Depolymerization of lignin into aromatic monomers is one of the highest priority targets for valorization of lignin obtained from biomass pretreatment. Oxidative lignin depolymerization proceeds rapidly under alkaline conditions at elevated temperature with O₂; however, the aromatic products are susceptible to degradation under the same conditions, complicating practical application of these conditions. Here, we report a continuous-flow aerobic alkaline lignin depolymerization method using an O₂-permeable membrane reactor. The flow reactor allows for continuous oxygen delivery to the alkaline lignin solution and precise control of the temperature and reaction time. Reaction time-course analysis provides direct insights into the rates of lignin depolymerization and monomer decomposition, enabling process optimization. Aromatic yields up to 43 wt % are observed with a residence time of less than 4 min. This process is applied to the depolymerization of multiple lignin materials derived from different biomass pretreatment methods and from both softwood and hardwood sources.

将木质素解聚为芳香族单体是生物质预处理获得的木质素增值的最优先目标之一。氧化木质素解聚在碱性条件下在升高的温度下用O ₂快速进行；然而，芳香族产物在相同条件下容易降解，使这些条件的实际应用变得复杂。在这里，我们报道了一种使用O ₂渗透膜反应器的连续流好氧碱性木质素解聚方法。流动反应器允许将氧气连续输送至碱性木质素溶液并精确控制温度和反应时间。反应时程分析可直接了解木质素解聚和单体分解的速率，从而实现工艺优化。停留时间小于 4 分钟时，芳烃收率高达 43 wt%。该工艺适用于来自不同生物质预处理方法以及来自软木和硬木来源的多种木质素材料的解聚。