Fridges are piling up in laybys across the country as recycling centres refuse to take anymore. It's the backfiring result, in part, of pettifogging green waste disposal regulation, says Ben Pile.
The post Green Rules Mean Britain Can’t Even Recycle a Fridge appeared first on The Daily Sceptic.
In a development that could reshape how chemists recycle one of the most persistent classes of synthetic molecules ever made, researchers have reported a new catalytic strategy that strips fluorine atoms from perfluoroalkyl chains in a controlled, sequential fashion while installing a single boron group at the chain’s terminus. The work, published in Nature Communications, introduces what the authors call zipper polydefluorination-monoborylation, a transformation that walks down a perfluoroalkyl skeleton and removes multiple fluorine atoms in a stepwise cascade before capping the partially defluorinated product with a boron substituent. The achievement addresses a longstanding challenge in fluorine chemistry: while carbon-fluorine bonds are prized in materials and pharmaceuticals for their extraordinary stability, that same stability makes them notoriously difficult to break selectively, leaving chemists with few tools for converting perfluorinated waste streams into useful building blocks.
Perfluoroalkyl substances, often grouped under the umbrella of PFAS chemistry, owe their remarkable properties to the strength of the carbon-fluorine bond, which at roughly 485 kilojoules per mole in fully fluorinated chains ranks among the strongest single bonds that carbon forms. This bond strength, combined with the sheer electronegativity of fluorine, means that perfluoroalkyl groups resist oxidation, hydrolysis, and thermal degradation under nearly all conventional conditions. As a consequence, perfluorinated chains accumulate in the environment and resist standard degradation pathways, prompting intensive research into defluorination methods ranging from photocatalytic single-electron transfer to reductive hydrodefluorination with metal hydrides. Yet most existing approaches suffer from a common limitation: they either remove fluorine indiscriminately, collapsing the entire chain to a mixture of products, or they remove only a single fluorine atom, offering little control over the degree of defluorination. The new study demonstrates a way to achieve the best of both worlds, delivering multi-fluorine removal in a predictable pattern while simultaneously introducing a versatile functional handle.
The conceptual heart of the method lies in what the authors describe as a zipper mechanism. Rather than removing fluorine atoms at random positions along the chain, the reaction initiates at a defined site and then propagates along the perfluoroalkyl backbone one carbon at a time, much as a zipper opens tooth by tooth. At each step along the chain, a fluorine atom is expelled and replaced in sequence, with the reaction front advancing until a thermodynamic or kinetic stopping point is reached. The monoborylation component of the process ensures that once the zipper has run its course, the resulting olefinic or anionic intermediate is intercepted by a boron reagent, furnishing a product in which the boron group occupies a predictable position derived from the original perfluoroalkyl terminus. Organoboron compounds are among the most valuable intermediates in modern synthetic chemistry, serving as partners in Suzuki-Miyaura cross-coupling and as precursors to alcohols, amines, and halides, so their installation at a defluorination site effectively converts a chemical dead end into a synthetic launching pad.
Mechanistically, the transformation draws on the characteristic reactivity of organoboron reagents toward geminal difluoroalkenes, the partially defluorinated intermediates that arise when consecutive fluorine atoms are eliminated from a perfluoroalkyl chain. Perfluoroalkyl chains, when subjected to strong bases or reductive conditions, can undergo sequential beta-fluoride elimination events, each generating a more highly unsaturated species. The boron reagent in the reported system engages these unsaturated intermediates through addition pathways that install boron at the terminal carbon while generating a carbanionic center adjacent to the remaining difluoromethylene unit. That newly formed carbanion is perfectly positioned to expel another fluoride ion, regenerating an unsaturated handle one carbon further down the chain and setting up the next iteration of the cycle. This intimate coupling of borylation and defluorination is what gives the reaction its chain-walking character: each borylation event creates the conditions for the next defluorination event, and the process ripples along the chain until the fluorine reservoir is exhausted or the reagents are consumed.
