Maleic anhydride (MA) is a significant chemical raw material to produce industrial products. Vanadium phosphorus oxide (VPO) catalyst is considered an excellent catalyst for the selective oxidation of n-butane to prepare MA. However, MA selectivity is still limited by the complex crystalline phases and morphological characteristics of VPO catalysts. Herein, orthorhombic Sb₂O₃ was proposed as a structural directing agent and electronic promoting agent to modify the VPO catalyst. The relationship between the structure and the catalytic performance was systematically investigated to reveal the effect of orthorhombic Sb₂O₃. Physical characterizations reveal the introduced orthorhombic Sb₂O₃ greatly contributes to improving the active phases and inhibiting the disadvantageous δ-VOPO₄ phase. Besides, the active phase and surface chemical properties of the VPO catalyst are effectively regulated, which is beneficial to the selective oxidation of n-butane. As expected, the optimal 1Sb₂O₃–O@VPO catalyst demonstrates considerable n-butane conversion, MA selectivity, and MA yield. This work should open a feasible way to prepare efficient VPO catalysts for industrial catalysis.

中文翻译：

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Sb2O3 改性钒磷氧化物催化剂调节马来酸酐对正丁烷氧化的选择性


马来酸酐（MA）是生产工业产品的重要化工原料。钒磷氧化物（VPO）催化剂被认为是正丁烷选择性氧化制备MA的优异催化剂。然而，MA选择性仍然受到VPO催化剂复杂的晶相和形态特征的限制。本文提出正交晶系Sb ₂ O ₃ 作为结构导向剂和电子促进剂来改性VPO催化剂。系统地研究了结构与催化性能之间的关系，揭示了斜方晶系Sb ₂ O ₃ 的影响。物理表征表明，引入的斜方Sb ₂ O ₃ 极大地有助于改善活性相并抑制不利的δ-VOPO ₄ 相。此外，VPO催化剂的活性相和表面化学性质得到有效调节，有利于正丁烷的选择性氧化。正如预期的那样，最佳的 1Sb ₂ O ₃ –O@VPO 催化剂表现出相当大的正丁烷转化率、MA 选择性和 MA 产率。这项工作为制备用于工业催化的高效 VPO 催化剂开辟了一条可行的途径。