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Ahn, Jae-Myoung;Ihm, Bang-Hyun;Kim, Sun-Wook;Shim, Jae-Jin
- Clean Technology
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- v.13 no.1 s.36
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- pp.46-53
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- 2007
We depolymerized PET in supercritical methanol and observed the yield of DMT at various reaction conditions. At subcritical state below $240^{\circ}C$, the yield of DMT was very low, about only 50%. It increased dramatically to 80% at supercritical state above $260^{\circ}C$, thereafter the increasing rate was reduced significantly. Similarly, at subcritical state of 6.89 MPa, the DMT yield was only 50%, but it increased abruptly to 85% at supercritical state of 10.34 MPa, yielding no further increase above the pressure. Within 10 minutes after the beginning of the reaction, the DMT yield reached 80%, indicating that the significant portion of the reaction has proceeded, and then, the yield increased slowly. The methanol/PET ratio of 8 showed the maximum DMT yield. We found the optimum depolymerization condition fur PET methanolysis is temperature $300^{\circ}C$, pressure 10.34 MPa, reaction time 40 minutes, and methanol/PET ratio of 8.
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Kwak, Cheol Hwan;Seo, Sang Wan;Kim, Min Il;Im, Ji Sun;Kang, Seok Chang
- Applied Chemistry for Engineering
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- v.32 no.1
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- pp.42-48
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- 2021
In this study, a sensor for detection of nitric oxide (NO) gas was developed using petroleum pitch-based activated carbon which was synthesized from pyrolysis fuel oil (PFO). Polyethylene terephthalate (PET) was added to increase molecular weight by stimulating a polymerization of components in PFO during the pitch synthesis process. The increase in the molecular weight of pitch contributed to the improvement of textural properties of activated carbon, such as the specific surface area and micropore volume. It also enhanced the sensitivity of NO gas sensor based on the activated carbon. In addition, the effect of PET addition during the pitch synthesis on the surface oxygen content and conductivity of activated carbon was investigated. Finally, the correlation of the sensitivity with physical properties of activated carbon was analyzed.
https://doi.org/10.14478/ace.2020.1108 인용 PDF KSCI

Yoo, Dong-Il;Lee, Eung-Eui;Shin, Youn-Sook
- Textile Coloration and Finishing
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- v.10 no.1
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- pp.20-24
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- 1998
Oligomeric extracts of poly(ethylene terephthalate-co-ethylene isophthalate)s [(PET/EI] are analyzed by high performance liquid chromatography(HPLC) and nuclear magnetic resonance spectroscopy (NMR). Existence of separated peaks for small cyclics of trimer and tetramer gives the existence of structural isomeric forms. NMR confirms that cyclization of PET/EI occurs more easily at the site of isophthaloyl unit.
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