The practical significance of the work becomes apparent when one considers the fate of the fluorine atoms themselves. In the zipper process, fluorine is released as fluoride ion, which under the reaction conditions is sequestered by silicon-containing trapping agents to form robust silicon-fluorine bonds. Fluorosilicates of this kind are stable, isolable, and, importantly, compatible with industrial processes for recycling fluorine back into hydrofluoric acid, the feedstock from which essentially all synthetic organofluorine compounds are made. In this sense, the method does more than transform perfluoroalkyl chains into borylated products; it also lays the groundwork for closing the fluorine cycle, recovering the fluorine content of persistent molecules in a form that can be fed back into the chemical economy. With global concern over PFAS contamination intensifying and regulatory pressure on fluorinated chemicals mounting, technologies that enable fluorine recovery rather than dilution into the environment carry considerable weight.
From a synthetic chemistry standpoint, the products of the reaction open multiple downstream avenues. Because the boron substituent is installed at a defined position on a partially fluorinated alkyl or alkenyl framework, the resulting molecules retain a programmable mixture of carbon-fluorine bonds and carbon-boron functionality. The remaining fluorine atoms can tune the lipophilicity, metabolic stability, and dipole moment of the scaffold, properties that are actively exploited in medicinal chemistry when designing fluorinated drug candidates. Meanwhile, the boron group serves as a convertible handle, allowing the defluorinated carbon center to be joined to aromatic rings through cross-coupling, oxidized to alcohols, or aminated in homologation reactions. In effect, the method converts a chemically inert perfluoroalkyl group, useful mainly as a passive coating or tail, into a functionalized partial-fluoro skeleton that can participate in the full toolkit of carbon-carbon and carbon-heteroatom bond formation.
The reported study also sheds light on the factors governing how far the zipper travels along a given chain. Chain length, the nature of the substituent anchoring the perfluoroalkyl group, and the stoichiometry of the base and boron reagent all influence the number of fluorine atoms removed and the distribution of products obtained. Through systematic variation of these parameters and careful analysis of the reaction mixtures by nuclear magnetic resonance spectroscopy and mass spectrometry, the authors map out the scope of the transformation across a range of perfluoroalkyl substrates, from short perfluoroethyl groups to longer chains approaching those found in commercial fluorosurfactants. Control experiments interrogating individual elementary steps support the proposed sequential elimination-addition mechanism and rule out alternative pathways involving radical fragmentation or random beta-scission, underscoring the unusually high degree of positional control the method achieves.
Beyond its immediate synthetic utility, the work contributes to a growing body of research aimed at taming the carbon-fluorine bond through the strategy of defluorinative functionalization. Over the past decade, chemists have developed an impressive repertoire of reactions that replace fluorine in perfluoroalkyl and fluoroarene substrates with groups ranging from hydrogen to sulfur, nitrogen, and carbon substituents. What distinguishes the zipper approach is its multiplicity and its directionality: instead of a single substitution event at a single site, the reaction performs many substitutions in a choreographed sequence along a chain, effectively treating the perfluoroalkyl group as a one-dimensional lattice to be patterned at will. This conceptual reframing, from defluorination as bond-breaking to defluorination as programmable editing, may inspire analogous strategies for other polyfluorinated motifs, including perfluoroarenes and perfluoropolyethers, two additional classes of highly persistent fluorinated materials.
Challenges remain before such chemistry can move from the laboratory bench to environmental remediation at scale. The reaction conditions reported rely on strong bases and moisture-sensitive boron reagents handled under inert atmosphere, and the substrates studied are discrete, soluble perfluoroalkyl compounds rather than the polymeric or adsorbed PFAS species that dominate environmental contamination. Scaling the chemistry will require sourcing boron reagents economically, managing the large quantities of fluoride generated, and integrating the transformation with upstream methods for extracting perfluoroalkyl pollutants from water and soil. Nevertheless, the demonstration that a perfluoroalkyl chain can be unzipped in a controlled manner, with fluorine captured in recyclable form and a valuable boron handle installed, establishes a credible chemical pathway toward defluorination that is both productive and selective, a combination that has eluded the field for decades.
