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A new type of CO2-capture media based on permeable polymer microcapsules has been developed by teams of scientists at Lawrence Livermore National Laboratory (Livermore, Calif.; www.llnl.gov), Harvard University (Cambridge, Mass.; www.harvard.edu) and the University of Illinois-Urbana-Champaign (www.illinois.edu). The materials have several advantages over amine-based approaches to absorbing CO2 from power-plant fluegas. Using microfluidics techniques, the scientists produced microcapsules (photo) that contain a liquid sorbent — sodium carbonate solution combined with a catalyst — that can absorb CO2 quickly. The microcapsules are made from a highly permeable silicone polymer material that allows CO2 molecules to pass through, but prevents the sorbent material from escaping. By forcing the sorbent to remain in small droplets, the microcapsules can maximize the surface area that contacts CO2. The permeable microbeads are inexpensive to make, easy to handle and produce minimal waste, the researchers say, and with encapsulated fluids inside, they allow users to combine the advantages of solid and liquid CO2-capture media in the same system, while avoiding many of the environmental and corrosion issues posed by amine-based CO2 capture. Microcapsules…