Model Number |
KAR-F33 |
Product Name |
CALF-20 |
Particle size |
1~5 μm |
Specific surface area |
≥400 ㎡/g |
Pore size |
0.3~0.5 nm |
CALF-20 has a high CO2 adsorption capacity due to the attractive dispersion interactions between CO2 and the MOF structure. Previous studies have reported that CALF-20 exhibits good selectivity for CO2/N2 systems. In addition, CALF-20 showed lower H2O loading at low relative humidity compared to zeolite 13X, which has been practically used as a CO2 adsorbent in industrial fields but adsorbs large amounts of H2O in the pores.
Therefore, CALF-20 is expected to replace zeolites in adsorbing CO2 even in the presence of H2O because the flue gas emitted from power plants and atmospheric air containing moisture decrease the CO2 adsorption performance of adsorbents. In addition, interestingly, a previous report mentioned that the crystal structure of CALF-20 changes with increase in the relative humidity. Oxalate ligands changed from bis-bidentate to monodentate and then the distance between a zinc ion and an oxygen constituting oxalate increased from 2.20 to 2.31 Å.
On the other hand, it's been investigated the Xe adsorption performance of CALF-20 and revealed that CALF-20 showed good Xe separation selectivity for Xe/Kr and Xe/N2 systems due to van der Waals interaction between Xe and C-H groups of 1,2,4-triazolate. In addition, CALF-20 exhibited high adsorption performance for SO2 and Cl2, which have large van der Waals surface interacting with MOF surface, at low pressure side. On the other hand, the researchers reported that CALF-20 showed a high electrochemical reduction performance of CO2 to CO due to the charge transfer effect between oxalate and triazolate constituting CALF-20. Given the reports, CALF-20 has possibilities to be applied to gas adsorbents and catalysts for CO2 reduction reactions.