A September 17, 2025 news item from ScienceDaily announced research from Harvard University focused on more sustainable ways to recycle protein by breaking down keratin,
Key Takeaways
SEAS [School of Engineering and Applied Sciences] researchers have discovered the chemical mechanism by which certain salt compounds break down protein waste, like wool and feathers.
The discovery enables a gentler and more sustainable protein recycling process.
The textile and meat-processing industries produce billions of tons of waste annually in the form of feathers, wool and hair, all of which are rich in keratin – the strong, fibrous protein found in hair, skin and nails.
Turning all that animal waste into useful products – from wound dressings to eco-friendly textiles to health extracts – would be a boon for the environment and for new, sustainable industries. But upcycling proteins is challenging: Breaking down, or de-naturing, proteins into their component parts typically requires corrosive chemicals in large, polluting facilities, keeping any cost-effective protocol out of reach.
Researchers in the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have uncovered key fundamental chemistry of how proteins like keratin de-nature in the presence of certain salt compounds – an insight that could take protein recycling to the next level.
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Caption: An artist’s depiction of hair, made out of keratin, denaturing when ions are present. Credit: Michael Rosnach
A team led by Kit Parker, the Tarr Family Professor of Bioengineering and Applied Physics at SEAS, combined experiments and molecular simulations to better illuminate the chemical mechanisms by which salts cause proteins to unfold. They’ve shown that a solution of concentrated, a salt compound known to break apart keratin, interacts with the protein molecules in a completely unexpected way – not by binding to the proteins directly, as was conventional wisdom, but by changing the structure of the surrounding water molecules to create a setting more favorable for spontaneous protein unfolding.
This insight allowed the researchers to design a gentler, more sustainable keratin extraction process, separating the protein out of solution easily and without the need for harsh chemicals. The process can also be reversed with the same salt mixture, enabling recovery and reuse of lithium bromide denaturants.
The research is published in Nature Communicationsand is also featured in a Behind the Paper blog post.
Inspired by keratin biomaterials
First author Yichong Wang, a graduate student in chemistry who works in Parker’s group, said the research builds on the lab’s longstanding interest in developing keratin biomaterials with shape memory for biomedical applications. They had previously observed that keratin extracted from lithium bromide solvents can form thick, shapeable gels that readily separate from the surrounding solution and solidify almost immediately when placed back in water. While useful, they found the behavior odd, and they wanted to understand it better.
“We thought there might be a gap between current mechanistic understanding of how de-naturation works, and what we were seeing,” Wang said. “That’s when we got very interested in the mechanism itself to see if we could optimize our extraction procedures by explaining this phenomenon better.”
Molecular dynamics reveals shifts in surrounding water
To dig deeper, the team turned to the lab of Professor Eugene Shakhnovich in the Department of Chemistry and Chemical Biology, whose expertise is in protein biophysics. Molecular dynamics simulations led by co-author Junlang Liu allowed them to see that the lithium bromides were not working on the proteins at all, but rather, on the water around them.
It turns out lithium bromide ions cause water molecules to shift into two different populations – normal water, and water molecules that become trapped by the salt ions. As the normal water volume decreases, the proteins start to unfold due to the thermodynamic shift in the environment, rather than being directly ripped apart like in other de-naturation methods. “Making the water less like water, allows the protein to unfold itself,” Wang said. They had similar results by testing simpler proteins like fibronectin, pointing to a universal mechanism.
Better understanding and designing protein extraction methods that are less energy-intensive and less polluting than conventional ones opens potential avenues for protein-upcycling industries. In the Parker lab, using keratin as a substrate for tissue engineering is a major research thrust; having a reliable, sustainable method to extract and re-use such products would bolster their efforts.
What’s more, the process could lay a path for a whole new biomaterials industry, turning a massive waste stream like hair or chicken feathers into low-cost recycled materials, possibly as an alternative for traditional plastics, for example.
The research had many sources of federal support, including the National Institutes of Health (R35GM139571 and R01EY030444) and the National Science Foundation through the Harvard University Materials Research Science and Engineering Center (DMR-2011764). Other funding came from the Health@InnoHK program of the Innovation and Technology Commission, part of the Hong Kong SAR Government; and the Medical and Health Informatics Laboratories at NTT Research, Inc.
Here’s a link to and a citation for the paper,
Entropy-driven denaturation enables sustainable protein regeneration through rapid gel-solid transition by Yichong Wang, Junlang Liu, Michael M. Peters, Ryoma Ishii, Dianzhuo Wang, Sourav Chowdhury, Kevin Kit Parker & Eugene I. Shakhnovich. Nature Communications volume 16, Article number: 6907 (2025) DOI: https://doi.org/10.1038/s41467-025-61959-9 Published online: 26 July 2025 Version of record: 26 July 2025
This paper is open access.
There’s also an August 1, 2025 posting by Yichong Wang and Kit Parker (two of the paper’s authors) on SpringerNature’s Behind the Paper blog,
From Hofmeister’s Curiosity to an Interesting Mechanism
In 1888, Franz Hofmeister published a curious observation: salts affect protein solubility in water in systematic ways. This led to the famous “Hofmeister Series,” a ranking of ions based on their ability to precipitate or solubilize proteins. Over the next century, many studies expanded on these observations of salt-induced effects on protein folding, but a unifying theory explaining how ions influence protein structure remained elusive.
Our recent study originated from a practical challenge rather than a theoretical hypothesis. In our lab’s ongoing work to study the shape memory effect of regenerated keratin — a structural protein abundant in wool, hair, and feathers — we observed some puzzling behaviors. When keratin is extracted using concentrated lithium bromide (LiBr), it does not form a fully solubilized protein solution. Instead, we observed that the proteins spontaneously aggregate into a thick, cohesive gel that can be readily separated from the surrounding solution. More unexpectedly, this protein gel solidifies almost immediately upon rehydration, without the need for dialysis or removal of the denaturants. These phenomenon contrasted sharply with the behavior observed when using organic denaturants such as urea or guanidine hydrochloride.
