Mercury removal from flue gas using UiO-66-type metal-organic frameworks grafted with organic functionalities

UiO-66-type metal-organic frameworks (MOF) grafted with organic functionalities (-Br, -NO2 and -NH2) are introduced to investigate the elemental mercury (Hg-0) removal from flue gas, and the effect for adding linkers on Hg-0 removal is discussed. Results indicated that added functional groups did not alter the original topology of adsorbents, although their size and morphology varied. Adding -NH2 and -NO2 functional groups was detrimental for the thermal stability of UiO-66 except for -Br functional group, and grafted-Br itself was also stable. The Hg-0 removal ability of UiO-66 was not significantly changed by grafting -NH2 and -NO2. The grafted-Br was beneficial for Hg-0 capture, and the Hg-0 removal performance of UiO-66-Br increased with increasing oxygen content and temperature. Furthermore, the mechanism of Hg-0 capture was studied.

Automated summary

By introducing UiO-66-type MOFs grafted with different organic functionalities, the impact of -NH2, -NO2, and -Br on Hg-0 removal was compared. It was found that -NH2 and -NO2 were detrimental to the thermal stability of UiO-66, while -Br was beneficial for Hg-0 capture.