Abstract In the current study, the isomerization of geraniol over a natural sepiolite as a catalyst was investigated and optimized. Prior to application in the isomerization process, the physical and chemical properties of sepiolite were characterized using a battery of instrumental techniques, including XRD, nitrogen adsorption at 77 K, SEM, EDXRF, UV–Vis and FT-IR. Results indicated that geraniol isomerization is very complicated due to the large number of reactions taking place. The catalytic studies showed that the main reaction products were β-pinene, ocimenes, linalool, nerol, citrals, thunbergol and isocembrol; all chemical products with commercial applications. The quantity of each of these products depended on the temperature, catalyst content and reaction time employed in the isomerization process. During the current study, these parameters were varied in a step-wise approach over the ranges 80–150 °C (temperature), 5–15 wt% catalyst content and reaction time of 15–1440 min. As linalool is one of the most commercially important reaction products, the geraniol isomerization method was studied to identify conditions producing the highest selectivity for this compound. The most beneficial conditions for geraniol conversion and linalool formation were established as a temperature of 120 °C, catalyst content of 10 wt% and a reaction time of 3 h. Graphic Abstract

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工艺参数对海泡石异构化香叶醇的影响

摘要 在目前的研究中，以天然海泡石为催化剂对香叶醇异构化进行了研究和优化。在应用于异构化过程之前，海泡石的物理和化学性质使用一系列仪器技术进行表征，包括 XRD、77 K 氮吸附、SEM、EDXRF、UV-Vis 和 FT-IR。结果表明，由于发生大量反应，香叶醇异构化非常复杂。催化研究表明，主要反应产物为β-蒎烯、罗勒烯、芳樟醇、橙花醇、柠檬醛、松柏醇和异辛醇；所有具有商业用途的化学产品。这些产物中的每一种的量取决于异构化过程中使用的温度、催化剂含量和反应时间。在目前的研究中，这些参数在 80–150 °C（温度）、5–15 wt% 催化剂含量和 15–1440 分钟的反应时间范围内逐步变化。由于芳樟醇是商业上最重要的反应产物之一，因此研究了香叶醇异构化方法，以确定对该化合物产生最高选择性的条件。对香叶醇转化和芳樟醇形成最有利的条件是温度为 120 °C，催化剂含量为 10 wt%，反应时间为 3 h。图形摘要 研究了香叶醇异构化方法，以确定对该化合物产生最高选择性的条件。对香叶醇转化和芳樟醇形成最有利的条件是温度为 120 °C，催化剂含量为 10 wt%，反应时间为 3 h。图形摘要 研究了香叶醇异构化方法，以确定对该化合物产生最高选择性的条件。对香叶醇转化和芳樟醇形成最有利的条件是温度为 120 °C，催化剂含量为 10 wt%，反应时间为 3 h。图形摘要