Illustration by Michael Rosnach (Disease Biophysics Group, Harvard University)
None of these phenomenon matched existing explanations for how LiBr supposedly works. If LiBr denatures proteins by directly binding to them, why would the keratin spontaneously separate out of solution? Why would it renature so quickly just by being placed back in water? …
The scientific team of Dr. Miloslav Polášek at IOCB Prague has developed a new method of separating the rare earth elements, or lanthanides, which are widely used in the electronic, medical, automotive, and defense industries. The unique method allows metals such as neodymium or dysprosium to be purified from used neodymium magnets. The environmentally friendly process precipitates the rare earths from water without organic solvents or toxic substances. The results were published in the Journal of the American Chemical Society (JACS) at the end of June [2025].
Global demand for rare earths is driven primarily by their use in extremely strong neodymium magnets, which enable efficient conversion of motion into electrical energy and vice versa. They are essential to manufacturers of electric cars, wind power plants, mobile phones, computers, and data centers. As these industries develop, demand for rare earths will continue to grow. However, the process of mining and purifying these elements is highly energy intensive and produces large amounts of toxic and radioactive waste.
The rare-earth market is dominated by China, giving it leverage over Europe and North America. It is therefore strategically advantageous to focus on so-called urban mining, i.e. the recycling, renewal, and reuse of materials from discarded equipment, such as electric vehicles, as a significant domestic source of rare earths.
“In the future, we won’t be able to cover the growing consumption of rare earths with primary mining. We know that within ten years at the latest, it will be necessary to manage these materials more carefully. In order to achieve this, the development of new technologies must start now,” explains Miloslav Polášek, head of the Coordination Chemistry group. “Our method solves the fundamental problems of recycling neodymium magnets. We can separate the right elements so that new magnets can be produced. Our process is environmentally friendly, and we believe that it will work on an industrial scale. Fortunately, unlike plastics, chemical elements don’t lose their properties through repeated processing, so their recycling is sustainable and can compensate for traditional mining.”
The topic, which Polášek’s group has been working on for a long time, is part of Kelsea G. Jones’s doctoral thesis. “We’ve developed a new type of chelator, which is a molecule that binds metal ions. This chelator specifically precipitates neodymium from dissolved magnets, while dysprosium remains in solution, and the elements are easily separated from each other. The method is also adaptable for the other rare earths found in neodymium magnets,” says Jones. “The separation is done in water and generates no hazardous waste. We achieve the same or better results than current industrial methods that rely on organic solvents and toxic reagents.”
The new technology is patented and responds to a fundamental global problem at the right time. “We’re impatiently awaiting the results of a feasibility study, which will help us direct this research from the laboratory into practice. I believe that in cooperation with the investors and business partners we’re approaching, this new technology from IOCB Prague has the potential to influence a wide range of industrial sectors,” says Milan Prášil, director of the transfer company IOCB Tech.
This research has also yielded another important finding: namely, that the element holmium is used in neodymium magnets of newer electric cars. Scientists from Polášek’s team discovered this by analyzing samples from the electric motors of European and Chinese cars. However, professional publications have not yet mentioned this fact, and most recycling projects do not take it into account when processing waste from electric cars. These findings will undoubtedly influence other development and recycling projects, even beyond the automotive industry.
This is a problem many of us can relate to, is the plastic recyclable and where do I put it for recycling? I have two stories about solutions to these recycling issues.
The future of plastic recycling may soon get much less complicated, frustrating and tedious.
In a new study, Northwestern University chemists have introduced a new plastic upcycling process that can drastically reduce — or perhaps even fully bypass — the laborious chore of pre-sorting mixed plastic waste.
The process harnesses a new, inexpensive nickel-based catalyst that selectively breaks down polyolefin plastics consisting of polyethylenes and polypropylenes — the single-use kind that dominates nearly two-thirds of global plastic consumption. This means industrial users could apply the catalyst to large volumes of unsorted polyolefin waste.
When the catalyst breaks down polyolefins, the low-value solid plastics transform into liquid oils and waxes, which can be upcycled into higher-value products, including lubricants, fuels and candles. Not only can it be used multiple times, but the new catalyst can also break down plastics contaminated with polyvinyl chloride (PVC), a toxic polymer that notoriously makes plastics “unrecyclable.”
The study will be published on Tuesday (Sept. 2 [2025]) in the journal Nature Chemistry.
“One of the biggest hurdles in plastic recycling has always been the necessity of meticulously sorting plastic waste by type,” said Northwestern’s Tobin Marks, the study’s senior author. “Our new catalyst could bypass this costly and labor-intensive step for common polyolefin plastics, making recycling more efficient, practical and economically viable than current strategies.”
“When people think of plastic, they likely are thinking about polyolefins,” said Northwestern’s Yosi Kratish, a co-corresponding author on the paper. “Basically, almost everything in your refrigerator is polyolefin based — squeeze bottles for condiments and salad dressings, milk jugs, plastic wrap, trash bags, disposable utensils, juice cartons and much more. These plastics have a very short lifetime, so they are mostly single-use. If we don’t have an efficient way to recycle them, then they end up in landfills and in the environment, where they linger for decades before degrading into harmful microplastics.”
A world-renowned catalysis expert, Marks is the Vladimir N. Ipatieff Professor of Catalytic Chemistry at Northwestern’s Weinberg College of Arts and Sciences and a professor of chemical and biological engineering at Northwestern’s McCormick School of Engineering. He is also a faculty affiliate at the Paula M. Trienens Institute for Sustainability and Energy. Kratish is a research assistant professor in Marks’ group, and an affiliated faculty member at the Trienens Institute. Qingheng Lai, a research associate in Marks’ group, is the study’s first author. Marks, Kratish and Lai co-led the study with Jeffrey Miller, a professor of chemical engineering at Purdue University; Michael Wasielewski, Clare Hamilton Hall Professor of Chemistry at Weinberg; and Takeshi Kobayashi a research scientist at Ames National Laboratory.
