Explore the latest insights from top science journals in the Muser Press daily roundup (September 17, 2025), featuring impactful research on climate change challenges.
In brief:
New electrical flash method rapidly purifies red mud into strong ceramics, aluminum feedstock
This new technique, published in American Chemical Society Applied Materials and Interfaces, involves a brief electrical pulse lasting under one minute along with a small amount of chlorine gas. If implemented on a larger scale, it could revolutionize global waste management and materials recovery.
The process uses flash Joule heating (FJH), which rapidly heats materials with a short, high-power electrical pulse to vaporize harmful metals, leaving behind a residue rich in aluminum. This aluminum-rich material can then be repurposed into durable ceramic tiles or bricks or resubjected to the normal aluminum production process. The breakthrough offers a practical and scalable solution to address a significant pollution problem by transforming it into valuable materials, marking an advancement in industrial waste recovery.
“Our research presents a potential game-changing solution for the red mud crisis,” said James Tour, the T.T. and W.F. Chao Professor of Chemistry, professor of materials science and nanoengineering and the study’s corresponding author. “This advance is massive from an industrial perspective, turning what was once a toxic liability into a valuable asset in under one minute.”
Turning toxic waste into tiles
Each year, millions of tons of red mud accumulate as toxic waste from aluminum production, which contains harmful metals. Disasters related to its storage have caused river contamination and flooding in affected communities. The researchers aimed to explore whether this waste could be repurposed rather than merely contained.
The FJH method works by delivering electricity in a flash, similar to a bolt of lightning, while simultaneously introducing chlorine gas. This approach selectively vaporizes iron and other toxic metals, leaving behind the aluminum.
“The speed and simplicity of this method set it apart,” said Qiming Liu, a postdoctoral researcher at Rice and a co-first author of the study. “In just 60 seconds, we extracted 96% of the iron and nearly all the toxic species, while retaining almost all the aluminum.”
This process is significantly faster and cleaner than traditional methods, which often require prolonged heating in furnaces or the use of corrosive chemicals. The new method uses no water and no solvents while also removing the sodium salts in the process, relieving the end use of the typically caustic red mud.
A promising route to sustainability
This method could benefit industries dealing with other high-volume waste streams such as steel manufacturing, mining and rare earth processing, said Shichen Xu, a postdoctoral researcher at Rice and co-first author of the study.
“What was once an environmental threat can now be transformed into building materials,” Xu said. “We have turned cleaned red mud into ceramics that are super hard, making them suitable for construction and aluminum recovery.”
The approach offers a threefold advantage: reducing waste piles, cutting greenhouse gas emissions and decreasing the need for new bauxite mining. For communities affected by red mud disasters, this development signifies renewed hope through applied science.
“This is not just about red mud; it’s about changing our perspective on waste,” Tour said. “If we can apply this method to other industrial residues, it could represent the beginning of a new era in sustainable materials recovery.”
The process, Tour said, is being scaled by the Rice spinoff company, Flash Metals USA, a division of Metallium Ltd., and deployed in partnership with aluminum production companies around the world.
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The research was funded by the Air Force Office of Scientific Research and the U.S. Army Corps of Engineers.
Journal Reference:
Qiming Liu, Shichen Xu, Phelecia Scotland, Justin Sharp, Yi Cheng, Jaeho Shin, Nicholas Lowell Viscomi, Lucas Eddy, Shihui Chen, Bowen Li, Tengda Si, Carter Kittrell, Mine G. Ucak-Astarlioglu, and James M. Tour, ‘Iron and Heavy Metal Removal from Bauxite Residues by Flash Joule Heating with Chlorination’, ACS Applied Materials & Interfaces (2025). DOI: 10.1021/acsami.5c13121
Article Source:
Press Release/Material by Marcy de Luna | Rice University
Tropical rainforest soils may fuel climate change as the Earth warms
A new study led by the U.S. Forest Service, with Chapman University as a key senior collaborator, published in Nature Communications, suggests the Earth’s own tropical soils may contribute to climate change as global warming continues, releasing vast amounts of carbon dioxide (CO₂) as they warm and potentially accelerating a dangerous feedback loop.
Tropical forests have long been viewed as critical allies in the fight against climate change, natural systems that absorb excess carbon and cool the planet. But this new research shows that warming itself is causing these forests’ soils to release enormous amounts of CO₂, essentially flipping the script.
This matters to everyone. If rainforests begin acting as carbon sources instead of sinks, it could accelerate global warming far faster than previously predicted, affecting everything from sea-level rise and extreme weather to food security and public health. Understanding these feedback loops is essential if we are to prepare for, and hopefully prevent, the worst impacts of a rapidly changing climate.
The international research team, including Chapman Assistant Professor of Biological Sciences Dr. Christine Sierra O’Connell, found that soil respiration in a Puerto Rican rainforest increased by 42–204% in experimentally warmed plots, one of the largest CO₂ release rates ever recorded in a terrestrial ecosystem. The findings position belowground ecosystems as critical players in the global climate crisis.
“This research shows that as the planet warms, tropical soils may begin to amplify that warming,” said O’Connell. “If these patterns persist across time and regions, we may be drastically underestimating the extent to which tropical forests will lose carbon and accelerate climate change.”
