Catalytic Methylation of Aromatic Hydrocarbons using CO2/H2 over Re/TiO2 and H-MOR Catalysts

A combined catalyst comprising TiO2-supported Re (Re(1)/TiO2; Re=1 wt%) and H-MOR (SiO2/Al2O3=90) was found to promote the methylation of benzene using CO2 and H-2. This catalytic system exhibited high performance with regard to the synthesis of methylated benzenes and gave high yields of total methylated products (up to 52 % benzene-based yield and 42 % CO2-based yield) under the reaction conditions employed in this study (p(CO2)=1 MPa; p(H2)=5 MPa; T=250 degrees C; t=20 h) in a batch reactor. Catalyst screening demonstrated that a combination of Re(1)/TiO2 and H-MOR (SiO2/Al2O3=90) exhibited superior performance compared to other combinations of supported metal catalysts and zeolites in terms of both yield and selectivity for methylated benzenes.