L. P. Badheka

Extraction of actinides and fission products by octyl(phenyl)-N,N-diisobutylcarbamoylmethyl-phosphine oxide from nitric acid media.

Extraction of promethium(III), uranium(VI), plutonium(IV), americium(III), zirconium(IV), ruthenium(III), iron(III) and palladium(II) has been carried out with a mixture of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) and tributyl phosphate (TBP) in dodecane. The effects of nitric acid, TBP and CMPO concentrations on the extraction of these metal ions have been studied. The nature of the species of the above metal ions extracted into the organic phase has been suggested.

Partitioning of actinides from high-level waste streams of purex process using mixtures of CMPO and TBP in dodecane

Abstract The extraction of actinides from high active aqueous raffinate waste (HAW) as well as high-level waste (HLW) solutions arising from Purex processing of thermal reactor fuels has been studied using a mixture of octyl(phenyl)-N N-diisobutylcarbamoyl-methylphosphine oxide (CMPO) and TBP in dodecane. The results on the extraction and stripping of actinides, lanthanides, and other fission products are discussed. Optimum conditions are proposed for the efficient recovery of residual actinides from HAW and HLW streams by CMPO extraction followed by their selective stripping with suitable reagents. Experiments on the extraction and separation of actinides and lanthanides by CMPO in the presence of TBP in dodecane have also been carried out with U(VI) and Nd(III) to arrive at the limiting conditions for avoiding third-phase formation.

Development of the diamex process for treating phwr high-level liquid waste

Abstract The extraction behavior of actinides like U(VI), Pu(IV), and Am(III) as well as of fission products like Tc(VII), Zr(IV), Eu(III), and structural material Fe(III) using nitric acid/simulated pressurized heavy water reactor-high-level waste solution as aqueous phase and N,N’-dimethyl-N,N’ dibutyl tetra decyl malonamide (DMDBTDMA) in n-dodecane as solvent was investigated. The present work contributes significantly toward the development of nonphosphorous (environmentally friendly) extractant capable of partitioning long-lived actinides and fission products like 99Tc from relatively short lived fission products like 90Sr and 137Cs as well as inactive components present in high-level waste. The DAm values determined in the temperature range between 15 and 45°C showed a gradual decrease with increase in temperature throughout the acidity range. The effect of N,N di-2-ethylhexyl acetamide (D2EHAA) as phase modifier on the physicochemical properties of DMDBTDMA/n-dodecane solvent was investigated and could be correlated with parameters like the limiting organic concentration value of HNO3, DAm, or phase disengagement time. Overall comparison of diamide extraction (Diamex) and transuranium extraction (Truex) solvents has been made.

Tail-end purification of americium from plutonium loading effluents using a mixture of octyl (phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide and tri-N-butyl phosphate

The tail-end purification of Am from Pu loading effluents in 7.5M HNO3 containing ∼160 mg l−1 Am and ∼1.2 mg l−1 Pu has been carried out. With 0.2M CMPO+1.2M TBP in dodecane as the extractant and stripping by 0.04M HNO3+0.05M NaNO2, the Pu level is brought down to ∼31.2 μg l−1. When the acidity was reduced to 4.2M HNO3, one contact with 20% TLA/dodecane and subsequent extraction by a mixture of CMPO and TBP and stripping with 0.04M HNO3+0.05M NaNO2 gave Am samples without any detectable amounts of Pu. The recovery of Am was ∼90% by the first procedure and ∼98% by the second one.

Solvent extracted and extraction chromatographically adsorbed complexes of bifunctional extractants with f-elements

The IR spectra of the solvent extracted and extraction chromatographically adsorbed complexes of HNO3, Nd(III), Th(IV) and U(VI) with bifunctional extractants dihexyl N,N-diethylcarbamoylmethylophosphonate (CMP) and octyl (phenyl)-N,N-diisobutylcarbamoyl-methylphosphine oxide (CMPO) have been recorded. The shifts in the P=0 and C=0 streching frequencies have been interpreted. The nitrate ions bound with metal ions were found to be bidentate. The nature of binding of the extractant to the metal ions in the solvent extracted and extraction chromatographically adsorbed complexes were found to be similar.

Neolignans from Indian Piper Species: Structure of Hookerinone A, a novel Neolignan

Abstract A new neolignan hookerinone A (1) along with three other members of the same group viz. kadsurin A (2), isodihydrofutoquinol A (3) and isodihydrofutoquinol B (4) have been isolated from three Indian Piper species. The structure of the new compound has been elucidated as (8R, 1′R or 8S, 1′S)-4-[2-(1, 3-benzodioxolo-5-yl)-1-methylethyl]-2,5-dimethoxy-1-propenyl-2,5-cyclohexadienone, on the basis of 2D- NOESY, HC-COSY, COLOC and other 2D-NMR techniques.