The study simulated a future climate scenario by raising atmospheric temperatures 4 °C using infrared heaters, marking the first such experiment in a tropical rainforest. Conducted through the TRACE (Tropical Responses to Altered Climate Experiment) project, which includes undergraduate researchers from Chapman University working alongside faculty in the field, the work suggests that microbes, not plant roots, were responsible for the dramatic CO₂ increases. These findings are significant because soils store more carbon than the atmosphere and all terrestrial plants combined. Releasing that carbon could amplify warming globally.
“We are witnessing a troubling shift,” O’Connell added. “The very systems we rely on to stabilize the climate may now be pushing us in the opposite direction.”
Researchers from the USDA Forest Service, US Geological Survey, University of Vermont, Morton Arboretum, and Michigan Technological University also contributed to the study.
Journal Reference:
Wood, T.E., Tucker, C., Alonso-Rodríguez, A.M. et al., ‘Warming induces unexpectedly high soil respiration in a wet tropical forest’, Nature Communications 16, 8222 (2025). DOI: 10.1038/s41467-025-62065-6
Article Source:
Press Release/Material by Bob Hitchcock | Chapman University
Warming temps alone fail to trigger increased CO₂ levels from soil
The findings provide another piece of the puzzle reflecting the role nature plays in the delicate balancing act between carbon storage in soil and carbon dioxide emissions into the atmosphere.
Much of the carbon dioxide emissions from soil come from microbes, tiny organisms like bacteria, fungi, viruses and others, that live in soil and “breathe out” carbon dioxide – just like people.
“When things warm up, there is more plant photosynthesis, more ‘food’ for microbes to metabolize on, more activity for microbes,” said Debjani Sihi, an assistant professor with joint appointments in NC State’s Department of Plant and Microbial Biology and Department of Crop and Soil Sciences and corresponding author of a paper describing the research. The paper appears in Biogeochemistry.
“The question here is whether warming was enough to cause more carbon dioxide release from soil. The findings show that if you don’t have the carbon and nutrients in easily available forms that soil microbes need to grow and thrive, then heating alone will not increase the loss of carbon.”
Sihi added that adding heat and nutrients alone also did not increase carbon dioxide emissions from the studied soil, which came from a long-term field-warming experimental site in the southeastern United States. Soil carbon in an easily available form was required for carbon dioxide levels from soil to increase.
Until recently, warming studies have mostly been conducted in cold (e.g., Arctic, boreal or temperate) climates, Sihi said, as researchers attempt to understand the effects in places where a little bit of warming might lead to large changes.
This study, in contrast, examined unfertile soil from a subtropical climate – Athens, Georgia, home to one of the longest-running soil-warming facilities on the planet.
“This study occurs in former cotton fields converted to forest land, not in native forest land,” Sihi said. “Cotton is an exhaustive crop, so the soil doesn’t contain many nutrients or carbon; the soil is not fertile or healthy.”
The researchers gathered soil from the field site and brought it to a lab to undergo heating – up to 2.5 degrees Celsius. They also examined a number of complex pathways in the soil carbon cycle, the process by which carbon is either stored in or expelled from the soil.
Soil holds many different forms of organic matter, from plant material to living and dead microbes, all of which play a part in the carbon cycle. Microbes are constantly searching for food to survive and grow. The researchers tracked how much carbon is stored in these different pools.
“Microbes are breathing and they are getting their energy from carbon. And then they’re also fulfilling their demand of nutrients from the same food that they’re getting,” Sihi said. “Like humans who need a balanced diet – an energy source, proteins, fiber – you can think about a similar parallel with microbes. They use some of the carbon to build biomass. And they will invest some energy to build enzymes that they need to break down complex organic matter into carbon and nutrients in forms that are easy for them to ingest. The remainder will just be expelled, because that’s part of their metabolism.
“Nature emits carbon, but it also absorbs carbon. If you know how much CO₂ comes from the natural system, then you can identify targets for different other industries or economic sectors to reduce carbon emissions.”
Sihi said that ongoing collaborative work is also examining a range of ecosystems, including two field warming experiments from the tropics – Puerto Rico and Panama – to understand how warming influences soil carbon loss.
“It appears in this case that warming alone may not stimulate microbial activities because these microbes actually don’t have a lot of resources to thrive in,” Sihi said. “In other words, depleted microbial resources constrain warming effects.”
Yaxi Du, a former graduate student of Sihi’s, is the first author. Jacqueline Mohan and Paul Frankson from the University of Georgia co-authored the paper and maintained the long-term field-warming experiment used in the study. Greta Franke and Zhilin Chen are undergraduate researchers who assisted in Sihi’s lab.
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Funding for the research was provided by the U.S. Department of Energy’s Environmental System Science Program awards DE-SC0024410 and DE-SC0025314.
Journal Reference:
Du, Y., Mohan, J., Frankson, P. et al., ‘Decoding the hidden mechanisms of soil carbon cycling in response to climate change in a substrate-limited forested ecosystem’, Biogeochemistry 168, 74 (2025). DOI: 10.1007/s10533-025-01265-0
Article Source:
Press Release/Material by Mick Kulikowski | North Carolina State University(NCSU)
Featured image credit: Gerd Altmann | Pixabay
