Catalysis

Engineering

Aniline

Dimethyl sulfoxide

Yield (engineering)

Metallurgy

Materials science

Telecommunications

Computer science

Decomposition

Chemical engineering

Polyester

Dissolution

Polymer

Thermodynamics

Laser

Physics

Homogeneous

Organic chemistry

Optics

Degradation (telecommunications)

Composite material

Chemistry

Monomer

Ultrashort pulse

Polyethylene terephthalate

Industrial & Engineering Chemistry Research

Recycling of discarded polyethylene terephthalate (PET) is an important issue for both environmental protection and resource conservation purposes. In this work, a dissolution-degradation strategy has been developed for recycling PET by adding solvents such as aniline, nitrobenzene, 1-methyl-2-pyrrolidinone (NMP), or dimethyl sulfoxide (DMSO) into the traditional PET glycolysis system. The results show that the conversion of PET reaches 100% and the yield of monomer bis(hydroxyalkyl) terephthalate (BHET) reaches 82% during 1 min with zinc acetate as catalyst in DMSO at 463 K. Importantly, this strategy can be applied to a variety of catalysts. The simulation and in situ IR results indicate that the π–π interaction between PET and aromatic solvents plays a key role in PET dissolution, which leads to fast degradation. This promising dissolution-degradation strategy can improve the glycolysis efficiency of PET dramatically and may be applied to the degradation process of other polyesters.

Ultrafast Homogeneous Glycolysis of Waste Polyethylene Terephthalate via a Dissolution-Degradation Strategy