Abstract In this article, effects of metallic Fe on biocrude oil production from cornstalk via hydrothermal liquefaction (HTL) in ethanol–water mixed solvents were investigated under various conditions. Experiments were conducted in single solvent of water or ethanol using Fe3O4 catalyst to explore the role of metallic Fe in the liquefaction process. The physiochemical properties of the liquefaction products were comprehensively characterized by elemental analysis, GC–MS, FT-IR and XRD. The results showed that the maximum biocrude oil yield (approx. 50 wt%) and higher heating value (HHV) of 30.86 MJ/kg were obtained in ethanol–water mixed solvents (50/50, v/v) at 300 °C for 30 min with 10 wt% Fe loading. It was found that the presence of Fe also promoted the hydrogenation and deoxygenation of liquid products, obtaining biocrude oils mainly consisted of phenolic, ester and hydrocarbon compounds. The positive role of metallic Fe in HTL of biomass in ethanol–water mixed solvents, simultaneously improving the yield and quality of biocrude oil, was believed to be due to in-situ hydrogen formed from the reaction of metallic Fe and water, while the generated Fe3O4 exhibited negligible catalytic effect in the process.

中文翻译：

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金属铁对乙醇-水混合溶剂中玉米秸秆水热液化生产生物原油的促进作用

摘要 本文研究了金属铁在不同条件下对乙醇-水混合溶剂中水热液化 (HTL) 玉米秸秆生物原油生产的影响。实验在水或乙醇的单一溶剂中使用 Fe3O4 催化剂进行，以探索金属 Fe 在液化过程中的作用。通过元素分析、GC-MS、FT-IR和XRD对液化产物的理化性质进行了综合表征。结果表明，在 300 °C 的乙醇-水混合溶剂 (50/50, v/v) 中，生物原油产量最大（约 50 wt%）和更高的热值（HHV）为 30.86 MJ/kg。 30 分钟，含 10 wt% Fe。发现Fe的存在也促进了液体产物的加氢和脱氧，获得的生物原油主要由酚类、酯类和烃类化合物组成。金属铁在乙醇-水混合溶剂中生物质 HTL 的积极作用，同时提高生物原油的产量和质量，被认为是由于金属铁和水反应形成的原位氢，而产生的Fe3O4 在该过程中表现出可忽略不计的催化作用。