The polyolefin predicament
From yogurt cups and snack wrappers to shampoo bottles and medical masks, most people interact with polyolefin plastics multiple times throughout the day. Because of its versatility, polyolefins are the most used plastic in the world. By some estimates, industry produces more than 220 million tons of polyolefin products globally each year. Yet, according to a 2023 report in the journal Nature, recycling rates for polyolefin plastics are alarmingly low, ranging from less than 1% to 10% worldwide.
The main reason for this disappointing recycling rate is polyolefin’s sturdy, stubborn composition. It contains small molecules linked together with carbon-carbon bonds, which are famously difficult to break.
“When we design catalysts, we target weak spots,” Kratish said. “But polyolefins don’t have any weak links. Every bond is incredibly strong and chemically unreactive.”
Problems with current processes
Currently, only a few, less-than-ideal processes exist that can recycle polyolefin. It can be shredded into flakes, which are then melted and downcycled to form low-quality plastic pellets. But because different types of plastics have different properties and melting points, the process requires workers to scrupulously separate various types of plastics. Even small amounts of other plastics, food residue or non-plastic materials can compromise an entire batch. And those compromised batches go straight into the landfill.
Another option involves heating plastics to incredibly high temperatures, reaching 400 to 700 degrees Celsius. Although this process degrades polyolefin plastics into a useful mixture of gases and liquids, it’s extremely energy intensive.
“Everything can be burned, of course,” Kratish said. “If you apply enough energy, you can convert anything to carbon dioxide and water. But we wanted to find an elegant way to add the minimum amount of energy to derive the maximum value product.”
Precision engineering
To uncover that elegant solution, Marks, Kratish and their team looked to hydrogenolysis, a process that uses hydrogen gas and a catalyst to break down polyolefin plastics into smaller, useful hydrocarbons. While hydrogenolysis approaches already exist, they typically require extremely high temperatures and expensive catalysts made from noble metals like platinum and palladium.
“The polyolefin production scale is huge, but the global noble metal reserves are very limited,” Lai said. “We cannot use the entire metal supply for chemistry. And, even if we did, there still would not be enough to address the plastic problem. That’s why we’re interested in Earth-abundant metals.”
For its polyolefin recycling catalyst, the Northwestern team pinpointed cationic nickel, which is synthesized from an abundant, inexpensive and commercially available nickel compound. While other nickel nanoparticle-based catalysts have multiple reaction sites, the team designed a single-site molecular catalyst.
The single-site design enables the catalyst to act like a highly specialized scalpel — preferentially cutting carbon-carbon bonds — rather than a less controlled blunt instrument that indiscriminately breaks down the plastic’s entire structure. As a result, the catalyst allows for the selective breakdown of branched polyolefins (such as isotactic polypropylene) when they are mixed with unbranched polyolefins — effectively separating them chemically.
“Compared to other nickel-based catalysts, our process uses a single-site catalyst that operates at a temperature 100 degrees lower and at half the hydrogen gas pressure,” Kratish said. “We also use 10 times less catalyst loading, and our activity is 10 times greater. So, we are winning across all categories.”
Accelerated by contamination
With its single, precisely defined and isolated active site, the nickel-based catalyst possesses unprecedented activity and stability. The catalyst is so thermally and chemically stable, in fact, that it maintains control even when exposed to contaminants like PVC. Used in pipes, flooring and medical devices, PVC is visually similar to other types of plastics but significantly less stable upon heating. Upon decomposition, PVC releases hydrogen chloride gas, a highly corrosive byproduct that typically deactivates catalysts and disrupts the recycling process.
Amazingly, not only did Northwestern’s catalyst withstand PVC contamination, PVC actually accelerated its activity. Even when the total weight of the waste mixture is made up of 25% PVC, the scientists found their catalyst still worked with improved performance. This unexpected result suggests the team’s method might overcome one of the biggest hurdles in mixed plastic recycling — breaking down waste currently deemed “unrecyclable” due to PVC contamination. The catalyst also can be regenerated over multiple cycles through a simple treatment with inexpensive alkylaluminium.
“Adding PVC to a recycling mixture has always been forbidden,” Kratish said. “But apparently, it makes our process even better. That is crazy. It’s definitely not something anybody expected.”
Here’s a link to and a citation for the paper,
Stable single-site organonickel catalyst preferentially hydrogenolyses branched polyolefin C–C bonds by Qingheng Lai, Xinrui Zhang, Shan Jiang, Matthew D. Krzyaniak, Selim Alayoglu, Amol Agarwal, Yukun Liu, Wilson C. Edenfield, Takeshi Kobayashi, Yuyang Wang, Vinayak Dravid, Michael R. Wasielewski, Jeffery T. Miller, Yosi Kratish & Tobin J. Marks. Nature Chemistry volume 17, pages 1488–1496 (2025) DOI: https://doi.org/10.1038/s41557-025-01892-y Published: 02 September 2025 Version of record: 02 September 2025 Issue date: October 2025
This paper is behind a paywall.
Pink box
While British Columbia (Canada) can’t yer avail itself of the solution (that situation changed, in Vancouver anyway, as of February 2026) offered by Northwestern University (Chicago, US), there is the ‘pink box solution’ as described in a September 11, 2025 article by Chad Pawson for the Canadian Broadcasting Corporation’s (CBC) news online website,
The organization behind B.C.’s recycling system wants residents to do more to keep plastics from going to landfills or ending up as litter — as only 45 per cent of plastic packaging used by residents is recovered for recycling.
“There’s been a lot of hesitancy around recycling, but our model proves that you can have a system that responsibly manages and recycles these plastics,” said Sam Baker, executive director of Recycle B.C.
