Preparation and Gas Permeability Measurements of PVDF-HFP/Ionic Liquid Gel Membranes

PVDF-HFP/이온성 액체 겔 분리막 제조 및 기체 투과도 측정

  • Ko, Youngdeok (Department of Chemical and Biological Engineering, Hanbat National University) ;
  • Park, Doohwan (Green House Gas Research Center, Korea Institute of Energy Research) ;
  • Baek, Ilhyun (Green House Gas Research Center, Korea Institute of Energy Research) ;
  • Hong, Seong Uk (Department of Chemical and Biological Engineering, Hanbat National University)
  • 고영덕 (한밭대학교 화학생명공학과) ;
  • 박두환 (한국에너지기술연구원 온실가스연구실) ;
  • 백일현 (한국에너지기술연구원 온실가스연구실) ;
  • 홍성욱 (한밭대학교 화학생명공학과)
  • Received : 2014.05.12
  • Accepted : 2014.09.15
  • Published : 2014.12.10


It is well known that $CO_2$ can be dissolved easily in imidazolium-based room temperature ionic liquids (RTILs). Because of the high $CO_2$ solubility in RTILs, membranes containing RTILs can separate easily gas mixtures such as $CO_2/N_2$ and $CO_2/CH_4$. In this study, we prepared poly(vinylidene fluoride)-hexafluoropropyl copolymer (PVDF-HFP) gel membranes with several RTILs and measured permeabilities of several gases. When the anion of ionic liquids was tetrafluoroborate($BF{_4}^-$), both $CO_2$ permeability and selectivities decreased as the carbon number of the cation increased. When the cation of ionic liquids was 1-ethyl-3-methylimidazolium[emim], $CO_2$ permeability of gel membranes containing bis(trifluoromethane) sulfoneimide($Tf_2N^-$) anion was double compared to those containing tetrafluoroborate($BF{_4}^-$) anion. However, $CO_2/N_2$ and $CO_2/CH_4$ selectivities of the $Tf_2N^-$ case were decreased, whereas the $H_2$ selectivity was almost the same for two cases.


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