Neptunium adsorption on synthetic amorphous iron oxyhydroxide

Girvin, D.C.; Ames, L.L.; Schwab, Allen P; McGarrah, J.E.

doi:10.1016/0021-9797(91)90303-p

Cited by 76 publications

(58 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We note that aging as well as Fh preparation at a relatively high initial Fe concentration may result in a smaller surface area (Davis and Leckie, 1978). Ferrihydrite, aged 24 h and produced at a relatively high Fe concentration (Girvin et al, 1991), had a lower surface area (450 m 2 /g) when calculated with the above approach. Of Davis (1977) (closed symbols) as given in Dzombak and Morel (1990) and by Hsi and Langmuir (1985) (open symbols).…”

Section: Surface Areamentioning

confidence: 98%

A surface structural model for ferrihydrite I: Sites related to primary charge, molar mass, and mass density

Hiemstra

Riemsdijk

2009

Geochimica et Cosmochimica Acta

237

216

View full text Add to dashboard Cite

Section: Surface Areamentioning

confidence: 98%

A surface structural model for ferrihydrite I: Sites related to primary charge, molar mass, and mass density

Hiemstra

Riemsdijk

2009

Geochimica et Cosmochimica Acta

237

216

View full text Add to dashboard Cite

“…Above that pH, Np sorption onto ferrihydrite increases gradually with increasing pH until pH 8, Np(V) is almost completely sorbed by ferrihydrite at pH 8-10 (Girvin et al 1991). The S-type sorption edge shifts toward lower pH with an increase in the ferrihydrite loading.…”

Section: Neptuniummentioning

confidence: 90%

“…However, because of the inherent uncertainties, it must be recognized that not all of the three digits are significant. It is also noted that some of the references identified the quantities of Fe-oxyhydroxides in units of m 2 /L (e.g., Powell et al 2004, 2005, Sanchez et al 1985 or in M (e.g., Girvin et al 1991, Payne et al 1998, Waite et al 1994, which were converted to units of g/L for use in calculating the K d s. In some cases, the assumptions made to support the unit conversions may have contributed additional uncertainty to the K d values.…”

Section: Approach To Literature Reviewmentioning

confidence: 99%

Literature Review on the Sorption of Plutonium, Uranium, Neptunium, Americium and Technetium to Corrosion Products on Waste Tank Liners

Li¹,

Kaplan²

2012

View full text Add to dashboard Cite

“…Langmuir (1997b) compiles surface complexation constants for actinides and fission products based on several different SCMs. Other compilations are based on the TLM; these include those of Hsi and Langmuir (1985), Tripathi (1983), McKinley et al (1995), , and Lenhart and Honeyman (1999) for uranium; Girvin et al (1991) and Kohler et al (1999) for neptunium; LaFlamme and Murray (1987), Quigley et al (1996), and Murphy et al (1999) for thorium and Sanchez et al (1985) for plutonium. Langmuir (1997b), , Wang et al (2001a, b), and Turner et al (2002) provide references to a large number of other surface complexation studies of radionuclides.…”

Section: Constantsmentioning

confidence: 99%

Environmental Geochemistry of Radioactive Contamination

Siegel

Bryan

2003

Treatise on Geochemistry

View full text Add to dashboard Cite

This report attempts to describe the geochemical foundations of the behavior of radionuclides in the environment. The information is obtained and applied in three interacting spheres of inquiry and analysis: 1) experimental studies and theoretical calculations, 2) field studies of contaminated and natural analog sites and 3) model predictions of radionuclide behavior in remediation and waste disposal. Analyses of the risks from radioactive contamination require estimation of the rates of release and dispersion of the radionuclides through potential exposure pathways. These processes are controlled by solubility, speciation, sorption, and colloidal transport, which are strong functions of the compositions of the groundwater and geomedia as well as the atomic structure of the radionuclides.The chemistry of the fission products is relatively simple compared to the actinides. Because of their relatively short half-lives, fission products account for a large fraction of the radioactivity in nuclear waste for the first several hundred years but do not represent a long-term hazard in the environment. The chemistry of the longer-lived actinides is complex; however, some trends in their behavior can be described. Actinide elements of a given oxidation state have either similar or systematically varying chemical properties due to similarities in ionic size, coordination number, valence, and electron structure. In dilute aqueous systems at neutral to basic pH, the dominant actinide species are hydroxy-and carbonato-complexes, and the solubility-limiting solid phases are commonly oxides, hydroxides or carbonates. In general, actinide sorption will decrease in the presence of ligands that complex with the radionuclide; sorption of the (IV) species of actinides (Np, Pu, U) is generally greater than of the (V) species.The geochemistry of key radionuclides in three different environments is described in this report. These include: 1) low ionic strength reducing waters from crystalline rocks at nuclear waste research 4 sites in Sweden; 2) oxic water from the J-13 well at Yucca Mountain, Nevada, the site of a proposed repository for high level nuclear waste (HLW) in tuffaceous rocks; and 3) reference brines associated with the Waste Isolation Pilot Plant (WIPP). The transport behaviors of radionuclides associated with the Chernobyl reactor accident and the Oklo Natural Reactor are described. These examples span wide temporal and spatial scales and include the rapid geochemical and physical processes important to nuclear reactor accidents or industrial discharges as well as the slower processes important to the geologic disposal of nuclear waste.Application of geochemical information to remediating or assessing the risk posed by radioactive contamination is the final subject of this report. After radioactive source terms have been removed, large volumes of soil and water with low but potentially hazardous levels of contamination may remain. For poorly-sorbing radionuclides, capture of contaminated water and removal of radi...

show abstract

Neptunium adsorption on synthetic amorphous iron oxyhydroxide

Cited by 76 publications

References 24 publications

A surface structural model for ferrihydrite I: Sites related to primary charge, molar mass, and mass density

A surface structural model for ferrihydrite I: Sites related to primary charge, molar mass, and mass density

Literature Review on the Sorption of Plutonium, Uranium, Neptunium, Americium and Technetium to Corrosion Products on Waste Tank Liners

Environmental Geochemistry of Radioactive Contamination

Contact Info

Product

Resources

About