Method for preparing aromatic monomer from lignin

Abstract

The invention provides a lignin aromatic monomer preparation method which comprises the following steps: predicting cracking yields under different pretreatment conditions according to a pretreatment optimization model, and determining a pretreatment condition with the highest cracking yield from the different pretreatment conditions as a target pretreatment condition; the target pretreatment conditions comprise the concentration of the acidic catalyst in the pretreatment liquid, the pretreatment temperature and the pretreatment reaction time; crushing and pre-extracting the biomass raw material; preparing a pretreatment solution according to a target pretreatment condition, mixing the crushed and pre-extracted product with the pretreatment solution, adding the mixture into a pretreatment reactor, performing pretreatment according to the target pretreatment condition, and collecting the product to obtain an acidic lignin-rich solution; neutralizing the acidic lignin-rich solution to obtain a neutral lignin-rich solution; and cracking the lignin-rich solution to obtain the lignin aromatic monomer. According to the method, the biomass raw material is treated under the optimal pretreatment condition, and the integrity of lignin and the yield of aromatic monomers are both considered. 本申请提供了一种木质素芳香类单体制备方法，包括：根据预处理优化模型预测不同预处理条件下的裂解产率，并从不同预处理条件中确定裂解产率最高的预处理条件为目标预处理条件；目标预处理条件包括预处理液中酸性催化剂的浓度、预处理温度、预处理反应时间；对生物质原料进行破碎和预萃取；根据目标预处理条件配置预处理液，将破碎和预萃取的产物与预处理液混合后加入预处理反应器，并根据目标预处理条件进行预处理并收集产物，得到酸性富木质素溶液；对酸性富木质素溶液进行中和，得到中性的富木质素溶液；将富木质素溶液进行裂解得到木质素芳香类单体。该方法以最优的预处理条件对生物质原料进行处理，兼顾了木质素完整性和芳香类单体产率。