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LaMa separates the gel problem from the plastic recycling stream
ExplainerOctober 9, 2026

LaMa separates the gel problem from the plastic recycling stream

Superabsorbents complicate wet processing; reported 200 kg/hour operation does not establish a route for every used diaper or construction mat.

Hereon puts breaking points into a styrene-based plastic
ExplainerOctober 9, 2026

Hereon puts breaking points into a styrene-based plastic

Bio-based content and deliberate chain cleavage change material design; fragments are not yet proof of a closed recycling loop.

Plastic pyrolysis: nameplate capacity is not operating performance
TeardownOctober 3, 2026

Plastic pyrolysis: nameplate capacity is not operating performance

Closures and underutilisation expose the gap between making an oil and running a profitable plastic-to-plastic system.

Reju’s two-minute polyester claim leaves most of the process outside the stopwatch
TeardownOctober 2, 2026

Reju’s two-minute polyester claim leaves most of the process outside the stopwatch

Fast depolymerisation is not the same as fast textile recycling; sorting, purification and future plant operation determine the result.

Toray’s recovered carbon fibre: strong filaments are not a new aircraft wing
ExplainerOctober 2, 2026

Toray’s recovered carbon fibre: strong filaments are not a new aircraft wing

Chemical resin removal can protect fibre quality, but short-fibre products and structural composites answer different engineering questions.

How molten salts turn plastic bags into fuel at 200°C
ExplainerSeptember 30, 2026

How molten salts turn plastic bags into fuel at 200°C

ORNL cracks polyethylene into gasoline-range fuel below 200°C using cheap aluminium-chloride salts. Clever chemistry — but lab-scale, polyethylene-only, and still a route to burning plastic.

MacroCycle and Meta: a recycling deal made of credits, not plastic
TeardownSeptember 27, 2026

MacroCycle and Meta: a recycling deal made of credits, not plastic

Meta will buy environmental attribute credits from MacroCycle's solvent-based PET recycling. The chemistry is novel. The plant does not exist yet, and Meta is not buying any recycled material.

Indonesia's BRIN plan: waste to syngas, carbon nanotubes and captured CO2 — how each step works
ExplainerSeptember 27, 2026

Indonesia's BRIN plan: waste to syngas, carbon nanotubes and captured CO2 — how each step works

BRIN is assembling AI sorting, gasification, plastic-to-nanotube conversion at 1,600 °C and calcium looping into one pipeline. Here is the chemistry of each stage and how much of it exists.

How sunlight turns plastic waste into hydrogen: inside Cambridge's 1 m² photoreforming panel
ExplainerSeptember 26, 2026

How sunlight turns plastic waste into hydrogen: inside Cambridge's 1 m² photoreforming panel

A semiconductor catches light, a cobalt–zirconium catalyst makes hydrogen, and dissolved plastic supplies the electrons. The first outdoor square-metre test works — modestly.

The EU wants 15% recycled plastic in new cars. Today it is 2.5%. Here is why the gap is so hard
ExplainerSeptember 25, 2026

The EU wants 15% recycled plastic in new cars. Today it is 2.5%. Here is why the gap is so hard

The End-of-Life Vehicles Regulation mandates 15% recycled plastic from 2032 and 25% from 2036. To see why that is difficult, follow a car through the shredder.

Bobine's 'electrified plastic recycling': striking numbers, no independent evidence
TeardownSeptember 23, 2026

Bobine's 'electrified plastic recycling': striking numbers, no independent evidence

The French startup claims +45% yield, −60% energy and −45% cost by heating a catalyst with induction to turn plastic waste into olefins. Every figure is self-reported, and none has a baseline.

How fungi eat industrial waste: the four tools of mycoremediation
ExplainerSeptember 23, 2026

How fungi eat industrial waste: the four tools of mycoremediation

White-rot fungi evolved to digest wood. The same enzymes attack dyes, oil and some plastics, and their cell walls soak up heavy metals. A 2026 review maps what works — and where the evidence runs thin.

