Abstract
Alkali-decomposition (depolymerization) of poly(ethylene terephthalate) (PET) was studied in a mixed solvent of an alcohol (ethanol or methanol) and ether (dioxane, tetrahydrofuran, or dimethoxyethane). The time for complete decomposition (>96%) of solid PET with NaOH in methanol at 60°C was 40 min when dioxane (10 vol%) was added as co-solvent in the reaction mixture, whereas 7 h without dioxane. Disodium terephthalate, a product, precipitated quantitatively in the media and was separated easily. From the filtrate, ethylene glycol (EG) was recovered by distillation while, for practical use, the major portion of the filtrate was recycled repeatedly as the reaction medium.
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Hu, LC., Oku, A., Yamada, E. et al. Alkali-Decomposition of Poly(ethylene terephthalate) in Mixed Media of Nonaqueous Alcohol and Ether. Study on Recycling of Poly(ethylene terephthalate). Polym J 29, 708–712 (1997). https://doi.org/10.1295/polymj.29.708
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DOI: https://doi.org/10.1295/polymj.29.708
Keywords
- Poly(ethylene terephthalate) (PET)
- Plastic Recycling
- Alkali Decomposition
- Mixed Solvent System
- Methanol
- Ethanol
- Dioxane
- Terephthalic Acid
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