High presure phase behavior and thermodynamic modelling of the carbon dioxide + chloroform + globalide system

20/05/2023 20:08

Davi Gustavo Lisboa Girardi, Aurora Lorini Letsch, Evertan Antonio Rebelatto, Diego Alex Mayer, José Vladimir de Oliveira

April 2023


The high-pressure phase behavior of the ternary system constituted by carbon dioxide + globalide + chloroform was studied. Experiments were conducted applying the synthetic-visual method in a variable-volume view cell at a mass ratios of globalide to chloroform of 0.5:1, 1:1, and 2:1, over a temperature range from 313.15 to 343.15 K, and pressures from 5.17 to 20.25 MPa. Phase transitions of vapor–liquid bubble point (VLE-BP), vapor–liquid dew point (VLE-DP), liquid-liquid (LLE), and vapor–liquid-liquid (VLLE) type were observed. Furthermore, through the P-w diagram, the phase behavior of the ternary system in chloroform free-basis was analyzed between 0.4250 to 0.9735 of carbon dioxide mass composition. It has been observed that high quantities of chloroform lead to lower transition pressures. Moreover, PT-diagrams efficiently displayed that higher pressures are necessary to achieve a single phase medium as temperature rises, which characterize LCST behavior. PR-vdW2 model was used to estimate binary interaction parameters. Additionaly, the ternary system was compared with binary systems avaiable in the literature. The data presented in this work provides necessary information for the optimization and improvement of poly(globalide) synthesis in supercritical media.