Technische Universität Berlin has developed a new catalytic process to fully break down silicone waste.

Common items like the silicone spatula in your mixing bowl, the leak-proof seal in your travel mug, and the soft pacifier that keeps a toddler quiet all share a hidden downside. All are immortal.

Silicones resist heat, water, and chemical breakdown. Hence, throwing the waste away usually means sending it to a landfill or an incinerator. Until now, a closed-loop recycling has been a tough task, chemically. TU Berlin says they have found a way forward after years of research.

Led by Professor Dr. Martin Oestreich, the team developed a catalytic process that breaks down silicon-oxygen polymers back into their original, high-value building block: dimethyldichlorosilane. 

The study details a strategy that gives up to a 99% recovery rate from regular items like muffin pans and baby bottles. 

“Our success is proof that basic research can eventually pay off in very specific applications that no one had previously thought of,” said Oestreich. “We’ve been conducting research on silylium ions for 15 years, and it’s only in the last five years or so that we have suddenly identified the recycling of silicones as a key application for this research.”

To make fresh silicone from scratch, manufacturers first extract raw silicon from quartz sand inside electric arc furnaces fired at extreme temperatures. It is a massive, energy-intensive undertaking. Once formed, the resulting silicon-oxygen bonds behave like molecular superglue. Breaking them requires immense energy or unprecedented catalytic precision.

Oestreich’s team spent 15 years studying the silylium ions (positively charged silicon ions) before realizing the hidden potential for waste management.

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