chlorine gas, also known as halogen, was notably used as a combat gas during World War 1. However, the problem of its production during electrochemical lithium extraction has so far blocked this technology from being commercially used.

Akkuteknologian käyttäminen litiumin louhintaan

Paradoxically, innovations in battery technology might help solve the issue of lithium extraction for the very same batteries. The Rice University researchers used a newly developed lithium-ion conductive glass ceramic (LICGC) membrane, a technology often used in batteries but never before applied to lithium processing. LICGC is a solid electrolyte material that is a good candidate for the building of solid-state batteries.

The membrane is very effective in selectively letting only lithium ions pass through while holding back ions of the other chemicals.

3‑Kammioinen elektrokemiallinen reaktori

Traditional electrochemical reactors for lithium extraction are designed around 2 chambers: the first one contains the targeted brine, and the second contains the extracted lithium.

By adding the LICGC membrane in the middle, the researchers created an intermediary third chamber, where mostly only lithium can pass through the LICGC.

“Our field has long struggled with the inefficiencies and environmental impacts of lithium extraction. This reactor is a testament to the power of combining fundamental science with engineering ingenuity to solve real‑world problems.”

Haotian Wang, Rice associate professor of chemical and biomolecular engineering.

During the tests performed by the researchers, the lithium purity rate achieved 97.5%. Meanwhile, the concentrations of Na+ K+, Mg2+, and Ca2+ were so low that they fell below the detection limit of the researchers instruments.

More importantly, it is especially efficient at keeping away the chloride ions, dramatically reducing the production of chlorine gas. Instead of consuming a lot of power and creating harmful gases, only 6.4% of the total power reacted with chlorine ions in the new design.

 Silti, joitakin ongelmia on korjattava

During their testing, the researchers noticed a sodium ion build‑up on the LICGC membrane. If left unchecked, this build‑up could affect the efficiency of the reactor over time. So until this is solved, the 3‑chamber electrochemical reactor will not be ready for commercial‑scale deployment.

One of the possibilities considered to solve the problem would be to pre‑process the brine to reduce the sodium content.

Another one would be to find specialized membrane coatings to keep the sodium ions from attaching in the first place.

Investointi litiumiin ja akkuteollisuuteen

Lithium‑ion batteries have already changed the world several times, from allowing people to carry advanced electronics everywhere to powering cars with electricity only.

They might still do so again, or other types of batteries, by allowing for a 100% renewable power grid or allowing for airplane electrification when reaching a high enough energy density.

You can invest in battery‑related companies through many brokers, and you can find here, on securities.io, our recommendations for the best brokers in the USA, Canada, Australia, the UK, as well as many other countries.

If you are not interested in picking specific lithium or battery companies, you can also look into biotech ETFs like Amplify Lithium & Battery Technology ETF (BATT), Global X’s Lithium & Battery Tech ETF (LIT), or the WisdomTree Battery Solutions UCITS ETF, which will provide a more diversified exposure to capitalize on the growing lithium and battery industry.

Or you can consult our “Top 10 Battery Metals & Renewable Energy Mining Stocks”.

Suora litiumin louhintayritys

Rin Tinto

Rio Tinto (RIO ) on kaivosalan jättiläinen (maailman toiseksi suurin), jolla on vahva läsnäolo rautakaivoksissa sekä kuparissa, alumiinissa, kullassa, uraanissa ym.

Rio Tinto laajenee nopeasti, erityisesti Simandoun mega‑rautakaivosprojektin Guineassa ja Oyu Tolgoi‑kuparikaivoksen, Mongolian historian suurimman projektin, myötä.

Rio Tinto odotetaan tuottavan 25 % kasvusta maailmanlaajuisessa kuparitarjonnassa seuraavien viiden vuoden aikana.

Äskettäin se on tehnyt massiivisen siirtymän litiumikaivostoimialaan, ostamalla litiumijättiläisen Arcadium Lithiumin, joka syntyi vuonna 2023 Allkem‑ ja Livent‑yhtiöiden fuusiosta, tehden siitä maailman kolmanneksi suurimman litiumintuottajan.

Lähde: Arcadium

The merger created a company in all lithium production and processing steps. Arcadium has expansion plans in place to more than double capacity by the end of 2028

Arcadium Innovations

DLE

Regarding this acquisition, what has been described as “Rio Tinto’s real prize” is Arcadium’s direct lithium extraction (DLE) technology. Arcadium has actually been working on DLE since 1996, in combination with evaporation pounds, and recently made significant progress in making it commercially viable as a stand‑alone extraction method.

Notably, Livent acquired ILiAD Technologies in 2023.

“ILiAD Technology Platform combines a superior lithium selective adsorbent with continuous countercurrent bed processing”

“Livent is the world’s foremost practitioner and largest user of DLE‑based production processes, and we are thrilled that they have recognized the advantages that ILiAD brings to the future of DLE.

It seems that the long‑term expertise of Arcadium with DLE, and the “vast range of lithium laden brines under a wide variety of conditions” of ILiAD were a prime reason for Rio Tinto’s decision to acquire Arcadium, on top of its low valuation due to the cyclical nature of lithium markets.

While in the long run, electrochemical lithium extraction might replace adsorbent‑based methods, it is also likely that experience in scaled‑up DLE will anyway payoff if this becomes the main lithium extraction method in the future.

Lithium Foil

Arcadium also developed LIOVIX, a form of printable lithium foil that could be used to boost battery performances, reduce manufacturing costs, and reduce lithium use.

Lähde: Arcadium

Rio Tinton vihreä profiili

Arcadium’s acquisition firmly put Rio Tinto in the camp of mining industry innovators after its innovation in copper extraction through its venture Nuton. Nuton’s new technology allows for a much higher rate of copper recovery from mined ore.

Rio Tinton alumiinituotanto on vähähiilinen, kiitos vesivoiman, jota käytetään bauxiitin jalostukseen alumiinioksidiksi ja edelleen alumiiniksi.

Rio Tinto on myös investoinut muihin litiumiprojekteihin, äskettäin hankkimalla Ricon‑projektin Argentiinassa ja kiistanalaisen Jadar‑litiumiprojektin Serbiassa (potentiaalisesti Euroopan suurin litiumiprojekti).

Viimeaikaisten hankintojen ja uusien projektien myötä Rio Tinton tulisi yhä enemmän nähdään rautakaivoksena, jonka profiili on yhä vihreämpi ja jonka kasvu on vahvaa kaikissa energiasiirtymään tarvittavissa metalleissa, erityisesti kuparissa, vähähiilisessä alumiinissa ja litiumissa.

Studien viite:

^{1. Feng, Y., Park, Y., Hao, S., Fang, Z., Terlier, T., Zhang, X., Qiu, C., Zhang, S., Chen, F., Zhu, P., Nguyen, Q., Wang, H., & Biswal, S. L. (2024). Kolmikamminen elektrokemiallinen reaktori selektiiviseen litiumin erottamiseen suolasta. Proceedings of the National Academy of Sciences, 121(47), e2410033121. https://doi.org/10.1073/pnas.2410033121}