Adsorptive filtration of carbon dioxide from wet gases utilizing microfibrous filter media entrapped K₂CO₃

Present commercial CO₂ removal units utilize a physical solvent of alkanolamine, such as MEA, diethanolamine, and methyldiethanolamine. A microfibrous entrapped sorbent was developed for CO₂ removal from flue gas. A microfibrous carrier consisting of 4 and 8 μm (dia) metal fibers was utilized to entrap 150-250 μm (dia) activated carbon particulates (ACP). K₂CO₃ was then loaded onto the support by pseudo-incipient wetness at various loadings by varying the solution concentration. The adsorption capacity of CO₂ at various K₂CO₃ loadings was studied. The nano-dispersed nature of K₂CO₃ combined with the use of small support particulates promoted high K₂CO₃ utilization, high contacting efficiency, and high accessibility of K₂CO₃. At equivalent bed volumes, K₂CO₃/ACP entrapped materials provided longer breakthrough times for CO₂ removal compared to packed beds of K₂CO₃ pellets. At 87% relative humidity, maximum capacity at room temperature based on total weight of adsorbents was ∼ 0.037 g CO₂ with optimal loading of 30 wt % K₂CO₃ for packed beds corresponding to 33% utilization of impregnated K₂CO₃. This is an abstract of a paper presented at the AIChE Annual Meeting and Fall Showcase (Cincinnati, OH 10/30/2005-11/4/2005).