High-Pressure Phase Equilibrium for Carbon Dioxide－Isomeric Butanol Systems

• Main Authors: Po-Hung Chen, 陳柏宏
• Other Authors: Huey-Ing Chen
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/gg377z

碩士 === 國立成功大學 === 化學工程學系碩博士班 === 90 === In this study, the improved-static type phase equilibrium apparatus was fixed to measure the phase equilibrium data of CO2+n-butanol, CO2+iso-butanol, CO2+2-butanol, and CO2+tert-butanol binary system at temperature 331.93, 341.59, and 351.27 K, and pressure from 50 to 120 bar. The phase equilibrium for CO2+H2O+n-butanol ternary system was also measured at temperature 331.93, 341.59, and 351.27 K, and pressure 60 and 80 bar. In order to ensure the accuracy and reliability of these measurements, the experimental data were compared with literatures and found these were in quite good agreement. In addition, the Soave-Redlich-Kwong equation of state and Peng-Robinson equation of state with conventional two-parameter mixing rule were used to regress the experimental data for the four CO2+isomeric butanol systems. The thermodynamic properties including the binary interaction parameters, critical conditions, Henry’s constants, infinite dilute partial molar volumes, and Margules constants for these binary systems were also estimated. It showed that Soave-Redlich-Kwong equation of state obtained the better fitting results with average deviations less than 1.1 %. Comparing the mutual solubilities of CO2+isomeric butanol systems, it indicated that they were decreased in the order of CO2+tert-butanol, CO2+2-butanol, CO2+iso-butanol, and CO2+n-butanol. And the mutual solubilities increase with the increasing pressure and decrease with the increasing temperature. Furthermore, the phase behaviors of CO2+isomeric butanol systems can be well correlated by the structural properties of the corresponding butanols.