Abstract Hydrothermal liquefaction (HTL) is considered as a promising thermochemical conversion technology for crude bio-oil (biocrude) production from biomass. However, the influence of downstream processing methods (such as biocrude recovery methods and solvents used) has not been investigated fully to date. In this investigation we examined the effect of solvents and extraction methods on the yield and physiochemical properties of biocrude from Chlorella sp. (C. sp.), spent coffee grounds (SCG), and a mixture of the two. It was found that the extraction method did not have a significant effect on the yield and physiochemical properties of biocrude derived from the feedstock of interest in this study. However, the solvents used for biocrude recovery had crucial effects, in which dichloromethane (DCM) was determined to the most favorable one from biocrude yield and chemical yield perspective. It was also noticed that the synergetic effects claimed for co-liquefaction of C. sp. and SCG were highly dependent on the solvent used to recover bio-crude. Overall, it is expected that this study could attract more attention on the impact of various recovery procedures on the yield/physiochemical properties of bio-oil resulting from hydrothermal liquefaction processes.

中文翻译：

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下游加工方式对热液液化生物油产率及理化性质的影响

摘要 水热液化（HTL）被认为是一种有前景的热化学转化技术，用于从生物质中生产粗生物油（生物原油）。然而，下游加工方法（如生物原油回收方法和使用的溶剂）的影响迄今尚未得到充分研究。在这项研究中，我们检查了溶剂和提取方法对小球藻生物原油产量和理化性质的影响。(C. sp.)、废咖啡渣 (SCG) 以及两者的混合物。发现提取方法对源自本研究中感兴趣的原料的生物原油的产量和理化性质没有显着影响。然而，用于生物原油回收的溶剂具有至关重要的影响，其中，从生物原油收率和化学收率的角度来看，二氯甲烷 (DCM) 被确定为最有利的一种。还注意到 C. sp. 的共液化所声称的协同效应。和 SCG 高度依赖于用于回收生物原油的溶剂。总体而言，预计这项研究可以吸引更多关注各种回收程序对水热液化过程产生的生物油产量/理化性质的影响。