title: Natural organic matter removal by adsorption onto magnetic permanently confined micelle arrays.
abstract: To remove natural organic matter (NOM) from water, magnetic permanently confined micelle arrays (Mag-PCMAs) were synthesized by coating the surface of Fe(3)O(4) particles with a silica/surfactant mesostructured hybrid layer. An environmental scanning electron microscope (ESEM) was used to characterize the particle size and surface morphology of the Mag-PCMAs. The zeta potential was used to assess the surface charge. Batch experiments were performed to investigate the adsorption of NOM by Mag-PCMAs. It was determined that NOM removal efficiency by Mag-PCMAs could be as high as 80% at a wide range of initial pH values (∼ 6.0-10.0). The adsorption isotherm was fitted well by a Langmuir model. Although Fe(3)O(4) had a high positive charge and Mag-PCMAs a small negative charge, Mag-PCMAs had a higher removal efficiency of NOM than uncoated Fe(3)O(4) particles (which are also magnetic), which indicated that the adsorption of NOM onto Mag-PCMAs was not dominated by electrostatic interactions. Possible mechanisms of the adsorption of NOM onto Mag-PCMAs were hydrophobic interactions and hydrogen bonding. It was feasible to reuse Mag-PCMAs after regeneration. These results indicate that Mag-PCMAs can be very attractive for the removal of NOM from aqueous matrices.
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. hwang@bren.ucsb.edu
authors.forename: Hongtao
authors.initials: H
authors.lastname: Wang
authors.forename: Arturo A
authors.initials: AA
authors.lastname: Keller
authors.forename: Kristin K
authors.initials: KK
authors.lastname: Clark
mesh_terms: D000327:Adsorption; D007700:Kinetics; D008280:Magnetics; D008823:Micelles; D008855:Microscopy, Electron, Scanning; D009930:Organic Chemicals / Q000302:isolation & purification*; D010316:Particle Size; D013816:Thermodynamics
chemical_list: D008823:Micelles; D009930:Organic Chemicals