An Advanced Facilitated Transport Membrane for CO2 Capture from Dilute Streams

Coal-fired power plants generate 45% of the electricity in the United States and they are also a major source of CO2 emissions. Low- cost processes for CO2 capture are being developed but these leave about 1% CO2 in the effluent. Unfortunately, it is difficult to remove CO2 from these low concentration streams. Chemical absorption is the option of choice at low CO2 concentrations but these compounds tend to bind CO2 strongly, resulting in high regeneration costs. Membranes offer promise because of their relative simplicity. Unfortunately, they have low selectivity for CO2 over air and generally require higher pressures for optimum performance. In this SBIR Phase I project, Reaction Systems, Inc. will develop and test an advanced facilitated transport membrane for CO2 capture from dilute coal-relevant process streams. This membrane combines the high CO2 selectivity of chemical absorption with the simplicity of a modular membrane without the need for high feed pressures. It will have lower energy costs because it avoids the higher feed pressures needed for polymeric membrane separation and the temperature cycling necessary for absorption and regeneration. Because of the high selectivity, it is possible to generate very high CO2 concentration permeate streams from the feed stream. The technology being developed will reduce the amount of CO2 emitted into the atmosphere by power plants.

Commercial Applications and Other Benefits: The development of a membrane that effectively removed CO2 down to ppm levels would be a substantial benefit to the severe climate change problem developing in Earth. It would significantly reduce CO2 contributions from coal fired power plants to the point that these sources, once considered among the worst polluters, could be used as examples of how to apply advanced technologies to solve pressing problems of the time.