CALF-20 obtained by mechanochemical synthesis for temperature swing adsorption CO2 Capture: A thermodynamic and kinetic study

This study examines the potential of CALF-20, a zinc-based metal–organic framework (MOF), synthesized through mechanochemistry, for carbon dioxide (CO2) capture using temperature swing adsorption (TSA) in postcombustion processes. Unlike conventional methods, mechanochemical synthesis reduces solvent usage and reaction time, aligning with sustainability goals while preserving the structural integrity of CALF-20. This research investigates CALF-20 thermodynamic and kinetic properties, assessing its CO2 adsorption and desorption performance within a laboratory-scale fixed-bed reactor under various operational temperatures (28–130 ◦C) and CO2 concentrations (3–20 % by volume). Key findings reveal that CALF-20 displays promising CO2 adsorption and desorption efficiency, achieving complete regeneration in each cycle. Sips isotherm analysis demonstrates a high CO2 adsorption capacity (up to 2.55 mmol g–1) and surface heterogeneity, while isosteric heat of adsorption values confirm a physisorption-driven process. Kinetic analysis shows that the pseudo-firstorder model fits the CO2 adsorption data best, further confirming a primarily physical adsorption mechanism. Additionally, the study demonstrates the stable performance of CALF-20 across ten TSA cycles, underscoring its potential as a viable and sustainable material for CO2 capture applications.