Zirconium fumarate-based sorbents for CO2 capture: synthesis, characterization and performance evaluation

This study includes the preparation of zirconium fumarate (ZrFu)-based porous metal-organic frameworks (MOFs) and investigation of the CO2 capture performance of the materials using a tubular flow reactor. To enhance the CO2 capture capacity of the MOFs, monoethanolamine (MEA) and tetraethylenepentamine molecules were incorporated by two different methods, namely wet-impregnation and in-situ grafting methods. Several analysis techniques were adopted to characterize the materials. The effect of temperature, amine type, and amine loading on CO2 sorption was examined explicitly. The in-situ amine-grafted materials showed better CO2 capture performance than the wet-impregnated amine-modified samples. The obtained value of the CO2 uptake capacity of the pristine ZrFu is 74 g CO2 kg−1 sorbent at 30°C. Among the amine-modified MOFs, the in-situ grafted MEA-modified zirconium fumarate showed the maximum adsorption capacity (85 g CO2 kg−1). The synthesized MOFs exhibited commendable thermal and chemical stability up to around 200°C.