The pyro- and hydrometallurgical processing of uranium-containing waste

Reddy, Ramana G.

doi:10.1007/s11837-001-0157-x

Cited by 3 publications

(2 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently, a number of different treatment methods have been applied to reduce the volume of liquid radioactive waste particularly related to LLRW as well as to remove radionuclides from the waste, such as thermal treatment, extraction, sorption, ion exchange, electrolytic reduction, and membrane separation ( − ). Thermal processes including evaporation, incineration, and vitrification helped increase the solids content of the waste considerably, and thermal treatment in combination with vitrification or wet oxidation has also been carried out for volume reduction and hazards control depending on the characteristics of the radioactive waste ( 8−10 , 20 , 21 ).…”

Section: Introductionmentioning

confidence: 99%

“…The supercritical fluid extraction method is still in the early stage of evaluation and requires an extreme operating condition in pressure and temperature. Several different sorbents such as zeolite, activated carbon, and microorganisms have been investigated in terms of decontamination of the liquid wastes and concentration of radioactive species (13)(14)(15)(25)(26)(27)(28)(29). The adsorption methods are confronting some issues yet to be solved, such as selectivity, regeneration, and sludge production.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Selective Removal of Cobalt Species Using Nanofiltration Membranes

Choo

Kwon

Lee

et al. 2002

Environ. Sci. Technol.

View full text Add to dashboard Cite

Selective removal of cobalt species from simulated nuclear liquid waste was investigated with different nanofiltration (NF) membranes at various solution pH levels, initial cobalt concentrations, and background ion concentrations. This study provides insight into the understanding of the relationships between rejections of a target compound (cobalt) and chemical equilibria of various species in the feed solution during NF. Particularly, the ratio of electrostatic rejection to steric rejection for different membranes used was quantitatively evaluated to find outthe relative significance in NF. Substantial cobalt rejection by NF was achieved along with partial separation of monovalent ionic species, although it depended on the level of liquid pH and the presence of background species. Greater cobalt rejection at increased pH was attributed to the precipitation of CoCO3(s) associated with natural carbonates originating from atmospheric CO2 gas rather than that of Co(OH)2(s). A loose NF membrane (e.g., NTR7410) gave as high a rejection as other tighter ones due to the stronger influence of electrostatic rejection, particularly at low pH where no cobalt precipitation was occurring. The decrease of cobalt rejection with the addition of boric acid was found to occur due to the formation of complexes between cobalt and boric acid, which was verified by the analyses of solution turbidity and near-infrared spectroscopy.

show abstract