Title

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

Authors

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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