Abstract: | Palladium containing EMT zeolite catalyst(Pd/EMT) was prepared and used for the indirect oxidative carbonylation of methanol to dimethyl carbonate(DMC).The EMT zeolite was employed as a new catalyst support and compared with the conventional Pd containing FAU zeolite catalyst(Pd/FAU).The Pd/EMT in contrast to the Pd/FAU catalyst exhibited high intrinsic activity with the turnover frequency of 0.25 s~(-1) vs.0.11 s~(-1).The Pd/EMT catalyst showed high CO conversion of 82% and DMC selectivity of 79%,that maintained for at least 130 h,while the activity of the Pd/FAU catalyst rapidly deteriorated within 12 h.The enhanced interactions between Pd and EMT zeolite inhibited the sintering of palladium clusters and maintained the Pd~(2+) active sites in the Pd/EMT catalyst.The stabilization of the mono-dispersed Pd clusters within the EMT zeolite is paramount to the excellent performance of the catalyst for the indirect oxidative carbonylation of methanol to DMC. |