High-Pressure Vapor-Liquid Equilibria for CO₂ + 2-Butanol, CO₂ + Isobutanol, and CO₂ + tert-Butanol Systems

In this study, the vapor-liquid equilibrium data of CO₂ + isobutanol, CO₂ + 2-butanol, and CO₂ + tert-butanol systems were measured with an improved static-type phase equilibrium apparatus at temperatures of (331.9, 341.6, and 351.3) K and pressures from (50 to 120) bar. To ensure the accuracy and reliability of these measurements, the experimental data were compared with literature values, and these were found to be in quite good agreement. The mutual solubilities of CO₂ + isomeric butanol systems decreased in the following order: CO₂ + tert-butanol, CO₂ + 2-butanol, and CO₂ + isobutanol. The temperature and pressure effects on mutual solubilities between CO₂ and isomeric butanols were also demonstrated and discussed.