title: Rapid removal of organic micropollutants from water by a porous β-cyclodextrin polymer.
abstract: The global occurrence in water resources of organic micropollutants, such as pesticides and pharmaceuticals, has raised concerns about potential negative effects on aquatic ecosystems and human health. Activated carbons are the most widespread adsorbent materials used to remove organic pollutants from water but they have several deficiencies, including slow pollutant uptake (of the order of hours) and poor removal of many relatively hydrophilic micropollutants. Furthermore, regenerating spent activated carbon is energy intensive (requiring heating to 500-900 degrees Celsius) and does not fully restore performance. Insoluble polymers of β-cyclodextrin, an inexpensive, sustainably produced macrocycle of glucose, are likewise of interest for removing micropollutants from water by means of adsorption. β-cyclodextrin is known to encapsulate pollutants to form well-defined host-guest complexes, but until now cross-linked β-cyclodextrin polymers have had low surface areas and poor removal performance compared to conventional activated carbons. Here we crosslink β-cyclodextrin with rigid aromatic groups, providing a high-surface-area, mesoporous polymer of β-cyclodextrin. It rapidly sequesters a variety of organic micropollutants with adsorption rate constants 15 to 200 times greater than those of activated carbons and non-porous β-cyclodextrin adsorbent materials. In addition, the polymer can be regenerated several times using a mild washing procedure with no loss in performance. Finally, the polymer outperformed a leading activated carbon for the rapid removal of a complex mixture of organic micropollutants at environmentally relevant concentrations. These findings demonstrate the promise of porous cyclodextrin-based polymers for rapid, flow-through water treatment.
authors.affiliation: Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York 14853, USA.
authors.forename: Alaaeddin
authors.initials: A
authors.lastname: Alsbaiee
authors.affiliation: Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York 14853, USA.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Smith
authors.affiliation: Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York 14853, USA.
authors.forename: Leilei
authors.initials: L
authors.lastname: Xiao
authors.affiliation: School of Civil and Environmental Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Yuhan
authors.initials: Y
authors.lastname: Ling
authors.affiliation: School of Civil and Environmental Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Damian E
authors.initials: DE
authors.lastname: Helbling
authors.affiliation: Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York 14853, USA.
authors.forename: William R
authors.initials: WR
authors.lastname: Dichtel
mesh_terms: D000327:Adsorption; D001559:Benzhydryl Compounds / Q000737:chemistry / Q000302:isolation & purification; D002482:Cellulose / Q000138:chemical synthesis / Q000737:chemistry*; D002606:Charcoal / Q000737:chemistry; D003505:Cyclodextrins / Q000138:chemical synthesis / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification; D016062:Porosity; D059027:Recycling / Q000191:economics / Q000379:methods; D013696:Temperature; D013997:Time Factors; D014865:Waste Disposal, Fluid / Q000191:economics / Q000379:methods; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000191:economics / Q000379:methods*; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D002482:Cellulose; D002606:Charcoal; D003505:Cyclodextrins; D010636:Phenols; D014867:Water; D014874:Water Pollutants, Chemical; C041953:cyclodextrin polymer; C006780:bisphenol A; D000098826:Bisphenol A Compounds