Researchers at Georgia Tech have developed a method to harvest rare earth elements (REEs) directly from coal waste.

Anuja Tripathi, a postdoctoral researcher, co-developed this innovative method to recover critical rare earth elements from this industrial waste. 

Working alongside professors Ching-Hua Huang and Xing Xie, Tripathi transformed what she once viewed as a childhood nuisance into a valuable resource. It offers a way to extract the essential materials needed for modern technology from America’s massive stockpiles of coal fly ash.

Mining coal waste

Do not let the name fool you. Rare earth elements are not actually rare. But these are deeply scattered. Finding them in concentrations high enough to mine efficiently is a global game of hide-and-seek.

Yet, modern society cannot function without them. These elements are the invisible muscles inside electric vehicle motors, wind turbines, defense weapons systems, and smartphones.

Right now, the United States relies mostly on foreign supply chains to get them. This heavy dependence creates massive geopolitical and national security vulnerabilities. The pressure is on to find a domestic source. 

The solution sits in America’s coal landfills. Right now, about 2 billion tons of fly ash are trapped in storage ponds and dump sites across the nation.

Left alone, it can leak toxic chemicals into groundwater or spill during major storms.

But coal naturally holds trace amounts of REEs. When coal burns, those valuable elements get left behind in the ash, concentrated and waiting.

Mining it, however, is a dirty business. Conventional extraction requires intense heat and toxic, corrosive acids. It often creates more pollution than it solves.

Without toxic acids

Tripathi’s breakthrough eliminates the harsh chemicals.

Her system relies on a recyclable, salt-based “ionic liquid.” This specialized liquid remains stable under conditions that would cause water-based chemistry to break down completely.

“The beauty of this system is that it works beyond the limits of water,” Tripathi explained.

First, the ionic liquid washes over the ash, acting like a magnet to pull the rare earth elements away from the waste. Next, the scientists zap the liquid with an electrical current. The valuable elements instantly gather onto a collection surface, allowing researchers to scrape them off.

The best part is that the liquid is cleaned and reused. The process is also highly tunable.

The team can target specific metals by adjusting the voltage of the electrical current. At low voltages, the system isolates neodymium — a critical ingredient for the ultra-strong permanent magnets used in clean energy. In initial lab tests, the system successfully recovered nearly half of the available neodymium.

The laboratory chemistry is sound. Now comes the hard part: scale.

Tripathi and her team must prove that this system can handle tons of waste rather than small laboratory batches. It needs to be fast and cheap enough to survive in the commercial market.

If it works, the implications stretch far beyond coal. The same electrochemical process could eventually be used to mine discarded cell phones, dead EV batteries, and old medical waste.

The findings were published in the journal Environmental Science and Technology. 

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A KLM Cityhopper flight touched down in Hamburg, Germany, following a brief journey from Amsterdam. On paper, it looked like any other routine regional connection. In the fuel tanks, however, it was a completely different story.

The passenger aircraft carried a five percent blend of synthetic kerosene, known as e-SAF. This marks the first time a passenger flight has entered Germany powered by the next-generation fuel.

“Sustainably produced aviation fuels will play an important role in decarbonizing aviation in the coming years. Our infrastructure is fully ready, and we actively support airlines in the use of locally produced blends, including through targeted incentives,” said Christian Kunsch, Chairman of the Executive Board of Hamburg Airport.

Aviation’s green scale problem

The synthetic sustainable aviation fuel (e-SAF) was produced by Germany-based manufacturer INERATEC. Made by combining carbon dioxide, water, and renewable electricity, e-SAF can slash an aircraft’s lifecycle emissions by more than 90 percent. 

It was blended with conventional fossil kerosene by MB Energy before being successfully pumped into the aircraft at Amsterdam’s Schiphol Airport. The fuel is clean and safe, and it drops directly into standard jet engines without requiring any modifications to the plane or airport infrastructure.

