Tag Archives: recycling

E-Waste Challenges: A Guide to Recycling Old Mobile Phones and Computers

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I The development of electronics that support our daily lives requires significant time, resources, and fossil fuels. The journey from mining rare earth materials to processing, manufacturing, and shipping creates immense waste. The innovations in engineering and logistics that allow consumers to buy new mobile phones annually contribute to this issue.

According to the latest Global E-Waste Monitor, the world generates 62 million tons of electronic waste each year, with projections estimating e-waste emissions could reach 82 million tons by 2030. Australia contributes 580,000 tonnes of this annually. Factors like planned obsolescence, technological advancements, and device failures are expected to escalate this figure.

It’s estimated that 23 million mobile phones are unused and gathering dust in drawers across Australia, some of which are truly non-functional. Research indicates that the average Australian produces around 22kg of e-waste annually, nearly three times the global average, according to recent studies from the Productivity Commission.

“It’s the fastest growing waste stream, but it’s also the most valuable,” states Anne Stonier from the Australia New Zealand Recycling Platform (ANZRP). “Electronics also contain substantial amounts of hard plastics. Recycling can help ensure these materials are managed responsibly, contributing to a more circular economy.”

Wondering where to dispose of your old phone? Concerned about keeping your sensitive data safe? Here are some things to consider when recycling your old device.

Discover Local Recycling Programs

Recycling e-waste is more complex than merely putting it in the yellow bin. The first step is to identify local options available to you. For instance, local councils often have designated collection points and e-waste recycling programs. The locations may vary, and e-waste is banned from landfills in Victoria, South Australia, and Western Australia.

Additionally, several major retailers run recycling initiatives. Officeworks, for example, collects and recycles batteries, computer accessories, printer cartridges, and mobile phones. Their drop-off days apply to many other electronic products as well. Bunnings also offers collection bins for batteries and larger electronics like TVs, computers, and printers. The Mobile Muster program, run by the Australian telecommunications sector, collects a variety of devices, including mobile phones and streaming devices.

Many manufacturers also have take-back programs, allowing customers to trade in their old devices for discounts or credits on future purchases. If you’re thinking of upgrading, explore the options available to you.

Some charities accept donations of electronic devices, such as DV Safe Phone and Reconnection Project, which refurbish used devices and distribute them to those in need.

Disposing of Devices that Store Personal Information

Devices, whether it be a smartwatch tracking your daily runs or a tablet previously used for work, often store sensitive personal information.

Before disposing of electronic items, remember to back up or transfer any important files to another device or storage option (like an external hard drive or cloud service) and remove any identifying marks or stickers from the device.

What happens next depends on the device. For most smartphones, tablets, and smart devices, a factory reset will suffice. For computers, laptops, hard drives, and USBs, reformatting the drive and restoring factory settings should be enough. Don’t forget that fax machines, printers, and scanners may retain copies of printed documents, so perform a factory reset on those as well.

Finally, ensure you unpair your old device from any remaining computers or gadgets.

If your device is so outdated that it won’t power on and can’t connect to your computer, there’s not much you can do. Just make sure to remove any external memory cards before recycling.

What If My Device Contains Highly Sensitive Information?

Physically destroying a device, like drilling holes in a hard drive, is usually ineffective and counterproductive to the recycling process. It may also pose dangers, especially with devices featuring non-removable batteries, which could cause explosions and health hazards.

For devices containing highly confidential information you want to ensure is irretrievable, consider using data sanitization software to reformat your device and encrypt the hard drive. Secure data erasure services are also available, though their offerings and prices can differ widely. Some companies may provide free data destruction for donated hard drives so they can be repurposed, while other services are geared toward larger enterprises.

Some specialized recyclers also offer data destruction services, Stonier mentioned. “If you’re worried about your information falling into the wrong hands, it’s best to wipe it,” she advises. “Better safe than sorry.”

What Happens If I Don’t Take Any Action?

