deposits

A better way to extract lithium

December 10, 2024 By EarthWise Leave a Comment

Lithium is the critical component in the batteries that power phones and computers, electric cars, and the systems that store energy generated by solar and wind farms. Lithium is not particularly rare, but it is difficult and often environmentally harmful to extract from where it is found.

Traditional ore sources are increasingly difficult and expensive to mine. The largest known deposits of lithium are in natural brines – the salty water found in geothermal environments. These brines also contain other ions like sodium, potassium, magnesium, and calcium, and efficiently separating out the lithium is extremely challenging.

Traditional separation techniques consume large amounts of energy and produce chemical waste, particularly hazardous chlorine gas. These techniques typically suffer from poor selectivity; that is, the process is interfered with by the other ions present in natural brines.

A team of researchers at Rice University has developed a three-chamber electrochemical reactor that improves the selectivity and efficiency of lithium extraction from brines. The middle chamber of the reactor contains a specialized membrane that acts as a barrier to chloride ions, preventing them from getting to the electrode area where they can form chlorine gas.

The new reactor has achieved a lithium purity rate of 97.5%, which means the setup can effectively separate lithium from other ions in the brine and allow the production of high-quality lithium hydroxide, the key material for battery manufacturing.

The Rice University reactor design has the potential to be a game changer for lithium extraction from geothermal brines.

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‘Game changer’ in lithium extraction: Rice researchers develop novel electrochemical reactor

Photo, posted October 21, 2023, courtesy of Simaron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Lithium in Arkansas

April 11, 2024 By EarthWise Leave a Comment

There are more and more electric cars on the road and utilities are installing record amounts of battery storage to back up solar and wind power generation. Both of these things currently use lithium-ion batteries so the need for them keeps growing.

There is actually plenty of lithium in the world. Sources of more than 100 million tons have been identified, which is enough to meet the projected needs for decades. But lithium is not easy, cheap, or environmentally friendly to extract. It is either blasted out of rocks that are then roasted at 2000-degree temperatures, or it is extracted from brine in places like the high Andes where it leaves behind toxic residues. Ramping up lithium production could greatly diminish the environmental benefits derived from green technologies.

A technique called direct lithium extraction, or DLE, may be a possible solution. The lithium is pulled out of brine while leaving other dissolved compounds behind. It is being tested in many places around the world and appears to offer the lowest negative impacts of available extraction technologies.

The Salton Sea area in California has rich deposits of lithium and is a good candidate for DLE. But conditions may be even better in Arkansas whose Smackover Formation is a brine-rich expanse of limestone.

The area was a productive oil field a hundred years ago and then undertook brine-processing in the 1950s to extract bromine. So, the area already has industrial infrastructure and no new land would need to be cleared.

The former oil fields of Arkansas may become an important domestic source of lithium.

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In Rush for Lithium, Miners Turn to the Oil Fields of Arkansas

Photo, posted February 26, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Geologic Hydrogen | Earth Wise

October 20, 2023 By EarthWise Leave a Comment

There is great interest in the potential use of hydrogen as a fuel or an energy storage medium. Unlike hydrocarbon-based fuels, pure hydrogen combustion produces nothing but water as an emission. But most hydrogen used at present is made by reforming natural gas, which is a process that results in carbon dioxide emissions. Thus, the search goes on for cost-effective and energy-efficient ways to make “green hydrogen” that doesn’t result in greenhouse gas emissions.

Researchers at Colorado University Boulder are investigating the potential effectiveness of coaxing hydrogen from subterranean rocks – a commodity known as geologic hydrogen.

When water mixes with iron-rich minerals deep in the earth’s crust, ensuing chemical reactions can generate pockets of hydrogen gas.

The questions are whether it is possible to bring these deposits up to the surface without harming the environment or human communities in the process and whether they can be extracted in large enough quantities to meet growing global energy demands.

The Colorado researchers will conduct experiments both in the lab and hundreds of meters below the earth’s surface to see if it is possible to induce the subterranean rock to make more hydrogen than it normally does. If the hydrogen-producing reactions can be accelerated, then geologic hydrogen could become a clean and abundant energy source.

Geologists have known about hidden underground deposits of hydrogen for a long time, but recent research has found that there may be a lot more of it than once thought. According to a 2022 report by the US Geological Survey, there may be enough hydrogen below ground to supply humanity’s need for fuel for hundreds of years.

