paraffin mixtures

The ideal separation factor for propylene over propane approached 3.2 through the use of room temperature ionic liquids (ILs) such as 1-methyl-3-octyl imidazolium nitrate (MOIM+NO3-, 98%) and 1-butyl-3-methyl imidazolium tetrafluoroborate (BMIM+BF4-, 98%), which may be attributable to facilitated olefin transport via specific and reversible interactions between ILs and propylene, but not propane. Specific and reversible interactions were verified experimentally from transient sorption/desorption data and FT-IR spectroscopy and theoretically by quantum mechanical calculations. The mixed gas selectivity for propylene/propane mixtures (50/50 vol%) was 2.8 through ILs whereas with PEG 400 (Mw=400), which has nearly the same viscosity, the selectivity was only 1.2. This study demonstrated for the first time facilitated olefin transport through ILs. (C) 2012 Elsevier B.V. All rights reserved.This work was supported by the National Research Foundation of Korea (NRF) for the WCU (World Class University) program (R31-2008-000-10092), the Korea Center for Artificial Photosynthesis (KCAP) located in Sogang University (NRF-2009-C1AAA001-2009-0093879), and the Center for Next Generation Dye-Sensitized Solar Cells (No. 2011-0001055), through the National Research Foundation of Korea funded by the Ministry of Education, Science, and Technology