Facile fabrication of carboxylated cellulose nanocrystal-MnO(2)beads for high-efficiency removal of methylene blue

As a sustainable nanomaterial, cellulose nanocrystal (CNC) based adsorbents exhibited great potential in wastewater treatment due to their high specific surface area, easy surface functionalization and excellent mechanical strength. Herein, a facile, green and energy-efficient method was proposed to fabricate the CNC/manganese dioxide (MnO2)/alginate (ALG) beads. The hybrid CNC/MnO(2)nanocomposites were prepared by a simple and fine purification "one-pot" synthesis process and then anchored onto ALG networks directly to form the triphase beads in a continuous and automated mode. Interestingly, the CNC/MnO2/ALG beads exhibited excellent adsorption and oxidative degradation of methylene blue after a regeneration process. The decolorizing efficiency and capacity could reach up to 99.8% and 136.7 mg/g, respectively. Meanwhile, the CNC/MnO2/ALG beads can maintain their high efficiency (~ 95% of initial value) even after 10 cycles, indicating excellent recyclability and durability. It provides us a new route to design novel hybrid materials for environmental remediation. Graphic abstract