ASTM_C_1845_-_16.pdf

Designation:C184516Standard Practice forThe Separation of Lanthanide Elements from UraniumMatrices Using High Pressure Ion Chromatography(HPIC)for Isotopic Analyses by Inductively Coupled Plasma MassSpectrometry(ICP-MS)1This standard is issued under the fixed designation C1845;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice provides instructions for the rapid separa-tion of lanthanide elements using high pressure ion chroma-tography(HPIC)from dissolved uranium materials such as:nuclear fuels,uranium ores,hydrolyzed UF6,and depleted,natural,or enriched oxides/powders,or metals.Whenoptimized,this technique will produce purified elementalfractions of the lanthanide elements isolated from the bulkuranium matrix allowing for isotopic assay using inductivelycoupled plasma mass spectrometry(ICP-MS).1.2 This practice is most applicable for analyte concentra-tions of nanograms per gram uranium or higher.For ICP-MSdetection and measurement of analyte concentrations lowerthan this,it would be necessary to perform additional pre-cleanup or concentration techniques,or both,which are notaddressed in this practice.1.3 When combined with isotope dilution,this practice canalso be used for improved precision assays of the lanthanideelements using the principle of isotope dilution mass spectrom-etry(IDMS).1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thispractice.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C859 Terminology Relating to Nuclear MaterialsC1052 Practice for Bulk Sampling of Liquid UraniumHexafluorideC1075 Practices for Sampling Uranium-Ore ConcentrateC1168 Practice for Preparation and Dissolution of PlutoniumMaterials for AnalysisC1347 Practice for Preparation and Dissolution of UraniumMaterials for AnalysisC1689 Practice for Subsampling of Uranium HexafluorideC1769 Practice for Analysis of Spent Nuclear Fuel to De-termine Selected Isotopes and Estimate Fuel BurnupD1193 Specification for Reagent WaterE105 Practice for Probability Sampling of Materials3.Terminology3.1 DefinitionsFor definitions of terms used in thispractice,refer to Terminology C859.4.Summary of Practice4.1 Solid samples are dissolved according to PracticesC1168,C1347,or other appropriate methods.Uraniumhexafluoride can be sampled in accordance with PracticesC1052 and C1689.The resulting dissolver solution is pro-cessed to produce solutions of isolated lanthanide elements formass spectrometric isotopic analysis.The elements are selec-tively separated from the dissolver solution and collected usingHPIC instrumentation equipped with automated fraction col-lection.Appropriate aliquots of the unseparated dissolutions1This practice is under the jurisdiction of ASTM Committee C26 on NuclearFuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods ofTest.Current edition approved June 1,2016.Published June 2016.DOI:10.1520/C1845-16.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 are taken to provide up to 100 ng/mL of a lanthanide elementon the analytical column to be separated from 3.5 mg/mL orless of uranium.In a strong nitric acid matrix,no pre-separation valence adjustments are necessary.NOTE1This practice has been verified to separate 0.7 mg of totaluranium from the lanthanide analytes.20 ng total of each analyte has beenshown to have efficient resolution on the column to yield purifiedelemental samples.If larger uranium and analytes sample sizes are beingconsidered,it is suggested that these be verified by the lab for efficienturanium removal and analyte resolution.4.2 For the separation HPIC sample aliquots are injectedusing a 200 L sample loop and loaded onto a 4 by 250 mmhigh pressure cation exchange column with sulfonic acidfunctional groups and an ion exchange capacity of 80micro-equivalents/columns.First,complexation and removalof the bulk dissolved uranium matrix is accomplished using adilute hydrochloric acid eluent which is directed to waste.Next,the lanthanide elements are selectively eluted off of thecolumn by chelation chromatography using a dilute solution of2-hydroxyisobutyric acid(-HIBA).Fractions are collected atautomated