Waste separation from high activity

Madic, C., Lecomte, M., Dozol, J.F., Boussier, H. 2004. Advanced chemical separations of minor actinides from high active nuclear wastes. EURADWASTE 04, Luxembourg, Belgium, March 24 to April 1. 

Apostilidos, C., Meester, R., de Koch, L. et al. 1990. The extraction of actinides and other constituents from highly-active waste (HAW) by trialkyl phosphine oxide (TRPO). Technical seminar on new separation chemistry techniques for radioactive waste and other specific applications, Rome (Italy), May 16-18. EUR-13390-EN. 

Apostolidis, C. Meester, R. De. Koch, L. Molinet, R. Liang, J. Zhu, Y. The Extraction of Actinides and Other Constituents from Highly Active Waste (HAW) by Triallkyl Phosphine Oxide. In New Separation Techniques for Radioactive Waste and Other Specific Applications, L. Cecille, M. Casa, and L. Pietrelli (Eds.), Elsevier Applied Science, Rome Italy (1990), p. 80. 

However, due to the chemical similarities of the trivalent actinide and lanthanide elements, historically, it has been easier to develop step-by-step processes first, An(III) + Ln(III) coextraction processes, which also address the problem of waste alpha decontamination, and second, An(III)/Ln(III) separation processes, which can only be implemented on the solutions produced by the first-step processes. Today, however, a few processes are available that allow recovery of the trivalent actinides in a single step from highly active liquid waste. 

Madic, C., Lecomte, M., Baron, P., Boullis, B. Separation of long-lived radionuclides from high active nuclear waste. C.R. Physique (2002), 3 (7-8), 797-811. 

Mannone, F., Dwoschak, H. 1984. Chemical separation of actinides from high activity liquid wastes - Final report. JRC Ispra Report, S.A./l. 07.03.84.02. 

Mousty, F. Toussaint, J. Godfrin, J., "Separation of Actinides from High Activity Waste. The Oxal Process," Radiochem. Radioanal. Lett., 1977, 31, 918. 

Separation of Actinides from High Active Waste by Means of Counter Current Ion Migration... 

An example of a SI separation system is shown in Figure 9.2.44 The column is followed by a diverter valve so that the column effluent can be sent to waste during sample load and wash steps. This approach prevents matrix components and high-activity interferences from fouling the detector. During the elution of the radionuclide... 

Separation of Actinides from Purex-Type High Active Waste Raffinates... 

The use of nuclear power as energy source is determined by the safe handling and deposition of the nuclear waste. High active waste solutions must be transformed into stable solid form which is suitable for final disposal. The separation of the actinides from the waste before its solidification (e.g. vitrification) is advantageous (or may be even necessary) from two points of view ... 

Characterization of Volatile Fraction. Volatile organic compounds found in oily wastewaters consist primarily of lower-molecular-weight aliphatic and aromatic hydrocarbons. Because of its relatively high vapor pressure, this fraction is quite often lost during analysis of oily wastes. For this reason a separate procedural step was incorporated into the overall scheme for analysis of the volatile fraction. An unfiltered sample of oily waste is used in this determination. The volatile fraction is separated from water by means of nitrogen sparging and collected in an activated carbon absorption column. The collected compounds are desorbed into carbon disulfide and analyzed by GC. 

To rather selectively separate pertechnetate, with more than 90 % yield, from solutions of acid fission products it was proposed to use finely divided cadmium sulphide. The overall yield of the radionuclide pure c, finally extracted as [(C(,H5)4As TcC)4, was 68 % [182,183]. In addition, activated carbon was used to efficiently separate pertechnetate from high-level liquid waste. Distribution coefficients of more than 500 were observed when pertechnetate was separated with activated carbon from a 2 M HNO3 solution [184]. Effective separation and recovery of Tc04 from contaminated groundwater with activated carbon have been reported very recently [185. ... 

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