Physicochemical Studies of Ni-, Co-, and Pt- Promoted Movnbox Catalysts Synthesised by Impregnation Method

Ni-, Co-, and Pt- promoted MoVNbOx mixed metal oxide catalysts were prepared by impregnation method. The physicochemical properties of the catalysts showed that the BET surface area of the promoted catalysts was lower when compared to the unpromoted catalysts due to the filling of open pores by the promoters. X-ray diffraction (XRD) analysis indicated that the main reflections were consistent with the tetragonal rutile structure. Three crystalline phases of (V0.07Mo0.93) 5 O14, (Nb0.09Mo0.91)O2.80, and Mo4 O11 could also be observed. Induced Coupled PlasmaOptical Emission Spectroscopy (ICP-OES) displayed the loss of metal promoters, mainly due to sublimation during calcination with Pt-MoVNbOx. Temperature Programmed Reduction (H2 -TPR) exhibited high reducibility for samples loaded with 10-3 wt% promoter. The level of reduction declines with increased loads, suggesting a stronger oxygen bond in the promoted metal oxide catalysts.