The severity of potential threats can vary. A hard drive filled solely with family photos poses less risk than one containing sensitive financial data. For the majority, it’s improbable they would be specifically targeted unless there’s a clear motive or pre-existing vulnerability.

Criminal activity is often opportunistic, and taking basic precautions can prevent future issues and anxieties.

Source: www.theguardian.com

Key Concepts for Improving Plastic Recycling

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“To enhance both plastic recycling and reuse, brands should utilize similar packaging for products within the same category.”

Elaine Knox

Since its inception in 1899, the US National Biscuit Company has utilized packaging as a marketing strategy by wrapping Uneda soda crackers in wax paper inside cardboard boxes. Over the decades, businesses have increasingly turned to plastics, making unique packaging a key component for establishing brand identity.

However, the fragile economics of plastic recycling are deteriorating, compounded by the complexity introduced by varying pigments, materials, and more. Currently, only 10% of plastic packaging is recycled globally. In contrast, reusable packaging remains in a niche market.

There are effective and straightforward methods to enhance both the recycling and reuse of plastics, such as having brands adopt similar packaging for products in the same category.

Initially, prioritize recycling. Despite decades of consumer awareness and infrastructure investments, managing various plastic types into specific subcategories remains prohibitively costly. Eliminating pigments and sorting by color is expensive, leading to many plastic varieties being downcycled into gray pipes and construction materials. The supply chain is inconsistent and fragmented, with virgin plastics remaining cheaper, resulting in a lack of reliable buyers for most recycled plastics.

Standardization could significantly improve this situation. If product categories adopt uniform guidelines for plastic types, colors, labels, and adhesives, recyclers could potentially recover much more material at a reduced cost. This would enhance economic viability for recycling and facilitate the vision of producing new bottles from old ones.

The case for standardized reuse systems is equally compelling. Presently, many brands experimenting with reuse employ different containers, necessitating individual return points coupled with specialized cleaning equipment and quality assurance checks, which adds costs and complexity while reducing convenience. Systems based on standardized packaging and shared infrastructure could capture 40% of the market through a more consolidated approach, as noted by the Ellen MacArthur Foundation.

While standardized packaging might seem anti-capitalistic to some, many brands already produce similar packaging, such as milk jugs in the UK and toothpaste tubes in various countries. Standardization does not imply that all products must look identical. Brands can still employ unique labels, washable inks, embossing, and other distinguishing features. They can also maintain their own shapes and sizes.

It’s undoubtedly challenging to envision competitors like Procter & Gamble and Unilever willingly agreeing to package shampoo in identical bottles. However, with billions lost annually due to single-use plastics, where data ends up incinerated or in landfills, research increasingly highlights health risks associated with unstudied chemicals in plastics. Brands may find it challenging to safeguard their interests. Legally, it could be argued that the harm stemming from customized packaging outweighs the advantages of standardized containers.

More brands might soon have little choice. Regulatory frameworks are evolving in Europe and other regions, focusing on reuse targets and increased recycled content. Standardized packaging offers brands a pathway to meet these objectives while minimizing complexity and cost increases.

Undoubtedly, like-colored shampoo bottles won’t solve all issues, but such changes are becoming increasingly sound from a business perspective. Without them, achieving truly circular packaging remains a distant goal.

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Source: www.newscientist.com

Water-Soluble 3D Printed Electronics for Fast Recycling

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Prototype electronics can be made from polymers that dissolve in water, facilitating recycling.

ZEYU YAN/University of Maryland

Devices like Bluetooth speakers can be 3D printed using water-soluble materials in just a few hours. This innovation enables rapid prototyping, easier recycling of electronic waste, and encourages more sustainable manufacturing practices for consumer electronics.

Researchers have successfully created technology that can dissolve, including printed circuit boards that house essential components and wiring for modern electronics. Each year, hundreds of millions of printed circuit boards are produced for military aircraft, automobiles, medical devices, smartphones, and inexpensive toys. Yet, globally, only a fraction of these devices are recycled through labor-intensive methods, often involving shredding to reclaim usable materials, according to Huaishu Peng from the University of Maryland.

