Oxide-Supported Tetraethylenepentamine for CO_2 Capture

摘要

CO_2 capture capacity of tetraethylenepentamine (TEPA) supported on beta zeolite, SiO_2, and Al_2O_3 has been studied by transient flow switching approach and temperature programmed desorption (TPD) technique coupled with diffuse infrared reflectance Fourier transform spectroscopy and mass spec-trometry (MS). TEPA/beta zeolite shows the highest CO_2 capture capacity. Adsorbed CO_2 on TEPA/beta zeolite can be characterized as weakly and strongly adsorbed CO_2. The former desorbs when CO_2 partial pressure decreases; the latter desorbs during TPD. Strongly adsorbed CO_2 is in the form of carbonates interacting with the N-H functional groups of TEPA. This interaction caused the N-H and C-H intensity to decrease. TEPA/Al_2O_3 showed the lowest CO_2 capture capacity. The infrared results revealed that TEPA/Al_2O_3 possessed high content of H_2O, which inhibited CO_2 adsorption.