As policymakers and scientists grapple with the legacy of fluorine chemistry, work of this kind illustrates a middle path between the wholesale abandonment of fluorinated molecules and their indefinite persistence in the biosphere. The fluorine atom confers properties that industry and medicine continue to depend upon, and the ability to disassemble fluorinated architectures on demand, recovering both the carbon skeleton as a functionalized building block and the fluorine content as a recyclable salt, points toward a more circular future for organofluorine chemistry. The zipper polydefluorination-monoborylation strategy reported in Nature Communications is an early but striking example of that vision made concrete at the molecular level, and it is likely to prompt rapid efforts to extend the concept across the breadth of persistent fluorinated chemicals.
Article Title: Zipper polydefluorination-monoborylation of perfluoroalkyl chains
Article References: Albers, S. L., Harzendorf, J. K., Deliaval, M., Köllmann, J., & Streuff, J. (2026). Zipper polydefluorination-monoborylation of perfluoroalkyl chains. Nature Communications, 17(1), Article 9502. https://doi.org/10.1038/s41467-026-77437-9
Image Credits: AI Generated
DOI: 10.1038/s41467-026-77437-9
Keywords: perfluoroalkyl chains, defluorination, polydefluorinative borylation, organoboron compounds, carbon-fluorine bond activation, PFAS degradation, fluorine recycling, geminal difluoroalkenes, cross-coupling, sustainable chemistry
Apple has increased its estimated trade-in values for most current iPhone, iPad, Mac, and Apple Watch models in the United States. The adjustments give customers slightly more credit toward a new device, although some older Apple hardware and several Android phones have moved in the opposite direction.
The updated values are maximum estimates rather than guaranteed payments. Apple calculates the final credit after confirming the model and inspecting its condition. A damaged display, enclosure problems, missing functionality, or an inaccurate description can reduce the amount offered.
Most of the increases are modest, but they arrive across several of Apple’s largest product categories at the same time. Recent iPhones receive between $10 and $25 more, every iPad category listed in Apple’s summary gains value, and several popular Macs receive larger increases.
The revisions also reinforce the role of trade-ins within Apple’s retail operation. Credit can reduce the cost of a regular purchase, be delivered through an Apple Gift Card, or lower payments at the beginning of an eligible Apple Upgrade lease.
Every iPhone 16 model included in the update receives a higher maximum estimate. The iPhone 16 Pro Max moves from $685 to $695, retaining the highest listed value among the affected iPhones.
The iPhone 16 Pro increases from $550 to $560, while the iPhone 16 Plus moves from $455 to $465. The standard iPhone 16 receives the largest increase within the family, rising by $25 from $435 to $460.
These changes narrow the difference between the standard iPhone 16 and the larger Plus model. The Pro models retain substantially higher estimates, reflecting their higher original prices and stronger position in the used-device market.
An additional $10 or $25 will not transform the cost of an upgrade, but it can offset part of a case, charger, AppleCare plan, or storage upgrade. The difference also becomes more relevant for customers comparing Apple’s direct program with a third-party reseller offering a similar amount.
Apple’s iPad adjustments are more consistent. The maximum estimate for an iPad Pro rises from $670 to $690, an increase of $20. The iPad Air moves from $445 to $460, while the standard iPad rises from $220 to $235.
The iPad mini also gains $15, moving from a maximum of $250 to $265. That means every current iPad category displayed in Apple’s trade-in summary receives a higher estimate.
Apple’s direct trade-in values are generally lower than the prices an owner might obtain through a private sale. The program instead emphasizes convenience: the device can be returned at an Apple Store or sent using Apple’s online process, with the credit connected directly to a new purchase.
A private sale can produce a better return, especially for a recent device in excellent condition. It also requires the owner to set a price, find a buyer, manage payment, and handle the transfer independently. Apple’s program trades some resale value for a simpler exchange.
Mac trade-in values receive some of the largest increases, but the category also includes notable reductions.