Peng and his team crafted a 3D printed circuit board with polyvinyl alcohol, a polymer that dissolves in water. They filled the circuit board’s channels with liquid gallium-indium metal alloys for wiring, and manually attached electronic components. After sealing the circuit with a polymer adhesive, the device was dried for an hour at 60 °C.

This method enabled researchers to assemble functioning prototypes of a Bluetooth speaker, a fidget toy, and an electronic gripper with three fingers. A small amount of water does not immediately damage these devices, but after soaking for 36 hours at a room temperature of 22°C, they dissolve.

The researchers could then easily retrieve most electronic components and liquid metals, which accumulated as small beads. The evaporation of water also allowed them to recover 99% of the dissolved polyvinyl alcohol.

Soluble circuit boards are particularly beneficial for designers who aim to quickly test and validate electronic prototypes, as recycling traditional printed circuit boards presents significant challenges. As noted by Jasmine Lu from the University of Chicago, Illinois, in her study on circuit board reuse, “Printed circuit boards are a major source of e-waste during the prototyping of electronic devices.”

A 2022 United Nations Report regarding e-waste revealed that Asia generated 600,000 tons of discarded circuit boards but managed to recycle only 17%. In contrast, Europe and North America produced 300,000 tons of printed circuit boards, achieving a recycling rate of 61% in Europe and 44% in North America.

What sets this approach apart is that virtually anyone with a 3D printer can implement this dissolvable electronics methodology, making it more accessible compared to other sustainable electronics initiatives, according to Lu. For practical use, Peng suggests that the devices can be safeguarded with a temporary waterproof casing.

Nonetheless, due to the inherent fragility of these circuit boards, Lu indicates that soluble electronics are currently more suited for rapid prototyping rather than mass production of finished electronic goods.

Peng and his colleagues have not dismissed the idea of mass production. They are reaching out to circuit board manufacturers to explore the possibilities. For now, Peng aims to utilize this technology to enable university students to rapidly prototype and reuse designs.

“Typically, you would need to outsource circuit board production to a factory, which could take weeks for manufacturing and shipping,” he explains. “You can design something here, print it in under 30 minutes, and if it doesn’t work, simply dissolve it in water and try again.”

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Source: www.newscientist.com

Recycling: A Key Strategy to Reduce Harmful Styrofoam Packaging

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As legislators tackle hard-to-recycle plastics and foams, packaging firms in California are unveiling innovative transport coolers crafted from woven fibers, revolutionizing the way temperature-sensitive products like pharmaceuticals and laboratory reagents are shipped globally.

The launch of new “recycled” containers made from recyclable paper and fibers aligns with the “Expanded Producer Responsibility” (EPR) Act, pushing the U.S. towards a more sustainable product landscape.

At least 33 states have enacted EPR laws aimed at reducing the use of plastics, styrofoam, and other contaminating materials by holding businesses accountable for their lifecycle and transferring disposal costs to producers.

Over 80 million tons of packaging waste are discarded annually in the U.S., with only around half being recycled, and a mere 9% of plastic packaging finding its way back into the recycling stream, according to Product Stewardship Research Institute.

The EPR Act seeks to minimize landfill waste, boost recycling rates, and mitigate the environmental harm caused by non-recyclable materials, prompting businesses to navigate increasingly stringent packaging regulations.

Recently, seven states have adopted the EPR Act, specifically targeting packaging materials in California, Washington, New Jersey, Minnesota, Colorado, Oregon, and Maine.

“As temperatures rise globally, the need for safe delivery options becomes crucial,” stated Catherine Telloch, CEO of the nonprofit Chicago Environmentalist. “Transitioning to fully recyclable items is fantastic, as it allows for continuous cleaning and reuse, positively impacting the environment.”

Recycling staff

Last month, Container Consulting Services from Gilroy, California, announced the launch of recyclable personnel made from paper and textiles. These containers are validated by a third party to comply with ISTA Thermal and ISTA Transit Standards, meeting essential qualifications for shipping medicines.