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In 2024, residents either put into their blue boxes or took to depots 31,362 tonnes of plastic packaging — from Ziploc bags to yogurt containers — of which 98 per cent was recycled, according to Recycle B.C.’s latest annual report.
B.C.’s not-for-profit system, introduced 10 years ago, was the first in North America to require producers to pay for the packaging and paper they create to be recycled, lifting the burden from local governments.
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In 2024, Recycle B.C. recovered 100 per cent of glass made by producers and used by residents, and 92 per cent of paper.
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The recovery of plastic bags and wrapping trails far behind the recovery of things like plastic containers, even though in 2022 Merlin Plastics figured out for Recycle B.C. how to turn flexible plastics into pellets for new products, rather than be burned as fuel.
Baker said there are several reasons for this, ranging from a lack of understanding of how B.C.’s system works and possible distrust in it, to confusion over how to sort items and ultimately the need to take some items to special depots.
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Recycle B.C.’s goal is to raise the recovery rate of all plastics to at least 50 per cent. One way to make gains will be to improve the recovery of flexible plastics, such as bags and wrappers.
Currently most residents need to collect and keep those items and then take them to one of 227 depots spread across the province or one of 53 London Drugs locations, which has recycling kiosks for items not accepted in curbside or multi-unit building pickup.
“London Drugs recognizes that we put a lot of material out into the market,” said Raman Johal, sustainability manager at the retail chain. “So we only feel right that we are responsible for taking some of that material back.”
But the corporate responsibility only works if residents are willing to make the effort to bring in the materials.
Recycle B.C. has a plan to overcome that barrier. In January it launched a pink box, to be used in communities alongside residents’ blue boxes.
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Aubrey Smethurst, a West Vancouver resident who works in marketing, describes the pink box as a “game changer.”
The mother of two says she has long cared about recycling and would go out of her way [emphasis mine] to make sure things like the plastic bags her family used got to depots.
Now she diverts them to her pink box, which gets picked up once a month from her home.
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I’m glad to learn of the pink boxes and hope to see one for my building in the near future. (That day arrived a few weeks ago) and I have a message for Mr. Baker,
Dear Mr. Baker,
I appreciate the ‘pink box’ option but could do without your scolding tone. Depots for recyclables in difficult to reach locations if you don’t have a car/truck. It’s especially difficult if the items in questions are awkwardly shaped.
As for the communication strategies used by organization, those could do with a bit or work. How did you get the message across about the change regarding soft plastics? Life is busy for most of us and putting out a notice on your website and a few notices at London Drugs stores and at your recycling depots is not enough. An article in a newspaper or on a media website is not enough.
Given how ‘media rich’ most people’s environments are, once or twice is not enough.
I suggest you abandon the scolding and simply work on getting the message out.
Sincerely
As much as was possible, Baker’s scolding was removed from Pawson’s article.
Marjolein Lammerts van Bueren has written up an interview with the principals of Nanonow consulting agency, in a Dec. 15, 2016 article for Amsterdam Fashion Week, where they focus on nanotextiles (Note: Links have been removed),
Strong, sustainable textiles created by combining chemical recycling and nanotechnology – for Vincent Franken and Roel Boekel, their nanotechstiles are there already. With their consulting firm, Nanonow, the two men help companies in a range of industries innovate in the field of nanotechnology. And yes, you guessed it, the fashion industry, too, is finding ways to use the technology to its advantage. Fashionweek.nl sat down with Franken to talk about textiles on a nano scale.
How did you come up with the idea for Nanonow?
“I studied Science, Business & Innovations at the VU in Amsterdam. That’s a beta course that focuses on new technologies and how you can bring them to the market, and I specialised in nanotechnology within that. Because of the many – still untapped – opportunities and applications there are for nanotechnology, I started Nanonow with Roel Boekel after I graduated in 2014. We’re a consulting firm helping companies that still don’t really know how they can make use of nanotechnology, which can be used for a whole lot of things.”
Like the textile industry?
“Exactly. Over the last few years, we’ve done research into several different industries, like the waste and recycling industry. Six months ago we started looking at the textile industry, via Frankenhuis, an international textile recycler. When you throw your clothes in the recycling bin, a portion of them are sold on and a portion are recycled, or downcycled, as I call it. They pull the textiles apart, and those fibres – so the threads – are sold and repurposed into things like insulation. Roel and I thought that was a shame, because you’re deconstructing clothes that have often barely been worn just to make a low-value product out of them.”
So you’ve developed an alternative, Nanotechstiles. Tell us about it!
“We actually wanted to make new clothes from the deconstructed clothes. This is already happening via mechanical recycling, where you produce new clothes by reweaving the old textile fibres. But for me, the Holy Grail we’re looking for – I’m a tech guy after all – is the molecules inside the fibres.”
“First, we don’t want to use the existing thread, but instead we want to pull the thread apart completely then put it back together again. This is called chemical recycling and it’s already happening today. You can remove the cellulose fibres from cotton then put them back together to form viscose or lyocell. The downside of that is that the process is pretty expensive and the quality isn’t always that good.”
“Then you also have nanotechnologies, an area that’s developing rapidly and is already being used to strengthen textiles, which makes them last longer. But there are more options for making textiles no-iron, antibacterial – so that it doesn’t start to smell as quickly – or stain resistant. You can also integrate energy-saving electronics into them, or make them water resistant, as you saw last year on Valerio Zeno and Dennis Storm’s BNN TV programme, Proefkonijnen.”
“When you use nanotechnology to make materials smaller, you transform them, as it were, giving them completely different characteristics. So the fact that you can transform materials means that you can also do this with the threads themselves. We believe that when you combine chemical recycling with nanotechnology, what you get is the perfect thread. We call them nanotechstiles, and in the end, they lead to higher quality clothes that are sustainable, as well.”
“The fact that you can transform materials means that you can also do this with the threads themselves”
How far along are you in the research for nanotechstiles?
