IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Applied Surface Analysis Thursday Sessions
       Session AS-ThA

Paper AS-ThA9
The Physical and Chemical Surface Structure of Iron Exposed to Carbon Tetrachloride-Saturated Water

Thursday, November 1, 2001, 4:40 pm, Room 134

Session: Adhesion and Corrosion
Presenter: D.J. Gaspar, Pacific Northwest National Laboratory
Authors: D.J. Gaspar, Pacific Northwest National Laboratory
A.S. Lea, Pacific Northwest National Laboratory
M.H. Engelhard, Pacific Northwest National Laboratory
D.R. Baer, Pacific Northwest National Laboratory
R. Miehr, Oregon Graduate Institute
P.G. Tratnyek, Oregon Graduate Institute
Correspondent: Click to Email
The corrosion of metallic iron by carbon tetrachloride (CCl@sub 4@) has been studied by surface analysis techniques, including time-of-flight secondary ion mass spectrometry (TOF-SIMS), Auger electron spectroscopy (AES), and x-ray photoelectron spectroscopy (XPS). Permeable barriers made of "zero-valent" iron powders are among the methods being considered to assist environmental remediation by catalytic destruction of halogenated solvents. Understanding the chemical and physical properties of the corrosion layer formed on the iron particles is critical in the design of advanced catalysts for environmental remediation because the oxidized layer on the surface of the metallic iron particles is modified during reduction of the halogen-containing species. Among the specific questions is the nature of "active" sites that may facilitate the reduction of the halogenated hydrocarbons. To this end, selected polycrystalline zero-valent iron particles were treated with CCl@sub 4@-saturated water for a period of 1-7 days, and the physical and chemical structure of the surface was studied. The chemical and physical structure of the oxidized iron surface was then examined, revealing localization of chloride within etch pits.