Hydrogen‐transfer strategy in lignin refinery: Towards sustainable and versatile value‐added biochemicals

Lignin, the most prevalent natural source of polyphenols on Earth, offers substantial possibilities for the conversion into aromatic compounds, which is critical for attaining sustainability and carbon neutrality. The hydrogen‐transfer method has garnered significant interest owing to its environmental compatibility and economic viability. The efficacy of this approach is contingent upon the careful selection of catalytic and hydrogen‐donating systems that decisively affect the yield and selectivity of the monomeric products resulting from lignin degradation. This paper highlights the hydrogen‐transfer technique in lignin refinery, with a specific focus on the influence of hydrogen donors on the depolymerization pathways of lignin. It delineates the correlation between the structure and activity of catalytic hydrogen‐transfer arrangements and the gamut of lignin‐derived biochemicals, utilizing data from lignin model compounds, separated lignin, and lignocellulosic biomass. Additionally, the paper delves into the advantages and future directions of employing the hydrogen‐transfer approach for lignin conversion. In essence, this concept investigation illuminates the efficacy of the hydrogen‐transfer paradigm in lignin valorization, offering key insights and strategic directives to maximize lignin's value sustainably. The hydrogen‐transfer strategy is pivotal in realizing sustainable and eco‐friendly lignin refinement. This concept review concentrates on the attributes of multifunctional hydrogen donors and their utilization in the upgrading of lignin‐derived materials. The paper explores both the present challenges and the prospective avenues for advancing the hydrogen‐transfer strategy within the realm of lignin refinement.