Development of Nanoporous Cellulose Nanocrystals by Molecular Cross‐Linking for Efficient Adsorption of Cr(<scp>VI</scp>) and Mn(<scp>VII</scp>)

ABSTRACT Continued industrial activities have discharged massive amounts of pollutants into water systems, posing serious risks to human health. To address these environmental challenges, it is essential to develop a green, high‐performance adsorbent for effective water purification. In this study, efficient, mesoporous, amino‐functionalized polydivinylbenzene (PDVB)‐cellulose nanocrystals (CNC/PDVB‐NH 2 ) with high stability and superhydrophobicity were synthesized by crosslinking. The prepared CNC/PDVB‐NH 2 nanomaterial has been characterized using x‐ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and x‐ray photoelectron spectroscopy (XPS), and so forth. The adsorption of Cr(II) and Mn(III) ions on CNC/PDVB‐NH 2 follows the pseudo‐second‐order and Langmuir models, indicating a monolayer chemisorption mechanism. The maximum adsorption capacities ( q m ) of CNC/PDVB‐NH 2 for Cr(VI) and Mn(VII) ions are 130.39 and 308.94 mg/g, respectively. These results demonstrate that CNC/PDVB‐NH 2 is an efficient and reliable absorbent for wastewater treatment and holds great potential for large‐scale application.