Abstract

In the present study, optimal reaction conditions to produce levulinic acid (LA) from depithed sugarcane bagasse (DSB) using 1-ethyl-3-methylimidazolium hydrogen sulfate [EMim][HSO₄] ionic liquid (IL) were investigated. The effect of temperature (100–220 °C), reaction time (2–12 h), and ionic liquid loading (1–4 g) was assessed using response surface methodology based on the Box-Behnken design. The optimum conditions were found to be 100 °C, 7 h, and 4 g of IL, which yielded 54.6% of LA from DSB. The analysis of variance (ANOVA) indicated that the design model was significant at the 95% confidence level. The pareto chart revealed that IL loading had the most significant effect on the production of LA, followed by temperature and reaction time. The P-values also showed that these were the significant model terms. There is a strong correlation between temperature and IL loading. Solvent optimization revealed that the type of solvent used in the LA production has a significant effect on LA yield. Water was used as the control solvent for this study. Methyl isobutyl ketone (MIBK) yielded the highest LA (62%) from all the solvents that were used.

Graphic Abstract

中文翻译：

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1-乙基-3-甲基咪唑硫酸氢盐[EMim] [HSO 4]中深度发酵的甘蔗渣中生产乙酰丙酸的工艺优化

摘要

在本研究中，使用1-乙基-3-甲基咪唑硫酸氢盐[EMim] [HSO ₄ ]从深度发酵的甘蔗渣（DSB）中生产乙酰丙酸（LA）的最佳反应条件研究了离子液体（IL）。使用基于Box-Behnken设计的响应面方法，评估了温度（100–220°C），反应时间（2–12 h）和离子液体载量（1-4 g）的影响。发现最佳条件是100°C，7 h和4 g IL，从DSB产生LA的54.6％。方差分析（ANOVA）表明，该设计模型在95％的置信水平下具有显着性。对比图显示，IL负载对LA的产生影响最大，其次是温度和反应时间。P值还表明这些是重要的模型项。温度和IL负载之间存在很强的相关性。溶剂优化表明，在LA生产中使用的溶剂类型对LA产量有重大影响。水用作该研究的对照溶剂。甲基异丁基酮（MIBK）从所有使用的溶剂中产生最高的LA（62％）。

图形摘要