The Recycling Partnership's 'Evolving Ton': excellent data, no prescription
TeardownSeptember 22, 2026

The Recycling Partnership's 'Evolving Ton': excellent data, no prescription

Cartons up 61%, mixed paper down 34%, plastics now outweigh paper in U.S. recycling. The new report is the best picture of the bin we have — and says almost nothing about what to do.

Glue and elevators: how two sizes of bubble pull 90% of microplastics out of wastewater
ExplainerSeptember 21, 2026

Glue and elevators: how two sizes of bubble pull 90% of microplastics out of wastewater

RMIT researchers upgraded a 1960s treatment step — dissolved air flotation — by pairing microbubbles with nanobubbles. Lab results top 90% microplastic removal. Here is the mechanism and the caveats.

BASF's ecovio Is Certified Home-Compostable. Two Data Sets Are Missing
TeardownSeptember 20, 2026

BASF's ecovio Is Certified Home-Compostable. Two Data Sets Are Missing

A PBAT and PLA blend with TUV OK Compost Home certification. The disintegration is tested. The barrier performance and the microplastic question are not.

California Recycles 37% of Its Carpet. That Number Took Fifteen Years
ExplainerSeptember 19, 2026

California Recycles 37% of Its Carpet. That Number Took Fifteen Years

The first carpet EPR programme in the US now runs 174 drop-off sites and recycles 78.5 million pounds a year. It is also a lesson in how slowly EPR moves.

A Catalyst That Dissolves a Plastic Designed Never to Melt
ExplainerSeptember 18, 2026

A Catalyst That Dissolves a Plastic Designed Never to Melt

pDCPD is a cross-linked thermoset with no recycling route. A ruthenium catalyst and a stirred solvent take it apart - and leave the carbon fibre intact.

Envetec Says It Can Recycle Biohazardous Medical Waste. What Is Actually Proven?
TeardownSeptember 17, 2026

Envetec Says It Can Recycle Biohazardous Medical Waste. What Is Actually Proven?

On-site shredding and disinfection that turns regulated medical waste into recyclable polymer flake. The disinfection is certified. Most of the headline numbers are not.

Terahertz Sorting: Seeing Through the Plastics That Near-Infrared Cannot
ExplainerSeptember 13, 2026

Terahertz Sorting: Seeing Through the Plastics That Near-Infrared Cannot

Near-infrared sorters are blind to black plastic and confused by multilayer film. Terahertz sensing sees through both. The physics is real; the belt speed and the detector price are not there yet.

Aduro's Hydrochemolytic Route: Water-Mediated Plastic Conversion, and the Refinery Problem It Does Not Escape
TeardownSeptember 12, 2026

Aduro's Hydrochemolytic Route: Water-Mediated Plastic Conversion, and the Refinery Problem It Does Not Escape

Aduro says its water-based chemistry converts waste plastic and heavy oil at lower temperatures than pyrolysis. Even if that holds, the output is still a feedstock that a refinery has to finish.

Kirin and JSW Put PET Depolymerisation Inside a Twin-Screw Extruder
TeardownSeptember 12, 2026

Kirin and JSW Put PET Depolymerisation Inside a Twin-Screw Extruder

Chemical recycling of PET normally means a stirred tank and several hours. Kirin and JSW have moved the reaction into a continuous extruder. If the numbers hold, the interesting part is throughput per unit of capital.

"Compostable" Is a Facility Spec, Not a Property of the Object
Myth-BustingSeptember 11, 2026

"Compostable" Is a Facility Spec, Not a Property of the Object

Certified compostable packaging is engineered to break down in a hot industrial windrow. Put it in a garden bin, a recycling bin or a landfill and it behaves like ordinary plastic — because in those conditions, it is.

ReBioCycle's PLA Loop: What a Closed Loop Means When Nobody Publishes the Yield
TeardownSeptember 11, 2026

ReBioCycle's PLA Loop: What a Closed Loop Means When Nobody Publishes the Yield

An EU project says it has closed the loop on PLA — sorting, depolymerising and repolymerising bioplastic back to virgin-grade. The chemistry is sound. The numbers that decide whether it matters are missing.

