Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Depolymerization of Polycarbonate Waste by Ethylene Glycol

에틸렌글리콜을 이용한 폐폴리카보네이트 해중합 특성

  • Kim, Dongpil (Department of Chemical Engineering, Chungnam National University) ;
  • Kim, Bo-kyung (Department of Chemical Engineering, Chungnam National University) ;
  • Cho, Youngmin (Department of Chemical Engineering, Chungnam National University) ;
  • Han, Myungwan (Department of Chemical Engineering, Chungnam National University) ;
  • Kim, Beom-Sik (New Chemical Research Division, Korea Research Institute of Chemical Technology)
  • 김동필 (충남대학교 공과대학 화학공학과) ;
  • 김보경 (충남대학교 공과대학 화학공학과) ;
  • 조영민 (충남대학교 공과대학 화학공학과) ;
  • 한명완 (충남대학교 공과대학 화학공학과) ;
  • 김범식 (한국화학연구원)
  • Received : 2008.06.15
  • Accepted : 2008.07.05
  • Published : 2008.10.31
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Abstract

A method for the depolymerization of polycarbonate waste by glycolysis using ethylene glycol without catalyst was explored in order to get the monomer bisphenol A (BPA). The effect of operation variables such as reaction time, reaction temperature, EG/PC weight ratio and the kinetic of glycolysis were studied. It was found that the polymerization reaction has two different activation energies depending on the reaction temperature. A drop in activation energy with temperature indicates that the reaction mechanism has shifted from one of a succession of elementary steps to another in the series. The maximum yield of BPA of 95.6% was achieved at reaction temperature $220^{\circ}C$ for 85min with EG/PC weight ratio 4.

본 연구에서는 촉매를 사용하지 않고 에틸렌글리콜(EG)을 이용하여 비스페놀 A(BPA)를 얻기 위한 폴리카보네이트(PC) 해중합 방법에 대하여 연구하였다. 반응시간, 반응온도, 에틸렌글리콜 양에 따른 비스페놀 A의 수율에 대하여 알아 보았으며, 반응속도식을 구하였다. 에틸렌글리콜에 의한 해중합 반응은 반응 온도에 따라 활성화 에너지가 높은 쪽에서 낮은 쪽으로 변하였고, 이는 이 반응이 여러 단계의 직렬반응으로 이루어진 것을 나타낸다. 비스페놀 A의 최대수율은 EG/PC 무게비 4, 반응온도 $220^{\circ}C$, 반응시간 85분에서 95.6%였다.

Keywords

References

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