Modulation of Electron-Rich Heteroatom Cross-Linked Lignin Molecular Cages and Their Potential Application in...

Lignin, a natural biomass material, has demonstrated potential for iodine capture. However, in practical implementation, its effectiveness is limited. To address these issues, we screened four electron-rich heteroatom diamine compounds for cross-linking modification of lignin. By precisely controlling reaction parameters, we successfully synthesized four electron-rich heteroatom-cross-linked lignin molecular cages. These molecular cages feature a unique structure: un-cross-linked lignin nanospheres are attached on the inner surface of the cage. EC-L(N) demonstrates exceptional iodine capture performance: its iodine vapor capture capacity reaches 304.95 mg/g, with capture capacities of 595.68 mg/g in n-hexane solution and 264.32 mg/g in aqueous solution. Further, EC-L(N) demonstrated exceptional reusability. This study not only provides key technical support for optimizing the adsorption performance of lignin-based iodine capture materials and expanding their practical applications in radioactive wastewater and exhaust gas treatment, but also offers important theoretical insights for the structural design and functional development of electron-rich heteroatom-modified biomass materials.