(363d) The Activation of CO2 By UiO-66 MOFs in CO2 Hydrogenation | AIChE

(363d) The Activation of CO2 By UiO-66 MOFs in CO2 Hydrogenation


Jiang, H. - Presenter, Tianjin University
Gao, Q., Virginia Tech
Wang, S., Tianjin University
Chen, Y., Tianjin University
Zhang, M., Tianjin University
As a material with well-ordered tunable porous structures, metal–organic frameworks (MOFs) have advantages such as structural adjustability, large surface area, and excellent gas adsorption capacity. Owing to these properties, the development of MOF materials for CO2 catalytic conversion has attracted tremendous attention.

In this study, UiO-66 and -NH2 modified UiO-66 (named UiO-66-NH2) were synthesized via a hydrothermal method and their activation capacity and hydrogenation catalytic ability of CO2 were investigated. Noticeably, the products of the CO2 hydrogenation reaction over both catalysts were only CO, implying that both MOFs could efficiently activate CO2, but could not hydrogenate the activated CO2 molecule further. More interestingly, although the -NH2 modification brought a new strong base site to UiO-66, which is normally considered an efficient activation site for CO2, UiO-66-NH2 showed a lower activation capacity of CO2 compared to the unmodified UiO-66 (as shown in Table 1). Furthermore, in order to provide dissociated H for the activated CO2 molecules, Pd NPs were selected as the active metal. After the loading of Pd NPs, the Pd@UiO-66 catalyst showed a much higher hydrogenation activity compared to the unloaded UiO-66. The CH4 selectivity, CO2 conversion, and STY of Pd@UiO-66-6% were as high as 97.3%, 56.0%, and 856 g·h-1·kgcat-1, respectively. The good catalytic activity was attributed to the combined effect of high activation capacity of UiO-66 towards CO2 and hydrogen dissociation ability of Pd.

Table 1. The result of CO2 hydrogenation over UiO-66 and UiO-66-NH2


CO2 Conversion











Reaction conditions: 340°C, CO2: H2=1:4 mol, GHSV=15000 h-1, 4 MPa.