Other companies are manufacturing comparable eco-friendly transport coolers, but according to CCS, their product utilizes unique technology that maintains the necessary cold, matching the performance of plastic options. Their patented design features open-cell woven or nonwoven fibers that range from 1.5 to 3 inches thick, sandwiched between two interconnected fiber walls, offering insulation that effectively resists heat, akin to expanding polyethylene.

CCS claims recyclers can maintain contents at cool temperatures for over 100 hours, making them suitable for long-haul and international shipments. Upon arrival, these containers can be converted into other paper products through curbside recycling.

Telloch expressed that recyclers present a viable alternative to polystyrene. A few months prior, she received a shipment of temperature-sensitive medicine that was packed in styrofoam.

“I didn’t want that; it wasn’t good,” Telloch remarked. “If they could utilize a recyclable option instead, that would be fantastic.”

The potential impact of reusable transport coolers is significant, studies indicate. Materials such as polystyrene and polyethylene commonly used in coolers are non-biodegradable and pose threats to both human and animal health. Styrene carcinogens are released during production and usage. These lightweight materials tend to break apart and contaminate the environment as wildlife ingest microplastics. Plastic foam made with these compounds can persist in nature for thousands of years, as noted by the United Nations Environment Programme.

“Polystyrene foam is particularly harmful,” said Janet Domenitz, executive director of the Massachusetts Student Public Interest Research Group, a student advocacy organization focused on public health and environmental protection. “It’s much lighter than other plastics, making it easy for wind to carry it into landfills and the environment.”

Proponents of polystyrene argue that the material is cost-effective since its lightweight nature requires less energy and water compared to paper or fiber alternatives. The plastics industry organization did not respond to requests for comment.

Nevertheless, numerous lawmakers across the U.S. are contemplating bans on polystyrene products. In March, Senator Chris Van Hollen and Rep. Lloyd Doggett introduced the Bubble Farewell Act, which aims to prohibit the sale and distribution of polystyrene products by 2028. Additionally, California enacted a law in 2022 mandating plastics and packaging companies to minimize single-use plastics, although its implementation remains pending amid uncertain circumstances.

Globally, there is a push to eliminate plastic foam packaging, with numerous countries like Canada, Germany, and Zimbabwe having banned or restricted styrofoam, particularly in food services and packaging.

Julie Etter Simpson, co-owner of CCS, emphasized that Recycoolers are developed to align with these evolving laws.

“Product versatility is key to our commitment to environmental responsibility,” she stated.

Yaniv Abitan, managing director of Insulpack Group, an international cold package distribution company, remarked that his company has evaluated the recycling personnel and believes it will drive significant environmental initiatives as the industry shifts away from single-use plastics and EPS forms.

“We recognize the urgent need for eco-friendly alternatives that do not compromise on performance,” Avitan concluded. “Recyclers symbolize the direction the industry is headed towards for domestic and international cold chain transportation.”

Source: www.nbcnews.com

Plastic evaporation method could enable infinite recycling of bags and bottles

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Polyethylene plastic bags are difficult to recycle

Robert Sanders/University of California, Berkeley

Plastic bottles and bags can be evaporated into their chemical components and turned into new plastic that has all the properties of virgin material. Though there are still hurdles to overcome, this new process is a big step towards a truly circular economy for plastics.

About 5 billion tons of plastic Plastics have been heading to landfills since the 1950s, but recycling efforts only address 9% of what we produce. With current technology, plastics degrade every time they are recycled, and after just a few rounds of this process they end up in landfills.

John Hartwig Dr. Hartz and his colleagues at the University of California, Berkeley, had previously developed a process to break down waste plastic into its component parts, but it relied on expensive metal catalysts — iridium, ruthenium and palladium — that were lost in the process and couldn't be recovered. Hartwig says the technology is “good for academic papers and demonstrations, but it's not anywhere near what could be considered industrialized.”

