Several lignin samples of varying botanical nature (softwood, hardwood, or annual plants) and extraction procedures (Kraft, Organosolv, or soda) were fully characterized by complementary techniques and engaged in “catalyst-free” depolymerization in air under basic conditions. Treatment of the complex reaction mixture was optimized to ensure reproducibility, careful analyses, and accurate data. After an optimization of the reaction conditions, we were able to recover high amounts of aromatic compounds (up to 19%_wt). Additionally, we demonstrated a relation between lignin’s structure, i.e., the accessible phenol moieties and inter-unit linkages, and the yields of aromatic compounds, thus showing the importance of the extraction process to optimize lignin’s potential. This work provides valuable reference for developing further lignin depolymerization under basic media.

Graphical abstract

几种具有不同植物性质的木质素样品（软木，硬木或一年生植物）和提取程序（Kraft，Organosolv或苏打水）已通过互补技术充分表征，并在基本条件下在空气中进行了“无催化剂”解聚。对复杂反应混合物的处理进行了优化，以确保可重复性，仔细的分析和准确的数据。在优化反应条件之后，我们能够回收大量的芳族化合物（高达19％_wt）。此外，我们证明了木质素的结构（即可接近的酚部分和单元间键合）与芳香族化合物的收率之间的关系，从而表明了提取工艺对优化木质素潜力的重要性。这项工作为在碱性介质下进一步开发木质素解聚提供了有价值的参考。

图形概要