Ultrasound pretreatment of elemental iron: kinetic studies of dehalogenation reaction enhancement and surface effects

    Authors

    C. L. Geiger; N. E. Ruiz; C. A. Clausen; D. R. Reinhart;J. W. Quinn

    Abbreviated Journal Title

    Water Res.

    Keywords

    trichloroethylene; iron; ultrasound; groundwater remediation; ZERO-VALENT IRON; AQUEOUS-SOLUTION; TRICHLOROETHYLENE; DEGRADATION; METALS; Engineering, Environmental; Environmental Sciences; Water Resources

    Abstract

    This work presents data showing the kinetic improvement afforded by ultrasound pretreatment and illustrates the physical and chemical changes that take place at the iron surface. First-order rate constants improved as much as 78% with 2h of ultrasound pretreatment. Scanning electron microscopy (SEM) and surface area analysis were used for confirmation of the physical changes that take place after ultrasound was used on iron surfaces exposed to a variety of conditions. X-ray photoelectron spectroscopy was used to determine chemical surface characteristics before and after ultrasound use. SEM and surface area analysis showed that ultrasound use clears the iron surface of debris increasing the surface area up to 169%. In addition, exposure to ultrasound alters ratios of surface species, such as adventitious carbon to carbonyl carbon and iron to oxygen, and removed hydroxides thus making the iron more reactive to reductive dehalogenation. (C) 2002 Elsevier Science Ltd. All rights reserved.

    Journal Title

    Water Research

    Volume

    36

    Issue/Number

    5

    Publication Date

    1-1-2002

    Document Type

    Article

    Language

    English

    First Page

    1342

    Last Page

    1350

    WOS Identifier

    WOS:000174067800024

    ISSN

    0043-1354

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