H -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 H -free polyethylene terephthalate (PET) conversion to BTX (benzene, toluene and xylene) was achieved by unlocking hidden hydrogen in the ethylene glycol part over Ru/Nb O catalyst. Among the whole process (hydrolysis, reforming and hydrogenolysis/decarboxylation), the parallel hydrogenolysis and decarboxylation were competing and the rate-determining step. Ru/Nb O exhibited superior hydrogenolysis and poorer decarboxylation performance in direct comparison with Ru/NiAl O , accordingly contributing to the distinct selectivity to alkyl aromatics among BTX. Ru species on Nb O , unlike those on NiAl O , showed more Ru species owing to the strong interaction between Ru and Nb O , restricting the undesired decarboxylation. Along with NbO species for C-O bond activation, excellent reactivity towards the H -free conversion of PET back to BTX with alkyl aromatics as dominant species was achieved. This H -free system was also capable of converting common real PET plastics back to BTX, adding new options in the circular economy of PET.