title: Reactive nanostructured membranes for water purification.
abstract: Many current treatments for the reclamation of contaminated water sources are chemical-intensive, energy-intensive, and/or require posttreatment due to unwanted by-product formation. We demonstrate that through the integration of nanostructured materials, enzymatic catalysis, and iron-catalyzed free radical reactions within pore-functionalized synthetic membrane platforms, we are able to conduct environmentally important oxidative reactions for toxic organic degradation and detoxification from water without the addition of expensive or harmful chemicals. In contrast to conventional, passive membrane technologies, our approach utilizes two independently controlled, nanostructured membranes in a stacked configuration for the generation of the necessary oxidants. These include biocatalytic and organic/inorganic (polymer/iron) nanocomposite membranes. The bioactive (top) membrane contains an electrostatically immobilized enzyme for the catalytic production of one of the main reactants, hydrogen peroxide (H(2)O(2)), from glucose. The bottom membrane contains either immobilized iron ions or ferrihydrite/iron oxide nanoparticles for the decomposition of hydrogen peroxide to form powerful free radical oxidants. By permeating (at low pressure) a solution containing a model organic contaminant, such as trichlorophenol, with glucose in oxygen-saturated water through the membrane stack, significant contaminant degradation was realized. To illustrate the effectiveness of this membrane platform in real-world applications, membrane-immobilized ferrihydrite/iron oxide nanoparticles were reacted with hydrogen peroxide to form free radicals for the degradation of a chlorinated organic contaminant in actual groundwater. Although we establish the development of these nanostructured materials for environmental applications, the practical and methodological advances demonstrated here permit the extension of their use to applications including disinfection and/or virus inactivation.
authors: Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506-0046, USA.
authors: Scott R
authors: SR
authors: Lewis
authors: Saurav
authors: S
authors: Datta
authors: Minghui
authors: M
authors: Gui
authors: Eric L
authors: EL
authors: Coker
authors: Frank E
authors: FE
authors: Huggins
authors: Sylvia
authors: S
authors: Daunert
authors: Leonidas
authors: L
authors: Bachas
authors: Dibakar
authors: D
authors: Bhattacharyya
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