β‑Cyclodextrin Polymerized in Cross-Flowing Channels of Biomass Sawdust for Rapid and Highly Efficient Pharmaceutical Pollutants Removal from Water

Water pollution aroused from pharmaceuticals has raised great concerns about the potential risks for biosphere and human health. However, rapid and efficient removal of pharmaceutical contaminants from water remains challenging. Wood sawdust, a by-product of the wood processing industry, is an abundant, cost effective, and sustainable material with a unique hierarchically porous microstructure. These features make wood sawdust quite interesting as a filtration material. Here, the author reports a novel cross-flow filtration composite based on β cyclodextrin polymer functionalized wood sawdust (denoted as β-CD/WS), in which the pharmaceutical contaminant water flows through the sawn-off vessel channels and the micropores on the surface of the cell walls, generating the turbulence. Such water flow characteristics ensure full contact between pharmaceutical pollutants and β-CD grafted on the cellulose backbone of wood sawdust, thereby enhancing the water treatment efficiency. Consequently, the β-CD/WS filter device shows a high removal efficiency of over 97.5% within 90 seconds for various pharmaceutical contaminants including propranolol, amitriptyline, chlortetracycline, diclofenac and levofloxacin, and a high saturation uptake capacity of 170, 156, 257, 159, and 185 mg g-1, respectively. The high-performance wood-sawdust-based cross-flow filtration opens new avenues for solving the global water pollution issues, especially those caused by pharmaceutical contaminants.