Hierarchical Catalysts Based on Cerium(IV) Oxide for Direct Synthesis of Dimethyl Carbonate

Hierarchical oxides based on CeO 2 and Al 2 O 3 were prepared by the sol-gel method and were characterized by SEM, low-temperature nitrogen adsorption–desorption, X-ray diffraction analysis, and in situ Raman spectroscopy. The samples had the specific surface area of up to 200 m 2 /g with the pore size from 2 to 40 nm. They were tested in the synthesis of dimethyl carbonate from carbon dioxide and methanol. The samples with different cerium content differ in the pore structure characteristics and catalytic properties. Pure cerium(IV) oxide is the most active and exhibits 100% selectivity with respect to dimethyl carbonate. The optimum reaction conditions are 130°С and a pressure of 5 MPa.