The MacBook Air rises from a maximum of $485 to $520, adding $35. The Mac mini receives the same increase, moving from $340 to $375. The MacBook Pro changes only slightly, increasing from $685 to $690.
Apple leaves the current iMac estimate unchanged at $355. The Mac Studio receives a larger increase from $975 to $1,045, reflecting the higher value retained by recent desktop configurations.
Older professional desktops move in the other direction. The iMac Pro falls from $325 to $315, while the top Mac Pro estimate declines from $2,090 to $2,045.
That $45 reduction at the top of the Mac range means Apple’s maximum Mac trade-in offer decreases even though several mainstream models receive more credit. The changes appear more closely connected to the resale position of individual product families than to a uniform increase across every computer.
Mac estimates can vary considerably because one model name can cover different years, processors, memory configurations, storage capacities, and physical designs. Apple asks for a serial number before producing a more specific estimate for a Mac.
The Apple Watch adjustments are similarly mixed. Apple Watch Ultra 2 rises from $295 to $305, while Apple Watch Series 9 increases from $120 to $130.
Apple Watch Series 10 remains unchanged at a maximum of $150. The original Apple Watch Ultra falls from $215 to $205, losing $10.
Wearable trade-in values can decline quickly because watches receive frequent updates and are exposed to greater physical wear than many computers or tablets. Battery condition, display damage, case wear, and working buttons can influence whether the device receives the estimated credit.
Apple also accepts devices that no longer qualify for monetary value. Those products can be returned for recycling, including older hardware and accessories that would otherwise remain unused.
Apple accepts selected smartphones from Samsung, Google, and other manufacturers when customers move to an iPhone. The latest revisions are less favorable to several Android devices.
The maximum Android estimate across Apple’s displayed range decreases from $370 to $360. Individual changes vary by model.
The Samsung Galaxy S23 Ultra drops from $230 to $200, a $30 reduction. Google’s Pixel 8 Pro declines from $170 to $165.
Other devices remain unchanged. The standard Galaxy S23 continues to carry an estimated value of up to $125, while the OnePlus 12 remains at up to $200.
Apple’s Android offers are primarily designed to remove friction for people moving to the iPhone. They do not necessarily match the amount available from the manufacturer, a carrier promotion, or a private buyer.
Carrier promotions can advertise considerably higher trade-in credits than Apple, particularly around a new iPhone launch. Those offers commonly require an eligible unlimited plan, a new line, monthly bill credits, or a commitment lasting two or three years.
Apple’s direct credit is easier to understand because it is tied to the assessed value of the device rather than a long carrier agreement. The best choice depends on whether the customer values flexibility, immediate credit, or the largest possible promotional discount.
Apple’s published figures represent the maximum available for qualifying devices in suitable condition. The online estimate is based on the answers supplied before the product is inspected.
After receiving the device, Apple or its trade-in partner verifies its identity and checks whether it powers on, functions properly, and matches the reported condition. A difference can produce a revised offer.
Customers can accept or reject a lower revised value. Rejecting it cancels the trade-in and returns the device, although the payment arrangement for the accompanying purchase may also be adjusted. If the inspected value is higher than the original estimate, Apple says it automatically increases the credit.
The way the credit is delivered depends on the purchase. When a customer pays in full for a new iPhone, iPad, Mac, or Apple Watch, the confirmed value can be returned to the original payment method up to the price of the new product. Any remaining amount can be issued through an Apple Gift Card.
With an eligible monthly payment arrangement, the estimated credit can be applied directly to the new device’s purchase price. Under Apple Upgrade, a qualifying trade-in owned by the customer can reduce payments across the initial lease term. Another device cannot be traded in each time the customer exercises the lease’s upgrade option.
Values also differ between countries and can change without a product announcement. The revised dollar amounts apply to Apple’s United States program, while local market prices, available models, currencies, and trade-in partners determine estimates elsewhere.
Anyone considering an exchange should obtain a fresh estimate shortly before purchasing. Apple requires the trade-in device to arrive within the specified return period and says an online estimate is generally protected for 14 days after the customer receives the new product.