“We won the TKI Dinalog Take Off in the logistics sector last year with our nanotechstiles idea. That’s a prize for young talent with innovative ideas for economics and logistics. Since then, we’ve been trying to make the concept more concrete. Which recycling methods can we combine with which nanotechnologies? We’re already pretty far along in that research process, but there hasn’t been any clothing produced from it as yet. We’re focusing on cotton because it makes up the largest proportion of waste. At the moment, we’re in talks with the Institut für Textiltechnik at the University of Aken about how we can produce clothes from our nanotechstiles.
Have you also discovered some pitfalls as part of your research?
“The frustrating thing about nanotechnology is that the more you know about it, the less you can do with it. A lot of options are eliminated during the research process. I’ll give you an example. You want to make clothes that don’t smell as quickly? Well, on paper we know that silver kills 99.9% of bacteria, though we haven’t tested it. So then that leaves you with 0.1%, and that percentage can grow exponentially by using the nutrients from other bacteria. So the material in the clothing itself is safe, but what if a few particles come loose in the wash and get into the drinking water? What happens then? A lot of potential options are eliminated as you go through a process like that because they can be dangerous.”
What are the downsides and how can you guarantee that a design is safe?
“A tremendous amount of nanotechnologies are still in the research phase, so they’re too expensive to develop. We’d like to be using some of them now, but it turns out that there are still too many uncertainties to realistically put them into use. It’s essential to apply the principles of safety by design, only using nanotechnologies where the safety concerns have been well thought out. That’s something we’ve been in touch with the Rijksinstituut voor Volksgezondheid en Milieu (Royal Institute for Public Health and the Environment, RIVM) about. We take safety and the environment into account at every step in the production process for nanotechstiles.”
What the biggest challenge to your concept?
“We already know how certain nanotechnologies respond to cotton, but the biggest challenge is to figure out how they respond to recycled fabrics. You have to remember that nanotechnology isn’t just one thing. You can apply it to any material, which gives you thousands of possibilities. The question is, which one do you think is the most important? For example, you can add carbon nanotubes to make a fabric stronger, but then you’d be paying thousands of euros for a single shirt, and no one wants that.”
What’s the next step?
“Right now, we’re trying to get a sort of crowdfunding campaign started amongst businesses. We’re hoping to build relationships with companies like IKEA, who want to use our sustainable and stain-resistant textiles for things like their employee uniforms. So in addition to the subsidies, they’re helping to fund the research in that way. Based on that, we’ll eventually choose a nanotechnology that we can work up into an actual textile.”
I encourage you to read the original article with its embedded images, additional information, and links to more information.
One last comment, nanotechnology-enabled textiles are usually brand new materials so this is the first time I’ve seen a nanotechnology-based approach to recycling textiles. Bravo!
MIT (Massachusetts Institute of Technology) issued two news releases about this research into reclaiming incandescent light or as they call it “recycling light.” First off, there’s the Jan. 11, 2016 MIT Institute of Soldier Nanotechnologies news release by Paola Rebusco on EurekAlert,
Humanity started recycling relatively early in its evolution: there are proofs that trash recycling was taking place as early as in the 500 BC. What about light recycling? Consider light bulbs: more than one hundred and thirty years ago Thomas Edison patented the first commercially viable incandescent light bulb, so that “none but the extravagant” would ever “burn tallow candles”, paving the way for more than a century of incandescent lighting. In fact, emergence of electric lighting was the main motivating factor for deployment of electricity into every home in the world. The incandescent bulb is an example of a high temperature thermal emitter. It is very useful, but only a small fraction of the emitted light (and therefore energy) is used: most of the light is emitted in the infrared, invisible to the human eye, and in this context wasted.
Now, in a study published in Nature Nanotechnology on January 11th 2016 (online), a team of MIT researchers describes another way to recycle light emitted at unwanted infrared wavelengths while optimizing the emission at useful visible wavelengths. …
“For a thermal emitter at moderate temperatures one usually nano-patterns its surface to alter the emission,” says Ilic [postdoc Ognjen Ilic], the lead author of the study. “At high temperatures” – a light bulb filament reaches 3000K! – “such nanostructures deteriorate and it is impossible to alter the emission spectrum by having a nanostructure directly on the surface of the emitter.” The team solved the problem by surrounding the hot object with special nanophotonic structures that spectrally filter the emitted light, meaning that they let the light reflect or pass through based on its color (i.e. its wavelength). Because the filters are not in direct physical contact with the emitter, temperatures can be very high.
To showcase this idea, the team picked one of the highest temperature thermal emitters available – an incandescent light bulb. The authors designed nanofilters to recycle the infrared light, while allowing the visible light to go through. “The key advance was to design a photonic structure that transmits visible light and reflects infrared light for a very wide range of angles,” explains Ilic. “Conventional photonic filters usually operate for a single incidence angle. The challenge for us was to extend the desired optical properties across all directions,” a feat the authors achieved using special numerical optimization techniques.
However, for this scheme to work, the authors had to redesign the incandescent filament from scratch. “In a regular light bulb, the filament is a long and curly piece of tungsten wire. Here, the filament is laser-machined out of a flat sheet of tungsten: it is completely planar,” says Bermel [professor Peter Bermel now at Purdue University]. A planar filament has a large area, and is therefore very efficient in re-absorbing the light that was reflected by the filter. In describing how the new device differs from previously suggested concepts, Soljačić [professor Marin Soljačić], the project lead, emphasizes that “it is the combination of the exceptional properties of the filter and the shape of the filament that enabled substantial recycling of unwanted radiated light.”
