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Performance Measures x.x, x.x, and x.x. Automated Radiochemistry Efforts at LLNL. Presented to: Periodic Table of D.I. Mendeleev. The new superheavy elements January 21, 2009. Roger A. Henderson, Kenton J. Moody, Dawn A. Shaughnessy, and Julie M. Gostic*
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Performance Measures x.x, x.x, and x.x Automated Radiochemistry Efforts at LLNL Presented to: Periodic Table of D.I. Mendeleev. The new superheavy elements January 21, 2009 Roger A. Henderson, Kenton J. Moody, Dawn A. Shaughnessy, and Julie M. Gostic* Chemistry, Materials, Earth, and Life Sciences DirectorateLawrence Livermore National Laboratory *University of Nevada-Las Vegas LLNL-PRES-406833
Automated Radiochemistry Efforts at LLNL • Chemistry Desires for Automation • Speed • Reproducibility • Lower Dose to Operators • Begin with a Heavy Element application • Single Column chemistry • Automated column regeneration • Long operating periods (months!) • Basic Design Sample Detection Sample Introduction Sample Chemistry
Automated Radiochemistry Efforts at LLNL Columns! To Sample Detection
Automated Radiochemistry Efforts at LLNL • System Components • Cheminert valves, PEEK material, micro-electric actuation • ISCO peristaltic pumps • Tubing – FEP – ID = 0.03” (0.762 mm) • Columns – FEP tubing, 10cm length • Volumes • 0.762 mm tubing – 45.6 ml • 0.508 mm tubing – 20.3 ml • 0.254 mm tubing – 5.1 ml • Frits • PEEK, 0.5 m or 2 m Frit-In-A-Ferrule™
Automated Radiochemistry Efforts at LLNL • Sample Introduction • ICP style nebulizer • Frit collection • Accumulator Column
Automated Radiochemistry Efforts at LLNL • Sample production and detection • Electrospray? • Rapid for very small volumes. • Collection on mylar tape? • Adsorption onto functionalized surfaces • Rapid source prep. • Equivalent to electroplated sources. • Array of PIPS detectors for a and SF. • LabVIEW control
Automated Radiochemistry Efforts at LLNL • Why DGA?
Automated Radiochemistry Efforts at LLNL • Why DGA?
Automated Radiochemistry Efforts at LLNL • What is DGA? – Eichrom technologies commercial product • N,N,N’,N’-tetra-n-octyldiglycolamide (DGA Resin, Normal) • N,N,N’,N’-tetrakis-2-éthylhexyldiglycolamide (DGA Resin, Branched)
Automated Radiochemistry Efforts at LLNL • Why Db? • Good range of t1/2 for study, seconds to 1 day (268Db, terminal nuclide for the 288115 decay chain). • New chemical system for testing. • Chemistry is amenable to automation. • Provides testing platform for the automated chemistry system, to be run either rapidly or slowly.
Automated Radiochemistry Efforts at LLNL • Testing needs – • Ta, Hf, Pa, others? • Noted lack of F- (or other complexing agent) in the Eichrom data. • +5’s tend to form colloidal species without it • Method • Batch extraction studies • 10 – 20 mg Normal DGA resin • 1mL aqueous phase • Agitate for at least 10 min, typically 1 hour • Separate using 0.45mm syringe filter • g-spec for detection
Sample Loading: • 0.4 M HNO3/ 0.02 M HF, 1 mL • Strip 1 (Pa): • 0.4 M HNO3/0.1 M HF, 5 mL • Strip 2 (Ta): • 8M HNO3/0.1 M HF, 6 x 5 mL • Strip 3: • 0.1 M Ammonium Bioxalate, 5 mL Automated Radiochemistry Efforts at LLNL
Automated Radiochemistry Efforts at LLNL • Next Steps • Kinetics Study – Getting started • Eu+3 data from Eichrom • Not the case with +5’s • Hf – Local production from 175Lu (p,n) 175Hf