Solid-state silver polymer electrolyte membranes containing AgNO3 dissolved in poly(2-ethyl-2-oxazoline) (POZ) as an olefin carrier are not efficient for the separation of olefin/paraffin mixtures (selectivity ∼1). The addition of fumed silica nanoparticles into the POZ/AgNO3 complex membranes, however, resulted in a surprisingly significant enhancement of the permeance and selectivity (higher than 80) for propylene/propane mixtures. These enhancements are explained in terms of the silver ion activity in olefin coordination. FT-IR, X-ray photoelectron spectroscopy (XPS) and FT-Raman demonstrate that the silver ion activity continuously increases by Lewis acid-base interactions upon incorporation of the silica nanoparticles up to 0.1 mole ratio of silica, above which it abruptly decreases. Furthermore, the structural change of polymer electrolyte membranes took place by the presence of nanoparticles, supported by the Tg measurement.
Bibliographical noteFunding Information:
We acknowledge the partial financial support from Hanyang University through an internal research fund. KC acknowledges the financial support of the National Research Laboratory Program (Grant M1-0104-00-0191) and the Ministry of Education through the Brain Korea 21 Program at Seoul National University.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Physical and Theoretical Chemistry
- Filtration and Separation