Highly active Pd containing EMT zeolite catalyst for indirect oxidative carbonylation of methanol to dimethyl carbonate

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 Pd2+ 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.