Critical Properties of Dilute Carbon Dioxide + Entrainer and Ethane + Entrainer Mixtures

Abstract

Critical temperatures and pressures for dilute supercritical fluid−entrainer systems are imperative for the design of efficient and environmentally conscious separation processes. In this study, the constant volume, visual method is used to measure the critical point of CO2 + acetone, CO2 + toluene, CO2 + propan-2-ol, CO2 + methylene chloride, CO2 + benzene, and ethane + benzene mixtures. The dilute entrainer concentration region is emphasized. The estimated experimental error for the critical temperature and pressure measurements is ±0.5 K and ±0.7 bar, respectively. Molar volumes are presented for all systems studied.

Preparation of budesonide and budesonide-PLA microparticles using supercritical fluid precipitation technology

“…However, in general, methylene chloride is miscible in supercritical CO 2 [26]. The average CO 2 density (33-43°C) at the methylene chloride/CO 2 critical points reported by Reaves et al [27] is also shown in Figure 3. Thus, as long as one operates sufficiently above this density, the methylene chloride is not likely to condense out in the precipitation chamber.…”

“…The curves represent pure CO 2 densities calculated using the equation of state given by Angus et al [28]. The dashed line represents the average CO 2 density (between 33 and 43°C) at the methylene chloride/CO 2 critical points reported by Reaves et al [27]. The closed circles represent the operating points that were investigated (same for the run at 40°C and 139 bar).…”

“…The density of pure CO 2 is plotted in Figure 3 as a function of temperature and pressure. In the literature there are limited data on the solubility of methylene chloride in CO 2 [26,27]. However, in general, methylene chloride is miscible in supercritical CO 2 [26].…”

Numerical modeling of jet hydrodynamics, mass transfer, and crystallization kinetics in the supercritical antisolvent (SAS) process

“…1 presents the measured solubilities at 313 K. Solubilities calculated with the PRSV EOS are also presented in this figure. Reaves et al [43] measured the critical points of CO 2 -dichloromethane mixtures, and Jay and Steytler [44] reported that the solubility of ␤-carotene in dichloromethane at 20 • C and 1 bar is 0.667% (w/w). With these data, it is possible to obtain the binary interaction parameters of all pairs in the system CO 2 -dichloromethane-␤-carotene.…”

Co-precipitation of a herbicide and biodegradable materials by the supercritical anti-solvent technique

“…The variation of pressure will also change the solubility of methylene chloride in CO 2 , but it seems that those effects are negligible [16]. microspheres together with some needles of pure diuron.…”