Recent Advances in Lignin Modification and Its Application in Wastewater Treatment

In recent years, lignin and its derivatives as wastewater treatment agents have received extensive attention due to their many advantages, including their renewable raw materials, superior performance, biodegradability, and no secondary pollution. The chapter systematically reviews the recent progress of lignin and its derivatives as adsorbents, flocculants and sterilants, and other wastewater treatment agents. It is emphatically introduced that chemical modifications can effectively control and adjust the structure of lignin to improve its wastewater treatment capacity. Moreover, the purification mechanisms and their influencing factors are discussed in detail. In addition, the chapter also critically points out the deficiencies of lignin-based wastewater treatment agents at the present stage and proposes corresponding improvement approaches. Furthermore, the future research emphasis and development direction of lignin and its derivatives in wastewater treatment are discussed.