Dual-bed CO, adsorption using zeolite was studied experimentally and theore
tically. Boiler exhaust gas (13 vol% CO2, 79 vol% N-2 and 8 vol% O-2) was u
sed as a feed gas for the eight-step four-bed PSA process. Na-X type zeolit
e (NaX) and Na-A type zeolite (NaA) were selected in the break-through test
. NaX has higher CO2 adsorption capacity than other adsorbents. NaA has the
highest selectivity among all adsorbents tested. In the simulations, a NaX
-to-NaA ratio affected the recovery efficiency and the concentration of rec
overy gas. Moreover, in the dual-bed PSA process of NaX-to-NaA ratio = 2/1,
the recovery efficiency and CO2 concentration of recovery gas were higher
than those in a sin.-le-adsorbent PSA process. Simulated results by the dyn
amic model agreed well with the PSA experimental results. (C) 2001 Elsevier
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