TY - JOUR
T1 - Computing bubble-points of CO2/CH4 gas mixtures in ionic liquids from Monte Carlo simulations
AU - Ramdin, Mahinder
AU - Balaji, Sayee Prasaad
AU - Vicent-Luna, José Manuel
AU - Torres-Knoop, A
AU - Chen, Frank
AU - Dubbeldam, David
AU - Calero, S
AU - de Loos, Theo W.
AU - Vlugt, Thijs J H
N1 - Accepted Author Manuscript
PY - 2016
Y1 - 2016
N2 - Computing bubble-points of multicomponent mixtures using Monte Carlo simulations is a non-trivial task. A new method is used to compute gas compositions from a known temperature, bubble-point pressure, and liquid composition. Monte Carlo simulations are used to calculate the bubble-points of carbon dioxide (CO2) and methane (CH4) mixtures in the ionic liquids (ILs) 1-n-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [bmim][Tf2N] and 1-ethyl-3-methylimidazolium diethylphosphate [emim][dep]. The Continuous Fractional Component Monte Carlo (CFCMC) method in the osmotic ensemble has been used to compute the solubility of CO2/CH4 gas mixtures at different temperatures (T), pressures (P), and gas compositions (yi). The effect of T, P, and yi on the real CO2/CH4 selectivity (i.e., the selectivity of CO2 in the presence of CH4) is investigated. The real selectivity will differ from the ideal selectivity, which is defined as the ratio of the Henry's constants, if the solubility of CO2 is influenced by the presence of CH4. The computed real selectivities are compared with the experimentally obtained real and ideal selectivities. The real CO2/CH4 selectivity decreases with increasing temperature and pressure, while the gas phase composition has a minor effect. The real selectivity is approximately identical to the ideal selectivity for relatively low pressures and low solute concentrations in the liquid phase. The real selectivity deviates from the ideal selectivity as the solute concentration in the liquid phase increases.
AB - Computing bubble-points of multicomponent mixtures using Monte Carlo simulations is a non-trivial task. A new method is used to compute gas compositions from a known temperature, bubble-point pressure, and liquid composition. Monte Carlo simulations are used to calculate the bubble-points of carbon dioxide (CO2) and methane (CH4) mixtures in the ionic liquids (ILs) 1-n-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [bmim][Tf2N] and 1-ethyl-3-methylimidazolium diethylphosphate [emim][dep]. The Continuous Fractional Component Monte Carlo (CFCMC) method in the osmotic ensemble has been used to compute the solubility of CO2/CH4 gas mixtures at different temperatures (T), pressures (P), and gas compositions (yi). The effect of T, P, and yi on the real CO2/CH4 selectivity (i.e., the selectivity of CO2 in the presence of CH4) is investigated. The real selectivity will differ from the ideal selectivity, which is defined as the ratio of the Henry's constants, if the solubility of CO2 is influenced by the presence of CH4. The computed real selectivities are compared with the experimentally obtained real and ideal selectivities. The real CO2/CH4 selectivity decreases with increasing temperature and pressure, while the gas phase composition has a minor effect. The real selectivity is approximately identical to the ideal selectivity for relatively low pressures and low solute concentrations in the liquid phase. The real selectivity deviates from the ideal selectivity as the solute concentration in the liquid phase increases.
KW - Carbon dioxide capture
KW - Gas absorption
KW - Molecular simulation
KW - Natural gas sweetening
KW - Separation selectivity
UR - http://resolver.tudelft.nl/uuid:bed491f0-a8a9-469e-b51c-c3a109b494ae
UR - http://www.scopus.com/inward/record.url?scp=84945550138&partnerID=8YFLogxK
U2 - 10.1016/j.fluid.2015.09.041
DO - 10.1016/j.fluid.2015.09.041
M3 - Article
AN - SCOPUS:84945550138
SN - 0378-3812
VL - 418
SP - 100
EP - 107
JO - Fluid Phase Equilibria
JF - Fluid Phase Equilibria
ER -