PASSIVE CO2 REMOVAL USING A CARBON-FIBER - COMPOSITE MOLECULAR-SIEVE

Manufacture and characterization of a carbon fiber composite molecular sieve (CFCMS), and its efficacy as a CO2 gas adsorbent are reported. The CFCMS consists of an isotropic pitch derived carbon fiber and a ph enolic resin derived carbon binder. Activation (selective gasification ) of the CFCMS creates microporosity in the carbon fibers, yielding hi gh micropore volumes (>0.5 cm(3)/g) and BET surface areas (>1000 m(2)/ g). Moreover, the CFCMS material is a rigid, strong, monolith with an open structure that allows the free-flow of fluids through the materia l. This combination of properties provides an adsorbent material that has several distinct advantages over granular adsorbents in gas separa tion systems such as pressure swing adsorption (PSA) units. The result s of our initial evaluations of the CO2 adsorption capacity and kineti cs of CFCMS are reported. The room temperature CO2 adsorption capacity of CFCMS is >120 mg of CO2 per g of CFCMS. A proposed project is desc ribed that targets the development, over a three-year period, of a dem onstration separation system based on CFCMS for the removal of CO2 fro m a flue gas slip stream at a coal-fired power plant. The proposed pro gram would be conducted jointly with industrial and utility partners.