Task-Specific Supported Liquid Membrane for Actinide Assay in Aqueous Streams by Thermal Ionization Mass Spectrometry.

Autor: Paul S; Fuel Chemistry Division , Bhabha Atomic Research Centre , Trombay, Mumbai 400 085 , India., Bhushan KS; Fuel Chemistry Division , Bhabha Atomic Research Centre , Trombay, Mumbai 400 085 , India., Goswami PG; Fuel Chemistry Division , Bhabha Atomic Research Centre , Trombay, Mumbai 400 085 , India.
Jazyk: angličtina
Zdroj: Analytical chemistry [Anal Chem] 2019 Nov 19; Vol. 91 (22), pp. 14383-14391. Date of Electronic Publication: 2019 Nov 01.
DOI: 10.1021/acs.analchem.9b02866
Abstrakt: Thermal ionization mass spectrometry is the most commonly used technique for the determination of Pu isotopic composition and concentration in complex matrices but involves multiple steps including sample pretreatment, removal of matrix, preconcentration of Pu, and loading on a rhenium filament for TIMS analysis. The present work reports the synthesis of the N , N '-dioctyl-α-hydroxyacetamide (DOHA) functionalized supported liquid membrane that offered dual functions: (i) matrix elimination and/or preconcentration of actinides from complex aqueous samples and (ii) served as a loading substrate for TIMS analysis. The ligand composition in the membrane can be tuned aiming either for selective preconcentration of Pu from an aqueous matrix or for bulk removal of actinides. The membrane, impregnated with 0.2 M DOHA in dodecane, showed very high selectivity for Pu IV in acidic medium, in the presence of other competing actinides, viz., Am III , U VI , and Np V . The membrane based loading in TIMS improved the sample utilization efficiency and ionization efficiency compared to the conventional solution loading technique, offering Pu analysis from a single Re filament, that served as both vaporization and ionization filament and direct determination of 238 Pu in the presence of 238 U, eliminating the requirement of alpha spectrometry. It was possible to achieve >80% reduction in analysis time and >95% reduction in secondary waste generation by the SLM-TIMS method, compared to conventional TIMS involving Pu purification by anion exchange resin. Pu concentrations in seawater and groundwater samples, synthetic urine, and dissolver solution of irradiated fuel were determined by SLM-TIMS, employing the isotope dilution (ID) technique, with very good accuracy and precision. The membrane, impregnated with 2 M DOHA in dodecane, showed strong affinity for actinides and was successfully employed for the removal of bulk actinides from aqueous samples with more than 96% recovery.
Databáze: MEDLINE