Role of superoxide anion in contaminant degradation by hydrogen peroxide in the presence of sandy aquifer material

Journal Article · Tue Dec 31 04:00:00 EST 1996 · National Meeting - American Chemical Society, Division of Environmental Chemistry

OSTI ID:437326

Miller, C M ^[1]; Valentine, R L ^[2]

---

1. Univ. of Akron, OH (United States)
2. Univ. of Iowa, Iowa City, IA (United States)

The decomposition of hydrogen peroxide (H{sub 2}O{sub 2}) in the presence of metal oxides has frequently been described by a modified Haber-Weiss mechanism, which involves a redox reaction where H{sub 2}O, can accept an electron from a metal surface site (Eq. 1) or donate an electron to a surface site (Eq.2), S + H{sub 2}O{sub 2} {r_arrow}S{sup +} + OH{sup -} + {lg_bullet}OH S{sup +} + H{sub 2}O{sub 2} {r_arrow} S + H{sup +} + {lg_bullet}HO{sub 2} where [S] represents a reduced surface site and [S+] represents an oxidized surface site respectively. These reactions involve the formation of hydroxyl radical (OH{lg_bullet}) and perhydroxyl radical ({lg_bullet}HO{sub 2}). in addition, superoxide anion (O{sub 2}{sup -}) is present because it is in equilibrium with {lg_bullet}HO according to: {lg_bullet}HO{sub 2}{longleftrightarrow} H{sup +} + O{sub 2}- pKa=4.8. The hydroxyl radical is a non-specific powerful oxidant, capable of reacting with a number of organic compounds at near diffusion-limited reaction rates. Consequently, several researchers have studied surface catalyzed H{sub 2}O{sub 2} decomposition for the purpose of organic contaminant degradation. For example, trichloroethylene and pentachlorophenol were effectively degraded in column experiments with H{sub 2}O{sub 2} and a coarse sand. The purpose of this study was to examine the role of superoxide anion in the degradation of contaminants in materials similar to aquifer materials.

• OSTI ID: 437326
• Report Number(s): CONF-960807--
• Journal Information: National Meeting - American Chemical Society, Division of Environmental Chemistry, Journal Name: National Meeting - American Chemical Society, Division of Environmental Chemistry Journal Issue: 2 Vol. 36; ISSN NMACDY; ISSN 0270-3009
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AQUIFERS
DECOMPOSITION
HYDROGEN PEROXIDE
HYDROXYL RADICALS
NITROBENZENE
PHENOL
QUINOLINES
REMEDIAL ACTION
SAND
SUPEROXIDE RADICALS