Abstract: The high specific surface area VPOcata1yst systems were first developed by using polyethyleneglycol(PEG) as the dispersant in the organic media.Two PEGs with different molecular weights, namely,PEG 6000 and PEG 10000, were applied to this study, and the resulted VPOcatalyst had their specificsurface areas of 52 and 54 m²/g, respectively.For the VPOsample prepared without using PEG, it onlyhad a specific surface area of 19 m²/g.For partial oxidation of n-butane to maleic anhydride, it was foundthat the conversion of n-butane and the selectivity to maleic anhydride over the catalysts prepared in thepresence of PEGwere 84%-87% and 78%, respectively; while over the compared sample they are only 71% and 71%, respectively.The significant higher specific surface area of the PEG-synthesized samplemay in part account for the enhancement in catalytic activity.

Key words: VPO catalysts, Polyethylene glycol, High specific surface area, Preparation chemistry