CATALYTIC ACTIVITY OF RUTHENIUM PROMOTED CO-MO/AL2O3 AND INFRARED INVESTIGATION OF CARBON-MONOXIDE AND NITRIC-OXIDE ADSORPTION

The conversion of thiophene to hydrocarbons and of cyclohexene to cyclohexane over Ru-Co-Mo/Al2O3 and Co-Mo/Al2O3 as well as Ru/Al2O3 catalysts has been performed, and it was found that the Ru-Co-Mo/Al2O3 catalyst exhibited higher catalytic activities than the Co-Mo/Al2O3 and Ru/Al2O3 catalysts, showing that Ru had a remarkable promotion effect increasing HDS and HYD activities. IR studies on the reduced and sulfided Ru-Co-Mo/Al2O3 showed that the characteristic band intensities of CO and NO adsorbed on Co and Mo sites increased significantly and that the frequencies of these adspecies displayed a bathochromic shift, as compared with the Co-Mo/Al2O3. Furthermore, experimental TPD-IR data showed different desorption temperature and amount of adsorbed NO and CO adspecies between the reduced Ru-Co-Mo/Al2O3 and the reduced Co-Mo/Al2O3. These results suggested that there was an interaction between Ru sites and Mo (Co) sites in both reduced and sulfided Ru-Co-Mo/Al2O3 catalysts, which was probably related to electron transference from Ru to Mo (Co) sites