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Can rocks produce abundant clean energy? New project to explore

Photo, posted December 26, 2013, courtesy of Juozas Šalna via Flickr.

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A Huge American Lithium Discovery | Earth Wise

October 12, 2023 By EarthWise Leave a Comment

Human history has often been described in terms of a succession of metal ages: the copper age, the bronze age, and the iron age. In many ways, we have now entered the lithium age. The light metal goes into the batteries that power smartphones, electric vehicles, and massive storage banks for the power grid. Lithium has become a critical strategic resource.

As it stands now, the U.S. gets most of its lithium from imports from Australia and South America. Major lithium sources are not commonplace; in 2022 there were only 45 lithium mines in the world. Many of the known deposits are not in North America but in Chile, Bolivia, Argentina, China, and Australia. The current largest known lithium deposits lie beneath the salt flats of Bolivia.

Lithium Americas Corporation, a company dedicated to advancing lithium projects to the stage of production, funded research over the past decade that has identified vast deposits of lithium-rich clay in a dormant volcanic crater along the Nevada-Oregon border. The McDermitt Caldera is estimated to hold between 20 and 40 million tons of lithium, which would make it the largest deposit in the world.

There are many questions still to answer. It is not clear how easy it will be to extract lithium from the clay, in particular how expensive or carbon-intensive it will be. There are also political complexities since the area where the lithium deposit was found is considered to be unceded ancestral land for both the Paiute and Shoshone tribes.

Apart from a dearth of domestic sources of lithium, the US also lags well behind China in lithium processing capabilities. The country has catching up to do in the new lithium age.

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America Just Hit the Lithium Jackpot

Photo, posted April 19, 2020, courtesy of Ken Lund via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Lithium In The Salton Sea | Earth Wise

October 2, 2023 By EarthWise Leave a Comment

The Salton Sea is a shallow, landlocked, extremely salty body of water in the southern end of California. It was formed from an inflow of water from the Colorado River in 1905 in the aftermath of a collapse of a canal during spring floods. At one time, it was a thriving tourist destination and site of real estate speculation. It was also a crucial habitat for migratory birds and various aquatic species.

Over the past 20 years, the Salton Sea has become increasingly desiccated and polluted with agricultural runoff and waste. Rising salinity and the shrinking water supply from the Colorado River has made it uninhabitable for many species.

Recently, the Salton Sea has attracted new attention because of untouched lithium deposits located beneath its shores. The general area has acquired the moniker “Lithium Valley” and has become a place where major energy companies are exploring advanced mining techniques such as Direct Lithium Extraction (DLE). This new technique enables lithium to be captured from brine deposits without resource-intensive open-pit mining or evaporation pond processes.

Lithium is crucial for making the batteries that power electric vehicles. DLE mining has attracted large investments from billionaires like Warren Buffet, Bill Gates, and Jeff Bezos.

Lithium mining has generated major controversies because of its potential to damage the environment. Whether the new mining techniques can avoid these problems and tap into the potential resources near the Salton Sea remains to be seen. According to experts, the aquifers near the Salton Sea hold enough lithium to supply close to 40% of the global demand.

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As Companies Eye Massive Lithium Deposits in California’s Salton Sea, Locals Anticipate a Mixed Bag

Photo, posted October 28, 2021, courtesy of Christian Collins via Flickr.

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Lithium Mining And The Environment | Earth Wise

August 22, 2022 By EarthWise Leave a Comment

The Salar de Atacama in Chile is a large, dry salt flat surrounded by mountain ranges and is one of the driest places on Earth. Parts of the Atacama Desert have gone without rain for as long as people have been keeping track. Water rich in dissolved salts lies beneath this flat surface and it is particularly rich in lithium salts. Forty percent of the world’s known lithium deposits are the in the Salar.

Lithium is the key component of the batteries that power electric cars as well as cell phones and computers. It is an essential part of the transition away from fossil fuels and towards green energy. But it is important that this element is obtained responsibly with minimal damage to the environment.

Lithium, the lightest of the metals, tends to occur in layers of volcanic ash, but reacts quickly with water. It leaches into groundwater and settles in flat basins where it remains in a briny solution. This dense brine often ends up beneath pockets of fresh surface water, which are havens for fragile ecosystems.

