Given the global greenhouse effect caused by excessive CO₂ emissions and fossil energy exploitation, cleaner energy sources are crucial for modern developments. Lignin present in biomass is being considered to replace petroleum due to its abundance and reproducibility. Although the depolymerization of lignin to produce high-value chemicals has gained attention, it encounters significant challenges. Lignin possesses a high molecular weight, and the structural changes during separation often diminish its potential for producing value-added chemicals. This study reviews the recent research on lignin depolymerization using three traditional methods, including hydrolysis, pyrolysis, and hydrogenolysis. First, the lignin hydrolysis is presented, where its properties and mechanisms under various conditions are detailed. Subsequently, the pyrolysis mechanism, products, and pyrolysis methods (catalytic pyrolysis, microwave pyrolysis, molten salt pyrolysis) are discussed in detail. In addition, this study provides a comprehensive summary of hydrogenolysis in terms of both solvent selection and catalytic system. Finally, it addresses challenges and proposes solutions for future lignin value-added research.

中文翻译：

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木质素解聚及高值化利用研究进展


鉴于_{过度的二氧化碳排放}和化石能源开发造成的全球温室效应，更清洁的能源对于现代发展至关重要。由于其丰度和可重复性，存在于生物质中的木质素被认为可以替代石油。尽管木质素的解聚生产高价值化学品已受到关注，但它也遇到了重大挑战。木质素具有高分子量，分离过程中的结构变化通常会降低其生产增值化学品的潜力。本研究回顾了最近使用三种传统方法（包括水解、热解和氢解）进行木质素解聚的研究。首先，介绍了木质素水解，详细介绍了其在各种条件下的性质和机理。随后，详细讨论了热解机理、产物和热解方法（催化热解、微波热解、熔盐热解）。此外，本研究还从溶剂选择和催化系统方面对氢解进行了全面总结。最后，它解决了挑战并为未来的木质素增值研究提出了解决方案。