Abstract
A combination of gas adsorption and gas breakthrough measurements show that the metal-organic framework, Al(HCOO)(3) (ALF), which can be made inexpensively from commodity chemicals, exhibits excellent CO(2) adsorption capacities and outstanding CO(2)/N(2) selectivity that enable it to remove CO(2) from dried CO(2)-containing gas streams at elevated temperatures (323 kelvin). Notably, ALF is scalable, readily pelletized, stable to SO(2) and NO, and simple to regenerate. Density functional theory calculations and in situ neutron diffraction studies reveal that the preferential adsorption of CO(2) is a size-selective separation that depends on the subtle difference between the kinetic diameters of CO(2) and N(2). The findings are supported by additional measurements, including Fourier transform infrared spectroscopy, thermogravimetric analysis, and variable temperature powder and single-crystal x-ray diffraction.