skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Efficacy of soluble sodium tripolyphosphate amendments for the in-situ immobilisation of uranium

Authors:
; ;
Publication Date:
Research Org.:
Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER)
OSTI Identifier:
1152540
Resource Type:
Journal Article
Resource Relation:
Journal Name: ENVIRONMENTAL CHEMISTRY; Journal Volume: 4; Journal Issue: 5
Country of Publication:
United States
Language:
English

Citation Formats

Wellman, DM, Pierce, EM, and Valenta, MM. Efficacy of soluble sodium tripolyphosphate amendments for the in-situ immobilisation of uranium. United States: N. p., 2007. Web.
Wellman, DM, Pierce, EM, & Valenta, MM. Efficacy of soluble sodium tripolyphosphate amendments for the in-situ immobilisation of uranium. United States.
Wellman, DM, Pierce, EM, and Valenta, MM. Mon . "Efficacy of soluble sodium tripolyphosphate amendments for the in-situ immobilisation of uranium". United States. doi:.
@article{osti_1152540,
title = {Efficacy of soluble sodium tripolyphosphate amendments for the in-situ immobilisation of uranium},
author = {Wellman, DM and Pierce, EM and Valenta, MM},
abstractNote = {},
doi = {},
journal = {ENVIRONMENTAL CHEMISTRY},
number = 5,
volume = 4,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • A series of conventional saturated and pressurized unsaturated flow (PUF) column experiments were conducted to evaluate the effects of utilizing soluble polyphosphate amendments for in situ, subsurface remediation of uranium. Experiments were conducted under mildly alkaline, calcareous conditions, representative of conditions commonly encountered at sites across the arid western United States. Results presented here illustrate that application of a soluble polyphosphate amendment to sediment contaminated with uranium will rapidly reduce the concentration of uranium to near or below drinking water limits under water saturated and unsaturated conditions. Column experiment conducted in the absence of polyphosphate illustrate sustained release of aqueousmore » uranium at concentrations well above drinking water standards in excess of over 25 pore volumes under saturated conditions and over 50 pore volumes under water unsaturated conditions. However, in the presence of tripolyphosphate the concentration of aqueous uranium released from sediment was near or below drinking water limits within 10 to 35 pore volumes under saturated and unsaturated conditions, respectively. Moreover, results indicate the necessity of conducting site specific dynamic tests in order to tailor phosphate remediation technology based relevant geochemical and hydrological conditions.« less
  • A polarographic method of estimating of uranium, based on the reduction of its tripolyphosphate complex at the dropping mercury electrode has been developed and applied to uraniferous tantaloniobates and monazite. In the presence of elements such as copper, iron, and vanadium which interfere with the cathodic step of the uranyl complex, a preliminary separation as uranyl ammoniura phosphate in presence of EDTA is necessary. (auth)
  • The U(IV) and U(VI) contents of a sample can be determined by controlled-potential coulometric titration. Both the oxidation and reduction reactions take place at a mercury pool electrode in a supporting electrolyte that is 8 w/v% sodium tripolyphosphate solution adjusted to pH 7.5 to 9.5. The U(VI) is reduced coulometrically at a potential of -1.35 volts vs S.C.E. The reduction is a direct measure of the U(VI) present. The same test portion is then oxidized coulometrically at +0.1 volt vs S.C.E. The oxidation is a measure of the total U present; the U(IV) content is found by difference. In themore » range of total U content from 2 to 10 mg, the error of the method is approximately 1%. Various possible interferences were studied; only Cu(II) and Fe(III) caused any significant error. (auth)« less
  • The behavior of some tripolyphosphate complexes at the dropping mercury electrode has been examined, in particular that of the uranyl tripolyphosphate complex. The uranyl ion in alkaline tripolyphosphate medium undergoes an irreversible one-electron reduction. Indifferent salts shift the E/sup 1/2 to more positive potentials whereas maximum suppressors have an opposite effect. The wave obtained in presence of 0.01% camphor is well-defined and suitable for use in uranium analysis. (auth)
  • The anodic behavior of U(IV) at the D.M.E. in a sodium tripolyphosphate- sodium suifate medium as studied. In this medium, U(IV) exhibits an anodic wave whose E/sup 1/2/ is -0.19 volt vs S.C.E. and whose i/sub d/ is proportional to the U(IV) concentration. The proper conditions for analytical use of the anodic wave were established, and the effects of pH and uranium concentration were studied. The best results were obtained in a 6 w/v % Na/sub 5/P/sub 3/O/sub 10/- 0.1 M Na/sub 2/SO/sub 4/ medium of pH 9. The error of the U(IV) determination was about plus or minus 3%.more » The U(VI) content of a sample may also be determined by measurement of the U(VI) cathodic wave at -1.1 volts vs S.C.E. in the medium. Possible interferences by various cations and anions were studied. Of the ions studied, only Fe(II) interfered to any extent. (auth)« less