Every year Europe throws away around 6.7 million tonnes of used baby diapers, plus several million more tonnes of adult incontinence products, a stream that is growing fast as the population ages, with more than 21% of Europeans now over 65. Almost all of this waste is burned or landfilled, where its synthetic components persist for centuries.

The hardest part of a diaper to recycle is also the most ingenious: the superabsorbent polymer (SAP), a lightly crosslinked sodium polyacrylate gel that absorbs up to 300 times its weight in liquid. SAP is what makes modern diapers thin, dry, and reliable, and it accounts for roughly a third of the dry mass of every diaper produced. But because its polymer chains are permanently locked together by chemical crosslinks, SAPs cannot be melted or remoulded, and conventional plastic-recycling technologies simply do not work on it. The few industrial recyclers that exist today either landfill the SAP, burn it, or “deactivate” it for low-value uses such as moisture absorbers.

We are developing a process that breaks down SAPs using only water and UV light without the need of solvents, harsh chemicals, or heat. The UV light dissolves the swollen SAPs within minutes, turning a sticky, contaminated waste into a clean, reusable raw material. We are also working on ways to turn this recycled material into genuinely valuable products (e.g., adhesives, thickeners, and coatings) that today are still made from petroleum.

The timing matters. Italy is investing €110 million to build 15 new diaper-recycling plants under its national recovery plan, and the EU is tightening producer-responsibility rules for hygiene products. By 2030, Europe will have the infrastructure to collect and separate diaper waste, but no good answer for what to do with the SAPs it recovers. At DegSUP, we want to be that answer.