It is a huge technical success, but a major warning about how hard it is to get the fuel. Aviation is under immense pressure to decarbonize. 

Yet, beneath the celebration lies an uncomfortable truth. Five years ago, KLM operated its very first pioneering e-SAF test flight to Madrid. For that journey, they managed to scrape together 500 liters of the synthetic fuel. For this flight to Hamburg? They could only secure 200 liters.

The numbers are moving backward.

“Today’s flight to Hamburg once again shows that flying on synthetic kerosene is technically possible. But the reality is that the availability of e-SAF lags far behind ambition,” said Marjan Rintel, CEO of KLM. 

While the technology works, the primary obstacle is scaling production to meet Europe’s strict mandate of a 1.2% e-SAF fuel blend by 2030, a target that current manufacturing falls drastically short of. 

This supply gap was highlighted by the complex, small-scale logistics required for this single flight, which relied on fuel produced by INERATEC in Frankfurt, blended by MB Energy, and flown out of Schiphol Airport.

High price

Why is it so hard to get? Money and red tape.

These two heavily restrict the mass adoption of synthetic kerosene, which remains more expensive than standard biofuel-based SAF and eight times pricier than conventional fossil fuels.

Furthermore, expanding supply is severely hindered by slow European environmental and construction permitting processes, making the development of large-scale production facilities a significant challenge.

Still, the partners behind the flight argue that the groundwork has to be laid now. Airport infrastructure is already fully capable of handling the fuel, and clean-tech firms say they are ready to produce it if the economic incentives align

“We are ready to deliver. Today’s flight, with our Chief Commercial Officer Maximilian Backhaus on board during a regular passenger service, clearly shows that power-to-liquid fuels are safe, available, and already operationally viable today. This is just the beginning of many applications we will see this year across various sectors,” said Tim Boeltken, Co-founder and CEO of INERATEC. 

Aviation has proven it can fly on clean air and electricity. Now, the industry just needs to find a way to make more than 200 liters of it at a time.

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Lithium is essential to the modern world, but its extraction has always carried a heavy environmental toll.

A research team from Monash University has patented a new technology that extracts lithium from solid salt mixtures rather than liquid brines. This method provides a faster, highly efficient, and eco-friendly alternative to standard lithium extraction. The process works by shifting the focus from liquid brine to a dried, solid salt crust. Interestingly, it achieved a lithium recovery of around 95 percent.

“This work shows that lithium can be efficiently separated from complex salt mixtures using simple organic solvents, without relying on freshwater or highly chemical-intensive processes,” said Dr. Zhikao Li, one of the study authors. 

No freshwater needed

The global transition to green energy depends on lithium recovered from salt-lake brines, yet the current methods used to harvest it are plagued by critical inefficiencies. 

Standard extraction processes are painfully slow, often requiring up to two years for brine to evaporate in massive desert ponds, all while recovering less than half of the available lithium. 

Newer, faster technologies, such as Direct Lithium Extraction, aim to shorten this timeline. However, these introduce a severe environmental tradeoff by consuming unsustainable volumes of scarce freshwater in the world’s absolute driest regions.

This combination of low recovery rates, prolonged processing delays, and high water demand creates a massive issue for a global supply chain under pressure to scale sustainably.

Rather than pulling lithium from liquid brine, this new approach works backward by targeting the solid salt crust left behind.

Once the brine has dried, engineers wash the resulting salt mixture with common industrial solvents such as ethanol and acetone. 

As lithium dissolves incredibly well in these organic liquids while other coexisting salts do not, the solvents act like a precise chemical magnet and slide the lithium away from impurities. This clever use of differential solubility allows for an exceptionally clean separation, completely eliminating the industry’s reliance on massive freshwater inputs.

Removing impurities

To make the system fully sustainable, the researchers paired the solvent wash with advanced “interfacial solar evaporation” technology. 