The Ocean Cleanup Says 50 Million Kilograms. Here Is What That Is a Fraction Of.
TeardownSeptember 10, 2026

The Ocean Cleanup Says 50 Million Kilograms. Here Is What That Is a Fraction Of.

The removal figure is real and independently plausible. Set against annual plastic inflow to the ocean, it represents a small fraction of a single year — and the river interceptors are the part of the programme that actually scales.

Syntetica Wants to Recycle Nylon. The Feedstock Barely Exists in Recoverable Form.
TeardownSeptember 9, 2026

Syntetica Wants to Recycle Nylon. The Feedstock Barely Exists in Recoverable Form.

Chemical depolymerisation of nylon 6 back to caprolactam is proven chemistry with decades of industrial history. The constraint has always been that most nylon in the world is blended into textiles that cannot be separated.

Acrylic Is the One Plastic That Really Does Unzip
ExplainerSeptember 6, 2026

Acrylic Is the One Plastic That Really Does Unzip

PMMA depolymerises back to its own monomer at high yield with nothing more exotic than heat. It is the clearest existing example of true chemical recycling — and the reason it stays rare is collection, not chemistry.

One Enzyme That Eats Bioplastic and Penicillin
ExplainerSeptember 5, 2026

One Enzyme That Eats Bioplastic and Penicillin

A soil-derived enzyme called LCPH1 breaks down long-chain polyester bioplastics and cleaves the penicillin beta-lactam ring. It is much better at the second job than the first, which is the detail worth sitting with.

Magnetic Microrobots for Microplastics: What the Numbers Actually Show
ExplainerSeptember 3, 2026

Magnetic Microrobots for Microplastics: What the Numbers Actually Show

A magnetically driven MXene microrobot removes most microplastic particles from water and rather less from soil. The recovery figures are real; the retrieval and leaching questions are the ones that decide whether it ever leaves the lab.

The recycling black sheep: sorting the film that optical sorters cannot see
ExplainerSeptember 1, 2026

The recycling black sheep: sorting the film that optical sorters cannot see

Flexible film and black plastic defeat the two technologies a modern sorting plant relies on. A Finnish process uses density and water instead — and a 50,000-tonne plant is being built around it.

Dirty PET goes in. An underwater glue and a stronger plastic come out.
ExplainerAugust 31, 2026

Dirty PET goes in. An underwater glue and a stronger plastic come out.

Conventional PET recycling wants clean, clear, single-stream bottles. Oak Ridge built a catalyst-free route that takes the contaminated stuff and splits it into two high-value materials instead of low-grade flake.

The plastic that evaporates at 90 °C — and rebuilds itself
ExplainerAugust 25, 2026

The plastic that evaporates at 90 °C — and rebuilds itself

A Surrey team made a polyethylene-like polymer that turns to vapour at around 90 °C and condenses back into the same solid. The mechanism is elegant. The distance between it and a recycling system is the whole story.

Can kimchi scraps become biodegradable plastic?
ExplainerAugust 24, 2026

Can kimchi scraps become biodegradable plastic?

Engineered E. coli grown on radish-trimming hydrolysate accumulated poly(3-hydroxybutyrate) to 75.6% of dry cell weight. That is a real fermentation result. It is not yet a material, a plant, or a lower-impact life cycle.

Can mixed plastic waste become the building blocks for new plastics?
ExplainerAugust 23, 2026

Can mixed plastic waste become the building blocks for new plastics?

Covestro is backing BioBTX to build a commercial plant in Delfzijl that turns hard-to-recycle plastic into benzene, toluene and xylene. The chemistry is straightforward. The evidence is a construction schedule.

How biohazardous lab plastics can become recyclable material
ExplainerAugust 21, 2026

How biohazardous lab plastics can become recyclable material

Laboratory plastic is regulated waste before it is a material. A new on-site system shreds, disinfects and dewaters it where it is generated, so what leaves the building is polymer flake rather than a hazard consignment. The step from flake to product is the one still missing.

EPS transport packaging leaves the “problematic” list — but is it circular?
TeardownAugust 20, 2026

EPS transport packaging leaves the “problematic” list — but is it circular?

