APPLICATION OF TECHNOLOGY:
- Post-consumer polyester depolymerization in the presence of diol
- Enables facile recovery of the catalyst from the glycolysis products; as a result, the catalyst can be reused without appreciable loss of activity
- Catalyst shows a broad applicability to various polyester polymer depolymerization
- Easily prepared by the growth of zeolitic imidazolate frameworks (ZIFs) on the surface of Fe3O4 or nano Fe3O4
- Low catalyst level
- Quantitative catalyst separation
- ZIFs are an important subclass of metal-organic frameworks (MOFs) with tunable pores and remarkable thermal and chemical stability, which makes them attractive for numerous catalytic applications.
Researchers at Berkeley Lab have used Fe3O4@ZIF-8 magnetic microspheres as a highly recyclable and efficient catalyst for the depolymerization of various poly(ethylene terephthalate) (PET) polyesters in the presence of ethylene glycol (EG).
The catalyst demonstrates better performance compared to other developed depolymerization processes. For example, at a low catalyst loading (around 1/50, w/w) on the basis of poly(ethylene terephthalate), it achieves around 10 times higher activity than that of the ionic liquid (IL) route. In another case, the catalyst shows 100% of PET conversion with 62% yield of bis(2-hydroxyethyl) terephthalate at 180 °C.
Ultimately, the invention is a novel magnetic catalyst based on MOFs for potential industrial applications.
DEVELOPMENT STAGE: Proven principle
FOR MORE INFORMATION:
STATUS: Patent pending.
OPPORTUNITIES: Available for licensing or collaborative research.