Shenyang Aerospace University, College of Energy and Environment, Key Laboratory of Clean Energy of Liaoning

木质素是具有芳香族结构的天然可再生资源，可以通过水热液化技术将其转化为生物油。不同种类的木质素结构特点和反应活性存在差异，故本研究选取三种木质素（工业碱木质素（KL）、酶解木质素（EHL）和乙醇木质素（OL））为原料，首先对三种原料理化特性进行分析；其次考察反应条件对三种木质素水热液化生物油特性的影响。在三种木质素中，EHL、OL为愈创木基型结构。OL的C、H元素含量最高，其高位热值为23.54 MJ/kg，芳香特征更加明显，酚羟基含量相对较高。KL为紫丁香基型结构，甲氧基与酚羟基含量较少。液化实验结果显示，反应温度为300 ℃时，木质素生物油产率及能量回收率最高，该温度下产率OL>KL>EHL，生物油的H/C比值为1.0–1.4。三种生物油化学成分不同，OL生物油中含有9.14%的芳香烃，EHL生物油酚类物质含量达到41.34%，KL生物油中酸类含量较高。

Lignin is a natural and renewable resource with aromatic structure. It can be converted into bio-oil by hydrothermal liquefaction. Due to the complex structure of wood fiber, the structural characteristics and reactivity of different kinds of lignin are different. Therefore, three typical lignin (kraft lignin (KL), enzymatic hydrolysis lignin (EHL) and ethanol lignin (OL)) were selected as raw materials. Firstly, physical and chemical properties of the raw materials were analyzed. Secondly, effects of reaction conditions on characteristics of their hydrothermal liquefaction bio-oil were investigated. Among them, EHL and OL are guaiacyl units. OL has the highest content of carbon and hydrogen elements, and its higher heating value reaches 23.54 MJ/kg. The aromatic characteristics are more obvious, and the phenolic hydroxyl content is relatively high. KL is mainly syringyl unit with less methoxy and phenolic hydroxyl groups. The results of liquefaction experiment show that when the reaction temperature was 300 ℃, yield and energy recovery rate of lignin bio-oil were the highest. The bio-oil yield ranked in the order of OL>KL>EHL. H/C ratio of bio-oil was concentrated within 1.0-1.4. Chemical composition of the three bio-oils was different. OL bio-oil contains 9.14% aromatic hydrocarbons, EHL bio-oil contains 41.34% phenolic species, and KL bio-oil has a higher acid content.

国家自然科学基金（52176195）和辽宁省兴辽英才计划（XLYC200512）资助

杨天华, 刘正, 李秉硕, 张海军, 王鹤逸. 三种木质素水热液化制备生物油实验研究[J]. 燃料化学学报（中英文）, 2023, 51(8): 1084-1095.

YANG Tian-hua, LIU Zheng, LI Bing-shuo, ZHANG Hai-jun, WANG He-yi. Experimental study on preparation of bio-oil by hydrothermal liquefaction of three kinds of lignin[J]. Journal of Fuel Chemistry and Technology, 2023, 51(8): 1084-1095.