Monday, November 9, 2015: 8:32 AM
250B (Salt Palace Convention Center)
CO2 transport membranes have many applications including CO2 capture from industrial combustion processes and membrane reactors. 'Dual phase' membranes are made from a porous, oxygen ion-conducting support that has been infiltrated with molten carbonates. As long as a partial pressure differential exists across the membrane, CO2 will selectively permeate through the membrane as a dissolved CO32- ion, while O- ions are transported in the opposite direction by the support material. Previous research has been done on dual phase membranes in the form of disks, but this project focuses on tubular membranes which are more readily applicable to industrial situations. Using tubular membranes made from Yittria-Stabilized Zirconia and a eutectic mixture of Li, Na, and K carbonates, we were able to fabricate a very thin, dual phase membrane that showed a high flux and permeance of CO2 over a temperature range of 550 to 750°C, comparable to the highest fluxes reported in the literature. The permeability was lower, which may be due to the rate-limiting surface reaction. Current work is being done to improve the membrane performance, including improving the homogeneity of the carbonate coating on the membrane, using a support material with a higher oxygen ion conductivity, and increasing the rate of the surface reaction with a catalyst.