Abstract The use of lignocellulosic biomass as a raw material can sustain the chemical industry. There is a lack of knowledge in kinetics and thermodynamics of some of these processes, making difficult the cost analysis. For instance, the thermodynamic investigation of the hydrogenation of alkyl levulinates to γ-valerolactone (GVL) is seldom. This system is a two-step reaction comprising a hydrogenation and cyclization step. The experimental measurement of the two reaction enthalpies is challenging, and a method was developed in this manuscript. The hydrogenation of methyl levulinate (ML) and butyl levulinate (BL) in the GVL solvent was found to be an exothermic step, and the cyclization an endothermic one. The reaction enthalpy for the hydrogenation of ML in the GVL solvent, calculated to -53.25 kJ/mol, is higher than the one of BL in the GVL solvent, calculated to -38.66 kJ/mol. The reaction enthalpies for the cyclization step are similar for ML and BL system, i.e., +7.00 kJ/mol and +6.50 kJ/mol, respectively. Hence, the hydrogenation step governs the reaction temperature. A thermal risk assessment based on experiments performed under adiabatic condition was done. The thermal risk was found to be medium for this reaction system under the operating conditions used in this study.

中文翻译：

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从量热法到热风险评估：乙酰丙酸烷基酯氢化产生 γ-戊内酯

摘要 使用木质纤维素生物质作为原料可以维持化学工业的发展。其中一些过程缺乏动力学和热力学知识，这使得成本分析变得困难。例如，乙酰丙酸烷基酯氢化为γ-戊内酯（GVL）的热力学研究很少。该系统是包括氢化和环化步骤的两步反应。两种反应焓的实验测量具有挑战性，本手稿开发了一种方法。发现乙酰丙酸甲酯 (ML) 和乙酰丙酸丁酯 (BL) 在 GVL 溶剂中的氢化是放热步骤，环化是吸热步骤。ML 在 GVL 溶剂中加氢的反应焓，计算为 -53.25 kJ/mol，高于 GVL 溶剂中的 BL 之一，计算为 -38.66 kJ/mol。ML和BL系统的环化步骤的反应焓相似，即分别为+7.00 kJ/mol和+6.50 kJ/mol。因此，氢化步骤控制反应温度。进行了基于在绝热条件下进行的实验的热风险评估。在本研究中使用的操作条件下，发现该反应系统的热风险为中等。