'Chemical recycling': 15-minute reaction turns old clothes into useful molecules | Hacker News Reader

'Chemical recycling': 15-minute reaction turns old clothes into useful molecules

nature.com

5 pointsgnabgib2 comments

> The researchers instead turned to chemical recycling to break down some synthetic components of fabrics into reusable building blocks. They used a chemical reaction called microwave-assisted glycolysis, which can break up large chains of molecules — polymers — into smaller units, with the help of heat and a catalyst. They used this to process fabrics with different compositions, including 100% polyester and 50/50 polycotton, which is made up of polyester and cotton.

> For pure polyester fabric, the reaction converted 90% of the polyester into a molecule called BHET, which can be directly recycled to create more polyester textiles. The researchers found that the reaction didn’t affect cotton, so in polyester–cotton fabrics, it was possible to both break down the polyester and recover the cotton. Crucially, the team was able to optimise the reaction conditions so that the process took just 15 minutes, making it extremely cost-effective.

1. Flash heating plastic yields Hydrogen and Graphene; "Synthesis of Clean Hydrogen Gas from Waste Plastic at Zero Net Cost" (2023) https://onlinelibrary.wiley.com/doi/10.1002/adma.202306763 https://news.ycombinator.com/item?id=37886982

2. This produces microwave (and THz) with Copper as the dielectric; though I don't think they were trying to make a microwave oven; "Pulsed THz radiation under ultrafast optical discharge of vacuum photodiode" https://news.ycombinator.com/item?id=40858955

3. Metasurface arrays could probably also waste less energy on microwaving clothing and textiles in order to recycle.

4. Are SPPs distinct from Cherenkov radiation, and photon-electron-phonon vorticity?

From "Electrons turn piece of wire into laser-like light source" https://news.ycombinator.com/item?id=33493885 :

Surface plasmon polaritons : https://en.wikipedia.org/wiki/Surface_plasmon_polaritons :

> [...] SPPs enable subwavelength optics in microscopy and photolithography beyond the diffraction limit. SPPs also enable the first steady-state micro-mechanical measurement of a fundamental property of light itself: the momentum of a photon in a dielectric medium. Other applications are photonic data storage, light generation, and bio-photonics.

But that's IR and visible light EM, not microwave EM.

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