H2‐free Plastic Conversion: Converting PET back to BTX by Unlocking Hidden Hydrogen.

The strong desire for a circular economy makes obtaining fuels and chemicals via plastic degradation an important research topic in the 21st century. Here, the first example of the H2‐free polyethylene terephthalate (PET) conversion to BTX (benzene, toluene and xylene) was achieved by unlocking hidden hydrogen in the ethylene glycol part over Ru/Nb2O5 catalyst. Among the whole process (hydrolysis, reforming and hydrogenolysis/decarboxylation), the parallel hydrogenolysis and decarboxylation were competing and the rate‐determining step. Ru/Nb2O5 exhibited superior hydrogenolysis and poorer decarboxylation performance in direct comparison with Ru/NiAl2O4, accordingly contributing to the distinct selectivity to alkyl aromatics among BTX. Ru species on Nb2O5, unlike those on NiAl2O4, showed more Ruδ+ species owing to the strong interaction between Ru and Nb2O5, restricting the undesired decarboxylation. Along with NbOx species for C−O bond activation, excellent reactivity towards the H2‐free conversion of PET back to BTX with alkyl aromatics as dominant species was achieved. This H2‐free system was also capable of converting common real PET plastics back to BTX, adding new options in the circular economy of PET. [ABSTRACT FROM AUTHOR]