Liquid–liquid extraction of neodymium (III) and europium (III) using synergic mixture of furosemide and tribenzylamine in benzyl alcohol

Liquid-liquid extraction of Nd+3 and Eu+3 from aqueous medium using oxytetracycline in dichloromethane

Liquid-liquid extraction system consisting of oxytetracycline (HOTC) in dichloromethane was developed for extraction of Nd+3 and Eu+3 from acidic solutions using radiometric technique. Various extraction parameters such as pH, equilibration time and metals concentration were optimized. Slope analysis method was used to study the composition of product and was found to be M(OTC)3 [here M=Nd+3 or Eu+3 and OTC = conjugate base of HOTC]. Among cations Al+3 and Fe+3 while among anions F− effected the extraction of these metals. Higher separation factor of these metals was found with many others. The method was successfully applied on spiked sea water.

Synergistic Extraction of Europium (III) using Di-n-Butylsulfoxide and PicrolonicAcid

AIM AND OBJECTIVE

Europium (Eu(III))isa rare-earth metal, the softest, least dense, and most volatile member of lanthanides. It is greatly applied in control rods of nuclear reactors. Although various extraction methods of Eu(III)have been reported, we present a novel mixture ofeasily available extractants in optimizedexperimental conditions to extract it efficiently, quickly, and cost-effectively.

MATERIALS AND METHODS

Physical-chemical conditions (e.g. pH, equilibration time, temperature, europium concentration, extractants concentration, presence of specific metal ions) were optimized. The extractantspicrolonic acid (HPA) and di-n-butylsulfoxide (DBSO) were thoroughly mixed at equal concentrationin chloroform. Standard Eu(III) solution was used for method accuracy.Reagent blank was prepared under identical conditions but without metal ions.Using the metallochromic dye arsenazoIII as blank, absorbance of Eu(III) was measured spectrophotometricallyat 651 nm. Distribution ratio (i.e.Eu(III) concentration in aqueous phase before and after extraction) defined the extraction yield.

RESULTS

HPA/DBSO mixture (0.01 M)had a synergistic effect on Eu(III) extraction (1.19×10-5 mole/dm3) achieving a maximum yield (≥99%) at pH2, during 5 minutes equilibration,atroom temperature.Eu(III) extraction was reduced depending on the nature but not on the metal ions concentration. Extractants could be recycled four times without consequent degradation. Deionized water (dH2O) was the best strippantbesides its availability and low-cost. The composition of the extracted adduct was defined as Eu(PA)3.2DBSO.

CONCLUSION

This alternative method was stable, simple, rapid, cost-effective, reliable, accurate and sensitive.It could be used forEu(III) extraction and refining on a pilot plant scale.

Continuous Extraction of Europium(III) by Ionic Liquid in the Rotating Disk Column with an Asymmetrical Structure Aimed at the Evaluation of Reactive Mass Transfer

In this study, the features of the solvent extraction technique were investigated to explore the potential of ionic liquid for extracting Eu(III) from aqueous solution. The transport process between the aqueous and organic phase was carried out in the rotating disk column with an asymmetrical structure and a continuous mode of operation. The utilization of Cyphos IL 104 as an ionic liquid in comparison with Cyanex272 extractant was evaluated for the extraction abilities in the recovering of Eu(III) under different conditions, including agitation speed, inlet aqueous, and solvent phase velocities. The degree of extraction and the mass-transfer rate were best when the agitation speed and the superficial velocities of aqueous and solvent phases were adjusted to 690 rpm, 0.831 mm/s, and 1.385 mm/s, respectively. The better efficiency was achieved using the ionic liquid with 0.02 mol/L concentration, 96.52% Eu(III) extraction in comparison to the same condition without the presence of ionic liquids with Cyanex272 (0.5 mol/L, 99.66%). With the analysis of the data, it was noted that the increase in the operating parameters has a positive influence on the holdup, degree of extraction, and mass-transfer rates. The percentage increase equal to 33.57% for overall mass-transfer coefficients was obtained with the increment of mixing in the column. The results showed that the mass transfer is associated with reactive resistance. The previous correlation did not explain the behavior of the system correctly in the reactive mode. Finally, the empirical models using the Sherwood number were developed to correlate the mass-transfer coefficient.