Conversion of ethane into benzene on Mo2C/ZSM-5 catalyst Original Research Article

The reaction of ethane on unsupported and supported molybdenum compounds has been investigated at 773–973 K. ZSM-5 was used as support. Reaction products were analyzed using gas chromatography. Changes in the composition of catalyst samples were followed by X-ray photoelectron spectroscopy. Unsupported MoO3 is partially reduced with ethane above 800 K to give H2O and CO2. The formation of H2, C2H4 and CH4 was also observed. Mo-free ZSM-5 exhibited relatively high activity towards dehydrogenation, hydrogenolysis and aromatization of ethane above 773 K. Deposition of MoO3 on ZSM-5 significantly enhanced the conversion of ethane and also the selectivity of benzene production. Alteration of the catalytic behaviour of MoO3/ZSM-5 in time on-stream at 773–973 K was attributed to the reaction of MoO3, to carbon deposition and to the formation of Mo2C. Unsupported Mo2C catalyzed the dehydrogenation of ethane without producing benzene. In contrast, Mo2C/ZSM-5 was found to be an effective catalyst in the aromatization of ethane. At 973 K the conversion of ethane was ∼67% and the selectivity to benzene formation 31%.