Furfural is an industrial renewable platform chemical, which can be converted to useful furanics such as α-angelica lactone, carboxylic acids such as levulinic acid and valeric acid, or to higher carbon content products via condensation routes for producing drop-in fuel replacements and chemicals with diverse applications. These important conversion processes may be carried out in selective fashions, although they require adequate catalysts. They were successfully carried out using versatile, stable silica-wrapped niobium oxide nanostructured catalysts. For example, α-angelica lactone was converted in an integrated fashion to ethyl levulinate in 90% yield, and the esterification of levulinic and valeric acids gave ethyl levulinate in quantitative yield and ethyl valerate in 90% yield, respectively, at 140 °C. Catalytic, mechanistic and kinetic modelling studies shed light on the influence of the materials properties on the catalytic performances. These catalysts outperformed pure Nb₂O₅, as well as hydrothermally synthesized composites consisting of Nb₂O₅ nanoparticles embedded in a mesoporous siliceous matrix.

中文翻译：

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通过铌基催化剂对生物质衍生的呋喃和羧酸进行化学增值

糠醛是一种工业可再生平台化学品，可以转化为有用的呋喃，如 α-当归内酯，羧酸，如乙酰丙酸和戊酸，或通过缩合路线转化为更高碳含量的产品，用于生产直接替代燃料和化学品具有多样化的应用。这些重要的转化过程可以以选择性的方式进行，尽管它们需要足够的催化剂。他们使用多功能、稳定的二氧化硅包裹的氧化铌纳米结构催化剂成功地进行了实验。例如，α-当归内酯以90%的收率整体转化为乙酰丙酸乙酯，乙酰丙酸和戊酸的酯化分别在140℃下定量生成乙酰丙酸乙酯和90%的戊酸乙酯。催化、机械和动力学建模研究揭示了材料特性对催化性能的影响。这些催化剂的性能优于纯Nb ₂ O ₅以及由嵌入介孔硅质基质中的Nb ₂ O _{5纳米颗粒组成的水热合成复合材料。}