CALF-20 obtained by mechanochemical synthesis for temperature swing adsorption CO2 Capture: A thermodynamic and kinetic study
Federica Raganati, Mariangela Bellusci, Francesco Leardi, Francesca Varsano, Paola Ammendola
Abstract
• CALF-20 is synthesized sustainably via a reduced-solvent mechanochemical method. • CALF-20 was tested under dynamic conditions in a lab-scale fixed-bed reactor. • CALF-20 achieves high CO 2 adsorption capacity of up to 2.55 mmol g –1 in TSA tests. • CALF-20 shows stable multi-cyclic performance over multiple TSA cycles. • Thermodynamic and kinetic studies confirm a physisorption-driven capture process. This study examines the potential of CALF-20, a zinc-based metal–organic framework (MOF), synthesized through mechanochemistry, for carbon dioxide (CO 2 ) capture using temperature swing adsorption (TSA) in post-combustion 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 CO 2 adsorption and desorption performance within a laboratory-scale fixed-bed reactor under various operational temperatures (28–130 °C) and CO 2 concentrations (3–20 % by volume). Key findings reveal that CALF-20 displays promising CO 2 adsorption and desorption efficiency, achieving complete regeneration in each cycle. Sips isotherm analysis demonstrates a high CO 2 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-first-order model fits the CO 2 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 CO 2 capture applications.