Pretreatment Technology Plan

Barker, Steven A.; Thornhill, C. K.; Holton, L.K.

doi:10.2172/10176465

Cited by 11 publications

(10 citation statements)

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“…The results depicted in Figure 4 show that ~2% of the gross activity came off the column with water, ~1% with 1.0 M HNO 3 , and ~97% with the 8.0 M HNO 3 elution. Although, the 1.0 M HNO 3 dissolved the white Zn(OH) 2 precipitate, very little activity was removed by this eluent; this suggests that the Zn(OH) 2 precipitate is not sorbing the gross activity. When compared to the data in Figure 1, it is clear that Zn 2+ is effecting a decontamination from the gross activity in the waste that is equivalent to adjusting the pH to ~1.…”

Section: De-fg07-01er63281mentioning

confidence: 98%

“…V e is the elution volume. This is the volume that is passed through the column V e = V o + KV i (2) at the point of the concentration maxima of the solute being eluted. V o is the void volume.…”

Section: The Separation Of Werner Type Complexes Using Gel Permeationmentioning

confidence: 99%

“…A precipitate of Zn(OH) 2 was observed. After setting for two hours the solution and white precipitate, Zn(OH) 2 , were added to a Na + form cation column and eluted with the desired amount of water and nitric acid solutions. Sephadex G-10 for gel filtration chromatography of molecules <700 MW was obtained from Aldrich Chemical Company.…”

Section: De-fg07-01er63281mentioning

confidence: 99%

“…2 can be written with K depending on the degree of entry into the pores of the V e = V o + KV i = 13.0 mL + K (5.0 mL) (2) gel and ranging between 0 (no entry) and 1 (total entry). In many of these separations the V e exceeds 18 mL.…”

Section: De-fg07-01er63281mentioning

confidence: 99%

“…1 This characteristic, along with its long half-life, ( 99 Tc, t 1/2 = 213,000 a) makes technetium a major contributor to the long-term hazard associated with low level waste (LLW) disposal. 2 Technetium partitioning from the nuclear waste at DOE sites will be required so that the LLW forms meet DOE performance assessment criteria. Current technetium separations assume that technetium exists as TcO 4 -in the waste.…”

Section: Introductionmentioning

confidence: 99%

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Identification of Non-Pertechnetate Species In Hanford Tank Waste, Their Synthesis, Characterization, And Fundamental Chemistry

Ashely¹,

Schroeder²,

Olivares³

et al. 2004

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Executive SummaryThis proposal had three major goals: (1) develop capillary electrophoresis mass spectrometry as a characterization technique, (2) separate a non-pertechnetate fraction from a waste sample and identify the non-pertechnetate species in it by CEMS, and (3) synthesize and characterize bulk quantities of the identified non-pertechnetate species and study their ligand substitution and redox chemistry.The development of capillary electrophoresis mass spectrometry as a characterization technique for these technetium species was unsuccessful. We were unable to gain access to the necessary instrumental to pursue this aspect of the research. We were able to separate a non-pertechnetate fraction from a waste sample and remove much (>99 %) of the radioactivity. But, we were unable to identify the species(s). We did not have access to the necessary instrumentation. Since we were unable to identify the technetium specie(s), we were unable to synthesize and characterize bulk quantities of the non-pertechnetate species and study their ligand substitution and redox chemistry. The majority of the effort was devoted to devising a separation scheme for the nor-pertechnetate species. We were able to devise a scheme.This report is comprised of three sections. The first is the "Re-Examination of a Procedure for the Analyses of 99 Tc in Hanford Waste Tank Samples." This work was performed to ensure that the analytical procedure that we use for technetium determinations was accurate. The second section reports on the work of the undergraduate students and was performed at TAMUCommerce. It is a detailed investigation of the separation method employed in the section. It is entitled "The Separation of Werner Type Complexes Using Gel Permeation Chromatography." The third part of the report is "Separation of Non-Pertechnetate Species from Hanford AN-107 Tank Waste."The analytical procedure for the analyses of total 99 Tc in an AN-107 Hanford Waste Tank sample has been verified to be accurate and reliable. The general approach of the method was to: (1) add a known amount 95m Tc yield tracer to a sample, (2) oxidize exhaustively the sample with Ce(IV) in HNO 3 , (3) remove the 90 Sr and 137 Cs using a Dowex 50W cation exchange column, (4) adsorb the TcO 4 -onto a Reillex-HPQ anion exchange column, (5) remove the TcO 4 -by reductively elution with a solution of 1 M (NaOH/H 2 NC 2 H 4 NH 2 )/5 mM SnCl 2 , (6) add the eluent to Ultima Gold (UG) liquid scintillation (LS) cocktail, (7) acquire the 95m Tc counts/min (cpm) using a NaI g counter, (8) acquire the 95m Tc and 99 Tc cpm using a LS counter, (9) subtract the 95m Tc LS cpm from the total LS cpm to give the number of LS cpm for 99 Tc. An untreated 95m Tc standard is used to determine the (LS cpm/g cpm ratio for 95m Tc and the chemical yield.The additively of the LS spectra of 99 TcO 4 -and 95m TcO 4 -has been established. There are no serious quenching problems in the determination of the LS cpm in (9 mL water/11 mL UG) to (1 mL water/19 mL UG) and and with various amounts...

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Section: De-fg07-01er63281mentioning

confidence: 98%

Section: The Separation Of Werner Type Complexes Using Gel Permeationmentioning

confidence: 99%

Section: De-fg07-01er63281mentioning

confidence: 99%

Section: De-fg07-01er63281mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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