Mechanism of Phosphorus Removal from Hanford Tank Sludge by Caustic Leaching

Lumetta, Gregg J.

doi:10.2172/934407

Cited by 7 publications

(14 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results are in agreement with the previous studies demonstrating that high concentrations of NaOH produced high levels of surface erosion of polymers, with a concomitant increase in roughness . Lumetta has shown that TCP was leached slightly by ∼4% under a vigorous alkaline hydrolysis condition (3.11 M NaOH). However, in the current study, the EDX data demonstrated a significant reduction of Ca content on the HPBSu/TCP surfaces under hydrolysis treatment.…”

Section: Discussionsupporting

confidence: 93%

Stem cell adhesion and proliferation on hydrolyzed poly(butylene succinate)/β‐tricalcium phosphate composites

Patntirapong

Singhatanadgit

Meesap

et al. 2014

J Biomedical Materials Res

View full text Add to dashboard Cite

Although poly(butylene succinate)/β-tricalcium phosphate (PBSu/TCP) composites are biocompatible and allow the growth and osteogenic differentiation of stem cells, cell attachment and adhesion to the PBSu-based substrates is often limited. To enhance cell adhesion and proliferation, we used a sodium hydroxide (NaOH) hydrolysis technique to generate a different degree of roughness on PBSu/TCP substrates with different PBSu:TCP ratios. The results showed that NaOH hydrolysis increased surface roughness of PBSu/TCP substrates in a concentration-dependent manner. Substrates with higher ratios of TCP:PBSu provided more porous topography after NaOH hydrolysis, with a substrate containing 40 wt % TCP (PBSu/TCP-6040) hydrolyzed with 1.5M NaOH (HPBSu/TCP-6040-1.5) showing the highest degree of roughness. As with the roughness, PBSu/TCP surface hydrophilicity was positively affected by the increasing NaOH concentration and TCP incorporation. Stem cells adhered best on HPBSu/TCP-6040-1.5 with three-dimensionally elongated cell extensions. Moreover, the HPBSu/TCP-6040-1.5 substrate most significantly facilitated stem cell actin cytoskeleton reorganization and vinculin-positive focal adhesion formation when compared with the other substrates tested. HPBSu/TCP-6040-1.5 also demonstrated the greatest increase in cell proliferation when compared with the other substrates studied. In conclusion, the results have shown that among various substrates tested, HPBSu/TCP-6040-1.5 provided the best support for stem cell adhesion and proliferation, suggesting its potential use in bone engineering.

show abstract

Section: Discussionsupporting

confidence: 93%

Stem cell adhesion and proliferation on hydrolyzed poly(butylene succinate)/β‐tricalcium phosphate composites

Patntirapong

Singhatanadgit

Meesap

et al. 2014

J Biomedical Materials Res

View full text Add to dashboard Cite

show abstract

“…These observations indicate that 75 to 85% of the Al present in the washed Group 1 solids was present in a form that is readily dissolved in caustic media. Candidate phases that would explain this behavior include gibbsite (or amorphous aluminum hydroxide) and aluminum phosphate (Lumetta 2008). Definitive identification of the specific Al-containing phases was vitiated by the relatively low concentration of Al in the sample.…”

Section: Group 1 Solidsmentioning

confidence: 99%

Characterization, Leaching, and Filtration Testing for Bismuth Phosphate Sludge (Group 1) and Bismuth Phosphate Saltcake (Group 2) Actual Waste Sample Composites

Lumetta¹,

Buck²,

Daniel³

et al. 2009

Self Cite

View full text Add to dashboard Cite

“…Soluble phosphorus accounts for 38 wt% of the original Group 7 slurry P content ( Figure 5.36) and can be directly attributed to phosphates. It is believed that the portion of the P that appears as solid in the slurry is either a result of gelling (WTP-RPT-173 [Lumetta 2008]) or PO 4 entrainment in solids. The phosphorus content of the AY102 slurry was relatively low (Coleman 2003), so the addition was not expected to contribute to the total inventory of the blended slurry.…”

Section: Caustic Batch Rinsing Resultsmentioning

confidence: 99%

Characterization, Leaching, and Filtration Testing for Tributyl Phosphate (TBP, Group 7) Actual Waste Sample Composites

Edwards¹,

Billing²,

Blanchard³

et al. 2009

View full text Add to dashboard Cite

The tributyl phosphate sludge (TBP, Group 7) is the subject of this report. The Group 7 waste was anticipated to be high in phosphorus as well as aluminum in the form of gibbsite. Both are believed to exist in sufficient quantities in the Group 7 waste to address leaching behavior. Thus, the focus of the Group 7 testing was on the removal of both P and Al. The waste-type definition, archived sample conditions, homogenization activities, characterization (physical, chemical, radioisotope, and crystal habit), and caustic leaching behavior as functions of time, temperature, and hydroxide concentration are discussed in this report. Testing was conducted according to TP-RPP-WTP-467. ObjectivesThe test objectives are summarized in Table S.1 along with a discussion of how the objectives were met. Several objectives (in gray shading lighter than header shading) did not specifically apply to the scope provided in this report; they will be reported in companion reports as indicated in the controlling test plan. Y Group 7 contained a significant amount of P. The P behavior for the Group 7 composite during caustic leaching was characterized as a function of time, temperature, and free-hydroxide concentration.The P removal results can be found in Sections 3, 4, and 5.6) Determine the ultrafiltration flux before and after caustic and oxidative leaching over the operating range of solids concentrations during the leaching processes at 25°C when sufficient actual waste sample is available for testing the filtration behavior.Y Ultrafiltration (CUF) testing was performed on the Group 7 solids. The CUF testing was performed before leaching using slurries with both low-and high-solids contents. The high-solids slurry was obtained by blending wastes from AY-102 with the Group 7 slurry. Further CUF testing was performed after caustic leaching. During these tests, the ultrafiltration flux was determined as a function of transmembrane pressure and axial velocity. The CUF tests were conducted at ambient temperature. There was no oxidative leach performed on this waste type; therefore, there was no CUF testing done on post oxidative-leach materials.All the CUF testing results are discussed in Section 5. The solids characterization results are distributed throughout the report at the specific relevant sections. Test ExceptionsNo test exceptions applied to this work. Results and Performance Against Success CriteriaThe test plan delineated several success criteria, which are listed in Table S.2. Selected criteria were relevant to the test scope included in this report; the other criteria that are outside of the reported scope are shaded. Not applicable. The Group 7 sample did not have significant amounts of boehmite.5) The dissolution rate and the extent of dissolution of chromium in the actual waste solids are determined as a function of temperature and over a range of NaOH concentrations of interest to oxidative leaching. The NaMnO 4 dosage will be predetermined for the oxidation of the chromium in the waste solids. The associated uncert...

show abstract

Mechanism of Phosphorus Removal from Hanford Tank Sludge by Caustic Leaching

Cited by 7 publications

References 12 publications

Stem cell adhesion and proliferation on hydrolyzed poly(butylene succinate)/β‐tricalcium phosphate composites

Stem cell adhesion and proliferation on hydrolyzed poly(butylene succinate)/β‐tricalcium phosphate composites

Characterization, Leaching, and Filtration Testing for Bismuth Phosphate Sludge (Group 1) and Bismuth Phosphate Saltcake (Group 2) Actual Waste Sample Composites

Characterization, Leaching, and Filtration Testing for Tributyl Phosphate (TBP, Group 7) Actual Waste Sample Composites

Contact Info

Product

Resources

About