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Language: korean

Conflict of Interest: In relation to this article, we declare that there is no conflict of interest.

Publication history: Received September 12, 2009
Accepted September 28, 2009

This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/bync/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

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에틸렌글리콜을 이용한 PET 해중합 특성

Depolymerization of PET by Ethylene Glycol

황휘동 김보경 우대식 한명완^†

Hwidong Hwang Bokyung Kim Daesik Woo Myungwan Han^†

충남대학교 화학공학과, 305-764 대전광역시 유성구 궁동 220번지

Dept. of Chemical Engineering, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejeon 305-764, Korea

mwhan@cnu.ac.kr

Korean Chemical Engineering Research, December 2009, 47(6), 683-687(5), NONE Epub 6 January 2010

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Abstract

본 연구에서는 촉매 존재 하에서 에틸렌글리콜(EG)를 이용하여 글리콜리시스를 통해 PET(Poly ethylene terephthalate)을 해중합하여 BHET(bis-hydroxyethyl terephthalate)를 얻기 위한 방법에 대하여 연구하였다. 촉매는 zinc acetate가 사용되었고, 생성물은 high performance liquid chromatography(HPLC)으로 분석하였다. 반응 시간, 반응 온도, EG양과 같은 조건들의 영향을 알아보았으며, 반응 속도식을 구하였다. 그 결과 반응 온도와 반응 시간이 증가함에 따라 BHET의 수율과 해중합 속도는 증가하였지만, 너무 높은 반응 온도 250 ℃에서는 BHET가 중합반응을 일으켜 230 ℃ 보다 수율이 낮게 나타났다. 1차 반응속도 모델을 가정하여 반응 활성화에너지를 구하였다. 얻어진 활성화 에너지는 210 ℃ 이상과 210 ℃ 이하에서 각각 37.8, 149.6 kJ/mol이었다. 이는 이 반응이 다단 연속 반응임을 보여준다. BHET의 최대 수율은 반응 온도 230 ℃, 반응 시간 6시간 그리고, EG/PET의 비율이 4일 때 가장 높은 71%의 수율을 나타내었다.

A method for depolymerization of PET by catalyzed glycolysis with an excess ethylene glycol(EG) to recover bis-hydroxyethyl terephthalate(BHET) was investigated. The product was analyzed by high-performance liquid chromatography(HPLC). Effects of operation variables such as reaction temperature, reaction time, EG/PET weight ratio were examined and kinetics of the glycolysis was studied. High temperature increases the rate of depolymerization and the yield of BHET. But, repolymerization rate was also high at too high temperature and the yield at 250 ℃ was shown to be lower than that at 230 ℃. First order reaction model was proposed to describe the glycolysis reaction. Activation energies for the reaction were obtained to be 37.8 kJ/mol above 210 ℃ and 149.6 kJ/mol below 210 ℃, which shows the glycolysis reaction is a multiple reaction. A maximum yield of BHET of 71% was achieved at a reaction temperature of 230 ℃ for 6 hr with an EG/PET weight ratio 4.

Keywords

PET BHET Depolymerization Glycolysis Ethylene Glycol

References

Vaidya UR, Nadkarni VM, J. Appl. Polym. Sci., 34, 235 (1987)
Vaidya UR, Nadkarni VM, J. Appl. Polym. Sci., 35, 775 (1988)
Alvarezcastillo A, Castano VM, Polym. Bull., 32(4), 447 (1994)
Alvarezcastillo A, Castano VM, Polym. Bull., 35(1-2), 187 (1995)
Baligar S, Wong WT, J. Polymer Sci. Part A Polym. Chem., 27, 2071 (1989)
Kao CY, Cheng WH, Wan BZ, Thermochim. Acta, 292(1-2), 95 (1997)
Chen CH, Chen CY, Lo YW, Mao CF, Liao WT, J. Appl. Polym. Sci., 80(7), 943 (2001)
Campanelli JR, Kamal MR, Cooper DG, J. Appl. Polym. Sci., 54(11), 1731 (1994)