SEPARATION OF CARBON-DIOXIDE BY PRESSURE SWING ADSORPTION USING GRANULAR MOLECULAR-SIEVING CARBON

Using granular molecular sieving carbon (MSC) produced from polyvinyl alcohol (PVA)/phenolic resin, measurements of adsorption equilibria and adsorption rates of single-component systems of N2 and CO2 were carried out. The amount of CO2 adsorbed on the MSC was larger than that of N2 at equilibrium, and the MSC had a higher diffusivity ratio of CO2 to N2 than did the active carbon. In addition, an experiment on CO2 separation from a mixed gas of N2/CO2/H2O by the pressure swing adsorption (PSA) method using the MSC was carried out. The following results were obtained. 1) CO2, of which the concentration was 15 vol. %, was concentrated to a maximum value of 68 vol. % under a CO2 yield of more than 0.96. There was no significant effect of water vapor content in the feed gas on the CO2 separation capabilities. 2) The adsorption cycle time and the waste gas flow rate significantly affected CO2 separation by the PSA method. The temperature changes in an adsorption column supported this conclusion.