As a zero-carbon energy source, biomass will play an important role in achieving the goal of carbon neutrality. The efficient conversion and utilization of biomass energy remains a great challenge. Thermochemical liquefaction is one of the most efficient ways to convert biomass into liquid fuels. In this study, five different solvents were used to liquefy sawdust. The results showed that cyclohexanol had the highest conversion of 90.5% with a liquid yield of 79.1%, followed by tetralin (81.7% and 72.0%), ethanol (70.2% and 57.0%), isopropanol (64.5% and 47.7%), and cyclohexane (57.0% and 44.5%). The better performance of cyclohexanol and tetrahydrofuran is due to their greater mass and heat transfer capacity, which is determined by the comparative solvent properties. The liquefied gas, liquid and solid products were characterized by GC, GC-MS and FT-IR, respectively. The results demonstrated that the composition of hydrogen and hydrocarbons in the gas was influenced by the hydrogen donor of the solvent; the distribution of bio-oil was strongly influenced by the hydrogen donor and side reactions of the solvent; the solid residue was mainly from lignin in the wood chip composition. In addition, microcrystalline cellulose and lignin were used as models to further investigate solvent effects and liquefaction mechanisms. The formation pathways of some special chemicals, including acid intermediates, ketones, and phenols, were proposed based on the structural units of cellulose and lignin.

作为零碳能源，生物质能在实现碳中和目标中发挥重要作用。生物质能的高效转换和利用仍然是一个巨大的挑战。热化学液化是将生物质转化为液体燃料的最有效方法之一。在这项研究中，使用了五种不同的溶剂来液化锯末。结果表明，环己醇的转化率最高，为90.5%，液体收率为79.1%，其次是四氢化萘（81.7%和72.0%），乙醇（70.2%和57.0%），异丙醇（64.5%和47.7%），以及环己烷（57.0% 和 44.5%）。环己醇和四氢呋喃的更好性能是由于它们更大的传质和传热能力，这是由比较溶剂性质决定的。液化气体、液体和固体产物用气相色谱仪进行表征，分别为 GC-MS 和 FT-IR。结果表明，气体中氢气和烃的组成受溶剂供氢体的影响；生物油的分布受氢供体和溶剂副反应的强烈影响；固体残留物主要来自木片成分中的木质素。此外，以微晶纤维素和木质素为模型，进一步研究溶剂效应和液化机理。基于纤维素和木质素的结构单元，提出了酸中间体、酮类、酚类等特殊化学品的形成途径。生物油的分布受氢供体和溶剂副反应的强烈影响；固体残留物主要来自木片成分中的木质素。此外，以微晶纤维素和木质素为模型，进一步研究溶剂效应和液化机理。基于纤维素和木质素的结构单元，提出了酸中间体、酮类、酚类等特殊化学品的形成途径。生物油的分布受氢供体和溶剂副反应的强烈影响；固体残留物主要来自木片成分中的木质素。此外，以微晶纤维素和木质素为模型，进一步研究溶剂效应和液化机理。基于纤维素和木质素的结构单元，提出了酸中间体、酮类、酚类等特殊化学品的形成途径。