The post Apple Raises Trade-In Values for Most iPhone, iPad, Mac, & Watch Models appeared first on AppleMagazine.
While recycling is a mathematically obvious response to the finite, non-renewable nature of many resources, the economic math is often challenging. For many materials, it can be hard to compete with virgin materials on a cost basis. Fast-moving technologies like electric vehicles throw in an added complication: By the time a car is scrapped, the industry may have moved on to a different battery chemistry. That reduces the value of recycling the car’s battery back into the production chain.
Still, a study led by Xin Xiong at Nanjing University finds that in China, recycling could become the dominant source of many key materials needed to manufacture EV components over the coming decades.
The researchers set out to model how the supply of recycled materials compares to manufacturing demand in China between 2010 and 2050. It covers materials relevant to batteries across hybrid, battery-electric, and even fuel-cell vehicles (lithium, cobalt, nickel, manganese, phosphorus, sodium, sulfur, and graphite), as well as several critical elements used in electric motors (copper, neodymium, dysprosium, samarium, and cerium).
© General_4530
While recycling is a mathematically obvious response to the finite, non-renewable nature of many resources, the economic math is often challenging. For many materials, it can be hard to compete with virgin materials on a cost basis. Fast-moving technologies like electric vehicles throw in an added complication: By the time a car is scrapped, the industry may have moved on to a different battery chemistry. That reduces the value of recycling the car’s battery back into the production chain.
Still, a study led by Xin Xiong at Nanjing University finds that in China, recycling could become the dominant source of many key materials needed to manufacture EV components over the coming decades.
The researchers set out to model how the supply of recycled materials compares to manufacturing demand in China between 2010 and 2050. It covers materials relevant to batteries across hybrid, battery-electric, and even fuel-cell vehicles (lithium, cobalt, nickel, manganese, phosphorus, sodium, sulfur, and graphite), as well as several critical elements used in electric motors (copper, neodymium, dysprosium, samarium, and cerium).
© General_4530
Researchers redesigned a hard plastic so it can be broken down and rebuilt.The advance could provide a scalable route to clean energy while making plastic recycling more effective. A discarded bottle, shopping bag or car part can remain in the waste stream long after its useful life ends. Although plastic is everywhere in modern society, recycling it remains difficult because most systems require different types to be [...]
Researchers are turning toxic, centuries-old ammunition into highly efficient and cheap solar panels.Humanity has littered the sky with the refuse of fossil fuel use, releasing enough CO2 to change the planet’s climate. We are also chucking incredible sums of carbon in the form of plastics into landfills and into the environment around (and inside of) us. What if cleaning up one of these problems could also help clean up the other?
A new study led by Ruth Ebenbauer at Aarhus University experiments with this idea by upcycling discarded polystyrene into (part of) a material commonly used in carbon-capture systems.
This material is based on amines—a simple chemical group that conveniently acts like a sponge for CO2. An amine will grab CO2 molecules when exposed to them, but let go of the CO2 when heated or depressurized, leaving it ready to go again. The first “CO2 scrubbers” tried in smokestacks used amines dissolved in water to do this, but solid amines are used in all kinds of carbon-capture systems now because they require less energy. These solid materials—often made into granules similar to the activated carbon in a water filter—have high surface area and high porosity, so the amines can efficiently partner up with CO2 molecules.
© Jamesmcq24
Thousands of electric vehicles in Waymo’s autonomous robotaxi fleet may eventually give up their used batteries for a very different purpose—contributing up to hundreds of megawatt-hours of stationary energy storage to local power grids.
That prospect comes from a “strategic supply agreement” announced by Waymo and B2U Storage Solutions on June 4. B2U has been repurposing thousands of used batteries from various electric vehicles by installing them in large stationary energy storage projects. Such energy storage facilities can capture excess renewable energy during low demand periods and release such energy when local power grids are experiencing peak demand periods.
