NAMS 2002 Workshop - ICOM 2008

Gas Separation I – 5
Monday July 14, 11:45 AM-12:15 PM, Kaua’i
Development of High Temperature CO2-Selective Porous Ceramic
Membranes
A. Ku (Speaker), GE Global Research, Niskayuna, NY, USA, kua@research.ge.com
V. Ramaswamy, GE Global Research, Niskayuna, NY, USA
J. Ruud, GE Global Research, Niskayuna, NY, USA
P. Willson, GE Global Research, Niskayuna, NY, USA
K. Narang, GE Global Research, Niskayuna, NY, USA
Because of their mechanical durability and thermal and chemical stability,
inorganic membranes have the potential to increase the efficiency of industrial
processes by enabling efficient separation of process gas streams into their
constituents. Numerous industrial processes, including hydrocarbon processing,
steam methane reforming, water gas shift, and CO2 capture from power
generation systems, would benefit from gas separation membranes that operate
at elevated temperatures. Selectivity is a key requirement for membranes. In
general, porous membranes are more selective for the smaller or lighter
molecules in a gas mixture. However, the mechanism of selective surface
transport, due to gas adsorption on the pore walls, can increase the flux of the
heavier molecule resulting in a reverse selective membrane.
Surface transport of adsorbed CO2 can lead to CO2-selectivity in porous
membranes, but is believed to be a low temperature effect because of desorption
of the gas upon heating. We will describe efforts to develop porous ceramic
membranes with enhanced surface transport of CO2 at elevated temperatures.
Based on a conceptual framework that allows screening for promising materials
through chemisorption properties, we identified several promising candidate
oxides and fabricated supported microporous membranes. We will report the gas
permeation and separation properties of our oxide membranes against a
microporous silica benchmark with substantial room temperature CO2/H2
selectivity.
Acknowledgement: This material is based partly upon work that was supported
by the U.S. Department of Energy under award number DE-FC26-05NT42451.