Dissolution of Fb-Line Metal Residues Containing Beryllium in H-Canyon

Rudisill, Tracy S.; Crowder, Mark L.; Bronikowski, Michael G.

doi:10.2172/895966

Cited by 7 publications

(20 citation statements)

References 3 publications

(4 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Testing with B instead of Gd yielded flowsheets that were able to dissolve at 20 mg/min-cm 2 . The precipitation issue associated with Gd does not exist for B at the concentrations tested (1-2 g/L B).…”

Section: Dissolution Rate Measurementsmentioning

confidence: 99%

“…This observation supports our conclusion that either 1 g/L Gd or B in the dissolving solution had the same general effect on the dissolution rate. Rudisill [1] reported that 0.17 and 0.48 mole offgas/mole Pu were collected during two sample periods when a dissolution was performed using 4 M HNO 3 solution containing 0.1 M KF at 80°C. The lower offgas generation is likely due to the different dissolution mechanisms which predominate at low (4 M) and high (10 M) HNO 3 concentrations.…”

Section: Offgas Generationmentioning

confidence: 99%

“…ICPES (1) Prep. ICPES (1) Prep. The free acid concentrations of the Pu metal dissolving solutions were analyzed by titration.…”

Section: Table 3-12 Analysis Of Pu Metal Dissolving Solutionsmentioning

confidence: 99%

“…[1][2][3][4][5][6][7] However, most of the testing was conducted at HNO 3 concentrations in the 3-5 M range and at temperatures < 90 C to limit the formation of plutonium dioxide and maximize the rate of dissolution. To support a new mission in H-Canyon, the development of a Pu metal dissolution flowsheet which utilizes 8-10 M HNO 3 solutions containing KF is desired.…”

Section: Introductionmentioning

confidence: 99%

“…[8][9] The preferred flowsheet would use 8-10 M HNO 3 . [7] Based on Holcomb's calculations, a nominal alpha phase button would require a cumulative dissolution rate of ~20 mg/min-cm 2 to dissolve within 24 hours. Materials with higher surface areas will dissolve faster than a nominal button.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Dissolution of Plutonium Metal in 8-10 M Nitric Acid

Rudisill¹,

Pierce²

2012

View full text Add to dashboard Cite

Section: Dissolution Rate Measurementsmentioning

confidence: 99%

Section: Offgas Generationmentioning

confidence: 99%

“…ICPES (1) Prep. ICPES (1) Prep. The free acid concentrations of the Pu metal dissolving solutions were analyzed by titration.…”

Section: Table 3-12 Analysis Of Pu Metal Dissolving Solutionsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Dissolution of Plutonium Metal in 8-10 M Nitric Acid

Rudisill¹,

Pierce²

2012

View full text Add to dashboard Cite

Low temperature dissolution flowsheet for Pu metal

Daniel

Almond

Rudisill

2017

Separation Science and Technology

View full text Add to dashboard Cite

The Savannah River National Laboratory was requested to develop a Pu metal dissolution flowsheet at two reduced temperature ranges for implementation in the Savannah River Site H-Canyon facility. The dissolution and H 2 generation rates during Pu metal dissolution were investigated using a dissolving solution at ambient temperature (20-30 °C) and for an intermediate temperature of 50-60 °C. The Pu metal dissolution rate measured at 57 °C was approximately 20 times slower than at boiling (112 -116 °C). The dissolution rate at ambient temperature (24 °C) was approximately 80 times slower than the dissolution rate at boiling Hydrogen concentrations were less than detectable (<0.1 vol %). Low Temperature Dissolution Flowsheet for Pu Metal SRNL-STI-2016-00524 page 19 of 26 * Estimated dissolution rate(1) **Dissolving solution also contained 0.4 g/L Ni and 0.6 g/L Cr

show abstract

Dissolution of Plutonium Metal in 8-10 M Nitric Acid

Rudisill¹,

Pierce²

2012

View full text Add to dashboard Cite

The H-Canyon facility will be used to dissolve Pu metal for subsequent purification and conversion to plutonium dioxide (PuO 2) using Phase II of HB-Line. To support the new mission, the development of a Pu metal dissolution flowsheet which utilizes concentrated (8-10 M) nitric acid (HNO 3) solutions containing potassium fluoride (KF) is required. Dissolution of Pu metal in concentrated HNO 3 is desired to eliminate the need to adjust the solution acidity prior to purification by anion exchange. The preferred flowsheet would use 8-10 M HNO 3 , 0.015-0.07 M KF, and 0.5-1.0 g/L Gd to dissolve the Pu up to 6.75 g/L. An alternate flowsheet would use 8-10 M HNO 3 , 0.1-0.2 M KF, and 1-2 g/L B to dissolve the Pu. The targeted average Pu metal dissolution rate is 20 mg/min-cm 2 , which is sufficient to dissolve a "standard" 2250-g Pu metal button in 24 h. Plutonium metal dissolution rate measurements showed that if Gd is used as the nuclear poison, the optimum dissolution conditions occur in 10 M HNO 3 , 0.04-0.05 M KF, and 0.5-1.0 g/L Gd at 112 to 116 C (boiling). These conditions will result in an estimated Pu metal dissolution rate of ~11-15 mg/min-cm 2 and will result in dissolution times of 36-48 h for standard buttons. The recommended minimum and maximum KF concentrations are 0.03 M and 0.07 M, respectively. The maximum KF concentration is dictated by a potential room-temperature Pu-Gd-F precipitation issue at low Pu concentrations. Testing at 8-10 M HNO 3 , 0.1-0.2 M KF, and 1-2 g/L B demonstrated that ~20-35 mg/min-cm 2 Pu metal dissolution rates can be achieved at 112 to 116 C (boiling). The concentration of B in solution did not have a significant effect on dissolution rate. The data also indicate that lower KF concentrations would yield dissolution rates for B comparable to those observed with Gd at the same HNO 3 concentration and dissolution temperature. The low-temperature Pu precipitation issue associated with the use of Gd does not occur for dissolution with B; however, the B concentration must be maintained below the H 3 BO 3 solubility limit and the KF concentration must not exceed the value where B precipitates as KBF 4. To confirm that the optimal conditions identified by the dissolution rate measurements can be used to dissolve Pu metal up to 6.75 g/L in the presence of representative concentrations of Fe and Gd or B, a series of experiments was performed to demonstrate the flowsheets. In three of the five experiments, the offgas generation rate during the dissolution was measured and samples were analyzed for hydrogen gas (H 2). The use of 10 M HNO 3 containing 0.03-0.05 M KF, 0.5-1.0 g/L Gd, and 1.9 g/L Fe resulted in complete dissolution of the metal in 2.0-3.5 h. When B was used as the neutron poison, 10 M HNO 3 solutions containing 0.05-0.1 M KF, 1.9 g/L Fe, and 1 g/L B resulted in complete dissolution of the metal in 0.75-2.0 h. All experiments were performed using a dissolution temperature of 100 C. No residues were observed following the dissolutions in either the Gd or B system. Dissolut...

show abstract

Dissolution of Fb-Line Metal Residues Containing Beryllium in H-Canyon

Cited by 7 publications

References 3 publications

Dissolution of Plutonium Metal in 8-10 M Nitric Acid

Dissolution of Plutonium Metal in 8-10 M Nitric Acid

Low temperature dissolution flowsheet for Pu metal

Dissolution of Plutonium Metal in 8-10 M Nitric Acid

Contact Info

Product

Resources

About