Adsorption selectivity of CO2 over N2 by cation exchanged zeolite L: Experimental and simulation studies

摘要

CO2 and N2 adsorptionsof alkali and alkaline earth metal cation exchanged zeolite L have beeninvestigated by volumetric measurements and Grand Canonical Monte Carlosimulation. The zeolite KL shows lower degree of exchange because of its uniqueopen-channel framework, linked cancrinite and intercage sites. Structuralcharacteristics have been evaluated using X-ray diffraction analysis andsurface area measurements. CO2 and N2 adsorptionisotherms have been obtained for zeolite KL and its cation exchanged form up to101.3 kPa at 293 and 303 K and the corresponding heats of adsorption estimatedby the Clausius-Clapeyron equation. The experimental results are compared withthose obtained from GCMC simulation. The texture of the materials and theirselectivity for CO2 over N2 adsorption varies with thenature of the exchanged cations. Zeolite-CaL shows remarkably high CO2selectivity (31 times) over N2 amongst the studied alkali andalkaline cation exchanged zeolite L. It has been shown that zeolite L can beused as a potential adsorbent for the removal of CO2 from industrialeffluent gases.