Inorganic Chemistry Commons^™

Ligands For Complexation, Extraction, And Sensing Of Mercury(Ii) For Application To High-Level Waste (Hlw) At The Savannah River Site (Srs), Adenike O. Fasiku

FIU Electronic Theses and Dissertations

Mercury (Hg) separation and sensing is of high significance due to Hg^(II) environmental mobility and toxicity. Furthermore, the use of Hg in nuclear applications has resulted in its accumulation in several DOE sites, such as in Oak Ridge and Savannah River reservations. Organic mercury species have been found in low activity waste (LAW) streams resulting from high-level waste (HLW) processing at the Savannah River Site (SRS), therefore posing a threat to humans and the environment. Mercury, being a soft Lewis acid, has a strong affinity for softer Lewis bases, such as S- or N-donor ligands. Therefore, we focus on …

The Coordination Chemistry Of The Rhodizonate Dianion And Its Decomposition Products, Joshua A. Silverman

FIU Electronic Theses and Dissertations

The rhodizonate dianion is of importance for forensic testing, specifically with regard to the sodium rhodizonate test for lead in gunpowder residues. In an effort to understand this test from a chemical perspective, the coordination of rhodizonate and its decomposition products, croconate and oxalate, with several metals has been investigated with a variety of structural and spectroscopic methods.

FT-IR data of the three sequential steps of the sodium rhodizonate test show coordination between Pb(II) atoms, tartrate anions, and rhodizonate dianions, with the tartrate being substituted for Cl^- once a 5% HCl solution is added to produce the confirmatory blue-purple …

Competitive Reductive Removal Of Chromate And Pertechnetate Via Zero-Valent Iron, Jonathan Williams Ramirez

FIU Electronic Theses and Dissertations

Treatment to immobilize radioactive waste is of concern for long-term storage, avoiding future environmental exposure. Most production of Technetium-99 (⁹⁹Tc) occurred as a byproduct of development of legacy nuclear weapons research. Zero-valent iron (ZVI) is a promising reductant of Tc(VII) to a less mobile ⁹⁹Tc(IV). However, more redox-sensitive contaminants can compete in the reductive process. Therefore, it is important to examine the effects of competitive contaminants and quantify the effects on the reductive removal rates of ⁹⁹Tc. Chromate, Cr(VI), is a redox-sensitive contaminant that is expected to be present in legacy waste present in the Hanford …

Uranium Fate And Mineral Transformations Upon Remediation With Ammonia (Nh3) Gas, Silvina A. Di Pietro

FIU Electronic Theses and Dissertations

The fission of uranium (U) for plutonium production was a major activity at the U.S. Department of Energy’s (DOE) Hanford Site in Washington State during World War II and Cold War. This endeavor resulted in the generation of over two million liters of high-level radioactive waste, most of which still remains in 177 underground storage tanks. Due to the improper storage and aging of these tanks in addition to other waste releases across the Site, approximately 200,000 kg of U have been released into the vadose zone. The objective of this study was to determine whether the application of the …