Phase equilibria experiments and calculations for carbon dioxide + methanol binary system

Abstract

Abstract:Vapor-liquid equilibria (VLE) data for the carbon dioxide + methanol system was measured at 293.15, 298.15, 310.15, and 323.15 K. Phase behavior measurements were made in a high-pressure visual cell with variable volume, based on the static-analytic method. The pressure range under investigation was between 4.8 and 95.1 bar. The Soave-Redlich-Kwong (SRK)-EOS coupled with Huron-Vidal (HV) mixing rules and a reduced UNIQUAC model, was used in a semi-predictive approach, in order to represent the phase behavior (critical curve, isothermal VLE) of the system. The topology of the phase behavior of the carbon dioxide + methanol system is satisfactory predicted with the SRK/HV-residual UNIQUAC model. © Versita Warsaw and Springer-Verlag Berlin Heidelberg.

Conductivity Measurements on H2O-Bearing CO2-Rich Fluids

“…The sample was at lower than experimental pressure when opened to the pump (it was compressed 0.84 cm 3 , or about 5.6 % by volume to bring it to experimental pressure) which may have caused exsolution of methanol and some separation by density before flow was started. When the loop was compressed, any methanol that exsolved would have redissolved into the CO 2 , as there is complete miscibility between CO 2 and methanol at the experimental pressure (8 MPa) and at both experimental and room temperature [47]. Note that the conductivity overall was very small (it did not exceed 1.6 nSÁcm -1 ), yet small heterogeneity in the fluid was clearly detected.…”

“…A CO 2 -rich CO 2 -methanol-KCl solution was prepared with a target composition of *90 mol% CO 2 , *10 mol% methanol (neglecting the small concentration of KCl in methanol) using the same procedure as was followed for CO 2 -H 2 O solutions as described above. This composition is in the 1-phase field for the system CO 2 -methanol at both room temperature and the experimental conditions [47]. However, a decrease in pressure during loading (*3 MPa) could place this composition in the 2-phase field until it is returned to experimental pressure [47].…”

“…This composition is in the 1-phase field for the system CO 2 -methanol at both room temperature and the experimental conditions [47]. However, a decrease in pressure during loading (*3 MPa) could place this composition in the 2-phase field until it is returned to experimental pressure [47].…”

High-pressure vapor–liquid and vapor–liquid–liquid equilibria in the carbon dioxide+1-heptanol system

“…The apparatus used in this work is based on the static-analytical method with liquid and vapor phase sampling. The procedure is the same as in our previous papers [4,5,[10][11][12][13][14]. The entire internal loop of the apparatus including the equilibrium cell was rinsed several times with carbon dioxide.…”

“…A detailed description of the experimental apparatus was presented in our previous publications [10,11]. The apparatus used in this work is based on the static-analytical method with liquid and vapor phase sampling.…”