Hostname: page-component-848d4c4894-p2v8j Total loading time: 0.001 Render date: 2024-05-22T00:20:59.112Z Has data issue: false hasContentIssue false
  • English
  • Français

Leaching of Saltstone

Published online by Cambridge University Press:  26 February 2011

Mary W. Barnes ,
Christine A. Langton  and
Della M. Roy
Mary W. Barnes
Affiliation:
The Pennsylvania State University, Material Research Laboratory, University Park, Pennsylvania 16802
Christine A. Langton
Affiliation:
E. I. du Pont de Nemours and Company, Savannah River Laboratory, Aiken, South Carolina 29808
Della M. Roy
Affiliation:
The Pennsylvania State University, Material Research Laboratory, University Park, Pennsylvania 16802
Get access

Abstract

A modified IAEA leach test was used to evaluate the relative performance of potential saltstone formulations. The effects of sample size and leach rates for specific ions were determined. Leaching mechanisms were determined for NO3−, NO2−, SO4−2, Na+, Ca+2 and Si.

NO2−, NO3−, Na+ and SO4−2 are listed in order of decreasing leach rates. These ions exhibited high initial leach rates which decreased rapidly with time. High initial rates were attributed to surface wash off and diffusion. Within 10 days leach rates stabilized and can be explained by diffusion. Effective diffusivities for nitrite, nitrate, sodium, and sulfate were calculated from the leaching data. They are 6.4 × 10−10, 4.1 × 10−10, 3.2 × 10−10, and 0.9 × 10−10 cm2 /sec, respectively.

Negative leach rates were measured for Ca+2 and Si in some formulations. This was attributed to precipitation of CaCO3 and hydrated calciumsilicate phases on the surfaces of the samples.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 44: Symposium N – Scientific Basis for Nuclear Waste Management VIII , 1984 , 865
Copyright
Copyright © Materials Research Society 1985

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Langton, C. A., Dukes, M. D., and Simmons, R. V., “Cement-Based Waste Forms for Disposal of Savannah River Plant Low-Level Radioactive Salt Waste,” Sci. Basis for Nuclear Waste Management 1, McVay, G. L., ed., North Holland, NY, 1984.Google Scholar
2. Barnes, M. W., Scheetz, B. E., Wakeley, L. D., Atkinson, S. D., and Roy, D. M., “Stability of I and Sr Radiophases in Cement Matrices,” Sci. Basis for Nuclear Waste Management, 4, Topp, S. V., ed., 1982.Google Scholar
3. Langton, C. A., “Physical Properties of Saltstone: A Savannah River Plant Waste Form,” Proceedings, this symposium, 1985.Google Scholar
4. Crank, J., Mathematics of Diffusion. Chapters 5 and 11, pp 62–83 and 219–257, Oxford University Press, London, 1956.Google Scholar