Using only natural sunlight, the system traps heat at the surface of the liquid. This accelerates the extraction process and recovers the solvent in its pure form. The team successfully recovered and recycled more than 99% of the ethanol and acetone used.

In addition to saving water, the method also removes boron and sulfate impurities. Typically, these stubborn minerals cling to lithium matrices, requiring complex, chemical-heavy refinement stages to filter them out.

Battery-grade material becomes much easier to produce because this new method naturally rejects contaminants during the initial solvent wash. This yields exceptionally high-purity lithium right from the start and streamlines the entire manufacturing pipeline.

Recognizing its commercial potential, the research team has filed a patent application for this breakthrough technology. 

The process achieves both high extraction rates and near-total solvent recycling, maximizing performance while reducing the ecological footprint of lithium harvesting.

The findings were published in the journal Environmental Science & Technology.

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Engineers at the University of California San Diego have built a tiny optical component measuring just six millimeters in diameter for telescopes.

Developed in collaboration with BAE Systems Space & Mission Systems, the device could simplify space exploration hardware. It promises to slash mission costs while vastly improving the ability to monitor dangerous space weather.

Tiny metasurface technology

A metasurface is an advanced class of nanotechnology consisting of a flat optical component engineered with microscopic, nanoscale structures. 

Using these nanostructures, the device can manipulate light — such as splitting and controlling its polarization channels simultaneously — in unique ways that conventional glass lenses and mirrors physically cannot.

Until now, this tech was mostly an academic parlor trick. “Most academic work on metasurfaces has remained at the proof-of-concept stage,” said Noah Rubin, the study’s senior author and an engineering professor at UC San Diego.

Rubin’s team took the concept out of the lab. Their industry partners at BAE Systems subjected the tiny lens to brutal vibration and extreme temperature testing.

It passed. The nanotech was officially space-qualified.

“We’re excited for the possibility to deploy our technology in space,” Rubin said. “I think this is a very nice example of where fundamental academic research actually can translate to something with real potential for space exploration and science.”

The sun’s magnetic fields are often studied to predict massive solar eruptions, such as coronal mass ejections, that send charged particles toward Earth. 

For this, polarization, or the vibration direction of incoming sunlight, is analyzed. 

Existing space telescopes use a different approach to do this. These take an image, mechanically rotate an optical component, and take another image. And then digitally stitching them together.

This process is slow and vulnerable to the slightest jitters. As spacecraft vibrate, even a tiny nudge between exposures can completely blur delicate solar data.

To stop this, NASA has to build incredibly complex, expensive stabilization systems. “These systems often cost far more than the telescope itself,” Rubin noted.

The new six-millimeter metasurface eliminates the moving parts entirely.

It splits incoming sunlight into several different polarization paths at the exact same time. Instead of a slow sequence of photos, the telescope captures all the magnetic data simultaneously in a single snapshot.

“With these faster frame rates, we can observe phenomena that were too quick for previous instruments to capture,” said Lisa Li, the study’s first author. 

Mapping magnetic fields

To prove the device could actually do real science, the researchers integrated it into a custom telescope and traveled to the Dunn Solar Telescope in New Mexico.

The setup was a contrast of epic proportions. Sunlight hit a mirror at the top of a 136-foot tower, traveled 228 feet underground, and was reflected back to the surface. There, it passed through the team’s tiny six-millimeter component.

The microscopic lens successfully mapped the intense magnetic fields inside active sunspots. When the team compared their data to observations from NASA’s massive, orbiting Solar Dynamics Observatory, the results were nearly identical.

The tiny lens performed just as well as a giant satellite.

Now, the team is setting its sights on the launchpad. Backed by five years of development and funding from NASA, the researchers have submitted a formal proposal for a mission concept study. 

If selected, their tiny six-millimeter eye could soon be riding a rocket into space — proving that sometimes, the biggest breakthroughs come in the smallest packages.

The paper was published on June 10 in Science Advances.

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