Advancements and trends in lignin extraction from wood residue: a bibliometric and comprehensive review

This review examines the progress in lignin extraction, emphasizing the shift towards sustainable and efficient methods. It evaluates current extraction techniques, particularly the use of green technologies like organosolv processes, ionic liquids, and deep eutectic solvents. A bibliometric analysis of research trends over the last decade shows a rise in studies focused on green extraction methods. The review compares traditional and emerging methods, highlighting their efficiencies, yields, and environmental impacts. Although traditional methods remain prevalent, there is a growing adoption of greener alternatives driven by sustainability concerns. The review also explores lignin’s potential as a valuable feedstock for producing high-value products in energy, materials, chemicals, and pharmaceuticals. The review concludes that while traditional lignin extraction methods still dominate, green alternatives are steadily gaining traction due to their environmental and economic benefits. The adoption of these methods is crucial for enhancing lignin's commercial value and sustainability in various industries, especially the biorefinery sector. Future research should focus on optimizing these green technologies and addressing existing challenges to improve the overall efficiency and scalability of lignin extraction processes.