Impact of Water Content on UiO-66 Synthesis and Catalyst Activation in Pd/UiO-66 Catalyzed Methyl Nitrite Carbonylation to Dimethyl Carbonate

Due to the modifiable properties and excellent stability, metal-organic frameworks (MOFs) are considered potential catalyst supports in heterogeneous reactions. UiO-66 with varying water contents were synthesized as supports of Pd for the carbonylation of methyl nitrite (MN) to dimethyl carbonate (DMC). In accordance with XRD, NH 3 -TPD, and SEM, the water contents showed a negative correlation on the amounts of acid sites and accelerated crystal aggregation. The Pd/UiO-66(x) demonstrated perfect selectivity of DMC (> 99%) and good CO conversion which were increased with the decrease of water contents. Moreover, the catalysts deactivated at the beginning of the reaction, and the catalytic deactivation was due to the damage of the C = O structure in UiO-66 frameworks. This work revealed the influence of water contents on the synthesis of UiO-66 and the deactivation process of MOF-based catalysts in MN carbonylation to DMC. Graphical