On 19 August the U.S. Plastics Pact removed expanded-polystyrene transport packaging from its Problematic and Unnecessary Materials list, citing a recycling rate above 30%. That is a real result on a narrow slice of foam — and it is not permission to put your foam cup in the recycling bin.

Can aircraft waste become an aerogel?
ExplainerAugust 20, 2026

Can aircraft waste become an aerogel?

Carbon-fibre epoxy composites are among the hardest materials to recycle, because the resin will not melt back. A team at NUS skips fibre recovery entirely and turns the whole waste stream — fibre and epoxy together — into a freeze-dried porous block.

"If it is plastic, put it in the recycling bin"
Myth-BustingAugust 19, 2026

"If it is plastic, put it in the recycling bin"

Bags, wraps and mailers are plastic, carry resin codes, and look recyclable. They are also one of the most reliable ways to shut down a sorting line.

The sunlight-and-catalyst filter that attacks wastewater pollutants
ExplainerAugust 19, 2026

The sunlight-and-catalyst filter that attacks wastewater pollutants

Photocatalysis usually arrives as a powder you then have to fish back out of the water. Fixing the catalyst to a resin bed turns it into something closer to a treatment step: water in one end, oxidised organics out the other.

MIT's recyclable stretch yarn: a design win, not yet a system
TeardownAugust 16, 2026

MIT's recyclable stretch yarn: a design win, not yet a system

A polyethylene core-sheath yarn that stretches like PET-spandex and survives ten melt-and-respin cycles. The material result is real. The gap between a recyclable yarn and a recyclable garment is where almost all of the difficulty still sits.

No, plastic cannot be recycled forever
Myth-BustingAugust 12, 2026

No, plastic cannot be recycled forever

Metals and glass survive remelting largely intact. Polymers do not. Every mechanical loop shortens chains, and the recycling symbol says nothing about how many loops a package will realistically get.

Nine companies, one shared recycling line: Japan's flexible-packaging trial
TeardownAugust 10, 2026

Nine companies, one shared recycling line: Japan's flexible-packaging trial

A Ministry of the Environment-commissioned demonstration puts nine Japanese companies on a shared platform to delaminate and deink flexible packaging. It is a genuinely interesting infrastructure model. It is not yet proof of scale.

A KitKat wrapper made from soft plastics: closed loop, or mass-balance proof of concept?
TeardownAugust 8, 2026

A KitKat wrapper made from soft plastics: closed loop, or mass-balance proof of concept?

Nine and a half tonnes of pyrolysis oil, five tonnes of resin, seven million wrappers. A real supply chain ran end to end - and almost none of the numbers that would prove it works were published.

PureCycle's commercial rebound has real proof points - the economics are still on trial
TeardownAugust 7, 2026

PureCycle's commercial rebound has real proof points - the economics are still on trial

Q2 brought first branded resin deliveries, seven customer conversions and 173% revenue growth. It also brought a $142m net loss. A look at what advanced recycling has actually demonstrated, and what remains a forecast.

The triangle with a number does not mean "put me in the blue bin"
Myth-BustingAugust 5, 2026

The triangle with a number does not mean "put me in the blue bin"

The chasing arrows around a 1, 2 or 5 identify the resin. They say nothing about whether your hauler collects it, whether the sorter can capture it, or whether anyone will buy it.

Is Turning Plastic Into Hydrogen Actually Recycling?
Myth-BustingAugust 1, 2026

Is Turning Plastic Into Hydrogen Actually Recycling?

The chemistry is real. The label is doing a lot of work. If the outputs are hydrogen gas and mineral carbonate, no plastic has been recycled — something else has happened.

How Alkaline Thermal Treatment Pulls Hydrogen Out of Unsorted Plastic
ExplainerAugust 1, 2026

How Alkaline Thermal Treatment Pulls Hydrogen Out of Unsorted Plastic

A new PNAS study converts mixed PET, PE and PP into >90% pure hydrogen in one reactor — no polymer sorting, and most of the carbon never reaches the gas phase.

The Waste Stack

Independent writing on waste management systems and green engineering.

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#plastics#recycling#e-waste#landfill#wastewater#energy#food-waste#emissions#policy