A Comparative Study on the Prediction of Vapor-Liquid Equilibria for the Ethanol-Benzene Mixture between Equation of State Model and Liquid Activity Coefficient Model

비이상적 상거동을 보이는 이성분계 혼합물의 기액 상평형 추산을 위한 상태방정식과 액체 활동도계수 모델 사이의 비교연구

  • Cho, Jung-Ho (Department of Chemical Engineering, Kongju National University) ;
  • Lee, Ji-Hwan (Department of Environmental Health, Kyungin Women's College)
  • Received : 2010.04.16
  • Accepted : 2010.05.13
  • Published : 2010.05.31


In this study, a comparative study was performed to predict the vapor-liquid equilibria with maximum azeotropic pressure for ethanol-benzene binary system between an equation of state model and a liquid activity coefficient model. Peng-Robinson equation of state model with a Panatiotopoulos mixing rules (PRP) was used and NRTL liquid activity coefficient model proposed by Renon was selected. The PRP model, even though it has only two binary adjustable parameters, was not inferior to the NRTL model to predict vapor-liquid equilibria for low pressure region of ethanol-benzene system and showed a better prediction capability for high pressure region of ethanol-benzene system than the NRTL model with three binary interaction parameters.


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