Synthesis and CO2 adsorption kinetics of Aluminum Fumarate MOFs pellet with high recovery

As a promising CO 2 adsorbent, Aluminum Fumarate (AlFu) metal organic frameworks (MOFs) were explored for pelletizing technology and CO 2 adsorption characteristics. The effects of binder type (sodium carboxymethylcellulose (CMC), aluminum sol (AS)) and content (2.5 wt%-20 wt%), CO 2 partial pressure (0.3 bar–1 bar) and temperature (35 °C–65 °C) on the mechanical performance and adsorption process were investigated. The results revealed that with the increase of binder mass, the pellet mechanical strength rose while the CO 2 adsorption amount decreased. The AlFu pellet with 2.5 wt% CMC could retain the powder porosity and adsorption capacity . The mechanical strength of AlFu@CMC-2.5 wt% achieved 1.486 MPa, and the maximum adsorption capacity was 1.26 mmol/g at 35 °C and 1.0 bar. The CO 2 adsorption capacity was increased with lower adsorption temperature and higher CO 2 partial pressure. Compared with pseudo second order model and pseudo first order kinetic model , Avrami kinetic model could better describe the CO 2 adsorption behavior of AlFu pellet. It indicated that the adsorption process was not a single physical or chemical adsorption . The rate-limiting kinetic analysis showed that the CO 2 adsorption rate was determined by film diffusion and intraparticle diffusion rather than inter-particle diffusion.