Now his team has found an improved process that works for both polyethylene, the raw material in most plastic bags, and polypropylene, used to make stiffer objects. The process uses only a catalyst that's so common it's considered “earthy” in nature, Hartwig says.

Plastics are made up of large molecules called polymers, which are in turn made up of smaller units called monomers. The catalyst breaks the chemical bonds in the polymers, turning them into gaseous monomers from which new plastic can be made with all the properties of virgin, non-recycled material.

In their experiments, the team used two catalysts — sodium on aluminum oxide and tungsten oxide on silica — to convert a mixture of polyethylene and polypropylene into the monomers propylene and isobutylene with nearly 90 percent efficiency.

Benjamin Ward A researcher from Cardiff University in the UK, who was not involved in the study, says thousands of additives, including dyes, flame retardants and plasticizers, make plastics difficult to recycle. These additives can make up a third of the finished product and can contaminate the end product after it's recycled. “Additives delay landfilling. They delay the environmental problem. But they don't prevent it entirely,” he says.

Ward believes the new process solves the additive problem by stripping the material down to its constituent gaseous monomers, which also removes the additives.

Hartwig cautions that there are still many hurdles to overcome, and that the process has only been tested in the presence of a small number of common additives. “There will be additives that poison the catalyst or inhibit it,” he says. “We need to find a way to isolate them, which may not be optimal, or we need to find a different catalyst structure or composition that is more resistant to those additives. It's definitely a challenge.”

Cressida Bowyer Researchers from the University of Portsmouth in the UK say that even if there are processes in place that can break down waste plastic into its component parts and tolerate additives, further concerns remain: “The toxicity and disposal of the recycled end product.” [such as catalysts and additives] “These must be taken into account, and may outweigh the benefits of recycling technologies,” she says. “Recycling should not be seen as a solution or justification for maintaining or increasing the production of single-use or unnecessary plastics and continuing the current prevalent 'take, make and throw away' culture.”

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Source: www.newscientist.com

Effective Recycling Techniques to Reduce Plastic Waste from Ending up in Landfills

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Andriy Onufriyenko/Getty Images

In 1980, Disney World in Orlando, Florida, began developing a new method of generating electricity for its theme parks that would reduce the use of increasingly expensive oil. The solid waste-to-energy conversion plant took garbage, including plastics, and converted it into flammable gas using a method called pyrolysis. It opened in 1982 but closed a year later due to high operating costs.

Today, environmentalists cite the Disney story that shatters the reputation of a series of new technologies collectively known as advanced recycling, which takes plastic waste and turns it back into brand new plastic.

Their argument is dishonest. The failure of the Disney plant had more to do with the subsequent drop in oil prices than with any technical or environmental issues. Pyrolysis has improved significantly since the 1980s. In any case, Disney’s factory is designed to produce fuel, not classified as advanced recycling.

Advanced recycling is rapidly innovating with the potential to help solve the global plastics crisis, as reported in our feature “A surprising new technology that could recycle all plastics forever.” It has the potential to capture millions of tonnes of waste plastic and turn it back into a clean, fresh state by breaking it down into its molecular components. The goal is a circular economy that eliminates the need to make “virgin” plastic from oil.

It’s not a panacea. These factories produce toxic waste, have problems with their energy use, and perpetuate traditional plastics ahead of newer, greener alternatives. Campaigners are right to argue that it would be better to do away with plastic altogether. However, given practical considerations, they are not going away anytime soon, and most advanced recycling technologies are better for the environment than their alternatives.

There should be serious discussion about advanced recycling, especially whether it should be incorporated into future global treaties on plastic pollution. Make sure it’s based on fact and not a Disney story.

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Source: www.newscientist.com

Innovative technology revolutionizes recycling of all plastics indefinitely

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Satakorn Skontakayonkul/Alamy

I spend countless hours sifting through plastic pieces in my kitchen to determine if they can be recycled. If you have them, put them in a bag along with glass, cans, cardboard, and paper. If not, or if you’re not confident, put it in a plastic bag (not recyclable) and shove it in the cupboard under the stairs. I plan to drop it off in a non-recyclable plastic bin at my local supermarket. But the road to the landfill is paved with good intentions. Sometimes I get frustrated and throw it away.

