Towards the Circular Economy: Converting Aromatic Plastic Waste Back to Arenes over a Ru/Nb₂O₅ Catalyst

Abstract

The upgrading of plastic waste is one of the grand challenges for the 21^st century owing to its disruptive impact on the environment. Here, we show the first example of the upgrading of various aromatic plastic wastes with C-O and/or C-C linkages to arenes (75-85 % yield) via catalytic hydrogenolysis over a Ru/Nb₂ O₅ catalyst. This catalyst not only allows the selective conversion of single-component aromatic plastic, and more importantly, enables the simultaneous conversion of a mixture of aromatic plastic to arenes. The excellent performance is attributed to unique features including: (1) the small sized Ru clusters on Nb₂ O₅ , which prevent the adsorption of aromatic ring and its hydrogenation; (2) the strong oxygen affinity of NbO_x species for C-O bond activation and Brønsted acid sites for C-C bond activation. This study offers a catalytic path to integrate aromatic plastic waste back into the supply chain of plastic production under the context of circular economy.