Zirconium-Catalyzed Retrovulcanization and Retropolymerization Reactions for the Recycling of Rubber and Polyolefin Waste

Converting the polymer waste that is generated everyday into a usable feedstock for chemical processes will be a key technology for the transition of our society into a sustainable future.

Here, the “chemical recycling” of vulcanized rubber (old tires) and polyolefin plastics waste (eg. polyethylene bags) represents a longstanding challenge with high ecological, economic and social impact. Currently, the best way of disposal still is combustion, which at least allows a partial recovery in form of energy.

In contrast, the available methods of recycling are energy-intensive and lead to lower-quality products that cannot replace fossile feedstocks.In this project, I now propose the realization of catalytic “retrovulcanization” and “retropolymerization” processes for the recycling of polyolefin and rubber waste on a laboratory scale.

This molecular approach is based on zirconium-catalyzed C-S and C-C cleavage reactions recently developed in my group that will allow a selective breakup of the vulcanizate and polyolefin networks, respectively.

The project is divided into five work packages, comprising the optimization of the retrovulcanization and retropolymerization reactions as well as the required catalysts.

Finally, the realization of sustainable conditions and the combination both approaches will be undertaken, which will allow the highly efficient conversion of vulcanized rubber and polyolefin waste back into base chemicals.