LanguageTerm (authority = ISO 639-3:2007); (type = text)
English
Abstract (type = abstract)
Understanding the redox transformations of inorganic forms of mercury (Hg) is necessary for understanding the fate of mercury in environmental systems. In this study, the interactions of Hg(0) and Hg(II) with organic and inorganic substances were characterized using mercury stable isotopes. Interactions of a mixed Hg(0)-Hg(II) solution with thiol and humic substances were observed, with no net changes to redox speciation. In the presence of mercaptoacetic acid (MCA), an equilibrium isotope enrichment factor (ε202Hg = δ202HgHg(II) - δ202HgHg(0)) of 1.34‰ between the Hg(II) and Hg(0) fractions was observed, similar with previously published values for Hg(0) oxidation by thiols. The equilibrium ε202Hg values similarly determined for 2-mercaptopropionic acid (MPA) and Suwannee River humic acids were 2.03‰ and 1.50‰, respectively. Reduction of mercury by siderite (FeCO3) was also characterized with respect to isotope fractionation over the course of the reaction. This reaction resulted in an 87% reduction of Hg(II) over 30 minutes, with change in mercury isotope ratios of the reactant. Kinetic ε202Hg values for the reduction of Hg(II) by siderite (ε202Hg = δ202HgHg(0) - δ202HgHg(II)) were determined by closed-system model (-1.59‰) and Rayleigh distillation model (-1.07‰; product enrichment in light isotopes). The final equilibrium state exhibited an equilibrium ε202Hg of -0.67‰. The results from the experiments conducted suggest that there is equilibrium isotope exchange between thiol-bound Hg(II) and dissolved Hg(0), and that the reduction by siderite is rapid and may involve multiple processes through the reaction.
Subject (authority = RUETD)
Topic
Environmental Sciences
Subject (authority = local)
Topic
Mercury redox
Subject (authority = LCSH)
Topic
Mercury
RelatedItem (type = host)
TitleInfo
Title
Rutgers University Electronic Theses and Dissertations
I hereby grant to the Rutgers University Libraries and to my school the non-exclusive right to archive, reproduce and distribute my thesis or dissertation, in whole or in part, and/or my abstract, in whole or in part, in and from an electronic format, subject to the release date subsequently stipulated in this submittal form and approved by my school. I represent and stipulate that the thesis or dissertation and its abstract are my original work, that they do not infringe or violate any rights of others, and that I make these grants as the sole owner of the rights to my thesis or dissertation and its abstract. I represent that I have obtained written permissions, when necessary, from the owner(s) of each third party copyrighted matter to be included in my thesis or dissertation and will supply copies of such upon request by my school. I acknowledge that RU ETD and my school will not distribute my thesis or dissertation or its abstract if, in their reasonable judgment, they believe all such rights have not been secured. I acknowledge that I retain ownership rights to the copyright of my work. I also retain the right to use all or part of this thesis or dissertation in future works, such as articles or books.