In the new-concept light bulb prototype built by the authors, the efficiency approaches some fluorescent and LED bulbs. Nonetheless, the theoretical model predicts plenty of room for improvement. “This experimental device is a proof-of-concept, at the low end of performance that could be ultimately achieved by this approach,” argues Celanovic [principal research scientist Ivan Celanovic]. There are other advantages of this approach: “An important feature is that our demonstrated device achieves near-ideal rendering of colors,” notes Ilic, referring to the requirement of light sources to faithfully reproduce surrounding colors. That is precisely the reason why incandescent lights remained dominant for so long: their warm light has remained preferable to drab fluorescent lighting for decades.
Some practical questions need to be addressed before this technology can be widely adopted. “We will work closely with our mechanical engineering colleagues at MIT to try to tackle the issues of thermal stability and long-lifetime,” says Soljačić. The authors are particularly excited about the potential for producing these devices cheaply. “The materials we need are abundant and inexpensive,” Joannopoulos [professor John Joannopoulos] notes, “and the filters themselves–consisting of stacks of commonly deposited materials–are amenable to large-scale deposition.”
Chen [professor Gang Chen] comments further: “The lighting potential of this technology is exciting, but the same approach could also be used to improve the performance of energy conversion schemes such as thermo-photovoltaics.” In a thermo-photovoltaic device, external heat causes the material to glow, emitting light that is converted into an electric current by an absorbing photovoltaic element.
The last point captures the main motivation behind the work. “Light radiated from a hot object can be quite useful, whether that object is an incandescent filament or the Sun,” Ilic says. At its core, this work is about recycling thermal light for a specific application; “a 3000-degree filament is one of the hottest and the most challenging sources to work with,” Ilic continues. “It’s also what makes it a crucial test of our approach.”
The key is to create a two-stage process, the researchers report. The first stage involves a conventional heated metal filament, with all its attendant losses. But instead of allowing the waste heat to dissipate in the form of infrared radiation, secondary structures surrounding the filament capture this radiation and reflect it back to the filament to be re-absorbed and re-emitted as visible light. These structures, a form of photonic crystal, are made of Earth-abundant elements and can be made using conventional material-deposition technology.
That second step makes a dramatic difference in how efficiently the system converts light into electricity. The efficiency of conventional incandescent lights is between 2 and 3 percent, while that of fluorescents (including CFLs) is currently between 7 and 13 percent, and that of LEDs between 5 and 13 percent. In contrast, the new two-stage incandescents could reach efficiencies as high as 40 percent, the team says.
The first proof-of-concept units made by the team do not yet reach that level, achieving about 6.6 percent efficiency. But even that preliminary result matches the efficiency of some of today’s CFLs and LEDs, they point out. And it is already a threefold improvement over the efficiency of today’s incandescents.
The team refers to their approach as “light recycling,” says Ilic, since their material takes in the unwanted, useless wavelengths of energy and converts them into the visible light wavelengths that are desired. “It recycles the energy that would otherwise be wasted,” says Soljačić.
Bulbs and beyond
One key to their success was designing a photonic crystal that works for a very wide range of wavelengths and angles. The photonic crystal itself is made as a stack of thin layers, deposited on a substrate. “When you put together layers, with the right thicknesses and sequence,” Ilic explains, you can get very efficient tuning of how the material interacts with light. In their system, the desired visible wavelengths pass right through the material and on out of the bulb, but the infrared wavelengths get reflected as if from a mirror. They then travel back to the filament, adding more heat that then gets converted to more light. Since only the visible ever gets out, the heat just keeps bouncing back in toward the filament until it finally ends up as visible light.
I appreciate both MIT news release writers for “Thomas Edison patented the first commercially viable incandescent light bulb” (Rebusco) and the unidentified writer of the 2nd MIT news release for this, from the news release, “Incandescent bulbs, commercially developed by Thomas Edison (and still used by cartoonists as the symbol of inventive insight) … .” Edison did not invent the light bulb. BTW, the emphases are mine.
For interested parties, here’s a link to and a citation for the paper,
A July 20, 2014 news item on ScienceDaily provides some insight into recycling nuclear fuel,
When nuclear fuel gets recycled, the process releases radioactive krypton and xenon gases. Naturally occurring uranium in rock contaminates basements with the related gas radon. A new porous material called CC3 effectively traps these gases, and research appearing July 20 in Nature Materials shows how: by breathing enough to let the gases in but not out.
The CC3 material could be helpful in removing unwanted or hazardous radioactive elements from nuclear fuel or air in buildings and also in recycling useful elements from the nuclear fuel cycle. CC3 is much more selective in trapping these gases compared to other experimental materials. Also, CC3 will likely use less energy to recover elements than conventional treatments, according to the authors.
The team made up of scientists at the University of Liverpool in the U.K., the Department of Energy’s Pacific Northwest National Laboratory, Newcastle University in the U.K., and Aix-Marseille Universite in France performed simulations and laboratory experiments to determine how — and how well — CC3 might separate these gases from exhaust or waste.
“Xenon, krypton and radon are noble gases, which are chemically inert. That makes it difficult to find materials that can trap them,” said coauthor Praveen Thallapally of PNNL. “So we were happily surprised at how easily CC3 removed them from the gas stream.”
Noble gases are rare in the atmosphere but some such as radon come in radioactive forms and can contribute to cancer. Others such as xenon are useful industrial gases in commercial lighting, medical imaging and anesthesia.
The conventional way to remove xenon from the air or recover it from nuclear fuel involves cooling the air far below where water freezes. Such cryogenic separations are energy intensive and expensive. Researchers have been exploring materials called metal-organic frameworks, also known as MOFs, that could potentially trap xenon and krypton without having to use cryogenics. Although a leading MOF could remove xenon at very low concentrations and at ambient temperatures admirably, researchers wanted to find a material that performed better.
Thallapally’s collaborator Andrew Cooper at the University of Liverpool and others had been researching materials called porous organic cages, whose molecular structures are made up of repeating units that form 3-D cages. Cages built from a molecule called CC3 are the right size to hold about three atoms of xenon, krypton or radon.
