- P-ISSN 1225-0163
- E-ISSN 2288-8985
Solubility data of carbon dioxide (CO_2) in the imidazolium-based ionic liquids with methylsulfate anion are presented at pressures up to about 45 MPa and at temperatures between 303.15 K and 343.15 K. The ionic liquids studied in this work were 1-ethyl-3-methylimidazolium methylsulfate ([emim][mSO_4]), 1-butyl-3-methylimidazolium methylsulfate ([bmim][mSO_4]). The solubilities of CO_2 were determined by measuring the bubble point or cloud point pressures of the binary mixtures using a high-pressure equilibrium apparatus equipped with a variable-volume view cell. The equilibrium pressure increased very steeply at high CO_2compositions. The CO_2 solubility in ionic liquids increased with increase of the total length of alkyl chains attached to the imidazolium cation of the ionic liquids. The phase equilibrium data for the CO_2 + ionic liquid systems have been correlated using the Peng-Robinson equation of state.