A synergistic extraction mixture containing chlorinated cobalt dicarbollide (CCD), carbamoylmethyl phosphine oxide (CMPO), and polyethylene glycol (PEG) has been investigated for the simultaneous recovery of cesium, strontium, lanthanides, and actinides from highly acidic media. The extraction properties of this mixture depend on the concentration ratio of the components. For recovery of all major radionuclides, the optimal ratio of [CCD]:[PEG]: [CMPO] = 5:1:1 should be used. The use of diphenyl-N,N-dibutylcarbamoylmethyl phosphine oxide and PEG-400 provides the most efficient recovery of cesium, strontium, lanthanides, and actinides. The possibility of using polyfluorinated ethers, esters, ketones, and sulfones as diluents was examined. Phenyltrifluoromethyl sulfone was the most suitable diluent tested. The use of this diluent allows good extraction properties, chemical and radiation stability, excellent explosion/fire-safety properties, and favorable hydrodynamic characteristics. The extraction of radio...

The universal solvent extraction (unex) process. i. development of the unex process solvent for the separation of cesium, strontium, and the actinides from acidic radioactive waste

Applications of the dicarbollylcobaltate(III) anion in the water/nitrobenzene extraction system.

A novel solvent extraction process, the Universal Extraction (UNEX) process, has been developed for the simultaneous separation of cesium, strontium, and the actinides from acidic waste solutions. The UNEX process solvent consists of chlorinated cobalt dicarbollide for the extraction of 137Cs, polyethylene glycol for the extraction of 90Sr, and diphenyl-N,N-dibutylcarbamoyl phosphine oxide for the extraction of the actinides and lanthanides. A nonnitroaromatic polar diluent consisting of phenyltrifluoromethyl sulfone has been developed for this process. A UNEX flowsheet consisting of a single solvent extraction cycle has been developed as a part of a collaborative effort between the Khlopin Radium Institute (KRI) and the Idaho National Engineering and Environmental Laboratory (INEEL). This flowsheet has been demonstrated with actual acidic radioactive tank waste at the INEEL using 24 stages of 2-cm diameter centrifugal contactors installed in a shielded cell facility. The activities of 137Cs, 90Sr, and th...

The universal solvent extraction (unex) process. ii. flowsheet development and demonstration of the unex process for the separation of cesium, strontium, and actinides from actual acidic radioactive waste

Electrolysis with electrolyte dropping electrode: II. Basic properties of the system

A principal purpose of this paper is to call out what is perceived to be a timely need for increased research to develop improved and new solvent extraction technology for recovery of 137Cs and 90Sr from strong (≥ 0.5M HNO3) acid media, technology which can be quickly scaled up to routine plant-scale operation with highly radioactive waste solutions when needed. The present and forseeable future (2020) U.S. inventory of 137Cs and 90sr is listed; much of this inventory is expected to be available only in strongly acidic nuclear waste solutions. Comparison of available methods-precipitation and ion exchange as well as solvent extraction—for recovering 137 Cs and 90Sr from alkaline and acid media demonstrates, as expected, that very limited technology is available for use with strongly acidic solutions. Solvent extraction procedures which employ either macrocyclic polyethers (crown ethers) or dicarbolide. H+{[π-(3)-1, 2-B9C2H11Cl2±2Co}−, to extract 137Cs and 90Sr from ≥ 0.5M HNO3 solutions have rece...

P. Selucký

Papers

Extraction of alkali metals into nitrobenzene in the presence of univalent polyhedral borate anions

Synergistic effect of polyethylenglycols in extraction of alkaline earth cations by nitrobenzene

Temperature dependence of the extraction of alkali metal dipicrylaminates into nitrobenzene

Novel applications of dipicrylamine as an extractant in the determination of alkali metals