The innovative application of organosolv lignin for nanomaterial modification to boost its heavy metal detoxification performance in the aquatic environment

Lignin is one of the most abundant organic materials in the world, and its valuable utilization has become an emerging area of research due to its excellent physical and chemical properties and environmentally friendly characteristics. Nanomaterials hold promise in many fields, however, aggregation and deactivation in the aquatic environment have hindered its development and practical application. Here, the application of organosolv lignin (Org-lignin) for the modification of nanoscale zero-valent iron (nZVI) to boost its hexavalent chromium (Cr(VI)) detoxification performance in the aquatic environment was demonstrated for the first time. Org-lignin was served as stabilizers and Al-bent was selected as carriers to synthesize Org-lignin anchored and aluminum pillared bentonite (Al-bent) supported nZVI (L-nZVI@Ab). Thanks to the dispersing and anchoring effect of Org-lignin, L-nZVI@Ab offered the advantage of aggregation-resistant. Additionally, the synergistic effect of Org-lignin and Al-bent could alleviate the deposition of redox by-products on the surface of nZVI, thereby reducing its deactivation and improving its reusability. These gave L-nZVI@Ab more efficient removal of Cr (VI) than bare nZVI and Al-bent supported nZVI (B-nZVI) in aqueous solution, and the optimal reductive removal amount of Cr(VI) by L-nZVI@Ab was 46.2 mg g(-1). Batch experiments exhibited that the kinetics of Cr(VI) removal by L-nZVI@Ab under various conditions conformed to a pseudo-first-order rate expression. Our work notably expanded possibilities for the use of lignin in the field of nanomaterial modification.