EXTRACTION OF MOLYBDENUM FROM NITRIC ACID BY OCTYL(PHENYL)-N,N-DIISOBUTYLCARBAMOYLMETHYL-PHOSPHINE OXIDE

Abstract

The extraction behavior of molybdenum(VI) under the conditions of transuranium extraction (TRUEX) process was studied by using octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide. The extraction behavior of molybdenum(VI) under the condition of PUREX process was also investigated for comparison. The extraction of molybdenum with the copresence of uranium(VI), dysprosium(III), and the effect of oxalic acid were examined. Under the PUREX conditions, molybdenum was less extractable, while under the TRUEX process conditions, a higher distribution ratio of molybdenum was observed. Under the TRUEX conditions, the addition of oxalic acid was effective in depressing molybdenum extraction. It was concluded that, at the concentration of nitric acid ORDER REPRINTS 128FUJII ET AL.around 1 mol dm −3 or higher, Mo(VI) is extracted predominantly as cationic species, while at lower concentration of nitric acid, the coextraction of anionic molybdenum as a mixed complex with other metal, that is, UO 2+ 2 , occurs.

Adsorption of Molybdenum Ion in Nitric Acid Solution by Using a Pb-Fe Based Adsorbent

“…Since the incorporation of Mo is of particular concern in the vitrification of HLLW, Fujii et al [9] investigated the extraction of Mo by using octyl(phenyl)-N,N-diisobutylcarbamoylmethylphos phine oxide, whereas Zhang et al [8] synthesized a macroporous silica-based octyl(phenyl)-N,N-diisobutylcarbamoylmethylph osphine oxide impregnated polymeric composite to eliminate Mo from HLLW. Although the above mentioned composites can extract Mo from the HLLW, other materials, such as a Pb-Fe based adsorbent, could be a feasible alternative, [10,11].…”

Sasse Modeling of a Uranium Molybdenum Separation Flowsheet

“…Distribution coefficients for Mo(VI) have been measured by Vorob'ev et al, 26 Fujii et al, 27 and Visser and Pierce. 28 These distribution coefficients are compared with distribution coefficients fitted to the DFs reported for the small scale Hallam and Piqua fuel tests, listed in Table 3 Three separate SASSE models were constructed using Mo(VI) distribution coefficients based on the Hallam, the Piqua, and the Visser and Pierce data.…”

Reprocessability of molybdenum and magnesia based inert matrix fuels

“…Cationic species exist in the region of pH below one. In the acidic region, the existence of dimeric cations has been suggested in the more concentrated solutions of molybdenum [34]. The speciation of molybdenum during dissolution of molybdenum pellets was studied by electrospray ionization mass spectrometry (ESI-MS), but is beyond the scope of this paper and will be published elsewhere.…”