Check the label on whatever you're wearing right now. Chances are it says something like "60% cotton, 40% polyester." That innocent blend is one of the biggest headaches in the entire waste industry — because until now, nobody could figure out how to pull those fibres apart and recycle them properly.
Researchers at Avantium and the University of Amsterdam have changed that. Their breakthrough, published in Nature Communications, uses concentrated hydrochloric acid at room temperature to dissolve the cotton in polycotton fabrics, converting it into glucose while leaving the polyester completely intact. The cotton-derived glucose becomes feedstock for bio-based plastics and chemicals. The polyester gets recycled into virgin-quality fibre, ready to become new clothes.
It sounds deceptively simple. It isn't.
Why mixed fabrics have been so hard to crack
The global textile industry produces around 132 million tons of fibre every year, and that figure is climbing toward 149 million tons by 2030. Yet less than one per cent of clothing gets properly recycled. The rest is downcycled into insulation and stuffing, incinerated, or buried in landfill.
The core problem is that cotton and polyester — which together dominate the clothing market — behave completely differently at a molecular level. Cotton is a natural cellulose; polyester is a synthetic polymer. Most recycling processes that work on one destroy the other. Mechanical recycling shreds fibres into shorter, weaker strands. Chemical recycling has typically required high temperatures and harsh conditions that degrade both materials.
What the Amsterdam team discovered is that superconcentrated hydrochloric acid — 43% by weight — at room temperature selectively breaks down cotton cellulose into glucose without touching the polyester. PhD student Nienke Leenders, first author of the study, tested the process on actual post-consumer clothing at Avantium's pilot plant in Delfzijl, Netherlands, achieving 75% cotton recovery and 78% polyester recovery.
Professor Gert-Jan Gruter, who leads the research group and serves as Avantium's Chief Technology Officer, called it "a crucial advancement towards achieving a circular economy," adding that Avantium is committed to "broadening its application to address the global textile waste problem."
From lab to laundry basket
The technology is already being tested at pilot scale, and Avantium plans to advance to a demonstration plant this year, with commercial operations handling 100,000 tons of textile waste annually by the end of the decade.
The timing is no accident. Extended Producer Responsibility regulations, which require fashion brands to pay for the waste their products generate, took effect in the Netherlands in January 2025. The EU made textiles EPR mandatory across all member states last October, with full compliance required by 2028. The UK is expected to follow within five years. These regulations are turning textile recycling from an environmental nice-to-have into a financial necessity.
A Scottish opportunity
Scotland may be particularly well placed to benefit. The country has a proud textile heritage — from Harris Tweed, hand-woven on treadle looms in the Outer Hebrides, to Johnstons of Elgin's centuries-old cashmere operations and innovative mills like Prickly Thistle, Scotland's only B Corp-certified textiles manufacturer.
Zero Waste Scotland has already invested £2 million through its Circular Textiles Fund to reduce the environmental impact of textiles, and the Scottish Government's Circular Economy and Waste Route Map targets net zero through exactly this kind of circular thinking. Clothes account for just four per cent of Scotland's waste by weight, but a striking 32 per cent of the carbon impact of household waste.
With existing textile expertise, government backing, and a clear policy direction, Scotland could be a natural home for recycling capacity — turning the country's weaving heritage into a circular economy future.
The bigger picture
For now, the breakthrough belongs to a pilot plant in the Netherlands and a paper in Nature Communications. But if Avantium's commercial ambitions hold, the polycotton blend on your label could go from recycling nightmare to recycling success story within a decade. And that label might just read "made from recycled fibres" — without any asterisks.
