title: Retention studies on uranium, thorium and lanthanides with amide modified reverse phase support and its applications.
abstract: The retention behaviour of uranium and thorium was investigated on modified reverse phase supports using 3-oxo-pentanedioicacid bis-[bis-(2-ethyl-hexyl)-amide (OPAEHA), 3-oxo-pentanedioicacid bis diisobutyl amide (OPAIBA) and bis-2-ethylhexyl succinamic acid (BEHSA). alpha-Hydroxy isobutyric acid (alpha-HIBA) was employed as the complexing reagent for elution. Elution profiles of uranium and thorium were studied as a function of the modifier concentration, mobile phase composition and its pH. Based on these investigations, a novel high performance liquid chromatography (HPLC) based separation technique was developed using BEHSA modified support for the isolation and quantitative determination of lanthanides as a group in uranium matrix. Hundreds of samples obtained from pyrochemical reprocessing of molten salts containing lanthanides in uranium matrix (e.g. 1:20,000) were separated and determined within 7 min using the coated support. The advantage of the present HPLC technique lies in the simultaneous separation and assay of total lanthanides and uranium whereas other analytical methods necessitate the separation of uranium matrix prior to lanthanide assay.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Chennai 600036, India.
authors.forename: Ch Siva Kesava
authors.initials: ChS
authors.lastname: Raju
authors.forename: M S
authors.initials: MS
authors.lastname: Subramanian
authors.forename: N
authors.initials: N
authors.lastname: Sivaraman
authors.forename: T G
authors.initials: TG
authors.lastname: Srinivasan
authors.forename: P R
authors.initials: PR
authors.lastname: Vasudeva Rao
mesh_terms: D000577:Amides / Q000138:chemical synthesis / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D028581:Lanthanoid Series Elements / Q000302:isolation & purification*; D015203:Reproducibility of Results; D013386:Succinates / Q000138:chemical synthesis / Q000737:chemistry; D013910:Thorium / Q000302:isolation & purification*; D014501:Uranium / Q000302:isolation & purification*
chemical_list: D000577:Amides; D028581:Lanthanoid Series Elements; D013386:Succinates; C522858:bis-2-ethylhexyl succinamic acid; D014501:Uranium; D013910:Thorium