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RECOVERY OF MERCURY FROM CONTAMINATED PRIMARY AND SECONDARY WASTES

Description: Effective removal of mercury contamination from water is a complex and difficult problem. In particular, mercury treatment of natural waters is difficult because of the low regulatory standards. For example, the Environmental Protection Agency has established a national ambient water quality standard of 12 parts-per-trillion (ppt), whereas the standard is 1.8 ppt in the Great Lakes Region. In addition, mercury is typically present in several different forms, but sorption processes are rarely effective with more than one or two of these forms. To meet the low regulatory discharge limits, a sorption process must be able to address all forms of mercury present in the water. One approach is to apply different sorbents in series depending on the mercury speciation and the regulatory discharge limits. Four new sorbents have been developed to address the variety of mercury species present in industrial discharges and natural waters. Three of these sorbents have been field tested on contaminated creek water at the Y-12 Plant. Two of these sorbents have demonstrated very high removal efficiencies for soluble mercury species, with mercury concentrations at the outlet of a pilot-scale system less than 12 ppt for as long as six months. The other sorbent tested at the Y-12 Plant is targeted at colloidal mercury that is not removed by standard sorption or filtration processes. At the Y-12 Plant, colloidal mercury appears to be associated with iron, so a sorbent that removes mercury-iron complexes in the presence of a magnetic field was evaluated. Field results indicate good removal of this mercury fraction from the Y-12 waters. In addition, this sorbent is easily regenerated by simply removing the magnetic field and flushing the columns with water. The fourth sorbent is still undergoing laboratory development, but results to date indicate exceptionally high mercury sorption capacity. The sorbent is capable of ...
Date: January 13, 2000
Creator: Faucette, A.; Bognar, J.; Broderick, T. & Battaglia, T.
Partner: UNT Libraries Government Documents Department

[News Clip: North Park]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: October 13, 1979, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Radiation Laboratory, University of Notre Dame. Quarterly report, July 1, 1977--September 30, 1977. [Short summaries of progress in 27 projects]

Description: Status of the following investigations is given: effect of molecular geometry on the electron affinity of H/sub 2/O; effect of non-spherically symmetric exchange potential in energy transfer and CIDEP; fragmentation patterns in the radiolysis of normal alkanes; properties of solvated electrons; temperature dependence of electron localization and impurity trapping in methanol and propanol; field-dependent electron mobility; aluminium cluster and organoaluminum systems; collision-induced atomic dipole moments; T-R energy transfer between electronically excited atoms and ground state molecules; correlation between the anisotropy of polarizability and electron-density contour diagrams; high-field conduction in thin-film alkali halides; chemically induced electron polarization of t-butyl radicals in solution; nonlinear response of radical systems to modulated initiation; measurement of electron spin-lattice relaxation times; electron attachment to N/sub 2/O in the gas phase; laser fluorescence of cyclohexadienyl radical in irradiated benzene crystals; kinetics of radical exchange between micelles and water; dynamics of probe molecules in a micellar environment; radiolytic reduction of colloidal silver bromide; characterization of structure in fatty acid aggregate systems; photochemical reactions of Cu(II) complexes with macrocyclic ligands; studies of Ni(III) macrocyclic complexes; rateconstant for oxidation of hydroxycyclohexadienyl radical by ferricyanide; alkoxyl radical reactions with lipids; luminescence from diarylcarbenes; excited-state reactions of 7-hydroxy-4-methyl coumarin; photochronic aziridines; and photochemistry of acetylacetonate complexes of d/sup 6/ metal ions. (LK)
Date: October 13, 1977
Partner: UNT Libraries Government Documents Department

Radiation Laboratory, University of Notre Dame. Quarterly report, April 1, 1977--June 30, 1977. [One paragraph summaries of various investigations]

Description: Investigations in progress include: ionization potentials of H/sub 2/O from molecular orbital and valence bond wavefunctions; early events in pulse-irradiated polar liquids; epithermal trapping of electrons; range of photoionized electrons in high-mobility liquids using field-dependent mobility; scattering of exciton by the impurity; model molecular orbital studies of the chemisorption of atomic hydrogen and oxygen on aluminium surfaces; laser induced fluorescence and the geometry of the excited states of tetra-methyl cyclobutanedione; fluorescence studies of hydrogen adduct and raman studies of radical anion; energy transfer studies between electronically excited atoms and ground state molecules; kinetics and chemically induced electron polarization (CIDP) of transient radicals in solution by modulation ESR spectroscopy, CIDP of t-butyl radicals in solutions; ESR spectra of phosphate, sulfate, and hydroxyl radical adducts to unsaturated carboxylic acids; high-field conduction in thin-film alkali halides; electron reactions in the gas phase; interaction of triplet biradicals with ground state molecular oxygen; reactions of Cl/sub 2//sup -/ radicals with organic compounds; oxidation of Ni(II) macrocyclic complexes by OH radicals; photochemical reactions of Cu(II) complexes with macrocyclic ligands; fast reaction kinetics in fatty acid soap aggregates; the dynamics of probe molecules in a micelle environment; the effect of a micellar phase on the state and dynamics of some excited state charge transfer complexes; and conformation studies of fluorescent copolymers in aqueous solutions. Abstracts of reports published this quarter are provided. (LK)
Date: July 13, 1977
Partner: UNT Libraries Government Documents Department

[News Clip: 2-alarm fire]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: August 13, 1984, 12:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

FORMATION CONSTANTS OF THE COMPLEX SPECIES FORMED BY INTERACTION OF RARE- EARTH NITRILOTRIACETATE COMPLEXES WITH AN EQUIVALENT AMOUNT OF BASE

Description: The formation constants of the RChOH/sup -/ species, formed by interaction of individual rare-earth nitrilotriacetate species and KOH at 25 deg C and an ionic strength of 0.1 were determined by the potentiometric method, i.e., computed from the pH values of equilibrium mixtures containing varying proportions of rare-earth complex and base. The relations of these constants to the ion-exchange separation of rare earths at high pH were discussed. (auth)
Date: April 13, 1962
Creator: Gupta, A.K. & Powell, J.E.
Partner: UNT Libraries Government Documents Department