Study on immobilized liquid membrane using ionic liquid and PVDF hollow fiber as a support for CO2/N2 separation

This study focuses on improving the CO2 permeability and stability of the liquid membrane. To improve permeability, polymeric hollow fiber support with a high effective area per unit volume were prepared with various dope composition as a support; to improve stability, the effects of varying the structure of the support and immobilization conditions were observed and analyzed. For the experiment, 1-ethyl-3-methylimidazolium-bis(trifluoromethylsulfonyl) imide ([emim][Tf2N]) and polyvinylidene fluoride (PVDF) were used. For immobilization of the [emim][Tf2N], the liquid was diluted to 40 vol.% in methanol and immobilized liquid membranes (ILMs) were prepared as gas permeation modules. The prepared ILM module was characterized by single gas permeation of CO2 and N2 according to feed pressure at atmosphere temperature. All of prepared modules were observed with high CO2 permeability of over 2600 barrer, respectively. However, stability on pressure was affected by support structure.