I don’t know if my relentless culling will actually make any difference. We hope that what is recyclable will eventually be recycled. As for the others, which make up about half of my plastic waste, I don’t know their fate. I think there’s a reason it’s called “non-recyclable.”

We hope that you won’t have to waste your precious time on this kind of waste prioritization any time soon. A series of “advanced recycling” technologies are gradually being rolled out that promise to convert all kinds of used plastics into something very useful: plastic. The goal is to create a circular economy for this material by eliminating the need to make virgin plastic from crude oil and simply endlessly recycling what we already have. Plastic, once demonized as the scourge of modern society, could once again be great.

There are many things you can use. Since the 1950s, we have produced over 10 billion tons of her.

Source: www.newscientist.com

Why recycling may not always be the most effective solution for combating climate change

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Recycling is not a silver bullet to stop climate destruction. Far from it. Potential Impact – Savings of approximately 11 gigatons of carbon dioxide (CO2) over 30 years. Even if the world recycled more than 80 percent of its municipal waste, that amount would be overshadowed by the greenhouse gases emitted by fossil fuels and industry – a staggering 36.8 gigatons in 2022 alone.

In the UK, it is estimated that recycling 18 million tons of CO2 annually. This is equivalent to removing five million cars from the road. While promising, it is only a very small fraction of the emissions generated by fossil fuels and industry each year, which are about 200 times greater than those from agriculture and the global fashion industry.

These numbers may be discouraging, but what can an individual do to help?

Reduce, Reuse, Recycle

First and foremost, do not give up on recycling. It is a simple way to reduce landfill waste and slow down the depletion of the earth’s resources.

To put into perspective the impact of recycling, dividing the 18 million tonnes by the UK’s population of 67 million, the average Briton is saving about 269kg of CO2 per year through recycling.

According to DEFRA, Britons recycled 44% of household waste in 2021. By recycling 100% of household waste, an individual could save up to 610kg per year.

If you truly want to make a difference, focus on making sustainable choices early on in the consumption process. Opt for loose fruits and vegetables, solid detergents, repair and reuse old clothes, and most importantly, buy less.

Emphasize the Reduce and Reuse aspects of the 3R mantra and resort to recycling only when other options are exhausted.

Let’s Start With One Thing

If you feel overwhelmed, start by making one sustainable change at a time. For example, by using a reusable water bottle instead of plastic ones, you can save 20kg of CO2 per year.

A review of thousands of studies worldwide suggests that changes like taking fewer long-haul flights, using public transport, and improving home energy efficiency are significant in reducing household carbon footprints.

While recycling alone may not be the solution to climate change, it is a step in the right direction. Each individual has the power to make a positive impact.

This article addresses the question posed by Jensen Pitts via email: “Can recycling really make a difference?”

If you have any questions, please email us at: questions@sciencefocus.com or reach out to us via Facebook, Twitter, or Instagram (don’t forget to include your name and location).

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Source: www.sciencefocus.com

Overcoming Plastic Pollution: Recycling Alone Is Not Enough

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I recently came across a photo that I can only describe as “post-apocalyptic cute.” It depicted a small, beady-eyed, purple hermit crab with its fragile abdomen neatly tucked within a bright red object.

This “shell” provided the small crustacean with armor that kept it perfectly balanced and easily manipulated. However, it was not a traditional seashell, but rather a discarded plastic bottle cap. This image is a moving depiction of the serious global problem of plastic pollution we currently face.

Hermit crabs scavenge for things from the ocean floor and use them for protection. This habit of finding their home and carrying it on their backs earned them their delightful name.

However, instead of finding beautiful coiled snail shells to nestle in, many hermit crabs today pick up pieces of trash that we throw away and hide inside them.

A group of Polish researchers based at Warsaw University and Poznań University conducted an “Internet Ecology Study,” during which they scoured social media for photos of hermit crabs decorated with human trash. They found 386 photos in total from every tropical coast in the world.