“Our business is getting the full residual value out of electric vehicle batteries after they're no longer suitable for automotive use,” Freeman Hall, CEO of B2U Storage Solution, told Ars. “Waymo puts a lot of miles on EVs and their model is expanding rapidly, and so we're just very pleased and honored to be able to work with them.”
© Awarded Goods Company
Over 20 million tons of polystyrene plastic are produced annually, yet only a small fraction is recycled worldwide. Current recycling methods consume large amounts of energy and often rely on harsh and toxic chemicals to break the strong molecular chains that make up polystyrene. One possible solution is the use of sulfur, which is an inexpensive byproduct formed when refining crude oil. Its unique chemical structure allows it to break up strong chemical chains in long plastic molecules. Despite its abundance, sulfur has very limited applications, and converting it into more usable forms tends to require a lot of heat, rendering it unused for long periods of time.
Researchers at the Dalian Institute of Chemical Physics hypothesized that sulfur could help break down polystyrene waste to form more valuable chemicals. To power this reaction, they converted sunlight into heat energy through a process called photothermal conversion. They used this heat to transform polystyrene and sulfur into valuable chemicals like 2,4-diphenylthiophene, or chemical D, and 1,3,5-triphenylbenzene, or chemical T, which are used to make semiconductors and chemical sensors.
To test this, the team mixed ground polystyrene and sulfur at a molar ratio of 1:0.5 in a glass test tube. They sealed the tube with a balloon and secured it onto an iron stand. Then, they focused sunlight onto the bottom of the tube using a curved mirror. As the mixture heated up, the yellow-white solids gradually melted and transformed into a reddish-black liquid after 2 minutes. After heating, the researchers removed the mirror and allowed the system to cool before collecting the gaseous products from the balloon and dissolving the remaining solids for further purification and analysis.
The researchers then adjusted the reaction conditions to understand what factors influenced their results. They tested the reaction without sulfur, varied the sulfur ratios from 0.2 to 0.8, and replaced elemental sulfur with other sulfur-containing compounds. They also explored adding known photothermal agents, specifically metal oxide additives, to the mixture.
To compare the difference between sunlight and artificial light, the researchers repeated the experiment indoors using a 100 Watt LED bulb and monitored temperature changes with a thermal camera. They also ran a control experiment using only polystyrene to check how sulfur affected the yield under LED light. They also tested exposure times from 1 to 6 minutes in 1-minute increments to determine how long it took to achieve the highest yields under LED. The researchers used these tests to identify which conditions were necessary for the reaction to occur and how different factors influenced its outcome.
They found that without sulfur or with alternative sulfur-containing compounds, the reaction did not produce chemical D or T under sunlight. In contrast, reactions that included sulfur successfully produced these target products, with the highest yields of 34% for D and 16% for T at a sulfur ratio of 0.5. When they added metal oxides, the chemical yields decreased to 22% and 12%, respectively, suggesting that these additives interfered with the desired reactions. In addition, when the researchers switched from sunlight to LED, the reaction yields dropped to 26% for D and 13% for T.
Next, they examined how reaction time influenced product formation. They found that yields increased gradually before reaching the maximum at 4 minutes and leveling off. They also noted that mixtures containing sulfur heated up from room temperature to 320°C (608°F), while the control setup only showed a slight temperature increase. The researchers interpreted these results as confirmation of sulfur’s dual role as a reactant and a light-to-heat converter that enables the conversion of polystyrene to useful chemicals.
Taking it a step further, the researchers tested their method on real-world polystyrene wastes, including food packaging, cup lids, and foamed plastics. They successfully produced chemicals D and T from these materials, demonstrating that their process works beyond laboratory samples.
The team concluded that their study presents a simple, fast, and solvent-free approach to converting 2 abundant waste materials into valuable chemicals using sunlight. By combining polystyrene waste and excess sulfur, the researchers offer a new pathway for sustainable polymer upcycling that uses clean energy and is broadly applicable to everyday plastics.
The post Upcycling polystyrene with sunlight and sulfur appeared first on Sciworthy.
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