Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Isobaric Vapor-Liquid Equilibrium of Toluene and Cresol Systems

톨루엔-크레졸의 정압 기-액 평형

  • Kang, Dong-Yuk (Department of Advanced Chemicals and Engineering, Chonnam National University) ;
  • Jang, Hoi-Gu (Department of Applied Chemical Engineering, Chonnam National University) ;
  • Han, Chang-Nam (Department of Advanced Chemicals and Engineering, Chonnam National University) ;
  • Rho, Seon-Gyun (Department of Applied Chemical Engineering, Chonnam National University) ;
  • Cho, Dong Lyun (Department of Advanced Chemicals and Engineering, Chonnam National University) ;
  • Kang, Choon-Hyoung (Department of Applied Chemical Engineering, Chonnam National University)
  • 강동육 (전남대학교 신화학소재공학과) ;
  • 장회구 (전남대학교 응용화학공학부) ;
  • 한창남 (전남대학교 신화학소재공학과) ;
  • 노선균 (전남대학교 응용화학공학부) ;
  • 조동련 (전남대학교 신화학소재공학과) ;
  • 강춘형 (전남대학교 응용화학공학부)
  • Received : 2009.10.09
  • Accepted : 2009.10.29
  • Published : 2009.12.31
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Abstract

To a first approximation, phase behavior of a system becomes increasingly skew in proportion to the boiling point difference of system-forming constituents. Therefore, phase behavior data of a system of a large boiling point difference are to be experimentally measured for thorough understanding of the thermodynamic characteristics of such system. In this work, isobaric vapor-liquid equilibrium of a mixture consisting of toluene and cresol, which shows a large boiling point difference of nearly $100^{\circ}C$ and is consequently expected to be considerably nonideal, was measured by using a recirculating equilibrium cell at various subatmospheric pressures ranging from 10 kPa to 60 kPa. The measured VLE data were correlated with NRTL and UNIQUAC models in a satisfactory manner and the accompanying thermodynamic consistency test represented soundness of the measurements. In addition, the excess molar volume of the mixture was also measured with a vibrating densitometer and correlated with a Redlich-Kister polynomial. A negative excess volume prevailed over the whole concentration range, which indicates a favorable attraction between toluene and cresol isomers and results in an extensive miscibility.

일반적으로 비등점의 차이가 큰 물질들은 그 물리적 성질의 차이로 인해 혼합물에서 비이상적인 상거동을 보이며, 이러한 혼합물의 상거동 특성을 이해하기 위해서는 정확한 실험적 데이터가 필요하다. 본 연구에서는 재순환 평형조가 포함된 기-액 상평형 장치를 사용하여 10, 30, 60 kPa에서 톨루엔과 크레졸 혼합물에 대한 정압 기-액 평형 실험을 행하였다. 측정한 기-액 평형 데이터는 NRTL과 UNIQUAC 모델식을 이용하여 잘 적합할 수 있었으며 Gibbs/Duhem 식에 근거한 열역학적 건전성 테스트를 수행하여 실험결과의 건전성을 확인하였다. 한편, 혼합물의 과잉몰부피를 측정하여 Redlich-Kister 다항식으로 나타내었다.

Keywords

References

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