The adsorption equilibrium and kinetics of CO2, CH4, and N2 on three types of
BETA zeolites were investigated at different temperatures and a defined partial
pressure range from dynamic breakthrough experiments. The adsorbed amount
followed the decreasing order of CO2 >CH4 >N2 for all studied materials. For the
same ratio of SiO2/Al2O3, the Na-BETA-25 zeolite showed a higher uptake capacity
than H-BETA-25, due to the presence of a Na+ cationic center. Comparing the
same H+ compensation cation, zeolite H-BETA-25 expressed a slightly higher
adsorption capacity than H-BETA-150. Regarding the selectivity of gases, based
on their affinity constants, H-BETA-150 displayed the best ability. The adsorption
kinetics was considered using the zero-length-column (ZLC) technique. Response
surface methodology (RSM) was applied to evaluate the interactions between
adsorption parameters and to describe the process.
This work was financially supported by the Project
POCI-01-0145-FEDER-006984, the Associate Laboratory
LSRE-LCM funded by FEDER through COMPETE2020,
Programa Operacional Competitividade e Internacionalização
(POCI), and by national funds through FCT (Fundação para a
Ciência e a Tecnologia). M. Karimi also acknowledges a
research grant awarded under project ‘‘VALORCOMP’’
(ref. 0119_VALORCOMP_2_P), financed through INTERREG
V A Spain Portugal (POCTEP) 2014–2020, under European
Regional Development Fund by FCT. The authors appreciate
Sud-Chemie currently acquired by Clariant International Ltd.
for kindly providing the samples of BETA zeolites studied in
this work.
