Abstract Biodiesel is a clean and renewable energy. In this study, biodiesel was produced through the esterification of free fatty acid (FFA) with methanol over the high silica B-ZSM-5 nanocatalyst. The parent nanocatalyst was synthesized by hydrothermal technique and the promoter was introduced by a multi-step wet impregnation method. XRD, FT-IR, BET, FE-SEM, EDX, TEM, and NH3-TPD analyzes characterized the textural and acidity properties of the nanocatalysts. The promoter was dispersed uniformly without significant framework destruction. The impregnation of molybdenum decreased the strength of the acid sites and increased the concentration of the acid sites. The morphology of the nanocatalyst was spherical including the high crystallinity, high surface area, and mesoporous structure. The 25% MoO3/B-ZSM-5 nanocatalyst showed the best performance in the esterification of FFA. The optimum operating conditions were 6 h reaction time, temperature of 160 °C, 3%wt catalyst concentration, and methanol/FFA molar ratio of 20:1, which resulted in the highest conversion of FFA (98%). The impregnated nanocatalyst had high stability and reusability through the sequence runs including only 5% conversion drop after six runs. The results confirmed the high potential of the developed nanocatalyst for industrial applications.

中文翻译：

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钼助剂对高二氧化硅MoO3/B-ZSM-5纳米催化剂在生物柴油生产中性能的影响

摘要 生物柴油是一种清洁的可再生能源。在这项研究中，生物柴油是通过游离脂肪酸 (FFA) 与甲醇在高二氧化硅 B-ZSM-5 纳米催化剂上的酯化来生产的。母体纳米催化剂采用水热法合成，助催化剂采用多步湿法浸渍法引入。XRD、FT-IR、BET、FE-SEM、EDX、TEM 和 NH3-TPD 分析表征了纳米催化剂的结构和酸度特性。促进剂均匀分散，没有明显的骨架破坏。钼的浸渍降低了酸位的强度并增加了酸位的浓度。纳米催化剂的形态为球形，包括高结晶度、高表面积和介孔结构。25% MoO3/B-ZSM-5 纳米催化剂在 FFA 的酯化中表现出最好的性能。最佳操作条件是反应时间为 6 h，温度为 160 °C，催化剂浓度为 3%wt，甲醇/FFA 摩尔比为 20:1，这导致 FFA 的转化率最高（98%）。浸渍的纳米催化剂在整个序列运行中具有高稳定性和可重复使用性，包括六次运行后转化率仅下降 5%。结果证实了所开发的纳米催化剂在工业应用中的巨大潜力。浸渍的纳米催化剂在整个序列运行中具有高稳定性和可重复使用性，包括六次运行后转化率仅下降 5%。结果证实了所开发的纳米催化剂在工业应用中的巨大潜力。浸渍的纳米催化剂在整个序列运行中具有高稳定性和可重复使用性，包括六次运行后转化率仅下降 5%。结果证实了所开发的纳米催化剂在工业应用中的巨大潜力。