THIN LAYER IMMOBILIZED LIQUID MEMBRANES FOR GAS SEPARATIONS

THE NEED FOR ENERGY CONSERVATION TO REDUCE US DEPENDENCE ON POTENTIALLY UNSTABLE FOREIGN ENERGY SUPPLIES IS WELL DOCUMENTED. ONE MAJOR POTENTIAL ENERGY CONSERVATION MEASURE IS COMBUSTION WITH OXYGEN ENRICHED AIR. CONVENTIONAL METHODS FOR PRODUCING OXYGEN ENRICHED AIR ARE UNECONOMICAL AND HENCE ARE NOT PRACTICED. MEMBRANE PROCESSES, ESPECIALLY THOSE BASED ON IMMOBILIZED LIQUID MEMBRANES ARE CHARATERISICALLY SIMPLE AND POTENTIALLY HIGHLY ECONOMICAL TO OPERATE. LIQUID MEMBRANE CONCEPTS PROPOSED TO DATE EMPLOY PRINCIPALLY SYMMETRIC MICROPOROUS POLYMERIC STRUCTURES TO HOST THE IMMOBILIZED LIQUID BARRIER. CONSEQUENTLY, THE THICKNESS OF THE LIQUID MEMBRANE IS THE SAME AS THE SUPPORT STRUCTURE'S THICKNESS -- TYPICALLY 100 TO 200 MICRONS. SINCE IN MANY GAS TRANSPORT THROUGH LIQUID MEMBRANES IS DIFFUSION-LIMITED, REDUCED LIQUID LAYER THICKNESSES ARE HIGHLY DESIREABLE. THE PROPOSED PROGRAM IS CONCERNED WITH THE DEVELOPMENT OF THIN IMMOBILIZED LIQUID MEMBRANES THROUGH THE USE OF ASYMMETRIC POLYMERIC MICROPOROUS STRUCTURES WHEREBY THE LIQUID LAYER IS FORMED WITHIN THE SMALLER PORE REGION WHICH IS TYPICALLY IN THE ORDER OF A FEW MICRONS THICK. HOLLOW FIBER MEMBRANE SUPPORTS WILL BE USED DUE TO BOTH THEIR COMPACT NATURE AND PREFERENCE OVER OTHER GEOMETRIES FOR GAS SEPARATIONS. OXYGEN ENRICHMENT EVALUATION WILL, IN PHASE I, CENTER ON MEMBRANE FORMATION WITH PASSIVE LIQUIDS. REACTIVE LIQUIDS (FACILITATED TRANSPORT) WILL BE EXPLORED IN PHASE II.