(505b) Ionic Liquid Containing Mixed Matrix Membranes for O2 Separation

Polymeric mixed matrix membranes containing ionic liquid were fabricated.  Matrimid^® and 1-hexyl-3-methylimidalzolium bis(trifluoromethyl sulfonyl) imide ([hmim][Tf₂N]) were selected as the polymeric and ionic liquid materials respectively. Inorganic zeolite sieves were selected as the sieving material. Membranes with four different morphologies, named a, b, c and d were prepared via a dry-wet nonsolvent-induced phase separation procedure.  All membranes except type a membranes contain zeolite sieves, and the porosity of the membranes was tuned using additives. The membrane type a had a low separation performance for O₂/N₂; however, upon adding zeolite sieves and changing the fiber morphology, better permeance and selectivity were achieved. The morphology of the membranes was characterized by measuring the volume fraction of the polymer, macro-voids, and micro-voids for each type of membrane.  The calculated porosities of both the bulk and the micro-porous region of the membrane were then related to the transport properties of membranes. Permeance and selectivity for O_2/N₂ separation are reported for ionic liquid containing mixed matrix membranes from 22 to 75^o C.