Publication Date

2020

Document Type

Thesis

Committee Members

Abinash Agrawal, Ph.D. (Advisor); Chad Hammerschmidt, Ph.D. (Committee Member); Silvia Newell, Ph.D. (Committee Member); Hailiang Dong, Ph.D. (Committee Member)

Degree Name

Master of Science (MS)

Abstract

Fe(II)-containing minerals (often as oxides and sulfides) are commonly present in the shallow subsurface and aquifers. Recent studies have shown that Fe(II) can generate reactive oxygen species upon oxygenation. This bench-scale investigation examined the generation of radical species from [Fe(II)]-containing mineral phases when exposed to oxygen. The Fe(II)-minerals in this study were chemically-reduced hydrous ferric oxide (HFO) and goethite, magnetite, and mackinawite (FeS). This research demonstrated that trichloroethene (TCE) can rapidly degrade by radicals produced from Fe(II)-containing oxides if gaseous oxygen is introduced in reactors. In contrast, there was little or no TCE degradation from oxygenation of freshly-prepared ferrous sulfide (FeS). This suggests radicals were not produced by oxygenation due to the lack of TCE degradation. The result of this study indicated an increase of TCE degradation kinetics with increasing Fe(II) concentrations in chemically-reduced HFO, goethite and magnetite, and has important implications in natural attenuation of TCE at contaminated sites.

Page Count

79

Year Degree Awarded

2020


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