Abstract Ultrasonic as a fast and powerful method was applied to prepare dendritic fibrous nanosilica (DFNSU) and the properties of this silica were compared with those of DFNS prepared by hydrothermal method (DFNSH). Using this support, a series of the Zn/DFNSU catalysts were prepared by incorporation of different zinc values using the co-condensation technique. The prepared catalysts were characterized by various methods (FT-IR, XRD, ICP, SEM, TEM, BET, and Py-FT-IR) and applied for direct production of hexyl levulinate from glucose. Among these catalysts, 40Zn/DFNSU exhibited the best results for the production of hexyl levulinate with 55.2% yield under optimum reaction conditions (0.05 g catalyst, 0.07 g glucose, reaction temperature of 200 °C and reaction time of 5 h). Also, the catalytic performance of Zn/DFNSH catalysts with different zinc values was studied under optimum reaction conditions and the maximum yield of hexyl levulinate was 59.2% in the presence of 40Zn/DFNSH catalyst.

中文翻译：

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改性树枝状纤维纳米二氧化硅催化葡萄糖直接生产乙酰丙酸己酯作为潜在的燃料添加剂

摘要 超声波作为一种快速而有效的方法被用于制备树枝状纤维状纳米二氧化硅（DFNSU），并将这种二氧化硅的性能与水热法制备的DFNS（DFNSH）进行了比较。使用这种载体，通过使用共缩合技术掺入不同的锌值，制备了一系列 Zn/DFNSU 催化剂。制备的催化剂通过各种方法（FT-IR、XRD、ICP、SEM、TEM、BET 和 Py-FT-IR）进行表征，并用于从葡萄糖直接生产乙酰丙酸己酯。在这些催化剂中，40Zn/DFNSU在最佳反应条件（0.05 g催化剂，0.07 g葡萄糖，反应温度200°C，反应时间5 h）下以55.2%的收率生产乙酰丙酸己酯的最佳结果。还，