According to the Environmental Investigation Agency (EIA) 2021 report, plastic production has increased by an almost unimaginable 18,300% in 65 years, leading to a current oversupply of plastic waste that we are struggling to dispose of responsibly.

Recycling may seem like an obvious solution, but as of 2015, only 9% of generated plastic waste was being recycled, according to a major study on the fate of plastic.

Examples of plastic reuse

Mark Miodnik, Professor of Materials and Society at University College London, has stated that reusing is the best solution to the plastic waste problem. One major effort in bringing reuse into the mainstream is Loop, which operates a “global reverse supply chain” in partnership with major brands, collecting used packaging from consumers and retailers through a deposit return scheme.

Despite the devastating increase in plastic production, there is hope for significant change in the near future. A commitment to a binding treaty to end plastic pollution has already been signed by 175 countries, setting the stage for a pivotal year in rewriting the plastic waste rulebook.

In the meantime, reusing as much of the materials we already have in abundance can help alleviate the plastic waste problem. As a lead researcher on hermit crab research in Poland, Zusanna Jagiello notes that the animals are simply taking advantage of what’s available to them.

Source: www.sciencefocus.com

Revolutionary New Technology Accelerates Diaper Recycling by 200 Times

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The superabsorber becomes a liquid under ultraviolet light after absorbing enough water. It can then be reused. Credit: Ken Pekarsky, KIT

Water and UV light effectively and quickly break down the cross-linked polymers in diaper liners without the use of any chemicals. This process allows recycled plastic molecules to be reused for a variety of uses.

Superabsorbent materials such as sodium polyacrylate are important components of a variety of hygiene and medical products, including diapers, bandages, and dressings. These cross-linked polymers are typically insoluble in water, although they are known for their high absorbency. Recycling them traditionally required the use of strong acids.

It will not melt at high temperatures, it will only deteriorate. However, the acid “breaks” the chains and stabilizes the polymer after about 16 hours at 80 degrees. Celsius Therefore, recycling is now possible. Because this process is complex and expensive, superabsorbents are rarely recycled. Approximately 2 million tons of this waste is thrown away or incinerated each year.

Turns into liquid in 5 minutes instead of 16 hours

Researchers from KIT’s Institute of Biochemical Systems, Institute of Biointerfaces, and Institute of Chemical Technology and Polymer Chemistry have discovered that crosslinked sodium polyacrylate polymers degrade under ultraviolet light after uptake of water. .

“The chains that connect the polymers are broken by light, and they are so loose that they swim underwater and turn into liquid fibers,” explains Pavel Levkin, a professor at the Institute of Biochemical Systems. For the study, researchers cut liners from traditional diapers, wetted them with water and exposed them to a 1000 W lamp. After 5 minutes, the solid material turned into a liquid and fell into the collector. “This method using ultraviolet light is about 200 times faster than using acids,” Revkin says.

Recycled polymers can be used in a variety of ways

The team then used known processes to convert the liquid into new adhesives and dyes. “The observation that this substance is soluble and processable was very important. It could probably be turned into many other products,” explains the scientist.

In the test, the researchers used clean diapers. However, it is also possible to separate superabsorbents from used diapers. “Therefore, there is no reason why a near-realistic use should not be possible,” Revkin says. By using solar power, you can optimize recycling methods that are cost-effective and environmentally friendly. “We have discovered a promising strategy to recycle superabsorbents, which significantly reduces environmental pollution and contributes to a more sustainable use of polymers.”

Reference: “From diapers to thickeners and pressure-sensitive adhesives: recycling superabsorbents by UV degradation” by Shuai Li, Johannes M. Scheiger, Zhenwu Wang, Birgit Huber, Maxi Hoffmann, Manfred Wilhelm, Pavel A. Levkin , September 7, 2023 ACS Applied Materials & Interfaces.
DOI: 10.1021/acsami.3c06999

Source: scitechdaily.com