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Neutral Hydrolysis of Post-Consumer Polyethylene Terephthalate Waste in Different Phases
Post-consumer polyethylene terephthalate (PET) was hydrolyzed in pure water over a wide range of temperatures (190−400 °C) and pressures (1−35 MPa) to produce terephthalic acid (TPA). Solid or molten PET was subjected to water as a saturated vapor, superheated vapor, saturated liquid, compressed liquid, and supercritical fluid. The highest TPA yields were observed for the hydrolysis of molten PET in saturated liquid water. Isothermal and non-isothermal hydrolysis of PET was also explored. Rapidly heating the reactor contents at about 5−10 °C/s (“fast” hydrolysis) led to high TPA yields, as did isothermal PET hydrolysis, but within 1 min instead of 30 min. Notably, these conditions resulted in the lowest environmental energy impact metric observed to date for uncatalyzed hydrolysis.
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- Award ID(s):
- 2029397
- PAR ID:
- 10466765
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Sustainable Chemistry & Engineering
- Volume:
- 11
- Issue:
- 18
- ISSN:
- 2168-0485
- Page Range / eLocation ID:
- 7203 to 7209
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acssuschemeng.3c00946
