부산대학교 도서관

The solubility of carbon dioxidein nine ionic liquids (ILs), at298 K, 313 K, and 333 K and pressures up to 9 MPa, is presented. Thesolubility of CO2in the selected ILs increases with increasingpressure and decreases with increasing temperature, as expected. Theeffect of several different anions on the solubility of CO2with a common 1-ethyl-3-methylimidazolium cation is studiedin this work. The anions compared were hydrogen sulfate ([emim][HSO4]), methylsulfate ([emim][MeSO4]), methane sulfonate([emim][MeSO3]), thiocyanate ([emim][SCN]), and diethylphosphate([emim][DEP]). The results for 1-ethyl-3-methylimidazolium hydrogensulfate are particularly interesting and can be explained based onthe stronger attractive interactions between the IL and CO2, which is supported by quantum calculations. Other ILs investigatedwere ethyl(tributyl)phosphonium diethylphosphate ([P2444][DEP]), 1-hexyl-3-methylimidazolium trifluoromethane sulfonate([hmim][OTf]), 1-(2-hydroxyethyl)-3-methylimidazolium trifluoroacetate([OHemim][TFA]), and trihexyl tetradecylphosphonium bis(trifluoromethylsulfonyl)imide([P66614][Tf2N]). Using the new data for the[emim]+ILs, in concert with data from the literature,these ILs were selected primarily to study the effect on the solubilityof changing the cation. Of particular note is the high solubilityof CO2in the trihexyltetradecylphosphoniumbased IL compared with its imidazolium equivalent. A brief discussionis presented to explain the observed solubility results. [ABSTRACT FROM AUTHOR]