A new study by the University of Massachusetts Amherst looked at the hydrological impact of lithium mining in the Salar. The study found that the impact of lithium mining depends critically on how long surface water is in place. Much of the fresh water there is at least 60 years old. Both droughts and extreme rainfall can cause major changes to the surface water that ordinarily comes from mountain runoff. Lithium mining itself only accounts for less than 10% of freshwater usage in the Salar. But the state of the surface water needs to be carefully monitored to protect the ecosystems as the climate continues to change.

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How environmentally responsible is lithium brine mining? It depends on how old the water is

Photo, posted February 21, 2016, courtesy of Jorge Pacheco via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Arctic Methane Starting To Release | Earth Wise

November 24, 2020 By EarthWise Leave a Comment

An international team of researchers has found evidence that frozen methane deposits in the Arctic Ocean have started to be released over a large area of the continental slope off the East Siberian coast. High levels of methane have been detected down to a depth of 1,100 feet in the Laptev Sea near Russia.

The slope sediments in the Arctic contain huge quantities of methane and other gases, known as hydrates. Methane has a warming effect 80 times stronger than carbon dioxide over a 20-year period. The US Geological Survey has identified Arctic hydrate destabilization as one of the four most serious scenarios for abrupt climate change.

The research team aboard a Russian ship said that most of the bubbles they observed coming up from the sea bottom were dissolving in the water, but that methane levels at the surface were four to eight times what would normally be expected.

Frozen methane deposits have been called the “sleeping giants of the carbon cycle.” If these deposit releases were to reach a high enough level, it would be a tipping point that could greatly increase the speed of global warming. With Arctic temperatures now rising more than twice as fast as the global average, the likelihood of a significant release of the frozen methane grows greater all the time.

Temperatures in Siberia were 9 degrees Fahrenheit higher than average from January to June this year. Last winter’s sea ice melted unusually early. This winter’s freeze has yet to begin, which is already a later start than any time on record.

These new discharges of methane are larger than anything found before and are a very worrisome occurrence.

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Arctic methane deposits ‘starting to release’, scientists say

Photo, posted September 26, 2014, courtesy of the Office of Naval Research via Flickr. Photo credit: U.S. Navy photo by John F. Williams/Released.

Earth Wise is a production of WAMC Northeast Public Radio.

Rare Earths From Mining Waste

May 3, 2019 By EarthWise Leave a Comment

The 17 rare earth elements have become important parts of much of modern technology. Despite their name, most of these elements are relatively plentiful in the earth’s crust, but because of their geochemical properties they are typically dispersed and not often found concentrated in minerals. As a result, economically exploitable ore deposits are uncommon. There are no significant sources in the U.S.

Rare earths play important roles in high-performance magnets, electric motors in vehicles, wind turbines, microphones and speakers, and in portable electronics like cell phones. As these applications become ever larger, the need for additional sources of rare earths increases.

Researchers at Idaho National Laboratory and Rutgers University have studied a method for extracting rare-earth elements from mining waste that could greatly increase the world’s supply of these valuable materials.

It turns out that large amounts of rare earths exist in phosphogypsum, a waste product from producing phosphoric acid from phosphate rock. The U.S. alone mined 28 million tons of phosphate rock in 2017. (Phosphoric acid is used in the production of fertilizers and other products).

The researchers estimate that more than a billion tons of phosphogypsum waste sits in piles at storage sites across the U.S. alone. World-wide, about 100,000 tons of rare earth elements per year end up in phosphogypsum waste. This compares to the total current world-wide production of rare earth oxides of 126,000 tons.

The researchers studied methods for extracting the elements from the waste. A method utilizing a common environmental bacterium showed great promise.

There are concerns about residual radioactivity and other environmental issues in dealing with the waste material, but the world’s supply of rare earth elements might become much greater based on this research.

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Critical Materials: Researchers Eye Huge Supply of Rare-Earth Elements from Mining Waste

Photo, posted June 19, 2015, courtesy of David Stanley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fracking And Streams

March 8, 2018 By EarthWise Leave a Comment

Hydraulic fracturing – better known as fracking – is a method of extracting oil and gas from shale deposits in which millions of gallons of freshwater and chemicals are injected into deep underground deposits. There has been a great deal of concern related to the effects that this process has on water quality and also on the stability of the ground in the vicinity of where it takes place.

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