To test whether CC3 might be useful here, the team simulated on a computer CC3 interacting with atoms of xenon and other noble gases. The molecular structure of CC3 naturally expands and contracts. The researchers found this breathing created a hole in the cage that grew to 4.5 angstroms wide and shrunk to 3.6 angstroms. One atom of xenon is 4.1 angstroms wide, suggesting it could fit within the window if the cage opens long enough. (Krypton and radon are 3.69 angstroms and 4.17 angstroms wide, respectively, and it takes 10 million angstroms to span a millimeter.)
The computer simulations revealed that CC3 opens its windows big enough for xenon about 7 percent of the time, but that is enough for xenon to hop in. In addition, xenon has a higher likelihood of hopping in than hopping out, essentially trapping the noble gas inside.
The team then tested how well CC3 could pull low concentrations of xenon and krypton out of air, a mix of gases that included oxygen, argon, carbon dioxide and nitrogen. With xenon at 400 parts per million and krypton at 40 parts per million, the researchers sent the mix through a sample of CC3 and measured how long it took for the gases to come out the other side.
Oxygen, nitrogen, argon and carbon dioxide — abundant components of air — traveled through the CC3 and continued to be measured for the experiment’s full 45 minute span. Xenon however stayed within the CC3 for 15 minutes, showing that CC3 could separate xenon from air.
In addition, CC3 trapped twice as much xenon as the leading MOF material. It also caught xenon 20 times more often than it caught krypton, a characteristic known as selectivity. The leading MOF only preferred xenon 7 times as much. These experiments indicated improved performance in two important characteristics of such a material, capacity and selectivity.
“We know that CC3 does this but we’re not sure why. Once we understand why CC3 traps the noble gases so easily, we can improve on it,” said Thallapally.
To explore whether MOFs and porous organic cages offer economic advantages, the researchers estimated the cost compared to cryogenic separations and determined they would likely be less expensive.
“Because these materials function well at ambient or close to ambient temperatures, the processes based on them are less energy intensive to use,” said PNNL’s Denis Strachan.
The material might also find use in pharmaceuticals. Most molecules come in right- and left-handed forms and often only one form works in people. In additional experiments, Cooper and colleagues in the U.K. tested CC3’s ability to distinguish and separate left- and right-handed versions of an alcohol. After separating left- and right-handed forms of CC3, the team showed in biochemical experiments that each form selectively trapped only one form of the alcohol.
The researchers have provided an image illustrating a CC3 cage,
Breathing room: In this computer simulation, light and dark purple highlight the cavities within the 3D pore structure of CC3. Courtesy: PNNL
Here’s a link to and a citation for the paper,
Separation of rare gases and chiral molecules by selective binding in porous organic cages by Linjiang Chen, Paul S. Reiss, Samantha Y. Chong, Daniel Holden, Kim E. Jelfs, Tom Hasell, Marc A. Little, Adam Kewley, Michael E. Briggs, Andrew Stephenson, K. Mark Thomas, Jayne A. Armstrong, Jon Bell, Jose Busto, Raymond Noel, Jian Liu, Denis M. Strachan, Praveen K. Thallapally, & Andrew I. Cooper. Nature Material (2014) doi:10.1038/nmat4035 Published online 20 July 2014
An Oct. 31, 2013 news item on Azonano features information about rare earth elements and their use in technology along with a new technique for recycling them from wastewater,
Many of today’s technologies, from hybrid car batteries to flat-screen televisions, rely on materials known as rare earth elements (REEs) that are in short supply, but scientists are reporting development of a new method to recycle them from wastewater.
The process, which is described in a study in the journal ACS [American Chemical Society] Applied Materials & Interfaces, could help alleviate economic and environmental pressures facing the REE industry.
… Attempts so far to recycle them from industrial wastewater are expensive or otherwise impractical. A major challenge is that the elements are typically very diluted in these waters. The team knew that a nanomaterial known as nano-magnesium hydroxide, or nano-Mg(OH)2, was effective at removing some metals and dyes from wastewater. So they set out to understand how the compound worked and whether it would efficiently remove diluted REEs, as well.
To test their idea, they produced inexpensive nano-Mg(OH)2 particles, whose shapes resemble flowers when viewed with a high-power microscope. They showed that the material captured more than 85 percent of the REEs that were diluted in wastewater in an initial experiment mimicking real-world conditions. “Recycling REEs from wastewater not only saves rare earth resources and protects the environment, but also brings considerable economic benefits,” the researchers state. “The pilot-scale experiment indicated that the self-supported flower-like nano-Mg(OH)2 had great potential to recycle REEs from industrial wastewater.”
Here’s a link to and a citation for the published paper,
As for the short supply mentioned in the first line of the news item, the world’s largest exporter of rare earth elements at 90% of the market, China, recently announced a cap according to a Sept. 6, 2013 article by David Stanway for Reuters. The Chinese government appears to be curtailing exports as part of an ongoing, multi-year strategy. Here’s how Cientifica‘s (an emerging technologies consultancy, etc.) white paper (Simply No Substitute?) about critical materials published in 2012 (?), described the situation,
Despite their name, REE are not that rare in the Earth’s crust. What has happened in the past decade is that REE exports from China undercut prices elsewhere, leading to the closure of mines such as the Mountain Pass REE mine in California. Once China had acquired a dominant market position, prices began to rise. But this situation will likely ease. The US will probably begin REE production from the Mountain Pass mine later in 2012, and mines in other countries are expected to start operation soon as well.
Nevertheless, owing to their broad range of uses REE will continue to exert pressures on their supply – especially for countries without notable REE deposits. This highlights two aspects of importance for strategic materials: actual rarity and strategic supply issues such as these seen for REE. Although strategic and diplomatic supply issues may have easier solutions, their consideration for manufacturing industries will almost be the same – a shortage of crucial supply lines.
