Enhancing the Performance of Vanadium-Phosphorus Oxide (Vpo) Catalysts for N-Butane Oxidation by Tuning the P/V Ratio and Incorporating Y Additives

Abstract

Vanadium-phosphorus oxide (VPO) catalysts are extensively utilized in industrial processes for the selective oxidation of n-butane to maleic anhydride. Despite their industrial success, challenges persist in enhancing n-butane conversion while maintaining high selectivity. To address these challenges, this study synthesized two series of catalysts by varying P/V ratio and incorporating the metal additive Y through an organic synthesis method. Detailed characterization techniques were employed to analyze the structural properties of the catalysts and elucidate the effects of the P/V ratio and Y additives. Specifically, variations in the P/V ratio significantly influence the crystallite size of the catalyst, the specific surface area, the ratio of lattice oxygen to surface oxygen, and the formation of different V5+ species, with the optimum performance obtained at P/V ratio of 0.95. The incorporation of Y additives inhibits grain agglomeration and the formation of VOPO4, and enhances the reducibility of lattice oxygen, thereby increasing the catalytic activity. By elucidating the roles of the P/V ratio and Y additives, this study offers valuable insights for the rational design of more efficient catalytic systems for n-butane oxidation.

Keywords: n-Butane oxidation, VPO catalyst, Y modification, P/V ratio