Cellulose-Supported Nanosized Zinc Oxide: Highly Efficient Bionanomaterial for Removal of Arsenic from Water

Arsenic contamination in drinking water has become a worldwide problem, especially in developing countries, and has led to the development of various arsenic removal methods. Herein, regenerated microfibrillated cellulose (R-MFC) fibers were isolated by a combination of dissolution and regeneration methodologies using a mixture of phosphoric acid and ethanol treatment on jute cellulose. The isolated R-MFC fibers possessed high specific surface area (10 m/g), good aspect ratio (L/D = 30), high thermal stability (T = 352 °C) with a zeta potential of -8.4 mV, and a low crystallinity index of 47.5%. These R-MFC fibers exist in cellulose II polymorph form, confirmed by C CPMAS nuclear magnetic resonance and wide-angle X-ray diffraction studies, and they were highly effective as support for growth of ZnO nanocrystals. Wide-angle X-ray diffraction and transmission electron microscopy analysis on the imbedded ZnO nanocrystals indicated that they possessed the hexagonal wurtzite crystal structure. The R-MFC composite loaded with 41 wt% of ZnO nanocrystals was found to be highly efficient in removing arsenic ions from contaminated water, with a maximum capacity of 4,421 mg/g at neutral pH, which is significantly higher than the various absorbents for arsenic removal reported in the literature