Group contribution lattice fluid equation of state for CO₂–ionic liquid systems: An experimental and modeling study

Abstract

The group contribution lattice fluid equation of state (GCLF EOS) was first extended to predict the thermodynamic properties for carbon dioxide (CO 2 )-ionic liquid (IL) systems. The group interaction parameters of CO 2 with IL groups were obtained by means of correlating the exhaustively collected experimental solubility data at high temperatures (above 278.15 K). New group parameters between CO 2 and IL groups were added into the current parameter matrix. It was verified that GCLF EOS with two kinds of mixing rules could be used for predicting the CO 2 solubility in ILs, and volume expansivity of ILs upon the addition of CO 2 , as well as identifying the new structure-property relation. Moreover, it is the first work on the measurement of the solubility of CO 2 in ILs at low temperatures (below 278.15 K), manifesting the applicability of predictive GCLF EOS over a wider temperature range.

UNIFAC model for ionic liquid‐CO (H2) systems: An experimental and modeling study on gas solubility

“…When Eq. is used, the Henry's constants of CO 2 in ILs are derived from the literature, whereas some data related to CO and H 2 in ILs were extracted from the literature and the others originate from this work. The detailed values and the corresponding literature are listed in Supporting Information Table S8.…”

“…The solubility of CO in ILs at temperatures below 293.2 K was measured using a low‐temperature equilibrium apparatus, the details of which have been described in our previous publication . In this apparatus, the temperature was controlled with cooling ethanol with a fluctuation of ±0.1 K, and the system pressure was measured by a pressure gauge with a range of 0–9.999 MPa and a fluctuation of ±0.001 MPa.…”

“…These values were subsequently used to obtain the parameters between the IL and CO (H 2 ) groups. In this work, the IL molecule was decomposed into several functional groups in a manner similar to that adopted by Lei and coworkers, Kim et al, Breure et al, and others . The fitting procedure using the SOLVER function in Microsoft Excel 2007 to obtain the group binary interaction parameters is similar to that used in our previous publications, where the optimization algorithm of Newton's central difference was chosen.…”

Adsorptive absorption: A preliminary experimental and modeling study on CO2 solubility

“…Recent progress in this field includes the development of regular ILs, task-specific ILs, polymerized ILs, and mixtures of ILs that possess desirable solubility and selectivity for capturing CO 2 . To meet the high CO 2 separation requirement (limited to ppm level) in the syngas purification of the Fischer-Tropsch (FT) synthesis and NH 3 (ammonia) production, we measured the solubility of CO 2 in pure ILs and in a binary mixture of ILs at low temperatures (down to 228 K) (Dai et al, 2013;Lei et al, 2014). However, all studies were limited to absorption by liquid solvents.…”

CO2 capture by methanol, ionic liquid, and their binary mixtures: Experiments, modeling, and process simulation

“…A number of predictive thermodynamic models are available for modeling the solubility of CO 2 in ILs . Among others, the universal quasichemical (UNIQUAC) functional‐group activity coefficients (UNIFAC) model for ILs constantly developed by our group (UNIFAC‐Lei model) has attracted wide attention, and it produces solid outcomes in various‐specific applications due to the unique advantages: (1) it provides quantitative accurate predictions; (2) its formulation is simple, and thus the calculation speed is rapid; (3) its parameters can be readily utilized in the modern simulation packages (e.g., Aspen Plus, PROII, and ChemCAD) for simulation and optimization of the desired industrial processes; and (4) in terms of the UNIFAC‐Lei preferable decomposition approach, the introduced main groups and subgroups together with their derived parameters are appropriate for the ILs‐based designing methodologies for specific applications .…”