Synthesis and adsorption investigations of zeolites MCM-22 and MCM-49 modified by alkali metal cations

摘要

Ion exchange was made on MCM-22 and MCM-49 zeolites with different Si/Al molar ratios,with Li~+,Na~+,K~+,and Cs~+ions and the study of the influence of alkali metal cations on CO2 adsorption properties was performed.The degree of ion-exchange decreased for larger cations (Cs~+) apparently due to steric hindrances.The exchange with different cations led to a decrease in the surface area and the micropore volume.Our study shows that the adsorption capacity of the tested zeolites depends significantly on the nature and the concentration of the charge-compensating cations.The highest CO2 adsorption capacity was obtained on the MWW zeolites with the lowest Si/Al molar ratio and the Li~+or K~+cations.