Furthermore, as the example of REE shows, the identification of long-term supply problems can often be difficult, and not every government has the same strategic foresight that the Chinese demonstrated. And as new technologies emerge, new elements may see an unexpected, sudden demand in supply. (pp. 16-17)
Meanwhile, in response to China’s decision to cap its 2013 REE exports, the Russian government announced a $1B investment to 2018 in rare earth production,, according to a Sept. 10, 2013 article by Polina Devitt for Reuters.
For those who like to get their information in a more graphic form, here’s an infographic from Thomson Reuters from a May 13, 2012 posting on their eponymous blog,
Rare Earth Metals – Graphic of the Day Credit: Thomson Reuters [downloaded from http://blog.thomsonreuters.com/index.php/rare-earth-metals-graphic-of-the-day/]
There is a larger version on their blog.
All of this serves to explain the interest in recycling REE from industrial wastewater. Surprisingly,, the researchers who developed this new recycling technique are based in China which makes me wonder if the Chinese government sees a future where it too will need to import rare earths as its home sources diminish.
Don’t get the recycling bins yet as carbon nanotube recycling isn’t quite ready to implemented, from the Jan. 23, 2013 news item on Nanowerk,
Carbon nanotubes (CNTs) are set to become an important material for the future. That’s because they are light, robust, and highly conductive, both electrically and thermally whilst still being chemically stable. They are used in broad variety of applications ranging from bicycle components to hydrogen storage. The trouble is that the nanotube manufacturing process is not as sustainable and cost-effective as it could be.
The Jan. 23, 2013 Youris news release by Hywel Curtis, which originated the news item, describes a carbon nanotube recycling project and some of its challenges,
The RECYTUBE project, funded by the European Union, aims to reuse CNT scraps created during production to turn them into new plastic nanocomposites. “Conductive polymers need very specific and expensive fillers, so the project is studying how to recycle CNT production waste to make these fillers more cheaply and easily than is currently done,” explained Pascual Martinez, technical and research engineer at Faperin S.L., Ibi, Spain, one of the project’s technical leads. “We have already produced some injected plastic pieces of reused conductive polymer to demonstrate this.”
The critical test for the project will be whether such a solution is taken up by industry. Some believe the main driver would be to save costs. “There is tremendous growing interest in using reprocessed plastics, both in form of regrinds and re-granulates; mainly due to cost reasons in the commodity sector,” Klaus Mauthner, head of research and development at C-Polymers, Tresdorf, Austria, tells youris.com. He adds: “with nano-composites it could work in the same way.”
There don’t seem to be any details on RECYTUBE website about this recycling technology other than this on the home page,
The aim of RECYTUBE is to develop a methodology to reuse the CNT-containing scraps in the masterbach production, compounding and injection moulding conductive plastic parts. To do so, fast in situ (during production) characterisation of the CNT scraps, based in physical, thermal, mechanical and electrical properties measurements, need to be developed in order to assess which proportion of CNT containing scrap must be added to the virgin polymer to get the desired final properties. Finally, two new products for the production of both an external and an internal conductive plastic part for the automotive Industry [sic] will be developed, adapting to industrial scale the masterbach production, compounding and injection moulding processes reusing CNT scraps.
It seems we’re a very long way off from recycling carbon nanotubes.
According to a Swedish research team at Luleå University of Technology, it’s possible to create cellulose nanofibres from sludge. Well, it’s a particular kind of sludge. From the Feb. 16, 2012 news item on Nanowerk,
For example, at one single cellulose manufacturer, Domsjö Fabrikerna in Sweden, the producer of special cellulose, which is used to in the manufacturing of viscose fibers, causes one thousand tons of sludge as a residue each year.
…
A few years ago, cellulose industries in Sweden, disposed some of their waste as sludge into the ocean. It is now prohibited, and the sludge is stored in large tanks on land. This particular cellulose sludge makes it possible, to produce, so far, the most profitable production of cellulose nanofibres from bio-residue products.
The yield of the manufacture of cellulose nanofibres from the sludge is 95%, compared with cellulose nanofiber production from wood chips 48%, lignin residues 48%, carrot residues of 20%, barley 14% and grass 13%. [emphases mine] “The separation of cellulose nanofibres from bioresidues is energy demanding but when we separate the waste from Domsjö, the energy consumption is lower. The special cellulose from Domsjö has very small size and it also has high cellulose content and therefore the fibers do not need to be chemically pre-treated before the production of cellulose nanofibers,” says Professor Kristiina Oksman.
This is interesting news especially in light of the interview with Jean Moreau (president of CelluForce, a company which manufactures nanocrystalline cellulose [NCC] in Québec, Canada) that I heard yesterday where there was some discussion as to what type of wood is needed to produce it.
In an interview with Dr. Richard Berry (now with CelluForce but with FPInnovations at the time), I asked where the NCC comes from (my Aug. 27, 2010 posting),
Q: Does the process use up the entire log or are parts of it left over? What happens to any leftover bits?
A: We are starting from the bleached chemical pulp which is, to a large extent, cellulose. The left over bits have actually been processed as part of the chemical pulp mill processes. The acid used is recovered and reused and the sugars are converted into other products; in the demonstration plant they will be converted into biogas.
I’m not sure when the ‘spiderphone’ interview took place but it seems to be prior to the manufacturing/demonstration plant’s opening earlier this year (2012). For the curious, here’s a link to the 48 min. interview (roughly 25 mins. Moreau and roughly 25 mins. of questions from callers), http://ccc.spiderphone.com/RealCast/9597937293/Flashcast.html. (Thanks again to David Rougley for dropping by to leave a comment and this link to the interview on an earlier nanocellulose fibre posting [March 28, 2011].)
![Rare Earth Metals - Graphic of the Day Credit: Thomson Reuters [downloaded from http://blog.thomsonreuters.com/index.php/rare-earth-metals-graphic-of-the-day/]](http://www.frogheart.ca/wp-content/uploads/2013/11/rare-earth-metals_ThomsonReuters.jpg)